Agronomy

Article

22 pages, 4708 KiB

Open AccessEditor’s ChoiceArticle

Yield of Winter Oilseed Rape (Brassica napus L. var. napus) in a Short-Term Monoculture and the Macronutrient Accumulation in Relation to the Dose and Method of Sulphur Application

by Mariusz Stepaniuk and Aleksandra Głowacka

Agronomy 2022, 12(1), 68; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010068 - 28 Dec 2021

Cited by 6 | Viewed by 2934

Abstract

The objective of this study was to assess the yield efficiency of sulphur-enhanced fertilisers, depending on the dose and application method, in a short-lived (three-year) monoculture of winter oilseed rape under the climate and soil conditions of south-eastern Poland. The experiment was carried [...] Read more.

The objective of this study was to assess the yield efficiency of sulphur-enhanced fertilisers, depending on the dose and application method, in a short-lived (three-year) monoculture of winter oilseed rape under the climate and soil conditions of south-eastern Poland. The experiment was carried out between 2010 and 2013 on winter oilseed rape (Brassica napus L. var. napus) of the Orlando variety, fertilised with different sulphur doses—0, 20, 40 or 60 kg S ha⁻¹ applied in different method—soil application sowing, foliar application in the spring, and soil application sowing + foliar application in the spring (combined application). Following the harvest, seed and straw yields and the content of macroelements (N, S, P, K, Ca and Mg) in the seed and straw samples were determined. The harvest indices were also established for each of these elements. The impact of sulphur on winter oilseed rape yield depended significantly on both the dose and the application method. Even at the lowest dose (20 kg·ha⁻¹), sulphur materially increased seed yield, regardless of the application method. With autumn soil application and foliar application, differences between the lowest dose and the higher doses (40 and 60 kg·ha⁻¹) were not significant. However, with combined application, the highest dose (60 kg·ha⁻¹) significantly increased yield compared to the lower doses. In general, all the fertilisation approaches significantly increased the N, P, K, Ca and Mg contents compared to the control sample, but the differences between them were not substantial. Each of the sulphur application approaches decreased the harvest index for sulphur. The foliar application of each of the doses decreased the harvest indices for N, P, K and Ca. The soil application of 20 kg·ha⁻¹, and the mixed application of 40 and 60 kg·ha⁻¹, all increased the harvest indices for P, K and Ca. Full article

(This article belongs to the Special Issue Crop Nutrient Requirements and Advanced Fertilizer Management Strategies)

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16 pages, 1010 KiB

Open AccessEditor’s ChoiceArticle

Biofortification of Diverse Basmati Rice Cultivars with Iodine, Selenium, and Zinc by Individual and Cocktail Spray of Micronutrients

by Asif Naeem, Muhammad Aslam, Mumtaz Ahmad, Muhammad Asif, Mustafa Atilla Yazici, Ismail Cakmak and Abdul Rashid

Agronomy 2022, 12(1), 49; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010049 - 27 Dec 2021

Cited by 12 | Viewed by 3665

Abstract

Given that an effective combined foliar application of iodine (I), selenium (Se), and zinc (Zn) would be farmer friendly, compared to a separate spray of each micronutrient, for the simultaneous biofortification of grain crops, we compared effectiveness of foliar-applied potassium iodate (KIO₃ [...] Read more.

Given that an effective combined foliar application of iodine (I), selenium (Se), and zinc (Zn) would be farmer friendly, compared to a separate spray of each micronutrient, for the simultaneous biofortification of grain crops, we compared effectiveness of foliar-applied potassium iodate (KIO₃, 0.05%), sodium selenate (Na₂SeO₄, 0.0024%), and zinc sulfate (ZnSO₄∙7H₂O, 0.5%), separately and in their combination (as cocktail) for the micronutrient biofortification of four Basmati cultivars of rice (Oryza sativa L.). Foliar-applied, each micronutrient or their cocktail did not affect rice grain yield, but grain yield varied significantly among rice cultivars. Irrespective of foliar treatments, the brown rice of cv. Super Basmati and cv. Kisan Basmati had substantially higher concentration of micronutrients than cv. Basmati-515 and cv. Chenab Basmati. With foliar-applied KIO₃, alone or in cocktail, the I concentration in brown rice increased from 12 to 186 µg kg⁻¹. The average I concentration in brown rice with foliar-applied KIO₃ or cocktail was 126 μg kg⁻¹ in cv. Basmati-515, 160 μg kg⁻¹ in cv. Chenab Basmati, 153 μg kg⁻¹ in cv. Kisan Basmati, and 306 μg kg⁻¹ in cv. Super Basmati. Selenium concentration in brown rice increased from 54 to 760 µg kg⁻¹, with foliar-applied Na₂SeO₄ individually and in cocktail, respectively. The inherent Zn concentration in rice cultivars ranged between 14 and 19 mg kg⁻¹ and increased by 5–6 mg Zn per kg grains by foliar application of ZnSO₄∙7H₂O and cocktail. The results also showed the existence of genotypic variation in response to foliar spray of micronutrients and demonstrated that a foliar-applied cocktail of I, Se, and Zn could be an effective strategy for the simultaneous biofortification of rice grains with these micronutrients to address the hidden hunger problem in human populations. Full article

(This article belongs to the Topic Plant Nutrition Biofortification)

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15 pages, 1280 KiB

Open AccessEditor’s ChoiceArticle

Yield and Quality Prediction of Winter Rapeseed—Artificial Neural Network and Random Forest Models

by Dragana Rajković, Ana Marjanović Jeromela, Lato Pezo, Biljana Lončar, Federica Zanetti, Andrea Monti and Ankica Kondić Špika

Agronomy 2022, 12(1), 58; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010058 - 27 Dec 2021

Cited by 33 | Viewed by 3827

Abstract

As one of the greatest agricultural challenges, yield prediction is an important issue for producers, stakeholders, and the global trade market. Most of the variation in yield is attributed to environmental factors such as climate conditions, soil type and cultivation practices. Artificial neural [...] Read more.

As one of the greatest agricultural challenges, yield prediction is an important issue for producers, stakeholders, and the global trade market. Most of the variation in yield is attributed to environmental factors such as climate conditions, soil type and cultivation practices. Artificial neural networks (ANNs) and random forest regression (RFR) are machine learning tools that are used unambiguously for crop yield prediction. There is limited research regarding the application of these mathematical models for the prediction of rapeseed yield and quality. A four-year study (2015–2018) was carried out in the Republic of Serbia with 40 winter rapeseed genotypes. The field trial was designed as a randomized complete block design in three replications. ANN, based on the Broyden–Fletcher–Goldfarb–Shanno iterative algorithm, and RFR models were used for prediction of seed yield, oil and protein yield, oil and protein content, and 1000 seed weight, based on the year of production and genotype. The best production year for rapeseed cultivation was 2016, when the highest seed and oil yield were achieved, 2994 kg/ha and 1402 kg/ha, respectively. The RFR model showed better prediction capabilities compared to the ANN model (the r² values for prediction of output variables were 0.944, 0.935, 0.912, 0.886, 0.936 and 0.900, for oil and protein content, seed yield, 1000 seed weight, oil and protein yield, respectively). Full article

(This article belongs to the Special Issue Advances in Modelling Cropping Systems to Improve Yield and Quality)

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12 pages, 1429 KiB

Open AccessEditor’s ChoiceArticle

Biochemical and Rapid Molecular Analyses to Identify Glyphosate Resistance in Lolium spp.

by Maria Gerakari, Nikolina Cheimona, Eleni Tani, Ilias Travlos, Demosthenis Chachalis, Donato Loddo, Solvejg Kopp Mathiassen, Thomas K. Gitsopoulos, Laura Scarabel, Silvia Panozzo, Michael Kristensen, Per Kudsk and Maurizio Sattin

Agronomy 2022, 12(1), 40; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010040 - 25 Dec 2021

Viewed by 3051

Abstract

Lolium spp. are troublesome weeds mainly found in winter cereal crops worldwide, including Europe. In recent years resistant mechanisms have been evolved to several important herbicides. In this study we investigated the mechanisms responsible for conferring glyphosate resistance in some Lolium spp. populations. [...] Read more.

Lolium spp. are troublesome weeds mainly found in winter cereal crops worldwide, including Europe. In recent years resistant mechanisms have been evolved to several important herbicides. In this study we investigated the mechanisms responsible for conferring glyphosate resistance in some Lolium spp. populations. A holistic approach was used, based on dose-response experiments, determination of shikimic acid concentration in plant leaf tissue, as well as molecular analyses. More specifically, in three Lolium spp. populations the existence of a mutation in the Pro-106 codon of the 5-enolpyruvylshikimate-3 phosphate synthase (EPSPS) gene was investigated as well as the relative transcript levels of four ABC-transporter genes were monitored at three time points after glyphosate application. The results demonstrated that glyphosate resistance is a multifactor phenomenon. Relative transcript levels of the ABC-transporter genes were abundant at very early time points after glyphosate treatments. Dose-response experiments and shikimate analyses were in accordance with the findings of the quantitative PCR (qPCR) analyses. We suggest that relative expression ratio of ABC-transporter genes can be a useful tool to rapidly identify Lolium spp. populations resistant to glyphosate. Full article

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14 pages, 1204 KiB

Open AccessEditor’s ChoiceArticle

Interactive Effects of Biochar, Nitrogen, and Phosphorous on the Symbiotic Performance, Growth, and Nutrient Uptake of Soybean (Glycine max L.)

by Dilfuza Egamberdieva, Hua Ma, Moritz Reckling, Richard Ansong Omari, Stephan Wirth and Sonoko D. Bellingrath-Kimura

Agronomy 2022, 12(1), 27; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010027 - 24 Dec 2021

Cited by 5 | Viewed by 4439

Abstract

Numerous studies reported the positive effect of soil amendment with biochar on plant development. However, little is known about biochar and its interrelation with nitrogen (N) and phosphorous (P) additions and their impact on plant growth. We carried out greenhouse experiments to understand [...] Read more.

Numerous studies reported the positive effect of soil amendment with biochar on plant development. However, little is known about biochar and its interrelation with nitrogen (N) and phosphorous (P) additions and their impact on plant growth. We carried out greenhouse experiments to understand the interactive effects of nitrogen and phosphorus supply, as well as biochar amendment, on the symbiotic performance of soybean (Glycine max L.) with Bradyrhizobium japonicum, and plant growth and nutrient uptake. The biochar was produced from maize by heating at 600 °C for 30 min and used for pot experiments at an application rate of 2%. Plants were fertilized with two different concentrations of P (KH₂PO₄) and N (NH₄NO₃). Biochar application significantly increased the dry weight of soybean root and shoot biomass, by 34% and 42%, under low nitrogen and low phosphorus supply, respectively. Bradyrhizobium japonicum inoculation enhanced the dry weight of shoot biomass significantly, by 41% and 67%, in soil without biochar and with biochar addition, respectively. The nodule number was 19% higher in plants grown under low N combined with low or high P, than in high N combinations, while biochar application increased nodule number in roots. Moreover, biochar application increased N uptake of plants in all soil treatments with N or P supply, compared with B. japonicum-inoculated and uninoculated plants. A statistical difference in P uptake of plants between biochar and nutrient levels was observed with low N and high P supply in the soil. Our results show that the interactions between nitrogen, phosphorus, and biochar affect soybean growth by improving the symbiotic performance of B. japonicum and the growth and nutrition of soybean. We observed strong positive correlations between plant shoot biomass, root biomass, and N and P uptake. These data indicated that the combined use of biochar and low N, P application can be an effective approach in improving soybean growth with minimum nutrient input. Full article

(This article belongs to the Special Issue Nutrient Recycling: Reduction in the Application of Mineral Fertilizers by Optimization of the Organic Wastes)

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10 pages, 1386 KiB

Open AccessEditor’s ChoiceArticle

Changes in Soil Organic Carbon and Its Labile Fractions after Land Conversion from Paddy Fields to Woodlands or Corn Fields

by Linlin Si, Wenhai Mi, Yan Sun, Wanghai Tao, Jihong Zhang and Lijun Su

Agronomy 2022, 12(1), 29; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010029 - 24 Dec 2021

Cited by 4 | Viewed by 3594

Abstract

Land use change could significantly affect soil organic carbon (SOC) and other soil chemical properties. However, the responses of soil labile C fractions at different soil depths to land-use change are not still clear. The aim of this study was to investigate the [...] Read more.

Land use change could significantly affect soil organic carbon (SOC) and other soil chemical properties. However, the responses of soil labile C fractions at different soil depths to land-use change are not still clear. The aim of this study was to investigate the effect of paddy field conversion on woodlands or corn fields on total soil organic C (TOC) and its labile C fractions including particulate organic C (POC), microbial biomass C (MBC), and potassium permanganate-oxidizable C (KMnO₄–C) along a 0–100 cm soil profile. Our results indicate that soil TOC concentrations increased by 3.88 g kg⁻¹ and 3.47 g kg⁻¹ in the 0–5 cm soil layer and 5.33 g kg⁻¹ and 4.68 g kg⁻¹ in the 5–20 cm soil layer during 13 years after the conversion from paddy fields to woodlands and corn fields, respectively. In the 20–40 cm soil layer, the woodlands had the highest TOC concentration (12.3 g kg⁻¹), which was 5.13 g kg⁻¹ and 3.5 g kg⁻¹ higher than that of the paddy and corn fields, respectively. The increase in TOC was probably due to the absence of soil disturbance and greater root residue input into the woodland soil. In corn fields, pig manure addition contributed to the increase in soil organic C concentrations. In addition, the proportion of soil KMnO₄–C increased after conversion from paddy fields to woodlands or corn fields in the 0–40 cm soil layer, ranging from 39.9–56.6% for the woodlands and 24.6–32.9% for the corn fields. The soil POC content was significantly higher in woodland and corn field soils than in paddy field soils at lower soil depths (5–40 cm). However, there were no differences in MBC contents in the whole soil profile between the woodlands and paddy fields. The KMnO₄–C and MBC was the most important factor affecting the CMI values through the whole 0–100 cm soil profile. Overall, converting paddy fields to woodlands or corn fields increased the TOC and labile C fractions in the 0–40 cm soil layer. Future studies should focus on the response of the deeper soil C pool to land-use change. Full article

(This article belongs to the Special Issue Applied Research and Extension in Agronomic Soil Fertility)

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19 pages, 44032 KiB

Open AccessEditor’s ChoiceArticle

Estimation of Stagnosol Hydraulic Properties and Water Flow Using Uni- and Bimodal Porosity Models in Erosion-Affected Hillslope Vineyard Soils

by Vilim Filipović, Jasmina Defterdarović, Vedran Krevh, Lana Filipović, Gabrijel Ondrašek, Filip Kranjčec, Ivan Magdić, Vedran Rubinić, Sanja Stipičević, Ivan Mustać, Marina Bubalo Kovačić, Hailong He, Amir Haghverdi and Horst H. Gerke

Agronomy 2022, 12(1), 33; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010033 - 24 Dec 2021

Cited by 8 | Viewed by 3534

Abstract

Erosion has been reported as one of the top degradation processes that negatively affect agricultural soils. The study objective was to identify hydropedological factors controlling soil water dynamics in erosion-affected hillslope vineyard soils. The hydropedological study was conducted at identically-managed Jastrebarsko (location I), [...] Read more.

