This study aimed to evaluate the effect of Lactobacillus plantarum （LP） addition on the silage quality of forage oat （Avena sativa） varieties grown in different regions， thereby providing a theoretical basis for the promotion of new forage oat varieties and the optimization of silage processing techniques. Three oat varieties， ‘Zhongxuyan No.1’ （a new strain）， ‘Qinghai Sweet Oat’， and ‘Qingyin No.2’， were grown in Qinghai and Ningxia. After harvesting at the milk stage， the oats were ensiled under identical conditions with either distilled water （control） or LP treatment for 60 days， after which the silage samples were subjected to sensory evaluation as well as nutritional and fermentation quality analyses. The results showed that LP addition significantly improved the sensory scores and V-Score grades. Nutritional analysis revealed that the crude protein （CP） and ether extract （EE） contents of ‘Zhongxuyan No.1’ silage were significantly higher than those of the other varieties （P<0.01）. Fermentation analysis demonstrated that region significantly affected pH （potential of hydrogen）， lactic acid （LA）， butyric acid （BA）， and the NH₃-N∶TN （ammonia nitrogen∶total nitrogen） ratio in oat silage （P<0.01）， and the pH and BA contents of ‘Zhongxuyan No.1’ were significantly lower than those of the other varieties （P<0.01）. A comprehensive comparison of treatments indicated that LP addition was more beneficial for improving silage fermentation quality. Among the three varieties tested， ‘Zhongxuyan No.1’ performed well in both regions and was identified as the most suitable variety for silage.

Avena sativa  /  Silage  /  Lactobacillus plantarum  /  Quality