In the central Great Plains, winter wheat is used for over-winter grazing for cattle and sheep until the late spring months, when livestock are moved to grass pasture. As the popularity of summer cover crops increases, interest in their use in forage production systems increases as well. There is specific interest in the opportunity to increase productivity by the inclusion of a crop grown in the fallow season of winter wheat fields. The intensification of systems in a resource (water and/or nitrogen) limited region could decrease winter wheat forage production influencing a system’s ability to sustain continuous forage production. Nitrogen (N) management could be effective in mitigating negative impacts on winter wheat. The objective of this study is to evaluate the influence of different summer forage crop species and different N management strategies in a multi-year continuous winter wheat forage production system in the central Grain Plains. Increased production of dry matter and crude protein was observed by implementing summer forage crops into a winter wheat forage system. A deleterious effect of summer crops compared to traditional fallow periods was observed but mitigated by the split application of N even compared to the same rate applied at pre-plant. Full article

Applying nitrogen (N) fertilizer at irrational rates and basal topdressing ratios typically leads to high resource wastage and serious environmental pollution and is a global problem. A pot experiment was conducted between 2020 and 2021 to investigate the effects of different N application rates and basal topdressing ratios on the growth, yield, quality, and water- and N- use efficiencies of forage maize. Four N treatments were used, with the following levels: 0 kg/ha (N₀), 70 kg/ha (N₇₀), 140 kg/ha (N₁₄₀), and 210 kg/ha (N₂₁₀); and two basal topdressing ratios of N fertilizer were tested, namely: 2:8 and 4:6. An increased N application rate, from 0 to 200 kg/ha, increased whole fresh and dry yields. N fertilization increased the crude protein (CP) content of different plant parts (stems, leaves, and ears), as well as at the whole plant level, but decreased neutral and acid detergent fiber content. The dry matter water use efficiency (WUE_DM) increased, while the partial-factor productivity of applied N decreased with an increasing N application rate. Compared with N₀, the 2-year average dry matter yield under N₇₀, N₁₄₀, and N₂₁₀ increased by 21.8%, 27.6%, and 38.2%, respectively, while WUE_DM increased by 19.1%, 28.7%, and 45.0%, respectively. At the 2:8 basal topdressing ratio, the dry matter yield, CP content, and N recovery efficiency under all N application rates were higher at harvest compared to the 4:6 ratio during normal rainfall years, while dry matter yield and WUE_DM were both lower compared to the 4:6 ratio during dry years. In conclusion, during a normal rainfall year, a N application rate of 210 kg/ha, with a basal topdressing ratio of 2:8 between the sowing and jointing stages, is considered the optimal N fertilizer application strategy to improve forage maize production in the semi-arid areas of the Chinese Loess Plateau. Full article

Mixing cereal with legume crops is an efficient approach for improving forage production and ensuring the sustainable development of agriculture and livestock. However, the knowledge of the relationship between forage production and interspecific competition in the forage oat (Avena sativa L.) and common vetch (Vicia sativa L.) mixed cropping system remains unclear. A 2-year field experiment was conducted in 2020 and 2021 to investigate the effects of different mixed cropping systems (peer mixing (PM), alternate-row mixing (AM), cross mixing (CM), bar mixing (BM), sole forage oat (SO), and sole common vetch (SV)) on the dry matter production, forage quality, land equivalent ratio (LER), and competition parameters. The results showed that the system forage yield increased by 13.4–202.8% when forage oat was mixed with common vetch (p < 0.05). However, no significant difference was obtained between the AM and PM mixed cropping systems. Additionally, the forage oat–common vetch mixed cropping improved crude protein yield by 52.5–150.1% compared with monocultures (p < 0.05). The LER values were greater than the one when forage oat was mixed with common vetch, especially for the AM system (averaged 1.38). In addition, forage oat was the dominant crop and had higher aggressiveness and competitive ratios compared to common vetch, but without a significant difference in the aggressiveness and competitive ratio in mixed cropping systems. It indicated that mixing of cereal with legume crops was helpful in enhancing resource use efficiency without obvious interspecific competition. Consequently, the AM mixed cropping system is recommended for supporting the sustainable development of agriculture and livestock production in the arid region of China when considering both forage production and nutritional quality. Full article