Erosion has been reported as one of the top degradation processes that negatively affect agricultural soils. The study objective was to identify hydropedological factors controlling soil water dynamics in erosion-affected hillslope vineyard soils. The hydropedological study was conducted at identically-managed Jastrebarsko (location I), and Jazbina (II) and (III) sites with Stagnosol soils. Soil Hydraulic Properties (SHP) were estimated on intact soil cores using Evaporation and WP4C methods; soil hydraulic functions were fitted using HYPROP-FIT software. For Apg and Bg/Btg horizons, uni- and bimodal soil hydraulic models could be well fitted to data; although, the bimodal model performed better in particular cases where data indicated non-uniform pore size distribution. With these SHP estimations, a one-year (2020) water flow scenario was simulated using HYDRUS-1D to compare water balance results obtained with uni- and bimodal hydraulic functions. Simulation results revealed relatively similar flux distribution at each hillslope position between the water balance components infiltration, surface runoff, and drainage. However, at the bottom profile at Jastrebarsko, bimodality of the hydraulic functions led to increased drainage. Soil water storage was reduced, and the vertical movement increased due to modified soil water retention curve shapes. Adequate parameterization of SHP is required to capture the hydropedological response of heterogenous erosion-affected soil systems. Full article

(This article belongs to the Special Issue Land Management Impacts on Soil Properties and Soil Erosion Processes)

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20 pages, 2480 KiB

Open AccessEditor’s ChoiceArticle

Rapid Detection of Urea Fertilizer Effects on VOC Emissions from Cucumber Fruits Using a MOS E-Nose Sensor Array

by Sana Tatli, Esmaeil Mirzaee-Ghaleh, Hekmat Rabbani, Hamed Karami and Alphus Dan Wilson

Agronomy 2022, 12(1), 35; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010035 - 24 Dec 2021

Cited by 30 | Viewed by 4220

Abstract

The widespread use of nitrogen chemical fertilizers in modern agricultural practices has raised concerns over hazardous accumulations of nitrogen-based compounds in crop foods and in agricultural soils due to nitrogen overfertilization. Many vegetables accumulate and retain large amounts of nitrites and nitrates due [...] Read more.

The widespread use of nitrogen chemical fertilizers in modern agricultural practices has raised concerns over hazardous accumulations of nitrogen-based compounds in crop foods and in agricultural soils due to nitrogen overfertilization. Many vegetables accumulate and retain large amounts of nitrites and nitrates due to repeated nitrogen applications or excess use of nitrogen fertilizers. Consequently, the consumption of high-nitrate crop foods may cause health risks to humans. The effects of varying urea–nitrogen fertilizer application rates on VOC emissions from cucumber fruits were investigated using an experimental MOS electronic-nose (e-nose) device based on differences in sensor-array responses to volatile emissions from fruits, recorded following different urea fertilizer treatments. Urea fertilizer was applied to cucumber plants at treatment rates equivalent to 0, 100, 200, 300, and 400 kg/ha. Cucumber fruits were then harvested twice, 4 and 5 months after seed planting, and evaluated for VOC emissions using an e-nose technology to assess differences in smellprint signatures associated with different urea application rates. The electrical signals from the e-nose sensor array data outputs were subjected to four aroma classification methods, including: linear and quadratic discriminant analysis (LDA-QDA), support vector machines (SVM), and artificial neural networks (ANN). The results suggest that combining the MOS e-nose technology with QDA is a promising method for rapidly monitoring urea fertilizer application rates applied to cucumber plants based on changes in VOC emissions from cucumber fruits. This new monitoring tool could be useful in adjusting future urea fertilizer application rates to help prevent nitrogen overfertilization. Full article

(This article belongs to the Special Issue Development of Tools for Diagnosing and Counteracting Ammonium Toxicity in Model and Crop Plants)

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11 pages, 621 KiB

Open AccessEditor’s ChoiceArticle

Ecological Adaptability of Some Cultivars and Breeding Samples of Origanum vulgare L.

by Elena Myagkikh, Svetlana Babanina, Alexander Mishnev, Ludmila Radchenko, Vladimir Pashtetskiy, Natalya Nevkrytaya and Olga Loretts

Agronomy 2022, 12(1), 16; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy12010016 - 23 Dec 2021

Cited by 3 | Viewed by 3909

Abstract

Since the registry of common oregano (Origanum vulgare L.) cultivars does not involve regionalization, a comprehensive study of cultivars bred by different institutions in the intended cultivation region is valuable and relevant. The objective of the research was to assess the possibility [...] Read more.

Since the registry of common oregano (Origanum vulgare L.) cultivars does not involve regionalization, a comprehensive study of cultivars bred by different institutions in the intended cultivation region is valuable and relevant. The objective of the research was to assess the possibility of using various indices of ecological adaptability originally developed for grain crops for their use in the most adapted genotypes’ selection (breeding samples and cultivars) of Origanum vulgare L. to the temperate climate of the Crimean Peninsula. The research was carried out in the piedmont zone of Crimea from 2016 to 2019. The study material consisted of breeding samples No. 10 and No. 82 from the collection of FSBSI “Research Institute of Agriculture of Crimea”, as well as cultivars Zima, Raduga, and Slavnitsa selected by the All-Russian Scientific Research Institute of Medicinal and Aromatic Plants (ARSRIMAP). Genotype had the greatest influence on yield of fresh oregano material (43%) with the influence of the weather conditions of the year being 2%. On the contrary, meteorological conditions had a much greater effect on the essential oil accumulation and its areal yield, which were 30% and 25%, respectively. In terms of the coefficient of ecological variation of fresh yield, sample No. 82 and Slavnitsa cultivar were the best (11.47–16.7%). The local genotypes No. 10 and No. 82 varied less by the essential oil content and its yield. The genotype effect value was greater than 0 in the Raduga cultivar and local genotype No. 82 for the yield, but only in No. 82 genotype for the other two characteristics. Cultivars Zima and Raduga were classified as intensive (b_i > 1) by the environmental flexibility of fresh yield, while local genotype No. 82 and Slavnitsa cultivar formed the group of intensive ones by essential oil content and essential oil yield. Local genotypes No. 10 and No. 82 were better than the introduced cultivars in terms of essential oil content homeostability and essential oil yield (Hom = 1.91–2.18). Thus, local genotypes proved to be more adapted to the region’s conditions in terms of essential oil accumulation. However, they were inferior to the registered cultivars of ARSRIMAP breeding in terms of fresh yield. Full article

(This article belongs to the Special Issue Innovative Technologies in Crop Production and Animal Husbandry)

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19 pages, 2177 KiB

Open AccessEditor’s ChoiceArticle

Improving Nitrogen Status Estimation in Malting Barley Based on Hyperspectral Reflectance and Artificial Neural Networks

by Karel Klem, Jan Křen, Ján Šimor, Daniel Kováč, Petr Holub, Petr Míša, Ilona Svobodová, Vojtěch Lukas, Petr Lukeš, Hana Findurová and Otmar Urban

Agronomy 2021, 11(12), 2592; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122592 - 20 Dec 2021

Cited by 5 | Viewed by 2908

Abstract

Malting barley requires sensitive methods for N status estimation during the vegetation period, as inadequate N nutrition can significantly limit yield formation, while overfertilization often leads to an increase in grain protein content above the limit for malting barley and also to excessive [...] Read more.

Malting barley requires sensitive methods for N status estimation during the vegetation period, as inadequate N nutrition can significantly limit yield formation, while overfertilization often leads to an increase in grain protein content above the limit for malting barley and also to excessive lodging. We hypothesized that the use of N nutrition index and N uptake combined with red-edge or green reflectance would provide extended linearity and higher accuracy in estimating N status across different years, genotypes, and densities, and the accuracy of N status estimation will be further improved by using artificial neural network based on multiple spectral reflectance wavelengths. Multifactorial field experiments on interactive effects of N nutrition, sowing density, and genotype were conducted in 2011–2013 to develop methods for estimation of N status and to reduce dependency on changing environmental conditions, genotype, or barley management. N nutrition index (NNI) and total N uptake were used to correct the effect of biomass accumulation and N dilution during plant development. We employed an artificial neural network to integrate data from multiple reflectance wavelengths and thereby eliminate the effects of such interfering factors as genotype, sowing density, and year. NNI and N uptake significantly reduced the interannual variation in relationships to vegetation indices documented for N content. The vegetation indices showing the best performance across years were mainly based on red-edge and carotenoid absorption bands. The use of an artificial neural network also significantly improved the estimation of all N status indicators, including N content. The critical reflectance wavelengths for neural network training were in spectral bands 400–490, 530–570, and 710–720 nm. In summary, combining NNI or N uptake and neural network increased the accuracy of N status estimation to up 94%, compared to less than 60% for N concentration. Full article

(This article belongs to the Special Issue Crop Nutrient Requirements and Advanced Fertilizer Management Strategies)

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33 pages, 5795 KiB

Open AccessEditor’s ChoiceArticle

The Perfect Match: Adjusting High Tree Density to Rootstock Vigor for Improving Cropping and Land Use Efficiency of Sweet Orange

by Eduardo Augusto Girardi, João Gabriel Panegossi Sola, Marcelo da Silva Scapin, Alécio Souza Moreira, Renato Beozzo Bassanezi, Antonio Juliano Ayres and Leandro Peña

Agronomy 2021, 11(12), 2569; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122569 - 17 Dec 2021

Cited by 7 | Viewed by 3546

Abstract

The rise in the productivity of sweet orange in Brazil has been related to the use of superior rootstocks and higher tree density, among other factors. In order to investigate whether the cropping system and the land use efficiency would benefit from more [...] Read more.

The rise in the productivity of sweet orange in Brazil has been related to the use of superior rootstocks and higher tree density, among other factors. In order to investigate whether the cropping system and the land use efficiency would benefit from more intensive cultivation, the performance of Valencia sweet orange was evaluated over nine years on four rootstocks, which induced contrasting vigor, at 513, 696 and 1000 trees·ha⁻¹. Agronomic Institute of Campinas (IAC) 1697 and IAC 1710 citrandarins, and diploid and allotetraploid (4×) Swingle citrumelos were classified as semi-dwarfing, super-standard, standard, and dwarfing rootstocks, respectively. The fruit yield per tree was decreased at higher tree densities, notably for more vigorous rootstocks. Conversely, the cumulative productivity was increased over the evaluation period by 27% at 1000 trees·ha⁻¹, irrespective of the rootstock, and the most vigorous rootstock resulted in 2.5 times higher production than the dwarfing one on average. Most fruit quality parameters were seldom influenced by the tree density, while the rootstock was a decisive factor in improving the quality and the soluble solids content. Dwarfing rootstocks allowed for harvesting 17% more fruit per minute by manual pickers. Because the tree row volume per area is lower with such rootstocks, even at higher tree density, spray volume can be reduced, although appropriate equipment should be developed for better spray coverage on smaller trees. Nine years after planting under strict vector control, the cumulative incidence of huanglongbing-symptomatic trees on IAC 1710 was double that on Swingle 4×. Taken together, the results suggested that the land use efficiency in the citrus industry can be further improved by planting vigorous rootstocks at moderate to high tree densities. Nevertheless, obtaining highly productive semi-dwarfing and dwarfing rootstocks is the sine qua non for making high-density pedestrian sweet orange orchards more profitable. Full article

(This article belongs to the Special Issue Advances in Citrus Breeding, Genetics, Physiology and Horticultural Management)

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14 pages, 2640 KiB

Open AccessEditor’s ChoiceArticle

Growth, Quality, and Nitrogen Assimilation in Response to High Ammonium or Nitrate Supply in Cabbage (Brassica campestris L.) and Lettuce (Lactuca sativa L.)

by Jinnan Song, Jingli Yang and Byoung Ryong Jeong

Agronomy 2021, 11(12), 2556; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122556 - 16 Dec 2021

Cited by 20 | Viewed by 3535

Abstract

Plants grow better when they are supplied with a combination of ammonium (NH₄⁺) and nitrate (NO₃⁻) than when either one is supplied as the sole N (nitrogen) source. However, the effects of N forms on N metabolism [...] Read more.

Plants grow better when they are supplied with a combination of ammonium (NH₄⁺) and nitrate (NO₃⁻) than when either one is supplied as the sole N (nitrogen) source. However, the effects of N forms on N metabolism and major N assimilation enzymes in different plants, especially vegetables, are largely neglected. This study was conducted on two plants with distinct NH₄⁺ tolerances to compare the responses of two popular leafy vegetables, Korean cabbage (Brassica campestris L.) ‘Ssamchu’ and lettuce (Lactuca sativa L.) ‘Caesar green’, to the N source. To this end, plant growth and quality, photosynthesis, carbohydrate, N contents (in the forms of NO₃⁻, NO₂⁻, NH₄⁺, total protein), and key N assimilation-related enzyme (NR, NIR, GS, GDH) activities were investigated. When plants were subjected to one of three NH₄⁺:NO₃⁻ regimes, 0:100, 50:50, or 100:0, lettuce was relatively more tolerant while cabbage was extremely sensitive to high NH₄⁺. Both plants benefited more from being grown with 50:50 NH₄⁺:NO₃⁻, as evidenced by the best growth performance, ameliorated photosynthesis, and enriched carbohydrate (C) stock content. In addition, as compared to cabbage, the GS and GDH activities were reinforced in lettuce in response to an increasing external NH₄⁺ level, resulting in low NH₄⁺ accumulation. Our findings suggested that boosting or maintaining high GS and GDH activities is an important strategy for the ammonium tolerance in vegetables. Full article

(This article belongs to the Special Issue Water and Nitrogen Use Efficiency of Horticultural Crops under Abiotic Stress)

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11 pages, 1876 KiB

Open AccessEditor’s ChoiceArticle

Yield Assessment of Maize Varieties under Varied Water Application in Semi-Arid Conditions of Southern Mozambique

by Alfredo Nhantumbo, Sebastião Famba, Isaac Fandika, Armindo Cambule and Elijah Phiri

Agronomy 2021, 11(12), 2541; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122541 - 14 Dec 2021

Cited by 1 | Viewed by 2590

Abstract

Maize is one of the most important staple food crops in Mozambique. Its production is country-wise dominated by smallholder farmers (more than 90%) under rain-fed conditions, where the risk of crop failure is high, especially under semi-arid conditions in southern Mozambique. Several maize [...] Read more.

