Effects of different mixed sowing ratios of oat and forage pea on forage yield and quality in alpine region.

To optimize planting patterns for artificial grassland in the Guinan area, this study systematically compared the forage productivity, nutritional quality, and feeding value of four oat (Avena sativa L.)-forage pea (Pisum sativum L.) mixture ratios (8:2, 7:3, 6:4, and 5:5) with two monoculture controls (oat 'Qinghai 444' and forage pea 'Qingjian No.1'). The 7:3 mixture achieved significantly greater hay yield and crude protein (CP) content than both monocultures and all other mixture ratios (P < 0.05), indicating a synergistic interaction between the cereal and legume components. Feeding value indices-including relative feed value (RFV), relative forage quality (RFQ), total digestible nutrients (TDN), and net energy for lactation (NEL)-were likewise maximized under this ratio. Furthermore, entropy-weighted TOPSIS comprehensive evaluation confirmed that the 7:3 ratio attained the highest integrated score for both yield performance and nutritional quality, significantly outperforming traditional monoculture systems. These results demonstrate that a 7:3 seeding ratio of oat to forage pea represents an optimal strategy for artificial grassland establishment in the Guinan area, simultaneously enhancing forage productivity and nutritional value while providing a practical reference for sustainable mixed forage systems in the region.