Comprehensive evaluation of the productivity and quality of Avena sativa and Vicia sativa mixed sowing in semiarid and cold regions in Inner Mongolia

This study aimed to explore the best combination, proportion, and harvest time of Avena nuda ‘Mengsiyan 1’, A. sativa ‘Mengsiyan 2’, and A. sativa ‘Qing yin 1’ + Vicia sativa in semiarid and cold regions in Inner Mongolia. The forage yield, nutritional quality, and soil nutrient of A. sativa and Vicia sativa were analyzed and compared based on the average values of their subordinate function at different harvest times. The results were as follows: 1) the plant height, fresh weight, and dry weight of V. sativa increased significantly after sowing treatment; according to the unicast ratio of oat 150 kg·ha⁻¹ and Vicia sativa 75 kg·ha⁻¹, the hay yield of A. nuda ‘Mengsiyan 1’ + V. sativa mixed sowing (3 ꞉ 1) was highest at the milk stage, while the hay yield of A. sativa ‘Mengsiyan 2’ + V. sativa mixed sowing (1 ꞉ 1) was highest at the late milk stage; the hay yield of A. sativa ‘Qing yin 1’ + V. sativa mixed sowing was lower than that of A. sativa unicast at the same harvest time; 2) the crude protein content after the different mixed sowing treatments was higher than A. sativa unicast, and decreased gradually from the heading stage to the late milk stage; the contents of water soluble carbohydrates (WSC) was highest at the late milk stage; the contents of acid detergent fiber (ADF) and neutral detergent fiber (NDF) in different mixed sowing combinations were lowest at a ratio of (1 ꞉ 3); 3) the contents of soil organic matter and available nitrogen were significantly increased among the mixed sowing of A. sativa and V. sativa. The yield and nutritional quality of A. nuda ‘Mengsiyan 1’ + V. sativa (1 ꞉ 3), A. sativa ‘Mengsiyan 2’ + V. sativa (1 ꞉ 1), and A. sativa ‘Qing yin 1’ + V. sativa (1 ꞉ 3) showed a high comprehensive evaluation based on the membership function method in the late milk stage. A. nuda ‘Mengsiyan 1’ + V. sativa (1 ꞉ 3) showed the best multivariate performance score of 0.70.