Maize is one of the most important staple food crops in Mozambique. Its production is country-wise dominated by smallholder farmers (more than 90%) under rain-fed conditions, where the risk of crop failure is high, especially under semi-arid conditions in southern Mozambique. Several maize genotypes have been developed for the broad agro-ecological zone adaptation but lack strong evidence about their productivity and yield stability to support decision-making in farming systems. In order to assess the yield and yield stability of maize genotypes under different environments, five identical on-station trials were implemented in the period 2017 to 2019, covering summer and winter seasons in the semi-arid region of southern Mozambique. The trials were established at the experimental station of the Universidade Eduardo Mondlane (UEM) in Sábie and at the Instituto de Investigação Agrária de Moçambique (IIAM) in Chókwe. A strip-plot design in a randomized complete block arrangement with 15 maize genotypes, and three water application (rainfall plus irrigation) levels in four replications was followed in a line-source irrigation arrangement. The water application levels varied from 151 mm to 804 mm, covering different water regimes. Under well-watered summer conditions, the genotypes G6 and G12 showed high yield and high grain yield stability. In the drier conditions, either in summer or winter, the G2 and G11 genotypes produced higher grain yield but with low stability. Both groups of genotypes have a high potential to be included in technology transfer packages to smallholder farmers to address food security or large-scale commercial farmers differently. Full article

(This article belongs to the Special Issue Advanced Irrigation Management for Mitigating Environmental Impacts on Agricultural Systems)

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23 pages, 2455 KiB

Open AccessEditor’s ChoiceArticle

Sustainable Development Goals, Financial Inclusion, and Grain Security Efficiency

by Shuaishuai Jia, Yushan Qiu and Cunyi Yang

Agronomy 2021, 11(12), 2542; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122542 - 14 Dec 2021

Cited by 38 | Viewed by 4139

Abstract

The 17 sustainable development goals proposed in the 2030 sustainable development agenda are the shared vision of all humanity. The core of achieving the sustainable development goals is to ensure grain security. Although financial inclusion is not separately incorporated into the United Nations [...] Read more.

The 17 sustainable development goals proposed in the 2030 sustainable development agenda are the shared vision of all humanity. The core of achieving the sustainable development goals is to ensure grain security. Although financial inclusion is not separately incorporated into the United Nations sustainable development goals, it is an essential basis for supporting all sustainable development goals. Financial inclusion plays a critical role in improving grain security efficiency to ensure sustainable grain security. According to the Financial Access Survey implemented by IMF, this study calculated the financial inclusion index and grain security efficiency of 121 countries from 2015 to 2019. Based on calculating the efficiency of grain security in production and distribution, this study used an econometric model to empirically examine the role of financial inclusion in improving grain security efficiency. The study found that financial inclusion can promote grain security efficiency from the two links of production and distribution. Still, the improvement of grain security efficiency by financial inclusion is mainly reflected in the distribution. Further, the study found that the advancement of financial inclusion promotes the efficiency of grain distribution through the effects of residents’ income distribution, residents’ income growth, and consumption capacity upgrading, which achieves the goal of ensuring grain security and promoting sustainable development. Full article

(This article belongs to the Special Issue Economy and Sociology in Sustainable Agriculture)

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18 pages, 1881 KiB

Open AccessEditor’s ChoiceArticle

Genomic Selection and Genome-Wide Association Studies for Grain Protein Content Stability in a Nested Association Mapping Population of Wheat

by Karansher S. Sandhu, Paul D. Mihalyov, Megan J. Lewien, Michael O. Pumphrey and Arron H. Carter

Agronomy 2021, 11(12), 2528; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122528 - 13 Dec 2021

Cited by 26 | Viewed by 5077

Abstract

Grain protein content (GPC) is controlled by complex genetic systems and their interactions and is an important quality determinant for hard spring wheat as it has a positive effect on bread and pasta quality. GPC is variable among genotypes and strongly influenced by [...] Read more.

Grain protein content (GPC) is controlled by complex genetic systems and their interactions and is an important quality determinant for hard spring wheat as it has a positive effect on bread and pasta quality. GPC is variable among genotypes and strongly influenced by the environment. Thus, understanding the genetic control of wheat GPC and identifying genotypes with improved stability is an important breeding goal. The objectives of this research were to identify genetic backgrounds with less variation for GPC across environments and identify quantitative trait loci (QTLs) controlling the stability of GPC. A spring wheat nested association mapping (NAM) population of 650 recombinant inbred lines (RIL) derived from 26 diverse founder parents crossed to one common parent, ‘Berkut’, was phenotyped over three years of field trials (2014–2016). Genomic selection models were developed and compared based on predictions of GPC and GPC stability. After observing variable genetic control of GPC within the NAM population, seven RIL families displaying reduced marker-by-environment interaction were selected based on a stability index derived from a Finlay–Wilkinson regression. A genome-wide association study identified eighteen significant QTLs for GPC stability with a Bonferroni-adjusted p-value < 0.05 using four different models and out of these eighteen QTLs eight were identified by two or more GWAS models simultaneously. This study also demonstrated that genome-wide prediction of GPC with ridge regression best linear unbiased estimates reached up to r = 0.69. Genomic selection can be used to apply selection pressure for GPC and improve genetic gain for GPC. Full article

(This article belongs to the Special Issue Wheat Breeding: Procedures and Strategies – Series Ⅱ)

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18 pages, 705 KiB

Open AccessEditor’s ChoiceArticle

Genetic Mapping of Quantitative Trait Loci for End-Use Quality and Grain Minerals in Hard Red Winter Wheat

by Shuhao Yu, Silvano O. Assanga, Joseph M. Awika, Amir M. H. Ibrahim, Jackie C. Rudd, Qingwu Xue, Mary J. Guttieri, Guorong Zhang, Jason A. Baker, Kirk E. Jessup and Shuyu Liu

Agronomy 2021, 11(12), 2519; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122519 - 11 Dec 2021

Cited by 7 | Viewed by 2854

Abstract

To meet the demands of different wheat-based food products, traits related to end-use quality become indispensable components in wheat improvement. Thus, markers associated with these traits are valuable for the timely evaluation of protein content, kernel physical characteristics, and rheological properties. Hereunder, we [...] Read more.

To meet the demands of different wheat-based food products, traits related to end-use quality become indispensable components in wheat improvement. Thus, markers associated with these traits are valuable for the timely evaluation of protein content, kernel physical characteristics, and rheological properties. Hereunder, we report the mapping results of quantitative trait loci (QTLs) linked to end-use quality traits. We used a dense genetic map with 5199 SNPs from a 90K array based on a recombinant inbred line (RIL) population derived from ‘CO960293-2’/‘TAM 111’. The population was evaluated for flour protein concentration, kernel characteristics, dough rheological properties, and grain mineral concentrations. An inclusive composite interval mapping model for individual and across-environment QTL analyses revealed 22 consistent QTLs identified in two or more environments. Chromosomes 1A, 1B, and 1D had clustered QTLs associated with rheological parameters. Glu-D1 loci from CO960293-2 and either low-molecular-weight glutenin subunits or gliadin loci on 1A, 1B, and 1D influenced dough mixing properties substantially, with up to 34.2% of the total phenotypic variation explained (PVE). A total of five QTLs associated with grain Cd, Co, and Mo concentrations were identified on 3B, 5A, and 7B, explaining up to 11.6% of PVE. The results provide important genetic resources towards understanding the genetic bases of end-use quality traits. Information about the novel and consistent QTLs provided solid foundations for further characterization and marker designing to assist selections for end-use quality improvements. Full article

(This article belongs to the Section Crop Breeding and Genetics)

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24 pages, 5084 KiB

Open AccessEditor’s ChoiceArticle

Phenylalanine Ammonia-Lyase (PAL) Genes Family in Wheat (Triticum aestivum L.): Genome-Wide Characterization and Expression Profiling

by Fatima Rasool, Muhammad Uzair, Muhammad Kashif Naeem, Nazia Rehman, Amber Afroz, Hussain Shah and Muhammad Ramzan Khan

Agronomy 2021, 11(12), 2511; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122511 - 10 Dec 2021

Cited by 29 | Viewed by 5949

Abstract

Phenylalanine ammonia-lyase (PAL) is the first enzyme in the phenylpropanoid pathway and plays a vital role in adoption, growth, and development in plants but in wheat its characterization is still not very clear. Here, we report a genome-wide identification of TaPAL genes and [...] Read more.

Phenylalanine ammonia-lyase (PAL) is the first enzyme in the phenylpropanoid pathway and plays a vital role in adoption, growth, and development in plants but in wheat its characterization is still not very clear. Here, we report a genome-wide identification of TaPAL genes and analysis of their transcriptional expression, duplication, and phylogeny in wheat. A total of 37 TaPAL genes that cluster into three subfamilies have been identified based on phylogenetic analysis. These TaPAL genes are distributed on 1A, 1B, 1D, 2A, 2B, 2D, 4A, 5B, 6A, 6B, and 6D chromosomes. Gene structure, conserved domain analysis, and investigation of cis-regulatory elements were systematically carried out. Chromosomal rearrangements and gene loss were observed by evolutionary analysis of the orthologs among Triticum urartu, Aegilops tauschii, and Triticum aestivum during the origin of bread wheat. Gene ontology analysis revealed that PAL genes play a role in plant growth. We also identified 27 putative miRNAs targeting 37 TaPAL genes. The high expression level of PAL genes was detected in roots of drought-tolerant genotypes compared to drought-sensitive genotypes. However, very low expressions of TaPAL10, TaPAL30, TaPAL32, TaPAL3, and TaPAL28 were recorded in all wheat genotypes. Arogenate dehydratase interacts with TaPAL29 and has higher expression in roots. The analysis of all identified genes in RNA-seq data showed that they are expressed in roots and shoots under normal and abiotic stress. Our study offers valuable data on the functioning of PAL genes in wheat. Full article

(This article belongs to the Special Issue Developing Temperature-Resilient Plants: Responses and Mitigation Strategies)

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25 pages, 24589 KiB

Open AccessEditor’s ChoiceArticle

Conceptual Design of a Comprehensive Farm Nitrogen Management System

by Fabian Weckesser, Frank Leßke, Marco Luthardt and Kurt-Jürgen Hülsbergen

Agronomy 2021, 11(12), 2501; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122501 - 9 Dec 2021

Cited by 9 | Viewed by 3600

Abstract

Data that are required for nutrient management are becoming increasingly available in digital format, leading to a high innovation potential for digital nitrogen (N) management applications. However, it is currently difficult for farmers to analyze, assess, and optimize N flows in their farms [...] Read more.

Data that are required for nutrient management are becoming increasingly available in digital format, leading to a high innovation potential for digital nitrogen (N) management applications. However, it is currently difficult for farmers to analyze, assess, and optimize N flows in their farms using the existing software. To improve digital N management, this study identified, evaluated, and systematized the requirements of stakeholders. Furthermore, digital farm N management tools with varying objectives in terms of system boundaries, data requirements, used methods and algorithms, performance, and practicality were appraised and categorized. According to the identified needs, the concept of a farm N management system (FNMS) software is presented which includes the following modules: (1) management of site and farm data, (2) determination of fertilizer requirements, (3) N balancing and cycles, (4) N turnover and losses, and (5) decision support. The aim of FNMS is to support farmers in their farming practices for increasing N efficiency and reducing environmentally harmful N surpluses. In this study, the conceptual requirements from the agricultural and computer science perspectives were determined as a basis for developing a consistent, scientifically sound, and user-friendly FNMS, especially applicable in European countries. This FNMS enables farmers and their advisors to make knowledge-based decisions based on comprehensive and integrated data. Full article

(This article belongs to the Topic Soil Fertility and Plant Nutrition for Sustainable Agriculture)

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24 pages, 1864 KiB

Open AccessEditor’s ChoiceArticle

Improvement of Nitrogen-Fertilizer Recommendation by Consideration of Long-Term Site and Cultivation Effected Mineralization

by Dietmar Meyer and Hartmut Kolbe

Agronomy 2021, 11(12), 2492; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122492 - 8 Dec 2021

Cited by 3 | Viewed by 2695

Abstract

Organic matter (OM) and nutrient nitrogen (N) play vital roles in the fertility and production of soil in accordance with goals of efficient environmental protection. This study aimed to show the extent to which N delivery can contribute to improving nitrogen fertilizer requirements [...] Read more.

Organic matter (OM) and nutrient nitrogen (N) play vital roles in the fertility and production of soil in accordance with goals of efficient environmental protection. This study aimed to show the extent to which N delivery can contribute to improving nitrogen fertilizer requirements (NFR) through comparative analysis of OM and N. Systems determining the NFR in agricultural practices have thus far been challenged to estimate the annual rate of mineralization of the soil. OM and N turnover was investigated through an available evaluation consisting of 546 representatively distributed permanent test and observation plots (TP) of the German Federal State of Saxony farms. A solid database of at least 10-year field plot card records from 2001 to 2010 was selected for the analysis. A program (BEFU) widely used in agricultural practice, along with the simplified process model CCB, were applied. For the calculation of the amount of mineral N fertilizers used, the results of three different methods for determining the NFR were compared with each other. The determination of the farmers’ demand (=actual condition of the TP) with a mean value of 132 kg N ha⁻¹ did not show a large difference between the calculated values with 137 kg N ha⁻¹ by the BEFU program. Based on the available results for the most important crop species cultivated in Saxony, there were clear differences in the considerations of the N delivery from the soil. The BEFU program was able to calculate an average N delivery of 17 kg N ha⁻¹ from tabulated data, whereas with the CCB process model, 66 kg N ha⁻¹ of mineralization was determined with a distinct higher deviation by taking into account the 10-year field histories. Using the N delivery of the TP by the CCB model, a clear reduction of the mean N fertilization level, to about 80 kg N ha⁻¹, was therefore achieved. These differences were particularly large for TP with organic fertilization (livestock), at a relatively low N fertilization level, and for certain crop species. With a high standard deviation, the average savings potential of mineral N fertilizers was 52–57 kg N ha⁻¹. After including the corrected values for the N mineral fertilization, a decrease in the N balances by an average of 20–25 kg N ha⁻¹ was ultimately achieved. In particular, the heavily oversupplied plots with D and E classification decreased by approximately 50%. The results of our study demonstrate clear improvements; therefore, increased efforts should be made in the future to optimize the determination of NFR using applicable methods that consider N mineralization in agricultural practice and consultation. Full article

(This article belongs to the Special Issue Nitrogen Cycle in Farming Systems)

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15 pages, 1757 KiB

Open AccessEditor’s ChoiceArticle

The Impact of Forest Fungi on Promoting Growth and Development of Brassica napus L.

by Grażyna B. Dąbrowska, Zuzanna Garstecka, Alina Trejgell, Henryk P. Dąbrowski, Wiktoria Konieczna and Iwona Szyp-Borowska

Agronomy 2021, 11(12), 2475; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122475 - 6 Dec 2021

Cited by 5 | Viewed by 2779

Abstract

Inoculation of plants with fungi has been shown to increase yields by improving germination, seedling vigor, plant growth, root morphogenesis, photosynthesis, and flowering through direct or indirect mechanisms. These mechanisms include solubilization and mineralization of nutrients, facilitating their uptake by plants, regulation of [...] Read more.

