Evaluation of germplasm resources used for fertilizing and feeding in Vicia sativa based on grey correlation analysis

Vicia sativa is an useful green fertilizer crop which has the advantages of high biomass, high palatability, high nutritional value, and strong reproducibility. During the growth period, V. sativa can be cut multiple times and it has considerable economic value. In this study, yield and quality of 25 varieties of V. sativa were examined through correlation analysis. This detailed evaluation was conducted on the main traits, nutritional quality, and nitrogen fixing capacity of different varieties of V. sativa using grey correlation analysis. The research purpose was to screen for the most suitable V. sativa varieties for green fertilizer planting in Qinghai. In this study, there were significant differences in agronomic traits and quality traits of the 25 varieties of V. sativa, which indicated high breeding potential. Correlation analysis showed that growth period was significantly positively correlated with plant height, stem diameter, fresh grass yield, above-ground dry weight, underground dry weight, nitrogen carrying capacity, crude protein yield, neutral detergent fiber, and acid detergent fiber. However, it was significantly negatively correlated with relative feeding value. The fresh grass yield was positively correlated with growth period, stem diameter, hay yield, nitrogen transport, and crude protein yield. Above-ground dry weight and underground dry weight were positively correlated with nitrogen transport and crude protein yield. In field trials, the emphasis should be placed on selection of varieties with moderate growth period, higher plant height, larger stem diameter, and higher yields of fresh grass and hay. The results from grey correlation analysis showed that ‘Ximu 333’ ‘Qingshui River common vetch (linen)’ ‘Shizong common vetch’ ‘Sujian 5 common vetch’, and ‘7401 common vetch’ had more suitable nutritive traits and nitrogen fixing ability. These varieties had a high level of production performance in Qinghai Province. Therefore, they were found to be suitable for widespread cultivation.