Abstract:

To explore the introduction adaptability of Brassica napus in the spring rapeseed region of Xizang and broaden the local rapeseed germplasm resources, this study conducted an introduction trial using Brassica napus varieties from various ecological regions across the country. Using principal component analysis, and membership function analysis, the agronomic traits of multiple varieties were comprehensively evaluated. The results showed that the growth duration of the tested varieties ranged from 130.9 to 141.6 days, exhibiting significant genetic variation with a variation coefficient ranging from 0.15 to 0.32. The yield ranged from 908.8 to 4302.2 kg/hm². The average yield of rapeseed of the Huang-Huai-Hai Region was the highest at 3259.9 kg/hm². Regarding major agronomic traits, the number of silique on the main raceme, the number of silique per plant, branch position, and thousand-grain weight could serve as key indicators for evaluating the adaptability of Brassica napus in Xizang. Principal component and membership function analysis indicated that among the top 10 varieties in terms of comprehensive agronomic traits, two were from the Huang-Huai-Hai Region, one from the upper Yangtze River Region, and seven from the middle Yangtze River Region. Considering the proportion of outstanding varieties among the total tested varieties in each region and the average yield of varieties in each region, the Huang-Huai-Hai and the middle Yangtze River Region performed relatively better. These varieties showed a relatively balanced performance in plant morphology and yield formation, and were superior to the local main-cultivated varieties in Xizang in terms of growth vigor and high-yield potential, possessing good demonstration and promotion potential. The comprehensive analysis demonstrated that the introduction of rapeseed varieties from the Huang-Huai-Hai and the middle Yangtze River Region in Xizang exhibited relatively superior comprehensive agronomic traits. In the future, targeted introduction of varieties from these regions could further enhance the planting efficiency and germplasm improvement level of rapeseed in Xizang.

Key words: rapeseed, introduction, adaptability, agronomic traits, yield, principal component analysis, membership function analysis, comprehensive evaluation, Xizang