Inoculation of plants with fungi has been shown to increase yields by improving germination, seedling vigor, plant growth, root morphogenesis, photosynthesis, and flowering through direct or indirect mechanisms. These mechanisms include solubilization and mineralization of nutrients, facilitating their uptake by plants, regulation of hormone balance, production of volatile organic compounds and microbial enzymes, suppression of plant pathogens, and mitigation of abiotic stresses. In the presented experiments, the effect of selected forest soil fungi on the growth and development of Brassica napus L. seedlings was investigated. Inoculation was carried out in vivo and in pot experiments with ectomycorrhizal fungi typical for forest soils: Collybia tuberosa, Clitocybe sp., Laccaria laccata, Hebeloma mesophaeum, and Cyathusolla. It was shown that all analyzed fungi produced IAA. In the in vitro experiment, B. napus inoculated with L. laccata showed stimulated root growth and greater number of leaves compared to control plants. A similar stimulatory effect on lateral root formation was observed in cuttings grown in pots in the presence of the C. olla fungus. In the pot experiment, the seedlings inoculated with the L. laccata fungus also showed increased growth of shoots and biomass. The effect of inoculation with the tested fungal strains, especially C. olla, on the growth and development of oilseed rape was probably indirect, as it also contributed to an increase in the number of microorganisms, especially soil bacteria. The expression of the metallothioneins in B. napus (BnMT1-BnMT3) varied depending on the fungal species. The presence of C. olla significantly increased BnMT2 expression in oilseed rape. It was found that BnMT1 expression increased and BnMT3 transcripts decreased in plants growing in the presence of L. laccata. This indicates the involvement of BnMT in the adaptation of oilseed rape to growth in fungi presence. Full article

(This article belongs to the Section Soil and Plant Nutrition)

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18 pages, 3969 KiB

Open AccessEditor’s ChoiceArticle

Computational Interaction Analysis of Sirex noctilio Odorant-Binding Protein (SnocOBP7) Combined with Female Sex Pheromones and Symbiotic Fungal Volatiles

by Yi-Ni Li, En-Hua Hao, Han Li, Xiao-Hui Yuan, Peng-Fei Lu and Hai-Li Qiao

Agronomy 2021, 11(12), 2461; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122461 - 2 Dec 2021

Cited by 6 | Viewed by 2127

Abstract

Sirex noctilio, a major forestry quarantine pest, has spread rapidly and caused serious harm. However, existing methods still need to be improved because its olfactory interaction mechanisms are poorly understood. In order to study the role of male-specific protein SnocOBP7 in the [...] Read more.

Sirex noctilio, a major forestry quarantine pest, has spread rapidly and caused serious harm. However, existing methods still need to be improved because its olfactory interaction mechanisms are poorly understood. In order to study the role of male-specific protein SnocOBP7 in the protein–ligand interactions, we selected it as the object of computational simulation and analysis. By docking it with 11 ligands and evaluating free binding energy decomposition, the three best binding ligands were found to be female sex pheromones ((Z)-7-heptacosene and (Z)-7-nonacosene) and symbiotic fungal volatiles ((−)-globulol). Binding mode analysis and computational alanine scanning suggested that five residues play key roles in the binding of each female sex pheromone to SnocOBP7, whereas two residues play key roles in (−)-globulol binding. Phe108 and Leu36 may be the crucial sites via which SnocOBP7 binds female sex pheromones, whereas Met40 may regulate the courtship behavior of males, and Leu61 may be related to mating and host finding. Our studies predicted the function of SnocOBP7 and found that the interaction between SnocOBP7 and pheromone is a complex process, and we successfully predicted its binding key amino-acid sites, providing a basis for the development of new prevention and control methods relying on female sex pheromones and symbiotic fungi. Full article

(This article belongs to the Special Issue Biological Interactions of Pests)

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12 pages, 13321 KiB

Open AccessEditor’s ChoiceArticle

Influence of Substrate Composition and Container Size on the Growth of Tissue Culture Propagated Apple Rootstock Plants

by Jae Kyung Kim, Md. Rayhan Ahmed Shawon, Jin Hee An, Yeo Jong Yun, Soo Jeong Park, Jong Kuk Na and Ki Young Choi

Agronomy 2021, 11(12), 2450; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122450 - 30 Nov 2021

Cited by 10 | Viewed by 2811

Abstract

Substrate composition and container size are considered crucial for apple rootstock grown in a plug seedling system. This study investigated the effect of substrate material’s proportion and different container volumes on the growth of apple rootstock (M-9) plants propagated by tissue culture. In [...] Read more.

Substrate composition and container size are considered crucial for apple rootstock grown in a plug seedling system. This study investigated the effect of substrate material’s proportion and different container volumes on the growth of apple rootstock (M-9) plants propagated by tissue culture. In substrate composition, three different ratios of peat moss (PM): vermiculite (VL): perlite (PL) at 1:1:1 (S1), 1:2:3 (S2), 3:1:2 (S3) were used. For container size, plants were grown in 1000 mL (C1), 500 mL (C2), and 300 mL (C3) containers filled by 1:1:1 mixture of PM, VL and PL. In both cases, plants were treated eleven weeks in a green house. Our results demonstrate that the plant height, number of leaves, leaf area, shoot fresh weight and root fresh weight of apple rootstock were significantly higher in substrate composition S3 compared with S1 composition. However, chlorophyll content (SPAD) and photosynthesis rate were unaffected by variation of substrate composition. Furthermore, rootstock grown in C1 container showed plant height, number of leaves, leaf area, number of nodes, root length, shoot and root’s fresh and dry weight were significantly higher than those grown in C2 and C3 volume containers. The chlorophyll content and transpiration rate were not significantly affected by the different container volumes. These results suggest that the substrate ratio 3:1:2 of PM:VL:PL and container size 1000 mL were more favorable than other treatments for initial growth and development of the tissue culture propagated apple rootstock plants. Full article

(This article belongs to the Special Issue In Vitro Multiplication and Seed Production Technology)

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13 pages, 1393 KiB

Open AccessEditor’s ChoiceArticle

Comparative Efficiency of Mineral, Chelated and Nano Forms of Zinc and Iron for Improvement of Zinc and Iron in Chickpea (Cicer arietinum L.) through Biofortification

by Salwinder Singh Dhaliwal, Vivek Sharma, Arvind Kumar Shukla, Vibha Verma, Sanjib Kumar Behera, Prabhjot Singh, Saqer S. Alotaibi, Ahmed Gaber and Akbar Hossain

Agronomy 2021, 11(12), 2436; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122436 - 29 Nov 2021

Cited by 24 | Viewed by 3534

Abstract

Nanoparticles (NPs), due to their tailored properties, serve as potential sources of nutrients for the biofortification of edible grains. Chickpeas are a valued legume crop, widely consumed in developing countries. Thus, to improve the Zn and Fe content in chickpeas, a two-year study [...] Read more.

Nanoparticles (NPs), due to their tailored properties, serve as potential sources of nutrients for the biofortification of edible grains. Chickpeas are a valued legume crop, widely consumed in developing countries. Thus, to improve the Zn and Fe content in chickpeas, a two-year study was conducted to examine the potential of the foliar application of mineral (0.5% Zn and Fe), chelated (0.3% Zn and Fe) and nanoforms (0.5% ZFN) of fertilizers to enhance Zn and Fe content in chickpea. The foliar application of 0.5% ZnO NPs + 0.5% Fe₂O₃ NPs (ZFN) at the pre-flowering stage showed the highest potential to increase grain yield, Zn and Fe content and their uptake as a single foliar application of nano-fertilizers showed comparable results to two foliar applications of mineral and chelated forms. The grain and straw yield (14.07 and 33.04 q ha⁻¹, respectively) under ZFN treatment was significantly higher over the control (9.20 and 27.49 q ha⁻¹, respectively). A similar trend was observed for Zn and Fe content in grain (42.29 and 86.51 mg kg⁻¹, respectively). For nutrient uptake, ZFN treatment showed the highest uptake of Zn and Fe in grain (604.49 and 1226.22 g ha⁻¹, respectively) and straw (729.55 and 9184.67 g ha⁻¹, respectively). Thus, nano-fertilizers, due to their altered structural properties, demonstrated higher translocation over the mineral and chelated forms of nutrient fertilizers and thus improved yield and nutrient content to a greater extent. Thus, the foliar application of 0.5% ZnO NPs + 0.5% Fe₂O₃ NPs may prove to be a feasible option for the enrichment of chickpeas with Zn and Fe to ameliorate malnutrition in burgeoning human populations. Full article

(This article belongs to the Special Issue Development and Efficiency of New Micronutrient Fertilizers)

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27 pages, 1845 KiB

Open AccessEditor’s ChoiceArticle

Towards a Socio-Economic Model for Southwest Asian Cereal Domestication

by Alexander Weide

Agronomy 2021, 11(12), 2432; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122432 - 29 Nov 2021

Cited by 3 | Viewed by 3482

Abstract

Mechanisms of selection for domestication traits in cereals and other annual plants are commonly explained from agro-technological and genetic perspectives. Since archaeobotanical data showed that domestication processes were slow and protracted, research focused on genetic constraints and hypothetical ‘non-selective’ management regimes to explain [...] Read more.

Mechanisms of selection for domestication traits in cereals and other annual plants are commonly explained from agro-technological and genetic perspectives. Since archaeobotanical data showed that domestication processes were slow and protracted, research focused on genetic constraints and hypothetical ‘non-selective’ management regimes to explain the low selection rates. I argue that these factors only partially explain the observed patterns and develop a model that contextualises the archaeobotanical data in their socio-economic settings. I propose that developments towards individual storage by small household units and the gradual increase in storage capacities with the development of extended households represent key factors for establishing the conditions for selection, as these practices isolated individually managed and stored cereal subpopulations and gradually reduced the need to replenish grain stocks with grains from unmanaged populations. This genetic isolation resulted in stronger and more persistent selection rates and facilitated the genetic fixation of domestication traits on a population level. Moreover, individual storage facilities within buildings reflect gradual developments towards households as the social units that mobilised agricultural labour, which negotiated new sharing principles over cultivated resources and drove the intensification of cultivation practices. In this sense, selection rates and the slow domestication process can be understood as a function of limited food sharing networks and increased labour-inputs into early arable environments—socio-economic processes that also unfolded gradually over a protracted period of time. Full article

(This article belongs to the Special Issue Histories of Crops, between Niche Construction, Domestication and Diversification)

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17 pages, 3879 KiB

Open AccessEditor’s ChoiceArticle

Unraveling the Association between Metabolic Changes in Inter-Genus and Intra-Genus Bacteria to Mitigate Clubroot Disease of Chinese Cabbage

by Lanfang Wei, Jun Yang, Waqar Ahmed, Xinying Xiong, Qi Liu, Qiong Huang and Guanghai Ji

Agronomy 2021, 11(12), 2424; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122424 - 28 Nov 2021

Cited by 19 | Viewed by 2336

Abstract

Clubroot disease caused by the obligate parasite Plasmodiophora brassicae is a serious threat to cabbage production worldwide. Current clubroot control primarily relies on a fungicide, but this has a negative impact on the environment and the use of a single biocontrol agent cannot [...] Read more.

Clubroot disease caused by the obligate parasite Plasmodiophora brassicae is a serious threat to cabbage production worldwide. Current clubroot control primarily relies on a fungicide, but this has a negative impact on the environment and the use of a single biocontrol agent cannot efficiently control the disease. Thus, the combined application of different biocontrol agents has been proposed as a promising alternative. In this study, we used bacterial biocontrol agents as a co-culture (inter-genus and intra-genus) and mono-culture to mitigate the clubroot disease of Chinese cabbage. We evaluated their biocontrol effect and plant growth promoter (PGP) traits in in vitro and in vivo experiments. This study revealed that the inter-genus bacterial co-culture significantly suppresses the incidence of clubroot disease and enhances plant growth compared with intra-genus and mono-culture. In pairwise interaction, we observed that Bacillus cereus BT-23 promotes the growth of Lysobacter antibioticus 13-6 (inter-genus bacterial co-culture), whereas L. capsici ZST1-2 and L. antibioticus 13-6 (intra-genus microbial co-culture) are antagonists to each other. Furthermore, a total of 5575 metabolites, 732 differentially expressed metabolites (DEMs), and 510 unique metabolites were detected through the LC-MS/MS technique in the bacterial co-culture. The number of unique metabolites in inter-genus bacterial co-culture (393 metabolites) was significantly higher than in the intra-genus bacterial co-culture (117 metabolites). Further analysis of DEMs showed that the DEMs were mainly involved in four kinds of metabolism pathways, i.e., carbohydrate metabolism, amino metabolism, nucleotide metabolism, and metabolism of cofactors and vitamins. The contents of some secondary metabolites with biocontrol activity and plant growth-promoting functions were increased in inter-genus bacterial co-culture, indicating that inter-genus bacterial co-culture has a solid potential to suppress clubroot disease. We conclude that the inter-genus bacterial interaction changes the community metabolism and improves several secondary metabolites functions with respect to disease control and PGP ability. Full article

(This article belongs to the Special Issue Microbial Control of Crop Diseases: Limitations and Optimizations)

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15 pages, 2637 KiB

Open AccessEditor’s ChoiceArticle

Modern Short Food Supply Chain, Good Agricultural Practices, and Sustainability: A Conceptual Framework and Case Study in Vietnam

by Viet Hoang

Agronomy 2021, 11(12), 2408; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122408 - 26 Nov 2021

Cited by 16 | Viewed by 5608

Abstract

The rapid increases in environmental pollution, urbanization, health concerns, and technological progress enhance the demand for greener, healthier, and fairer food production and consumption. The short food supply chain (SFSC) becomes one of the crucial solutions for these issues. This study aims to [...] Read more.

