关键词: 无芒雀麦, 干草产量, 生产性能, 结构方程, 草层结构

Abstract: In order to select and breed high and stable yields of Bromus inermis Leyss. germplasm resources suitable for cultivation on the Qinghai-Tibet Plateau,to alleviate the problem of outstanding contradiction between supply and demand of grass and livestock in the Plateau,and to promote ecological environment management in the alpine region,in this study,13 domestic and foreign Bromus inermis Leyss. germplasm resources were evaluated on their main agronomic traits for production performance for two years using affiliation function analysis on the premise of high forage yield;and then the selected superior resources were analysed on grass layer structure,material distribution and nutritional quality to explore their superior commonalities. The results showed that among the 13 Bromus inermis-Leyss. germplasm resources,B01,B09,B12 and B13 had the best performance in terms of hay yield and overall traits,and could be used as excellent herbage materials for cultivating high yielding and stable forage germplasm resources;among these,B01 and B09 are shorter grasses suitable for replanting in natural grassland;B12 has good nutritional quality and could be used to improve the palatability of Bromus inermis-Leyss;B13 has the highest cumulative yield of two years and the highest percentage of leaves,making it suitable to be used as excellent grass in pursuit of grass production. In future cultivation and breeding,the focus should be paid on Bromus inermis-Leyss. plant height,tillering capacity and root characteristics of the germplasm to improving its hay yield. This study provided a theoretical reference for the parental selection about high and stable yields Bromus inermis-Leyss germplasm resources in Qinghai-Tibet Plateau region.

Key words: Bromus inermis-Leyss., Hay yield, Production performance, Structural equations, Grass layer structure