Genetic diversity analysis of agronomic traits of 41 spring Vicia faba resources to identify optimum materials for cultivation in alpine regions

To identify broad bean materials suitable for planting in cold areas at a high altitude, 19 agronomic characteristics of 41 broad bean germplasm materials were observed and analyzed. The results showed that the 41 broad bean germplasm materials had rich genetic diversity, and the average coefficient of variation and genetic diversity index of the 19 agronomic traits were 30.80% and 1.715, respectively. Of the 19 agronomic traits, grain yield was significantly positively correlated with aboveground biomass, underground biomass, and the number of nodules (P < 0.05), while 100-grain weight was significantly negatively correlated with plant height, stem diameter, stem dry weight, underground biomass, pod number, and aboveground biomass (P < 0.05). Five principal components were obtained by principal component analysis, and the cumulative contribution rate reached 79.521%. The first principal component mainly reflected the grain yield, and the second principal component mainly reflected the grain length and width (size), which in turn reflected the phenotypic characteristics of the 41 broad bean germplasm resources to a greater extent. The 41 broad bean material samples were divided into two groups using a systematic clustering method: groups I and Ⅱ contained 36 and 5 samples, respectively. A membership function analysis showed that broad bean materials 21, 25, 29, and 37 provided the best comprehensive performance in group II, and they were thus identified as being excellent materials for cultivating forage and forage seeds of high quality and high yield in alpine regions.