The rapid increases in environmental pollution, urbanization, health concerns, and technological progress enhance the demand for greener, healthier, and fairer food production and consumption. The short food supply chain (SFSC) becomes one of the crucial solutions for these issues. This study aims to propose a conceptual framework of the SFSC, assess the short vegetable supply chain (SVSC) in Vietnam, identify its barriers and challenges, and explore interventions and support as key success factors of the SVSC by using both qualitative and quantitative methods. This study initially proposes the SFSC framework with six pillars and 28 indicators, this model is used to assess the SVSC. The results show that the SVSC brings various social, economic, and environmental benefits: First, it can increase farmers’ income, employment, fairness, and health. Second, the SVSC can decrease environmental pollution, food waste, and energy consumption. Third, it can improve food quality and consumers’ health. Fourth, the SVSC enhances on-farm education, agricultural tourism, local livestock farming, and traditional culture and relationship. However, the SVSC encounters various barriers and challenges impeding its performances and benefits. The vegetable value chain gains several interventions and support from the government and the project to overcome these barriers. Overall, the SFSC, good agricultural practice, and sustainability are strongly associated: good agricultural practice and sustainability are inherent in the SFSC. Full article

(This article belongs to the Special Issue Managing Agricultural Value Chains in a Rapidly Urbanizing World)

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20 pages, 1439 KiB

Open AccessEditor’s ChoiceArticle

Plant Disease Identification Using Shallow Convolutional Neural Network

by Sk Mahmudul Hassan, Michal Jasinski, Zbigniew Leonowicz, Elzbieta Jasinska and Arnab Kumar Maji

Agronomy 2021, 11(12), 2388; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122388 - 24 Nov 2021

Cited by 39 | Viewed by 4661

Abstract

Various plant diseases are major threats to agriculture. For timely control of different plant diseases in effective manner, automated identification of diseases are highly beneficial. So far, different techniques have been used to identify the diseases in plants. Deep learning is among the [...] Read more.

Various plant diseases are major threats to agriculture. For timely control of different plant diseases in effective manner, automated identification of diseases are highly beneficial. So far, different techniques have been used to identify the diseases in plants. Deep learning is among the most widely used techniques in recent times due to its impressive results. In this work, we have proposed two methods namely shallow VGG with RF and shallow VGG with Xgboost to identify the diseases. The proposed model is compared with other hand-crafted and deep learning-based approaches. The experiments are carried on three different plants namely corn, potato, and tomato. The considered diseases in corns are Blight, Common rust, and Gray leaf spot, diseases in potatoes are early blight and late blight, and tomato diseases are bacterial spot, early blight, and late blight. The result shows that our implemented shallow VGG with Xgboost model outperforms different deep learning models in terms of accuracy, precision, recall, f1-score, and specificity. Shallow Visual Geometric Group (VGG) with Xgboost gives the highest accuracy rate of 94.47% in corn, 98.74% in potato, and 93.91% in the tomato dataset. The models are also tested with field images of potato, corn, and tomato. Even in field image the average accuracy obtained using shallow VGG with Xgboost are 94.22%, 97.36%, and 93.14%, respectively. Full article

(This article belongs to the Special Issue Applications of Deep Learning in Smart Agriculture)

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20 pages, 3458 KiB

Open AccessEditor’s ChoiceArticle

Elevated Fe and Mn Concentrations in Groundwater in the Songnen Plain, Northeast China, and the Factors and Mechanisms Involved

by Yuanzheng Zhai, Xinyi Cao, Xuelian Xia, Bin Wang, Yanguo Teng and Xiao Li

Agronomy 2021, 11(12), 2392; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11122392 - 24 Nov 2021

Cited by 31 | Viewed by 2742

Abstract

Groundwater is an essential source of drinking and irrigation water. However, elevated Fe and Mn concentrations in groundwater have been found in recent decades, which can adversely affect human health and decrease crop quality and yields. The roles of hydrogeochemical changes and groundwater [...] Read more.

Groundwater is an essential source of drinking and irrigation water. However, elevated Fe and Mn concentrations in groundwater have been found in recent decades, which can adversely affect human health and decrease crop quality and yields. The roles of hydrogeochemical changes and groundwater pollution (exogenous reductive material inputs) in this have not been studied adequately. We determined the distribution of Fe and Mn concentrations in groundwater in the Songnen Plain, northeast China, which is known for elevated Fe and Mn concentrations, and investigated the factors and mechanisms involved in causing the elevated concentrations. Chemical and statistical analyses indicated that the Fe and Mn concentrations in groundwater significantly correlated with climate parameters (precipitation and temperature), surface features (altitude, distance from a river, soil type, soil texture, and land use type) and hydrogeochemical characteristics (chemical oxygen demand and NH₄⁺, NO₃⁻, and P concentrations). In particular, the Fe and Mn concentrations in groundwater are higher in areas containing paddy fields and water bodies than other land use type areas. Areas with groundwater containing ultra-high Fe and Mn concentrations have almost all of the favorable factors. The main reasons for the elevated Fe and Mn concentrations in groundwater in the study area are the Fe/Mn mineral-rich strata and soil with abundant organic matter acting as sources of Fe and Mn to the groundwater and the reductive environment in the lower terrain and areas containing water bodies favoring Fe and Mn dissolution in the groundwater. Inputs of pollutants from agricultural activities have caused the Fe and Mn concentrations in groundwater to increase. Future studies should be performed to study interactions between pollutants from agricultural activities and Fe and Mn in groundwater and develop environmental management strategies for preventing future increases in Fe and Mn concentrations and promoting sustainable development of agriculture. Full article

(This article belongs to the Special Issue Environmental Ecological Remediation and Farming Sustainability)

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16 pages, 5127 KiB

Open AccessEditor’s ChoiceArticle

Automated Muzzle Detection and Biometric Identification via Few-Shot Deep Transfer Learning of Mixed Breed Cattle

by Ali Shojaeipour, Greg Falzon, Paul Kwan, Nooshin Hadavi, Frances C. Cowley and David Paul

Agronomy 2021, 11(11), 2365; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112365 - 22 Nov 2021

Cited by 23 | Viewed by 8841

Abstract

Livestock welfare and management could be greatly enhanced by the replacement of branding or ear tagging with less invasive visual biometric identification methods. Biometric identification of cattle from muzzle patterns has previously indicated promising results. Significant barriers exist in the translation of these [...] Read more.

Livestock welfare and management could be greatly enhanced by the replacement of branding or ear tagging with less invasive visual biometric identification methods. Biometric identification of cattle from muzzle patterns has previously indicated promising results. Significant barriers exist in the translation of these initial findings into a practical precision livestock monitoring system, which can be deployed at scale for large herds. The objective of this study was to investigate and address key limitations to the autonomous biometric identification of cattle. The contributions of this work are fourfold: (1) provision of a large publicly-available dataset of cattle face images (300 individual cattle) to facilitate further research in this field, (2) development of a two-stage YOLOv3-ResNet50 algorithm that first detects and extracts the cattle muzzle region in images and then applies deep transfer learning for biometric identification, (3) evaluation of model performance across a range of cattle breeds, and (4) utilizing few-shot learning (five images per individual) to greatly reduce both the data collection requirements and duration of model training. Results indicated excellent model performance. Muzzle detection accuracy was 99.13% (1024 × 1024 image resolution) and biometric identification achieved 99.11% testing accuracy. Overall, the two-stage YOLOv3-ResNet50 algorithm proposed has substantial potential to form the foundation of a highly accurate automated cattle biometric identification system, which is applicable in livestock farming systems. The obtained results indicate that utilizing livestock biometric monitoring in an advanced manner for resource management at multiple scales of production is possible for future agriculture decision support systems, including providing useful information to forecast acceptable stocking rates of pastures. Full article

(This article belongs to the Special Issue Data-Driven Agricultural Innovations)

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15 pages, 10451 KiB

Open AccessEditor’s ChoiceArticle

Establishment and First Year Yield of Interseeded Alfalfa as Influenced by Corn Plant Density and Treatment with Prohexadione, Fungicide and Insecticide

by John H. Grabber, Damon L. Smith, William R. Osterholz and Mark J. Renz

Agronomy 2021, 11(11), 2343; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112343 - 19 Nov 2021

Cited by 5 | Viewed by 2421

Abstract

Interseeding alfalfa (Medicago sativa L.) into a silage corn (Zea mays L.) companion crop can increase the yield and profitability of forage production and reduce the risk of nutrient and soil loss from cropland, but unreliable establishment of alfalfa hampers the [...] Read more.

Interseeding alfalfa (Medicago sativa L.) into a silage corn (Zea mays L.) companion crop can increase the yield and profitability of forage production and reduce the risk of nutrient and soil loss from cropland, but unreliable establishment of alfalfa hampers the adoption of this practice on dairy farms. This study evaluated plant survival, foliar health, and dry matter yields of two alfalfa varieties when established in corn sown at populations ranging from about 47,500 to 100,000 plants per ha⁻¹ and when treated with prohexadione (PHD), PHD followed by fungicide and insecticide (PHD-FI), or not treated with agrichemicals. The plant density of alfalfa during establishment was adversely impacted by above average precipitation and high corn populations, but substantially improved by PHD-FI treatment, which limited alfalfa etiolation, disease, and defoliation. First-cut dry-matter yields of interseeded alfalfa after corn were maximized at a stand density of approximately 200 plants m⁻² or 850 stems m⁻² and total first year yield exceeded conventionally spring-seeded alfalfa by 59 to 75%. Overall, our results indicated that PHD-FI treatment promoted good establishment and subsequent forage production of interseeded alfalfa. Applications of PHD-FI must, however, be fine-tuned, and additional management practices must be developed to ensure both good yields of corn silage and reliable establishment of interseeded alfalfa, especially during wet growing conditions. Full article

(This article belongs to the Special Issue Multifunctional Forages)

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19 pages, 3296 KiB

Open AccessEditor’s ChoiceArticle

Effect of Spatial-Temporal Light Competition on Cotton Yield and Yield Distribution

by Qingru Wang, Huanxuan Chen, Yingchun Han, Fangfang Xing, Zhanbiao Wang, Lu Feng, Guoping Wang, Beifang Yang, Yaping Lei, Shiwu Xiong, Xiaofei Li, Minghua Xin, Wenli Du and Yabing Li

Agronomy 2021, 11(11), 2346; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112346 - 19 Nov 2021

Cited by 7 | Viewed by 2026

Abstract

The photosynthetically active radiation (PAR) of crop canopy is highly related to yield formation, but how it relates to yield and yield distribution is not well understood. The focus of this study was to explore the relationship between light competition under different densities [...] Read more.

The photosynthetically active radiation (PAR) of crop canopy is highly related to yield formation, but how it relates to yield and yield distribution is not well understood. The focus of this study was to explore the relationship between light competition under different densities and yield distributions of cotton. The experiment was conducted in 2019 and 2020 at the Cotton Research Institute of the Chinese Academy of Agricultural Sciences in Anyang city, Henan Province, China. A randomized block design was employed, with a total of three repeats. Each repeat had six density treatments: D1: 15,000; D2: 33,000; D3: 51,000; D4: 69,000; D5: 87,000; and D6: 105,000 plants·ha⁻¹. As predicted, the results showed that the canopy light interception, leaf area index, plant height, and biomass of high-density cotton were higher than those of low-density cotton. The aboveground biomass produced by D6 was the highest, and was 12.9, 19.5, 25.4, 46.3, and 69.2% higher in 2019 and 14.3, 19.9, 32.5, 53.7, and 109.9% higher in 2020 than D5, D4, D3, D2, and D1, respectively. Leaf area, plant height, biomass, boll number, and boll weight were significantly correlated with the light interception rate. D5 (87,000 plants·ha⁻¹) had a higher light interception rate and the highest yield. The highest lint yields produced by D5 were 1673.5 and 1375.4 kg·ha⁻¹ in two years, and was 3.2, 4.3, 5.6, 9.7, and 24.7% higher in 2019, and 6.8, 10.6, 13.5, 21.5, and 34.4% higher in 2020 than D6, D4, D3, D2, and D1, respectively. The boll retention of the lower fruit branch under D5 reached 0.51 and 0.57 in two years, respectively. The shedding rate of the upper fruit branch decreased with the increase in cotton density in two years. The boll retention rate and shedding rate in the lower part of cotton plants were most closely related to light interception, with R² values of 0.91 and 0.96, respectively. Our study shows cotton yield could be improved through higher light interception by optimizing planting density and canopy structure. Full article

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19 pages, 5028 KiB

Open AccessEditor’s ChoiceArticle

Key Cannabis Salt-Responsive Genes and Pathways Revealed by Comparative Transcriptome and Physiological Analyses of Contrasting Varieties

by Jiangjiang Zhang, Cuiping Zhang, Siqi Huang, Li Chang, Jianjun Li, Huijuan Tang, Susmita Dey, Ashok Biswas, Dengxiang Du, Defang Li and Lining Zhao

Agronomy 2021, 11(11), 2338; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112338 - 19 Nov 2021

Cited by 7 | Viewed by 3213

Abstract

For the dissection and identification of the molecular response mechanisms to salt stress in cannabis, an experiment was conducted surveying the diversity of physiological characteristics. RNA-seq profiling was carried out to identify differential expression genes and pathway which respond to salt stress in [...] Read more.

For the dissection and identification of the molecular response mechanisms to salt stress in cannabis, an experiment was conducted surveying the diversity of physiological characteristics. RNA-seq profiling was carried out to identify differential expression genes and pathway which respond to salt stress in different cannabis materials. The result of physiological diversity analyses showed that it is more sensitive to proline contents in K94 than in W20; 6 h was needed to reach the maximum in K94, compared to 12 h in W20. For profiling 0–72 h after treatment, a total of 10,149 differentially expressed genes were identified, and 249 genes exhibited significantly diverse expression levels in K94, which were clustered in plant hormone signal transduction and the MAPK signaling pathway. A total of 371 genes showed significant diversity expression variations in W20, which were clustered in the phenylpropanoid biosynthesis and plant hormone signal transduction pathway. The pathway enrichment by genes which were identified in K94 and W20 showed a similar trend to those clustered in plant hormone signal transduction pathways and MAPK signaling. Otherwise, there were 85 genes which identified overlaps between the two materials, indicating that these may be underlying genes related to salt stress in cannabis. The 86.67% agreement of the RNA-seq and qRT-PCR indicated the accuracy and reliability of the RNA-seq technique. Additionally, the result of physiological diversity was consistent with the predicted RNA-seq-based findings. This research may offer new insights into the molecular networks mediating cannabis to respond to salt stress. Full article

(This article belongs to the Topic Physiological and Molecular Characterization of Crop Tolerance to Abiotic Stresses)

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13 pages, 2171 KiB

Open AccessEditor’s ChoiceArticle

Estimation of Evapotranspiration and Crop Coefficient of Rain-Fed Tea Plants under a Subtropical Climate

by Shenghong Zheng, Kang Ni, Lingfei Ji, Chenguang Zhao, Hongling Chai, Xiaoyun Yi, Weizhong He and Jianyun Ruan

Agronomy 2021, 11(11), 2332; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112332 - 18 Nov 2021

Cited by 8 | Viewed by 2656

Abstract

Crop coefficient (K_c) is one of the most significant parameters for crop water demand prediction and irrigation scheduling. However, there is a lack of knowledge about water vapor and K_c in tea plantation ecosystems. This study explored and determined the [...] Read more.

