Comprehensive character evaluation of 12 wild legume forage germplasms in Tibet

To alleviate the problems of lack of high protein forage during the cold season in alpine grazing area of Nyingchi in Tibet, a comprehensive introduction evaluation of 12 legume forage germplasms was conducted. The grey relationship analysis, membership function analysis, similar priority ratio analysis, principal components analysis were used to evaluate the production performance and nutritional value of these using the weighted analysis method. Using the simple correlation analysis, we analysed 13 main traits: growth duration, plant height, growth rate, fresh dry weight ratio, dry weight ratio, crude protein, crude fat, crude fiber, crude ash, dry matter, nitrogen-free extract, calcium, phosphorus and fresh yield to explore the effects of main traits on fresh yield. The results showed that the different wild legume forages had different adapt ability to Nyingchi environment according to their agronomic characters. The phenological period of Vicia amoena was longest at 174 d, and the yield was highest at 4 665.89 kg·ha⁻¹. The plant height of V. tibetica ‘Qiangna’ was highest (114.75 cm). The average growth rate, fresh dry weight ratio, crude protein, crude ash, calcium of V. angustifolia ‘Dangxiong’ was the highest at 1.60 cm·d⁻¹, 6.89, 20.81%, 13.58%, 1.35%, respectively. The crude fat of V. tibetica ‘Chayu’ was the highest at 8.85%. The nitrogen-free extract, dry matter of V. tibetica ‘Bamadang’ was the highest, being 43.33%, 97.78% respectively, and the crude fibre was the lowest (20.12%). The phosphorus contents of Lablab purpureus ‘Shannan’ was the highest (2.76%). Plant height and growth rate; crude ash and fresh dry weight ratio were of 12 wild legume forages significantly positive correlation. The optimal wild legume forages suitable for utilization in Nyingchi were Vicia angustifolia ‘Dangxiong’ , Vicia amoena and Vicia tibetica ‘Chayu’, based on comprehensive evaluation. The results of this research play an important role in solving the forage shortage and promoting the sustainable development of Nyingchi grassland animal husbandry.