Optimization of Alfalfa-Based Mixed Cropping with Winter Wheat and Ryegrass in Terms of Forage Yield and Quality Traits

The Effect of Inorganic Nitrogen Fertilizers on the Quality of Forage Composed of Various Species of Legumes in the Northern Part of a Temperate Climate Zone

This study focuses on the effect of inorganic nitrogen fertilizers on the quality of perennial grasses. Both grasses and legumes are important in swards, and each type of grass has different biological and ecological properties. Legumes in multi-species swards, especially in their early ages, benefit other Poaceae grasses by improving their growth. When evaluating individual cuts over a three-year period, it was determined that the quality indicators of the forage were significantly influenced by the year of use, N fertilizer application, and the different species compositions of the swards. In many cases, N fertilizers significantly reduced the CP content while tending to increase MADF and NDF. Monoculture grass swards had the highest WSC content; in most cases, N fertilizers increased the WSC content in the forage. DMD was the lowest in the first year of use, specifically in the first cut. Our three-year experiment, which investigated twelve swards with different species compositions, demonstrated that legume grasses improved the quality indicators of forage and contributed to maintaining a more stable overall forage yield over the years. As the climate continues to become warmer, there is a growing need to study a wide range of plant species and different varieties suitable for local growth conditions.

Application of Bio-Fertilizers Improves Forage Quantity and Quality of Sorghum (Sorghum bicolor L.) Intercropped with Soybean (Glycine max L.)

In recent years, application of bio-fertilizers (BFs) in intercropping systems has become known as one of the main sustainable and eco-friendly strategies for improving the quantity and quality of forage crops. In order to evaluate the forage quantity and quality of sorghum intercropped with soybean, a two-year field experiment was carried out as factorial based on a randomized complete blocks design (RCBD) with three replications. The first factor was different cropping patterns including soybean monocultures with densities of 40 and 50 plants m-2 (G40 and G50), sorghum monocultures with densities of 10 and 15 plants m-2 (S10 and S15) and intercropping of two plants with the mentioned densities. The second factor was non-application (control) and application of bio-fertilizers. The results demonstrated that the highest dry forage yield of sorghum (21.22 t ha-1) was obtained in monoculture conditions with density of 15 plants m-2 and inoculation with bio-fertilizer (S15+BF). The maximum crude protein (CP = 149.6 g kg-1 DM), ash (113.2 g kg-1 DM), water soluble carbohydrates (WSC = 251.16 g kg-1 DM), dry matter intake (DMI = 26.83 g kg-1 of body weight), digestible dry matter (DDM = 668.01 g kg-1 DM), total digestible nutrients (TDN = 680.42 g kg-1 DM), relative feed value (RFV = 142.98%) and net energy for lactation (NEL = 1.625 Mcal kg-1) were observed in the intercropping of S10G50 inoculated with BF. Interestingly, application of bio-fertilizers enhanced the content of CP, ash, WSC, DMI, DDM, TDN, RFV and NEL by 7.5, 8, 11.7, 3.6, 2.3, 12.3, 5.9 and 3.5% when compared with the control (non-application of bio-fertilizers). In all intercropping patterns, the total land equivalent ratio (LER) value was greater than one, representing the advantage of these cropping patterns in comparison with sorghum monoculture. The highest total LER was recorded in the intercropping of S15G40 and S10G50 following application of BF. Additionally, the highest monetary advantage index (MAI) was calculated in the intercropping of S15G40+BF. Generally, it can be concluded that the intercropping of S10G50 along with bio-fertilizer inoculation could be suggested as an eco-friendly strategy for improving the forage quantity and quality under low-input conditions.

Influence of Different Harvesting Stages and Cereals-Legume Mixture on Forage Biomass Yield, Nutritional Compositions, and Quality under Loess Plateau Region

One of the main problems in the animal industries currently is the constant provision of forage in sufficient amounts with acceptable nutritional content for large and small ruminants, as livestock is a significant source of income for rural people in the Loess Plateau region. Cereals and legumes are essential forage crops because of their nutritional significance, particularly the protein concentration in legumes and the fiber content in cereals. Therefore, combining cereal and legume crops may be a practical solution to the problems of inadequate forage nutrition, an insufficient amount of forage, unsustainable agricultural methods, and declining soil fertility. The current study predicts that mixed cropping of cereals and legumes at the harvesting stage of the soft dough stage and maturity stage based on the cereal growth stage will have different effects on forage biomass output, forage quality index, and nutritional value of the forage. In this study, wheat (Triticum aestivum) and ryegrass (Lolium multiflorum) are used as cereal crops and pea (Pisum sativum), and alfalfa (Medicago sativa) are used as legume crops. Three sample replicates and a split-plot design with a randomized block design are used. The study is conducted in the 2020−2021 and 2021−2022 cropping seasons. The experimental results show that cereal−legume mixed cropping, particularly the cereal−alfalfa combination, has a positive impact on the biomass yield and nutritional composition of the forage. However, adding peas to cereal has a negative impact on biomass yield, nutritional composition, mineral composition, and forage quality index. Among the treatments, ryegrass−alfalfa mixed cropping was shown to have higher values of WSC%, CP%, EE%, CF%, and ash% in both growing seasons. The values are WSC (15.82%), CP (10.78%), EE (2.30%), CF (32.06%), and ash (10.68%) for the 2020−2021 cropping seasons and WSC (15.03%), CP (11.68%), EE (3.30%), CF (32.92%), and ash (11.07%) for the 2021−2022 cropping seasons, respectively. On the other hand, the current study finds that cereal−alfalfa mixed cropping had a detrimental impact on NDF and ADF concentrations. All nutritional indices, including CP, WSC, EE, CF, ash, NDF, and ADF, have favorable correlations with one another. Furthermore, in both growing seasons, RA, ryegrass−alfalfa mixed cropping, has higher mineral compositions and forage quality indicators. Furthermore, harvesting times have a significant impact on the fresh biomass yield, dry matter yield, nutritional compositions, mineral compositions, and forage quality parameters (p < 0.001), with the highest values being shown when harvesting at the soft dough stage. The current study concludes that, based on chemical composition and quality analysis, the soft dough stage is the greatest harvesting period, and that the cereal−alfalfa mixed cropping is the most preferable due to its maximized quality forage production and nutritional content in livestock feedstuff in the Loess Plateau region.