Crop coefficient (K_c) is one of the most significant parameters for crop water demand prediction and irrigation scheduling. However, there is a lack of knowledge about water vapor and K_c in tea plantation ecosystems. This study explored and determined the actual evapotranspiration (ET_c) and K_c of two cultivars of tea (Camellia sinensis), clone variety Baiye1 (BY1) and Longjing43 (LJ43), based on lysimeter data. An estimation was made for both for ET_c and adjusted ET_c, and the corresponding K_c and adjusted K_c. The results showed that the adjusted ET_c and K_c values revealed a minor fluctuation when compared to the ET_c and K_c values during the experimental period, which indicated that the adjusted ET_c and K_c values were more precise and practical to field conditions. The average adjusted K_c values were 0.71 (range of 0.43–1.02) for BY1 and 0.84 (range of 0.48–1.22) for LJ43. Additionally, heavy pruning can decrease ET_c and K_c values, possibly due to the lower level of LAI after pruning. Moreover, it is clearly manifested that BY1 consistently had lower ET_c and K_c values than those of LJ43 because of plant growth status differences between BY1 and LJ43. Overall, our study proposed a reliable reference of K_c in tea plantation, and illuminated the effects of pruning and plant growth differences on K_c, which could provide a strong basis for precise irrigation in tea plantations in a subtropical climate. Full article

(This article belongs to the Special Issue Agroecology and Organic Horticulture)

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13 pages, 2422 KiB

Open AccessEditor’s ChoiceArticle

Interactive Effects of Foliar Application of Zinc, Iron and Nitrogen on Productivity and Nutritional Quality of Indian Mustard (Brassica juncea L.)

by Salwinder Singh Dhaliwal, Vivek Sharma, Arvind Kumar Shukla, Vibha Verma, Prabhjodh Singh Sandhu, Sanjib K. Behera, Prabhjot Singh, Janpriya Kaur, Harkirat Singh, Shams H. Abdel-Hafez, Ahmed Gaber, Samy Sayed and Akbar Hossain

Agronomy 2021, 11(11), 2333; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112333 - 18 Nov 2021

Cited by 15 | Viewed by 3833

Abstract

Indian mustard (Brassica juncea L.) is an important winter oilseed crop in India. It acts as a promising species for the extraction of Zn and Fe under nutrient-deficit conditions. Therefore, this study planned to determine the impact of nutritional supplementation (Zn, Fe [...] Read more.

Indian mustard (Brassica juncea L.) is an important winter oilseed crop in India. It acts as a promising species for the extraction of Zn and Fe under nutrient-deficit conditions. Therefore, this study planned to determine the impact of nutritional supplementation (Zn, Fe and urea) on the productivity and nutritional quality of Indian mustard. In the experiment, different combinations of recommended dose of fertilizer (RDF) with 0.5% FeSO₄·7H₂O, 0.5% ZnSO₄·7H₂O and 1% urea at 45 and 60 days after sowing (DAS) were applied to Indian mustard. Foliar application of micronutrients along with urea enhanced the productivity and quality of the crop. Among different treatments, the foliar application of 0.5% FeSO₄·7H₂O + 0.5% ZnSO₄·7H₂O + 1% urea (FZU) at 45 and 60 DAS resulted in the maximum increase in grain (27.8%) and stover (34.47%) yield, which was statistically at par with the treatment 0.5% FeSO₄·7H₂O + 0.5% ZnSO₄·7H₂O at 45 and 60 DAS (FZ). A similar trend was observed for Zn concentration in grain and stover, as well as Fe concentration in stover. However, the Fe concentration in grain was at maximum with treatment FZU, and the results were significantly higher compared with the treatment FZ. Treatment FZU also resulted in a maximum increase in Zn and Fe uptake in grain (54.7% and 34.3%, respectively) and stover (110.5% and 46.1%, respectively), which was statistically at par with treatment FZ. Physiological efficiencies of Zn (11,838.33) and Fe (3575.887) were highest when only urea was applied along with RDF, whereas the apparent recovery efficiency of Zn and Fe was highest in treatment FZU. Overall, it is concluded that combined foliar application of, 0.5% FeSO₄·7H₂O + 0.5% ZnSO₄·7H₂O + 1% urea at 45 and 60 DAS along with RDF was found to be most effective to enhance yield, concentration and uptake of Zn and Fe in Indian mustard. Full article

(This article belongs to the Special Issue Development and Efficiency of New Micronutrient Fertilizers)

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16 pages, 1816 KiB

Open AccessEditor’s ChoiceArticle

Modelling the Effect and Variability of Integrated Weed Management of Phalaris minor in Rice-Wheat Cropping Systems in Northern India

by Chun Liu, Makhan Singh Bhullar, Tarundeep Kaur, Jitendra Kumar, Sriyapu Reddy Sreekanth Reddy, Manpreet Singh and Shiv Shankhar Kaundun

Agronomy 2021, 11(11), 2331; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112331 - 18 Nov 2021

Cited by 1 | Viewed by 1994

Abstract

Phalaris minor Retz. (littleseed canarygrass) is the most problematic and herbicide-resistant weed in the rice-wheat cropping system in India. As such, it poses a severe threat to wheat yield and food security. A number of herbicidal and agronomic practices have been identified for [...] Read more.

Phalaris minor Retz. (littleseed canarygrass) is the most problematic and herbicide-resistant weed in the rice-wheat cropping system in India. As such, it poses a severe threat to wheat yield and food security. A number of herbicidal and agronomic practices have been identified for the effective control of P. minor. These include crop rotation, crop establishment methods, herbicide spray technology, sowing time, weed seed harvest and effective herbicide mixtures. A population model of P. minor was built based on the life cycle of the species, herbicide resistance mechanisms and the effects of weed control practices. The model simulated the interactions of these factors and provided the best management recommendations for sustainably controlling this noxious weed species. Model results indicate that integration of chemical and non-chemical control methods was the most effective and sustainable strategy. For example, the integration of a happy seeder (a tractor-mounted mulching and sowing machine) with an effective post-emergence herbicide reduced the probability of weed control failure by 32% compared to the scenario with a rotavator and the same herbicide. Similarly, more conventional crop establishment methods such as a rotavator and conventional tillage could be accompanied by pre- or post-emergence applications of herbicide mixtures. Adoption of good herbicide spray technology and weed seed harvest delayed the onset of resistance evolution by up to four years. Furthermore, effective crop rotation such as the inclusion of sugarcane in place of rice in the summer season reduced the risk of resistance evolution by 31% within the 10 year simulation period. In addition to the scenarios using representative parameter values, the variability of model predictions was investigated based on some field experiments. The model provided a powerful tool for promoting Integrated Weed Management and the sustainable use of herbicides. Pragmatic ways of dealing with uncertainty in model prediction are discussed. Full article

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12 pages, 9865 KiB

Open AccessEditor’s ChoiceArticle

Effect of Nitrogen Supply on Growth and Nitrogen Utilization in Hemp (Cannabis sativa L.)

by Yang Yang, Wenxin Zha, Kailei Tang, Gang Deng, Guanghui Du and Feihu Liu

Agronomy 2021, 11(11), 2310; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112310 - 15 Nov 2021

Cited by 9 | Viewed by 3281

Abstract

Hemp is a multipurpose crop that is cultivated worldwide for fiber, oil, and cannabinoids. Nitrogen (N) is a key factor for getting a higher production of hemp, but its application is often excessive and results in considerable losses in the soil–plant–water continuum. Therefore, [...] Read more.

Hemp is a multipurpose crop that is cultivated worldwide for fiber, oil, and cannabinoids. Nitrogen (N) is a key factor for getting a higher production of hemp, but its application is often excessive and results in considerable losses in the soil–plant–water continuum. Therefore, a rational N supply is important for increasing N efficiency and crop productivity. The main objective of this paper was to determine the responses of four hemp cultivars to different levels of exogenous-N supply as nutrient solution during the vegetative growing period. The experiment was conducted at Yunnan University in Kunming, China. Yunma 1, Yunma 7, Bamahuoma, and Wanma 1 were used as the experimental materials, and five N supplying levels (1.5, 3.0, 6.0, 12.0, and 24.0 mmol/L NO₃-N in the nutrient solution) were set by using pot culture and adding nutrient solution. The root, stem, and leaf of the plant were sampled for the determination of growth indexes, dry matter and N accumulation and distribution, and physiological indicators. The plant height, stem diameter, plant dry weight, and plant N accumulation of four hemp cultivars were significantly increased with the increase in exogenous-N supply. Root/shoot dry weight ratios, stem mass density, and N use efficiency decreased significantly with the increase in exogenous-N supply. Nitrogen accumulation, chlorophyll content, soluble protein content, and nitrate reductase activity in leaves were increased with the increase in exogenous-N supply. Among the four indexes, the increase in N accumulation was more than the increase in NR activity. The activities of superoxide dismutase and peroxidase in leaves were increased first and then decreased with the increase in exogenous-N supply, with the maximum value at N 6.0 mmol/L, while the content of malondialdehyde in leaves increased significantly when the level of exogenous-N supply exceeded 6.0 mmol/L. These results revealed that increasing the exogenous-N supply could improve the plant growth, dry matter accumulation, and N accumulation in hemp during the vegetative growth period, but N supply should not exceed 6.0 mmol/L. Among four hemp cultivars, Wanma 1 performed well at 6.0 mmol/L N application. Full article

(This article belongs to the Special Issue Crop Nutrient Requirements and Advanced Fertilizer Management Strategies)

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15 pages, 1543 KiB

Open AccessEditor’s ChoiceArticle

Impact of Corn Cob-Derived Biochar in Altering Soil Quality, Biochemical Status and Improving Maize Growth under Drought Stress

by Liaqat Ali, Natasha Manzoor, Xuqing Li, Muhammad Naveed, Sajid Mahmood Nadeem, Muhammad Rashid Waqas, Muhammad Khalid, Aown Abbas, Temoor Ahmed, Bin Li and Jianli Yan

Agronomy 2021, 11(11), 2300; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112300 - 13 Nov 2021

Cited by 21 | Viewed by 4852

Abstract

Biochar enhances soil fertility by improving the soil physical, chemical and microbiological properties. The aim of this study was to investigate the impact of corn cob-derived biochar on soil enzymatic activity, organic carbon, aggregate stability and soil microbial biomass carbon under drought stress. [...] Read more.

Biochar enhances soil fertility by improving the soil physical, chemical and microbiological properties. The aim of this study was to investigate the impact of corn cob-derived biochar on soil enzymatic activity, organic carbon, aggregate stability and soil microbial biomass carbon under drought stress. Biochar was prepared from crushed corn cobs pyrolyzed at 300 °C and 400 °C and applied at a ratio of 1% (w/w) and 3% (w/w) filled in pots. In each pot, three field capacity (FC) levels, i.e., 100, 70 and 40%, were maintained gravimetrically. Results showed that biochar application improved the growth (plant height and root length) and relative water content in maize leaves under drought stress, while it reduced electrolyte leakage compared to a control treatment. Aggregate stability was significantly (p ≤ 0.05) higher in biochar amended soil. Moreover, microbial biomass carbon and soil water also increased under drought stress at 70% FC and 40% FC, respectively, where 3% w/w (400 °C) biochar was applied. Among enzymes, β-glucosidase and alkaline phosphatase activity were improved with biochar application. The maximum organic carbon (240%, 246% and 249%, 254% more than control) was calculated in soils where 3% biochar pyrolyzed at 400 °C and 300 °C was mixed with soil, respectively. Similarly, the carbon pool index (CPI) and carbon management index (CMI) were also higher in biochar-amended soil as compared to control treatment. Conclusively, biochar amendment could effectively improve soil quality and maize growth under drought stress. Full article

(This article belongs to the Special Issue Plant, Soil, Microbe Interactions in Response to Environmental Stress)

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16 pages, 965 KiB

Open AccessEditor’s ChoiceArticle

The Segmented Colour Feature Extreme Learning Machine: Applications in Agricultural Robotics

by Edmund J. Sadgrove, Greg Falzon, David Miron and David W. Lamb

Agronomy 2021, 11(11), 2290; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112290 - 12 Nov 2021

Cited by 5 | Viewed by 2134

Abstract

This study presents the Segmented Colour Feature Extreme Learning Machine (SCF-ELM). The SCF-ELM is inspired by the Extreme Learning Machine (ELM) which is known for its rapid training and inference times. The ELM is therefore an ideal candidate for an ensemble learning algorithm. [...] Read more.

This study presents the Segmented Colour Feature Extreme Learning Machine (SCF-ELM). The SCF-ELM is inspired by the Extreme Learning Machine (ELM) which is known for its rapid training and inference times. The ELM is therefore an ideal candidate for an ensemble learning algorithm. The Colour Feature Extreme Learning Machine (CF-ELM) is used in this study due to its additional ability to extract colour image features. The SCF-ELM is an ensemble learner that utilizes feature mapping via k-means clustering, a decision matrix and majority voting. It has been evaluated on a range of challenging agricultural object classification scenarios including weed, livestock and machinery detection. SCF-ELM model performance results were excellent both in terms of detection, 90 to 99% accuracy, and also inference times, around 0.01(s) per image. The SCF-ELM was able to compete or improve upon established algorithms in its class, indicating its potential for remote computing applications in agriculture. Full article

(This article belongs to the Special Issue Data-Driven Agricultural Innovations)

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23 pages, 2400 KiB

Open AccessEditor’s ChoiceArticle

Crop Wild Relatives Crosses: Multi-Location Assessment in Durum Wheat, Barley, and Lentil

by Noureddine El Haddad, Miguel Sanchez-Garcia, Andrea Visioni, Abderrazek Jilal, Rola El Amil, Amadou Tidiane Sall, Wasihun Lagesse, Shiv Kumar and Filippo M. Bassi

Agronomy 2021, 11(11), 2283; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112283 - 11 Nov 2021

Cited by 17 | Viewed by 3890

Abstract

Crop wild relatives (CWR) are a good source of useful alleles for climate change adaptation. Here, 19 durum wheat, 24 barley, and 24 lentil elites incorporating CWR in their pedigrees were yield tested against commercial checks across 19 environments located in Morocco, Ethiopia, [...] Read more.