Investigating the responses of forage crop yield, quality, and nitrogen (N) use efficiency to different N application rates is beneficial for guiding proper N fertilization regimes and for reducing reactive N environmental pollution. A field experiment was conducted to investigate the effects of different N application rates on above-ground dry matter yield, forage quality, crop N uptake, N use efficiency (NUE), and ecosystem economic benefits (EEBs) of forage sorghum cultivated on the Longdong Loess Plateau in 2019 and 2020. Five N application rates were tested, namely 0, 80, 160, 240, and 320 kg·ha⁻¹ (referred to as N₀, N₈₀, N₁₆₀, N₂₄₀, and N₃₂₀, respectively). The maximum above-ground dry matter yield (22.3 t·ha⁻¹ in 2019 and 18.0 t·ha⁻¹ in 2020) was obtained at an N application of 160 kg·ha⁻¹. Forage sorghum crude protein (CP) content increased significantly with increasing N application rates (the CP content at N₃₂₀ was 7.4% and 8.6% in 2019 and 2020, respectively). In contrast, neutral detergent fiber (NDF) and acid detergent fiber (ADF) were only affected by high N application rates (NDF and ADF were significantly higher in N₃₂₀ compared with N₀ and N₉₀). The relative feed value (RFV) was significantly higher in N₀ compared with N₃₂₀. Crop N uptake was significantly higher in N₁₆₀ compared with N₀ (25.7% increase to 249.4 kg·ha⁻¹ in 2019 and 40.5% increase to 247.4 kg·ha⁻¹ in 2020, respectively). NUE decreased linearly as N rates increased, but NO₃⁻–N residue (0–200 cm), reactive N loss (Nr loss), and greenhouse gas (GHG) emissions increased. Private profitability and EEB were the largest at N₁₆₀ (private profitability at N₁₆₀ was 514.2 USD·ha⁻¹, and EEB at N₁₆₀ was 392.7 USD·ha⁻¹). Above-ground yield and optimum forage quality must be maximized, while simultaneously safeguarding farmer income and reducing environmental pollution from N fertilizers. Therefore, the optimum N application rate for forage sorghum cultivation in the dry areas of the Loess Plateau is recommended at 160 kg·ha⁻¹. Full article

Dual-purpose cover crops can cycle nutrients on dairy farms while providing additional quality forage. However, questions remain regarding the crop species best suited to this function. A two-year field experiment with five small-grain winter cover crops, including rye (Secale cereale), wheat (Triticum aestivum), and three triticale varieties (×Triticosecale varieties), was conducted on an active dairy farm. The rye produced the highest yield at 4612 kg ha⁻¹, followed by the forage varieties of triticale, which averaged 4004 kg ha⁻¹, whereas the wheat and one nonforage triticale produced only 2950 and 2987 kg ha⁻¹, respectively. The wheat had the highest crude protein (CP) at 11%, and a relative feed value (RFV) of 132, and it had the greatest milk-production potential, which was 1729 kg milk/Mg of forage. Yet, the rye (CP: 10.4%; RFV: 112) had the greatest milk-production and economic potentials per hectare due to the high forage yield, valued at USD 714 ha⁻¹, whereas the nonforage triticale had the least economic value (USD 326 ha⁻¹), despite its high forage quality (CP: 9.5%; RFV: 120). The forage triticale varieties were intermediate performers compared with the rye and wheat on a yield and quality basis. Mirroring the yield, the rye also removed the most nitrogen (77.3 kg ha⁻¹) and phosphorus (20.8 kg ha⁻¹). The species differences were found to be contingent on the manure application. The results of this experiment suggested that winter rye is the most efficient cover crop for harvesting and nutrient-recycling purposes. Full article

Legume–grass mixture can greatly improve soil fertility to support the sustainable productivity. Root litter is an important source of soil organic matter, but its link with soil nutritional status in forage mixtures is not clear. This study was aimed to uncover whether the relationship of carbon (C) and nutrients between root and soil would change with mixing ratio. Changes in organic C, nitrogen (N), and phosphorus (P) of root and soil were studied in a 2-year experiment with sole common vetch (Vicia sativa), sole oat (Avena sativa), and their mixtures of different mixing ratios under N, P, and N + P fertilization. Root C, N, and P concentrations decreased with decreasing proportion of common vetch in the grasslands. Nitrogen fertilization significantly improved root N concentration (by 4.5–10.1%), while P fertilization decreased root N concentration (by 10.1–18.4%). The effect of mixing ratio on soil C and nutrients was stimulated by fertilization, although soil C, N, and P contents barely changed with mixing ratio. Mixing and fertilization significantly affected C, N, and P stoichiometric ratios of root and soil (besides soil C:N). Soil C, N, and P contents were strongly positively correlated with root C concentration. The results indicated that increasing legume proportion in the mixture may improve root C and nutrients, which can be stimulated by fertilization. Root quality is closely correlated to soil nutritional status in the mixture. This study further reveals the mechanism how the root is potentially involved in affecting soil fertility and provides a scientific basis on the extensive use of common vetch-oat mixture in the Loess Plateau of China. Full article

