To investigate the key traits influencing the seed setting rate of hulled oats （Avena sativa L.） and their regulatory pathways in the alpine habitat of northwestern Sichuan， this study utilized 27 hulled oat accessions as experimental materials. Measurements were taken for growth period， agronomic traits， photosynthetic characteristics， as well as panicle and grain traits. Multi-trait association analysis was conducted using variance analysis， correlation analysis， multiple linear regression， and path analysis. The results indicated that maturity is a key factor regulating the seed setting rate. The growth period of the tested accessions ranged from 118 to 178 d， with seed setting rates varying between 32.47% and 84.72%. The average seed setting rate of early-maturing accessions （66.93%） was significantly higher than that of late-maturing ones （56.51%， P<0.05）. Mid-maturing accessions showed the highest coefficient of variation， suggesting the existence of specific germplasms with high seed-setting potential. Traits such as panicle number， awn length， and tiller number exhibited considerable variation （CV>30%）， indicating rich genetic diversity. The seed setting rate showed a highly significant negative correlation （P<0.01） with six traits， including plant height and flag leaf length. Path analysis revealed that plant height， effective tiller number， and panicle length are key direct factors regulating the seed setting rate of hulled oats in northwestern Sichuan， primarily through the direct inhibitory effect of plant height and the direct promoting effect of effective tillers. Therefore， for this region， it is advisable to select medium-early maturing varieties with moderate plant height and a high number of effective tillers.

Hulled oat  /  Alpine habitat  /  Maturity type  /  Seed setting rate  /  Trait association  /  Path analysis