Crop wild relatives (CWR) are a good source of useful alleles for climate change adaptation. Here, 19 durum wheat, 24 barley, and 24 lentil elites incorporating CWR in their pedigrees were yield tested against commercial checks across 19 environments located in Morocco, Ethiopia, Lebanon, and Senegal. For each crop, the combined analysis of variance showed that genotype (G), environment (E), and genotype x environment (G×E) effects were significant for most of the traits. A selection index combining yield potential (G) and yield stability (G×E) was used to identify six CWR-derived elites for each crop matching or superior to the best check. A regression analysis using a climate matrix revealed that grain yield was mostly influenced by the maximum daily temperature and soil moisture level during the growing stages. These climatic factors were used to define five clusters (i.e., E1 to E5) of mega-environments. The CWR-derived elites significantly outperformed the checks in E1, E2, and E4 for durum wheat, and in E2 for both barley and lentil. The germplasm was also assessed for several food transformation characteristics. For durum wheat, one accession (Zeina) originating from T. araraticum was significantly superior in mixograph score to the best check, and three accessions originating from T. araraticum and T. urartu were superior for Zn concentration. For barley, 21 accessions originating from H. spontaneum were superior to the checks for protein content, six for Zn content, and eight for β-glucan. For lentil, ten accessions originating from Lens orientalis were superior to the check for protein content, five for Zn, and ten for Fe concentration. Hence, the results presented here strongly support the use of CWR in breeding programs of these three dryland crops, both for adaptation to climatic stresses and for value addition for food transformation. Full article

(This article belongs to the Special Issue Utilizing Genetic Resources for Agronomic Traits Improvement)

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22 pages, 5923 KiB

Open AccessEditor’s ChoiceArticle

Coffee Rust Forecast Systems: Development of a Warning Platform in a Minas Gerais State, Brazil

by Edson Ampélio Pozza, Éder Ribeiro dos Santos, Nilva Alice Gaspar, Ximena Maira de Souza Vilela, Marcelo de Carvalho Alves and Mário Roberto Nogueira Colares

Agronomy 2021, 11(11), 2284; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112284 - 11 Nov 2021

Cited by 2 | Viewed by 3303

Abstract

This study aimed to develop a warning system platform for coffee rust incidence fifteen days in advance, as well as validating and regionalizing multiple linear regression models based on meteorological variables. The models developed by Pinto were validated in five counties. Experiments were [...] Read more.

This study aimed to develop a warning system platform for coffee rust incidence fifteen days in advance, as well as validating and regionalizing multiple linear regression models based on meteorological variables. The models developed by Pinto were validated in five counties. Experiments were set up in a randomized block design with five treatments and five replications. The experimental plot had six lines with 20 central plants of useful area. Assessments of coffee rust incidence were carried out fortnightly. The data collected from automatic stations were adjusted in new multiple linear regression models (MLRM) for five counties. Meteorological variables were lagged concerning disease assessment dates. After the adjustments, two models were selected and calculated for five counties, later there was an expansion to include ten more counties and 35 properties to validate these models. The result showed that the adjusted models of 15–30 days before rust incidence for Carmo do Rio Claro and Nova Resende counties were promising. These models were the best at forecasting disease 15 days in advance. With these models and the geoinformation systems, the warning platform and interface will be improved in the coffee grower region of the south and savannas of the Minas Gerais State, Brazil. Full article

(This article belongs to the Special Issue Current Status and Management of Coffee Rust Disease)

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24 pages, 5280 KiB

Open AccessEditor’s ChoiceArticle

A Multi-Objective Particle Swarm Optimization for Trajectory Planning of Fruit Picking Manipulator

by Xiaoman Cao, Hansheng Yan, Zhengyan Huang, Si Ai, Yongjun Xu, Renxuan Fu and Xiangjun Zou

Agronomy 2021, 11(11), 2286; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112286 - 11 Nov 2021

Cited by 33 | Viewed by 3750

Abstract

Stable, efficient and lossless fruit picking has always been a difficult problem, perplexing the development of fruit automatic picking technology. In order to effectively solve this technical problem, this paper establishes a multi-objective trajectory model of the manipulator and proposes an improved multi-objective [...] Read more.

Stable, efficient and lossless fruit picking has always been a difficult problem, perplexing the development of fruit automatic picking technology. In order to effectively solve this technical problem, this paper establishes a multi-objective trajectory model of the manipulator and proposes an improved multi-objective particle swarm optimization algorithm (represented as GMOPSO). The algorithm combines the methods of mutation operator, annealing factor and feedback mechanism to improve the diversity of the population on the basis of meeting the stable motion, avoiding the local optimal solution and accelerating the convergence speed. By adopting the average optimal evaluation method, the robot arm motion trajectory has been testified to constructively fulfill the picking standards of stability, efficiency and lossless. The performance of the algorithm is verified by ZDT1~ZDT3 benchmark functions, and its competitive advantages and disadvantages with other multi-objective evolutionary algorithms are further elaborated. In this paper, the algorithm is simulated and verified by practical experiments with the optimization objectives of time, energy consumption and pulsation. The simulation results show that the solution set of the algorithm is close to the real Pareto frontier. The optimal solution obtained by the average optimal evaluation method is as follows: the time is 34.20 s, the energy consumption is 61.89 °/S2 and the pulsation is 72.18 °/S3. The actual test results show that the trajectory can effectively complete fruit picking, the average picking time is 25.5 s, and the success rate is 96.67%. The experimental results show that the trajectory of the manipulator obtained by GMOPSO algorithm can make the manipulator run smoothly and facilitates efficient, stable and nondestructive picking. Full article

(This article belongs to the Collection Advances of Agricultural Robotics in Sustainable Agriculture 4.0)

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17 pages, 1409 KiB

Open AccessEditor’s ChoiceArticle

Coupling Remote Sensing Data and AquaCrop Model for Simulation of Winter Wheat Growth under Rainfed and Irrigated Conditions in a Mediterranean Environment

by Marie Therese Abi Saab, Razane El Alam, Ihab Jomaa, Sleiman Skaf, Salim Fahed, Rossella Albrizio and Mladen Todorovic

Agronomy 2021, 11(11), 2265; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112265 - 9 Nov 2021

Cited by 16 | Viewed by 3234

Abstract

The coupling of remote sensing technology and crop growth models represents a promising approach to support crop yield prediction and irrigation management. In this study, five vegetation indices were derived from the Copernicus-Sentinel 2 satellite to investigate their performance monitoring winter wheat growth [...] Read more.

The coupling of remote sensing technology and crop growth models represents a promising approach to support crop yield prediction and irrigation management. In this study, five vegetation indices were derived from the Copernicus-Sentinel 2 satellite to investigate their performance monitoring winter wheat growth in a Mediterranean environment in Lebanon’s Bekaa Valley. Among those indices, the fraction of canopy cover was integrated into the AquaCrop model to simulate biomass and yield of wheat grown under rainfed conditions and fully irrigated regimes. The experiment was conducted during three consecutive growing seasons (from 2017 to 2019), characterized by different precipitation patterns. The AquaCrop model was calibrated and validated for different water regimes, and its performance was tested when coupled with remote sensing canopy cover. The results showed a good fit between measured canopy cover and Leaf Area Index (LAI) data and those derived from Sentinel 2 images. The R² coefficient was 0.79 for canopy cover and 0.77 for LAI. Moreover, the regressions were fitted to relate biomass with Sentinel 2 vegetation indices. In descending order of R², the indices were ranked: Fractional Vegetation Cover (FVC), LAI, the fraction of Absorbed Photosynthetically Active Radiation (fAPAR), the Normalized Difference Vegetation Index (NDVI), and the Enhanced Vegetation Index (EVI). Notably, FVC and LAI were highly correlated with biomass. The results of the AquaCrop calibration showed that the modeling efficiency values, NSE, were 0.99 for well-watered treatments and 0.95 for rainfed conditions, confirming the goodness of fit between measured and simulated values. The validation results confirmed that the simulated yield varied from 2.59 to 5.36 t ha⁻¹, while the measured yield varied from 3.08 to 5.63 t ha⁻¹ for full irrigation and rainfed treatments. After integrating the canopy cover into AquaCrop, the % of deviation of simulated and measured variables was reduced. The Root Mean Square Error (RMSE) for yield ranged between 0.08 and 0.69 t ha⁻¹ before coupling and between 0.04 and 0.42 t ha⁻¹ after integration. This result confirmed that the presented integration framework represents a promising method to improve the prediction of wheat crop growth in Mediterranean areas. Further studies are needed before being applied on a larger scale. Full article

(This article belongs to the Topic Eco-Sustainable Innovative Approaches for Water-Soil-Nutrient-Crop Management)

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18 pages, 5959 KiB

Open AccessEditor’s ChoiceArticle

Effects of Deficit Irrigation Scheduling on Water Use, Gas Exchange, Yield, and Fruit Quality of Date Palm

by Maged Mohammed, Abdelkader Sallam, Muhammad Munir and Hassan Ali-Dinar

Agronomy 2021, 11(11), 2256; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112256 - 8 Nov 2021

Cited by 15 | Viewed by 2977

Abstract

Water scarcity is very common in the arid region due to the low yearly rainfall. The cost of water for agricultural usage is extremely high in dry locations. Date palm is a high water-demanding tree throughout the year in arid regions. Therefore, the [...] Read more.

Water scarcity is very common in the arid region due to the low yearly rainfall. The cost of water for agricultural usage is extremely high in dry locations. Date palm is a high water-demanding tree throughout the year in arid regions. Therefore, the application of deficit irrigation strategies for date palm cultivation may significantly contribute to conserving irrigation water. The present study aimed to assess the effects of controlled deficit irrigation using two modern micro-irrigation systems on water use efficiency (WUE), gas exchange, fruit yield, and quality of date palm (Khalas cv.). The irrigation systems included drip irrigation (DI) and subsurface irrigation (SI) systems. The study was conducted during the 2020 and 2021 seasons at the Date Palm Research Center of Excellence, King Faisal University, Saudi Arabia. The meteorological variables of the study area were real-time monitored using cloud-based IoT (Internet of Things) to calculate the evapotranspiration reference (ETo) and control the irrigation scheduling. Three irrigation treatments (50, 75, and 100% ETc) were applied using DI and SI systems compared with the traditional surface bubbler irrigation (Control). The actual applied water at the deficit irrigation treatments of 50, 75, and 100% ETc were 27.28 ± 0.06, 44.14 ± 1.07, and 55.55 ± 0.37 m³ palm⁻¹, respectively. At all deficit irrigation treatments, the leaf chlorophyll and gas exchange were significantly higher in the SI compared to the DI system. The yield of date palms did not differ significantly between the control and SI systems at both the level of 100 and 75% ETc. The WUE under the SI (1.09 kg m⁻³) was significantly higher than the DI system (0.52 kg m⁻³) at the 50% level. There was no significant difference regarding the fruit quality parameters between SI at 50% ETc and control at 100% ETc. Therefore, adopting deficit irrigation strategies using the SI system at 50% ETc level throughout the year could be suggested for date palm irrigation to save water, improve WUE, and maintain fruit quality. Full article

(This article belongs to the Special Issue Woody Crop Responses to Water Shortage: Impacts on Plant Physiology, Yield and Fruit Composition)

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27 pages, 1407 KiB

Open AccessEditor’s ChoiceArticle

Understanding the Impact of Drought in Coffea Genotypes: Transcriptomic Analysis Supports a Common High Resilience to Moderate Water Deficit but a Genotype Dependent Sensitivity to Severe Water Deficit

by Isabel Fernandes, Isabel Marques, Octávio S. Paulo, Dora Batista, Fábio L. Partelli, Fernando C. Lidon, Fábio M. DaMatta, José C. Ramalho and Ana I. Ribeiro-Barros

Agronomy 2021, 11(11), 2255; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112255 - 8 Nov 2021

Cited by 21 | Viewed by 2757

Abstract

Water scarcity is the most significant factor limiting coffee production, although some cultivars can still have important drought tolerance. This study analyzed leaf transcriptomes of two coffee cultivars with contrasting physiological responses, Coffea canephora cv. CL153 and Coffea. arabica cv. Icatu, subjected to [...] Read more.

Water scarcity is the most significant factor limiting coffee production, although some cultivars can still have important drought tolerance. This study analyzed leaf transcriptomes of two coffee cultivars with contrasting physiological responses, Coffea canephora cv. CL153 and Coffea. arabica cv. Icatu, subjected to moderate (MWD) or severe water deficits (SWD). We found that MWD had a low impact compared with SWD, where 10% of all genes in Icatu and 17% in CL153 reacted to drought, being mainly down-regulated upon stress. Drought triggered a genotype-specific response involving the up-regulation of reticuline oxidase genes in CL153 and heat shock proteins in Icatu. Responsiveness to drought also included desiccation protectant genes, but primarily, aspartic proteases, especially in CL153. A total of 83 Transcription Factors were found engaged in response to drought, mainly up-regulated, especially under SWD. Together with the enrollment of 49 phosphatases and 272 protein kinases, results suggest the involvement of ABA-signaling processes in drought acclimation. The integration of these findings with complementing physiological and biochemical studies reveals that both genotypes are more resilient to moderate drought than previously thought and suggests the existence of post-transcriptional mechanisms modulating the response to drought. Full article

(This article belongs to the Special Issue Untapping the Potential of Neglected and Underutilized Species to Improve Food Security)

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14 pages, 8779 KiB

Open AccessEditor’s ChoiceArticle

Development of Monitoring Robot System for Tomato Fruits in Hydroponic Greenhouses

by Dasom Seo, Byeong-Hyo Cho and Kyoung-Chul Kim

Agronomy 2021, 11(11), 2211; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112211 - 31 Oct 2021

Cited by 33 | Viewed by 5023

Abstract

Crop monitoring is highly important in terms of the efficient and stable performance of tasks such as planting, spraying, and harvesting, and for this reason, several studies are being conducted to develop and improve crop monitoring robots. In addition, the applications of deep [...] Read more.

