Comprehensive evaluation and of agronomic traits of 50 Bromus inermis germplasm accessions

To screen superior Bromus inermis germplasms suitable for cultivation in the Urumqi region of Xinjiang, 50 Bromus inermis accessions were evaluated based on phenological phases and agronomic traits, including plant height, number of nodes, basal stem length, stem diameter, peduncle length, flag leaf area, forage yield, and seed yield. The agronomic traits were analyzed using correlation analysis, principal component analysis (PCA), and membership function analysis. The results showed that the growth period of the 50 Bromus inermis accessions ranged from 83 to 111 days, with substantial variation in agronomic traits (coefficient of variation: 12.65%–48.25%). Stem diameter and peduncle length exhibited a highly significant positive correlation with hay yield (P < 0.01), while plant height showed a significant positive correlation with hay yield (P < 0.05). The first five principal components identified by PCA accounted for a cumulative contribution rate of 71.257%. Based on membership function analysis, ten accessions outperformed the control cultivar 'Wusu No. 1.':A₁, A₃₀, B₈, B₅, A₁₆, B₂, A₁₃, A₃₁, A₂₉, and B₁₈. This study provides potential germplasm resources for breeding high-quality new varieties of Bromus inermis.