Abstract:

This research aimed to identify high-quality oat （Avena sativa） varieties suitable for the alpine climate in Shigatse. Eighteen forage oat varieties were selected and cultivated in Shigatse City， and their agronomic traits， yield， nutritional quality， and silage characteristics were determined. The results indicated that the oat variety Tianyan 75 had the highest hay yield （up to 13.40 t·ha^-1）， followed by Taike （11.39 t·ha^-1）. Taike had the highest crude protein content， at 12.17%. Dingyan No.2 had the lowest neutral detergent fiber （NDF） content， at 46.34%. Gaoyan 17， Dingyan No.2， Youmu No.1， Qianfeng， and Taike had lower acid detergent fiber （ADF） contents than the other tested varieties， with the ADF contents being 24.07%， 24.75%， 25.10%， 26.15%， and 26.36% respectively. After 80 days of natural ensiling， all varieties showed good fermentation except for Indimite， Longyan No.3， Gloria， Gaoyan 16， and Dingyan No.2， whose silage pH values were higher than 4.2. Taike and Tianyan 2+ had comparatively high lactic acid contents. The ammonia nitrogen content of all varieties was lower than 10%； Indimite and Youmu No.1 had the highest butyric acid contents at >1%， while the other varieties were all lower than 1%. Qianfeng， Youmu No.1， and Taike ranked the top three in terms of relative feeding value and forage grading index of their silages， exhibiting high forage value. Based on a multivariate consideration of yield， nutritional quality， and silage characteristics， and according to the results of principal component analysis， grey relational analysis， and entropy-weighted TOPSIS analyses， Qianfeng， Youmu No.1， and Taike are recommended as high performing varieties of forage oats in the alpine regions of Shigatse.

Key words: alpine region, oat, silage quality, comprehensive evaluation, variety screening