Crop monitoring is highly important in terms of the efficient and stable performance of tasks such as planting, spraying, and harvesting, and for this reason, several studies are being conducted to develop and improve crop monitoring robots. In addition, the applications of deep learning algorithms are increasing in the development of agricultural robots since deep learning algorithms that use convolutional neural networks have been proven to show outstanding performance in image classification, segmentation, and object detection. However, most of these applications are focused on the development of harvesting robots, and thus, there are only a few studies that improve and develop monitoring robots through the use of deep learning. For this reason, we aimed to develop a real-time robot monitoring system for the generative growth of tomatoes. The presented method detects tomato fruits grown in hydroponic greenhouses using the Faster R-CNN (region-based convolutional neural network). In addition, we sought to select a color model that was robust to external light, and we used hue values to develop an image-based maturity standard for tomato fruits; furthermore, the developed maturity standard was verified through comparison with expert classification. Finally, the number of tomatoes was counted using a centroid-based tracking algorithm. We trained the detection model using an open dataset and tested the whole system in real-time in a hydroponic greenhouse. A total of 53 tomato fruits were used to verify the developed system, and the developed system achieved 88.6% detection accuracy when completely obscured fruits not captured by the camera were included. When excluding obscured fruits, the system’s accuracy was 90.2%. For the maturity classification, we conducted qualitative evaluations with the assistance of experts. Full article

(This article belongs to the Special Issue Application of Computer Vision on Quality Monitoring of Agricultural Products)

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15 pages, 1317 KiB

Open AccessEditor’s ChoiceArticle

Labile Soil Organic Matter Pools Are Influenced by 45 Years of Applied Farmyard Manure and Mineral Nitrogen in the Wheat—Pearl Millet Cropping System in the Sub-Tropical Condition

by Ranjan Laik, B. H. Kumara, Biswajit Pramanick, Santosh Kumar Singh, Nidhi, Majid Alhomrani, Ahmed Gaber and Akbar Hossain

Agronomy 2021, 11(11), 2190; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112190 - 29 Oct 2021

Cited by 30 | Viewed by 1993

Abstract

Labile soil organic matter pools (LSOMp) are believed to be the most sensitive indicator of soil quality when it is changed rapidly with varied management practices. In sub-tropical climates, the turnover period of labile pools is quicker than in temperate climates. Organic amendments [...] Read more.

Labile soil organic matter pools (LSOMp) are believed to be the most sensitive indicator of soil quality when it is changed rapidly with varied management practices. In sub-tropical climates, the turnover period of labile pools is quicker than in temperate climates. Organic amendments are of importance in improve the LSOMp for a temperate climate and may be helpful in sub-tropical climates as well. Hence, the status of LSOMp was studied in long term farmyard manure (FYM) amended soils under wheat (Triticum aestivum L.) and pearl millet (Pennisetum glaucum L.) cropping systems in sub-tropical arid conditions. At the same time, we also attempt to determine the impact of mineral nitrogen (N) application in these pools. In this study, dissolved organic matter (DOM), microbial biomass (MB), and light fraction (LF) were isolated in the management practices involving different modes and rates of FYM applications along with the application of nitrogenous fertilizer. C and N contents of the labile pools were analyzed in the soil samples at different periods after FYM applications. Among the different pools, microbial biomass carbon (MBC) and dissolved organic carbon (DOC) were changed significantly with different rates and modes of FYM application and mineral N application. Application of FYM at 15 Mg ha⁻¹ in both the seasons + 120 kg ha⁻¹ mineral N resulted in significantly higher MBC and DOC as compared to all of the other treatments. This treatment also resulted in 13.75% and 5.8% more MBC and DOC, respectively, as compared to the amount of MBC and DOC content in the control plot where FYM and mineral N were not applied. Comparing the labile organic matter pools of 45 years of FYM amendment with initial values, it was found that the dissolved organic carbon, microbial biomass carbon, and light fraction carbon were increased up to the maximum extent of about 600, 1200, and 700 times, respectively. The maximum amount of DOM (562 mg kg⁻¹ of DOC and 70.1 mg kg⁻¹ of DON), MB (999 mg kg⁻¹ of MBC and 158.4 mg kg⁻¹ of MBN), LF (2.61 g kg⁻¹ of LFC and 154.6 g kg⁻¹ of LFN) were found in case of both season applied FYM as compared to either summer or winter applied FYM. Concerning the different rates of FYM application, 15 Mg ha⁻¹ FYM also resulted in a significantly higher amount of DOM, MB, and LF as compared to other FYM rates (i.e., 5 Mg ha⁻¹ and 10 Mg ha⁻¹). Amongst different pools, MB was found to be the most sensitive to management practices in this study. From this study, it was found that the long-term FYM amendment in sub-tropical soil along with mineral N application can improve the LSOMp of the soil. Thus, it can be recommended that the application of FYM at 15 Mg ha⁻¹ in summer and winter with +120 kg ha⁻¹ mineral N can improve SOC and its labile pools in subtropical arid soils. Future studies on LSOMp can be carried out by considering different cropping systems of subtropical climate. Full article

(This article belongs to the Special Issue Effects of Tillage, Cover Crop and Crop Rotation on Soil)

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25 pages, 9245 KiB

Open AccessEditor’s ChoiceArticle

Growth, Yield, Quality, and Phytochemical Behavior of Three Cultivars of Quinoa in Response to Moringa and Azolla Extracts under Organic Farming Conditions

by Rasha S. El-Serafy, Abdel-Nasser A. El-Sheshtawy, Usama A. Abd El-Razek, Ahmed F. Abd El-Hakim, Mostafa M. A. Hasham, Rokayya Sami, Ebtihal Khojah and Amina A. M. Al-Mushhin

Agronomy 2021, 11(11), 2186; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112186 - 29 Oct 2021

Cited by 15 | Viewed by 2559

Abstract

Increased demand for quinoa as a functional food has resulted in more quinoa-growing areas and initiatives to increase grain production, particularly in organic agriculture. Quinoa seeds are a superfood with incredible nutritional benefits. They are abundant in secondary metabolites with significant medicinal activity. [...] Read more.

Increased demand for quinoa as a functional food has resulted in more quinoa-growing areas and initiatives to increase grain production, particularly in organic agriculture. Quinoa seeds are a superfood with incredible nutritional benefits. They are abundant in secondary metabolites with significant medicinal activity. This report was consequently performed to investigate whether Azolla fliculoides (AE) or moringa leaf extract (MLE) foliar spray can be supplemented as organic extracts to enhance quinoa growth and productivity under organic farming. Three quinoa cultivars, KVL–SRA2 (C1), Chipaya (C2), and Q–37 (C3), were grown organically and subjected to foliar spraying with AE or MLE at a 20% ratio, as well as their combination (AE+MLE). Plant performance of the three cultivars was significantly enhanced by MLE or AE applications as compared with control plants. The highest outputs were obtained by AE+MLE treatment, which significantly increased the seed yield by about 29% as compared with untreated plants. Seed quality exhibited a marked increase in response to AE+MLE that was superior in this regard as it showed higher protein, carbohydrates, saponine, tannins, phenolics, and flavonoids content. The C3-cultivar demonstrated the highest productivity, saponine, and flavonoids levels as compared to the other cultivars. Overall, the current study indicated that foliar spray with AE+MLE could enhance growth and productivity as well as quality and pharmaceutical active ingredients of quinoa cultivars grown under farming conditions. Full article

(This article belongs to the Special Issue Application of Biostimulants and Bioeffectors on Crop Production)

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14 pages, 16063 KiB

Open AccessEditor’s ChoiceArticle

Determination of Genetic Distance, Genome Size and Chromosome Numbers to Support Breeding in Ornamental Lavandula Species

by Ewout Van Oost, Leen Leus, Bert De Rybel and Katrijn Van Laere

Agronomy 2021, 11(11), 2173; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112173 - 28 Oct 2021

Cited by 10 | Viewed by 2470

Abstract

Knowledge of phylogenetic relatedness and cytogenetic characteristics can facilitate breeding programs and interspecific hybridization in ornamentals. In this study genetic relationships, genome sizes and chromosome numbers were determined in a collection of 82 lavender genotypes, including 15 hybrids. Amplified Fragment Length Polymorphism (AFLP) [...] Read more.

Knowledge of phylogenetic relatedness and cytogenetic characteristics can facilitate breeding programs and interspecific hybridization in ornamentals. In this study genetic relationships, genome sizes and chromosome numbers were determined in a collection of 82 lavender genotypes, including 15 hybrids. Amplified Fragment Length Polymorphism (AFLP) marker analysis revealed 5 clusters, corresponding to the sections Lavandula, Stoechas, Dentatae, Pterostoechas and Subnudae. Genome sizes varied between 0.76 ± 0.02 pg 2C⁻¹ and 4.80 ± 0.06 pg 2C⁻¹ and chromosome numbers ranged from 2n = 22 to 2n = 100. Genome sizes of hybrids were intermediate to the progenitors genome sizes. All analyzed hybrid genotypes were characterized by even chromosome numbers, with 2n = 48 or 50. Using Principal Coordinate Analysis (PCoA) separate hybrid clusters were identified between the progenitor species clusters. Polyploidy and/or aneuploidy was observed in two hybrids genotypes: L. × intermedia ‘Heavenly Angel’ (2n = 100) and L. × heterophylla ‘Big Boy James’ (2n = 66). Results obtained in this study can be used to predict cross compatibility among different species, thus enabling targeted breeding towards the creation of new improved Lavandula cultivars. Full article

(This article belongs to the Special Issue Cultivated Ornamental Plants: Breeding Aspects)

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19 pages, 1189 KiB

Open AccessEditor’s ChoiceArticle

Nitrogen Release in Soils Amended with Different Organic and Inorganic Fertilizers under Contrasting Moisture Regimes: A Laboratory Incubation Study

by Shihab Uddin, Mohammad Rafiqul Islam, Mohammad Mofizur Rahman Jahangir, Mohammad Mojibur Rahman, Sabry Hassan, Mohamed M. Hassan, Ali A. Abo-Shosha, Atef F. Ahmed and Mohammad Mahmudur Rahman

Agronomy 2021, 11(11), 2163; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112163 - 27 Oct 2021

Cited by 13 | Viewed by 4548

Abstract

Understanding nitrogen (N) release patterns and kinetics is a key challenge for improving N use efficiency in any agroecosystem. An incubation experiment was done to study the N release pattern and kinetics of contrasting soils amended with compost (CO), poultry manure (PM), rice [...] Read more.

Understanding nitrogen (N) release patterns and kinetics is a key challenge for improving N use efficiency in any agroecosystem. An incubation experiment was done to study the N release pattern and kinetics of contrasting soils amended with compost (CO), poultry manure (PM), rice husk biochar (RHB), poultry manure biochar (PMB) and cowdung (CD) combined with chemical fertilizer (integrated plant nutrient system, IPNS approach) under two moisture regimes, viz. field capacity (FC) and continuous standing water (CSW) at 25 °C for 120 days. Our results revealed that NH₄⁺-N was the dominant under CSW conditions, whereas NO₃⁻-N was dominant under FC conditions. Net mineral N data fitted well to the first order kinetic model. Both N release potential (N₀) and rate constant (k) were greater in acidic soil than those of charland soil. The maximum N release varied between 24.90–76.29% of input depending on soil type and moisture status. N mineralization was strongly correlated with urea N application. PM and PMB mineralized in all soil and moisture conditions whereas N immobilization was observed in the case of RHB. N mineralization was strongly correlated with urea N application. Gaseous N losses were different for the organic amendments exhibiting more gaseous N losses in PM, CD and CO based IPNS whereas the lowest gaseous N loss was observed in PMB based IPNS. Biochar based IPNS increased soil pH in all conditions. Thus, the present study suggests that N release depends on soil type, soil moisture and type of organic amendment. However, CO, PM and CD based IPNS can be recommended for both acidic and charland soils in terms of N release as short duration crops will suffer from N deficiency if biochar based IPNS is used in the field. Full article

(This article belongs to the Special Issue Nutrient Recycling: Reduction in the Application of Mineral Fertilizers by Optimization of the Organic Wastes)

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18 pages, 5627 KiB

Open AccessEditor’s ChoiceArticle

Mitigation of Cadmium Induced Oxidative Stress by Using Organic Amendments to Improve the Growth and Yield of Mash Beans [Vigna mungo (L.)]

by Muhammad Umer Chattha, Warda Arif, Imran Khan, Walid Soufan, Muhammad Bilal Chattha, Muhammad Umair Hassan, Najeeb Ullah, Ayman El Sabagh and Sameer H. Qari

Agronomy 2021, 11(11), 2152; https://0-doi-org.brum.beds.ac.uk/10.3390/agronomy11112152 - 27 Oct 2021

Cited by 28 | Viewed by 2731

Abstract

Cadmium (Cd) stress is a serious environmental hazard that has devastating impacts on plant growth and productivity. Moreover, the entrance of Cd into the human food chain by eating Cd-contaminated food also poses serious health issues. Organic amendments (OA) possess an excellent potential [...] Read more.

Cadmium (Cd) stress is a serious environmental hazard that has devastating impacts on plant growth and productivity. Moreover, the entrance of Cd into the human food chain by eating Cd-contaminated food also poses serious health issues. Organic amendments (OA) possess an excellent potential to reduce the adverse impacts of Cd stress. Therefore, the aim of this study was to determine the potential of different OA in improving the mash beans growth and yield grown under Cd-contaminated soil. The soil was spiked with different concentrations of Cd (0, 10 and 20 mg/kg) and subjected to different OA, i.e., control, cow manure (5%), sugarcane press mud (5%) and a combination of cow manure (2.5%) and sugarcane press mud (2.5%). Results indicated that Cd stress induced a significant reduction in growth and yield traits, leaf water status, photosynthetic pigments, protein accumulation and anti-oxidant activities. However, the application of OA appreciably reduced the Cd-induced toxic effects and caused a significant increase in growth and yield. The application of 5% sugarcane press mud remained the top performer and it increased the mash bean growth and yield through improved photosynthetic pigments, leaf water status (56%) and reduced Cd uptake (18%), hydrogen peroxide (H₂O₂) production (38.52%), electrolyte leakage (EL) (42.13%) malondialdehyde (MDA) accumulation (55.88%) and increased accumulation of soluble protein (60.15%) and free amino acids (54%) through improved activities of anti-oxidant enzymes. Therefore, these findings suggested that the application of sugarcane press mud enhanced the growth and yield through reduced Cd accumulation, enhanced photosynthetic pigments, leaf water status, protein and amino accumulation and reduced H₂O₂, EL and MDA accumulation through a stronger anti-oxidant defense system. Full article

(This article belongs to the Special Issue Physio–Devo of Source–Sink Relationship Underlying Abiotic Stress Resilience in Crop Plants)

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