Effects of Maize Varieties on Biomass Yield and Silage Quality of Maize–Soybean Intercropping in the Qinghai–Tibet Plateau

Forage deficiency is the bottleneck that restricts development of plateau animal husbandry. Maize (Zea mays L.)–soybean (Glycine max L.) intercropping can improve forage biomass yield and silage quality. This experiment was conducted in Ganzi Tibetan Autonomous Prefecture to explore effects four maize varieties (M1, Rongyu Silage No. 1; M2, Yayu 04889; M3, Demeiya M4, Zhenghong 505) on yield, nutritional composition, quality maize–soybean intercropping. The results showed M1S had highest total dry matter (18.03 t ha−1), M3S crude protein (CP) content (8.46% DM), soybeans water-soluble carbohydrate (WSC) (8.55% DM). After silage, CP (13.44% DM) mixed higher, contents neutral detergent fiber (39.42% acid (25.42% were lower than those alone. WSC (4.45% higher pH value (4.46) ammonia–nitrogen nitrogen (3.97%) soybean membership function analysis best fresh feeding utilization, followed by M1S. Therefore, (Demeiya No 1. intercropped with soybeans) recommended high-altitude areas.