Due to depleting water supplies and the cultivation of high water-demanding crops such as lucerne, the effect of water deficits in crop production has become a major concern, especially in semiarid regions of China. A six-year field experiment (2012–2018) was conducted to evaluate soil water recovery and soil fertility after lucerne-to-crop conversions on the western Loess Plateau of China. Six rotation treatments (lucerne initially grew from 2003 to 2012 followed by the rotation of other crops or fallow until assessments in 2018) were: (1) lucerne (Medicago sativa L.)–lucerne (L-L); (2) lucerne–fallow (L-F); (3) lucerne–wheat (Triticum aestivum L.) (L-W); (4) lucerne–corn (Zea mays L.) (L-C); (6) lucerne–potato (Solanum tuberosum L.) (L-P); and (6) lucerne–millet (Setaria italica) (L-M). The same crops were grown each year after cultivation during 2013–2018. According to the findings, all rotation types gradually increased the soil water content, with the 0–110 cm soil layer experiencing the maximum soil water replenishment rate, followed by the 110–200 and 200–300 cm soil layers. After converting lucerne to crops, the amount of organic carbon, total nitrogen, and mineral nitrogen in the soil decreased, whereas total phosphorus and accessible phosphorus increased. Soil bulk density was reduced under rotation treatments. Soil water absolute restoration index was the highest under L-F, followed by L-C, L-W, L-P, and L-M. The rate of soil water recovery was 39.5, 33.0, 33.7, 33.5, 29, and 8.2 mm yr⁻¹ under L-F, L-W, L-C, L-P, L-M, and L-L, respectively. The net economic return was greatest under L-C, followed by L-L, L-W, L-P, and L-M. From the analysis of the long-term experimental results, this study shows that the effect of soil water restoration is greatest when continuous alfalfa is converted into wheat, corn, and potato or fallow after 9 years. When the economic benefits and soil moisture recovery are considered comprehensively, corn sown in a ridge–furrow system with fully plastic film annual mulching is the most suitable field management practice after lucerne-to-crop conversion on the western Loess Plateau of China. Full article

Mixtures of legume and grass are used worldwide to gain advantages in forage production and ecological maintenance. However, competition for nutrients by legumes in mixtures has not been fully explored. The aim was to determine how the forage proportion affected nutrient competition in legume and grass mixtures. Treatments included two species combinations and five sowing ratios. Competitive ratios (CR) of lucerne for nitrogen (N) and phosphorus (P) over two grasses were assessed to analyze how the lucerne proportion in mixtures affected the competition. Total N and P uptake were mostly lower under timothy-containing mixtures (MPs) than under smooth bromegrass-containing mixtures (MBs). Proportions of both N (N_M%) and P uptake (P_M%) of lucerne were higher under MPs than under MBs. Higher total N and P uptake were found under half-lucerne mixtures (M5P5 or M5B5) than under other grasslands. The N_M% and P_M% tended to be higher under half-lucerne mixtures, although they showed little difference among mixtures. Lucerne CR was greater under MPs than under MBs, and was greater than grass CR when lucerne was in lower proportion in the mixtures. There was little difference in soil N density among grasslands of the same cut, whereas soil P density was variable. Competitiveness of lucerne depends largely on the initial sowing ratio. High ratios of lucerne significantly reduce soil P density, leading to P limitation and reduced N and P uptake. On the Loess Plateau of China, mixing lucerne with smooth bromegrass is recommended to increase the uptake and harvest of N and P, specifically at the sowing ratio of 5:5. Full article

