Evaluation of Nutritive Values through Comparison of Forage Yield and Silage Quality of Mono-Cropped and Intercropped Maize-Soybean Harvested at Two Maturity Stages

Abstract

Maize and soybean intercropping is a cereal-legume intercropping pattern that not only increases grain yield but also improves the nutritional value of silage. Experiments were conducted in the summer season to compare the yield and nutritional composition of the forage and silage quality of mono-cropped maize and intercropped maize-soybean harvested at two stages of maturity. The main treatments were one sole crop maize (SM) and four maize-soybean intercropping patterns (one-row maize to one-row soybean (1M1S), one-row maize to two-row soybean (1M2S), one-row maize to three-row soybean (1M3S), and two-row maize to one-row soybean (2M1S). The crops were harvested when the maize reached the milk (R3) and maturity (R6) stages. Results indicated a significant increase in the fresh biomass and dry-matter production of maize fodder alone compared with those of maize intercropped with soybean fodder. After 60 days of ensiling period, silage samples were analyzed for pH, organic acids, dry matter, crude protein (CP), ether extract, neutral detergent fiber (NDF), acid detergent fiber (ADF), and other mineral compositions. All intercropped silages showed higher CP values (1M1S, 12.1%; 1M2S, 12.2%; 1M3S, 12.4%; and 2M1S, 12.1%) than the SM silage (8.7%). Higher organic acids were produced in 1M3S than in the other silages. Correlation data showed that CP was highly correlated with lactic acid but negatively associated with crude fiber, nitrogen-free extract, and NDF. Thus, the intercropping of maize and soybean silage is recommended due its enhanced crop production, nutritional values in dairy animals, and prolific animal feedings and because it was scientifically evaluated as a feed stuff. This study indicated that 1M3S was the most preferable among intercropped silages in terms of nutrient composition.