Most of the arid and semi-arid regions, particularly in the Mediterranean area, suffer from the lack of a sufficient quantity of high-quality feed, as well as a low amount of rainfall that is unevenly distributed, resulting in the region being highly vulnerable to drought. A field experiment was carried out at the experimental station of the Faculty of Desert and Environmental Agriculture, Fuka, Matrouh University, Egypt during the winter seasons of 2018/19 and 2019/20 to study the performance of triticale (X Triticosecale Wittmack), grown under water deficit conditions, in terms of productivity and quality. The study investigated the influence of five levels of potassium fertilization (PF; 0, 43.2, 86.4, 129.6, and 172.8 kg ha⁻¹) and ascorbic acid (AA; 0, 25, 50, 75, and 100 mg L⁻¹) that was applied to the triticale grains before sowing and humic acid (HA; 0, 2.4, 4.8, 7.2, and 9.6 kg ha⁻¹) that was applied as powder to the soil 21 days after sowing followed by sprinkler irrigation on triticale forage and grain production when forage was removed at variable ages at cutting (AC), determined as days after sowing (AC; 40, 65, 90, 115, and 140 DAS) on forage yield and nutritive value, in addition to the final grain yield of triticale. The experimental design was a central composite design with one replicate. Results indicated that the PF*AC interaction was significant, and it gave values of 84.78 and 238.00 g kg⁻¹ for crude protein (CP) and degraded neutral detergent fiber (DNDF). In addition, the interaction between AA and AC was significant for CP, acid detergent fiber (ADF), 100-grain weight (100 GW), number of spikes m⁻² (NSM⁻²), and plant height (PH). Moreover, the AC*HA interaction was significant with values of 175.17 and 247.00 g kg⁻¹ for CP and DNDF, respectively, and 0.55 t ha⁻¹ for grain yield (GY). Age at cutting exerted the strongest effect on the studied characteristics. It was observed that the contents of neutral detergent fiber (NDF), ADF, acid detergent lignin (ADL), and non-fiber carbohydrates (NFC) in the triticale forage significantly increased when the crop was cut at an advanced age, unlike CP, DNDF, GY, NSM⁻², 100 GW, and PH that decreased with advanced AC. The highest values of 271.00, 256.00, and 268.00 g kg⁻¹ for DNDF were obtained with higher levels of either PF, AA, or HA, respectively. However, the highest value of GY (0.97 t ha⁻¹) was obtained with higher levels of PF*HA averaged over the two seasons. The interaction between AA*HA resulted in 393.39, 311.00, 27.13 g kg⁻¹, and 0.94 t ha⁻¹, for NDF, DNDF, ADL, and GY, respectively. The highest significant NDF (413.11 g kg⁻¹) and DNDF (307.50 g ka⁻¹) values were obtained with the application of high levels of either AA or HA. In the dual-purpose production system, it is recommended to cut the triticale crop at 65 DAS to achieve the optimum balance between forage yield and quality on the one hand, and final grain yield on the other hand. In the arid regions, application of PF, AA, and HA could help in reducing the damage caused by water deficit. Full article

Integrating a forage crop into the fallow (F) of the peanut (Arachis hypogaea L.) (P) mono-cropping system is a practical approach to provide forage yield and increase the resource use efficiency. However, little information about the comprehensive assessment of water utilization and economic benefits in the crop–livestock system exists for the North China Plain (NCP). This study aims to identify the crop rotation for optimizing water management and enhance economic benefit. The field experiment was performed over three years (2011–2014) to assess production, water utilization, and economic benefits when inserting forage triticale (X Triticosecale Wittmack) (T) into the peanut mono-cropping system. Results showed that replacing the fallow F-P cropping system with forage triticale provided a substantial amount of forage (the average of 9.8 t ha⁻¹ per year) and enhanced the average system productivity by 85.1%. Cultivation of forage triticale during the fallow period decreased the subsequent peanut pod yield by 8.3% due to a 19.3% decline in soil water storage capacity during the sowing stage of peanut. Replacing fallow with forage triticale increased the system net income by 1016.2 US$ ha⁻¹ and the water use efficiency (WUE) by 30.0%, while not affecting the economic efficiency of water use (EEWU), and thus can be recommended as a better option for maintaining relatively high system production, economic benefit, and WUE in NCP. Full article

Interspecific interactions and recovery growth play an important role in crop growth, development and ultimately yield in intercropping systems. However, the impact of different water and nitrogen levels on intercropping production, interspecific interactions between intercrops, and the recovery growth of late-maturing crops is still unclear. A two-year field experiment was conducted in Yangling, Shaanxi province, to investigate the dynamics of interspecific interactions, and the effects of interspecific interactions on crop growth and yield. The experiment consisted of three factors, including three cropping systems (wheat/maize intercropping, sole wheat, sole maize), three nitrogen (N) levels and two water applications (supplementary irrigation and rainfed). The results demonstrated that, during the co-growth period, intercropped wheat was more competitive than intercropped maize; so, intercropped wheat showed a yield advantage. Intercropping increased maize yield under irrigated conditions, and this was attributed to the full recovery growth of intercropped maize after wheat harvest. However, rainfed and nil nitrogen aggravated the interspecific competition, and water deficit under maize rows, in turn, limited the recovery growth of intercropped maize, leading to yield reduction. However, compared with sole maize, the yield of intercropped maize decreased, indicating nitrogen deficiency limited the recovery growth of intercropped maize. Among all treatments, the intercropping of medium nitrogen fertilizer with irrigation had the best yield improvement and land use advantages, the total yield of intercropping was 14.8% higher than that of sole cropping, and the land use efficiency increased 16%. These results confirmed that supplementary irrigation and optimal nitrogen application alleviated the interspecific competition, promoted the recovery growth of intercropped maize and improved the yield of wheat/maize intercropping system. Full article