关键词: 半干旱区, 饲用燕麦种质, 表型性状, 遗传多样性, 综合评价

Abstract:

Evaluation of genetic diversity could benefit the identification of optimal parental combinations for obtaining segregating offspring with maximum genetic variability, and facilitate the introgression of favorable genes from various germplasm into commercial cultivars. In this study, Avena sativa L. collections including 45 Chinese and international accessions were analyzed through phenotypic analysis of 20 agronomic traits, and provided the basis for promoting the breeding of forage oat varieties. Main conclusions were as follows:there were significant differences in the phenotypic traits diversity of the tested materials, all of the phenotypic traits showed abundant variation, and the genetic basis was broad. The genetic diversity of the grain weight of main spike was the highest (3.86), and the co-efficient of variation of grain number per plant was up to 36.98%. There were different degrees of correlation among the phenotypic traits of the tested materials. The principal component analysis transformed 10 traits into four principal components that represented 83.735% of the original index, and constructed a quantitative evaluation function model with four principal component factors as parameters. The results of two-dimensional analysis showed that Z4 (Qingyin 1), Z5 (Bauntebue), Z6 (Dingyan 2), Z7 (Dingyin 1), Z12 (Jerry), Z21 (Marion), Z22 (Trophy) and Z32 (Loevile) were the best materials of factor coordination, and the comprehensive performance was excellent. According to the geographical origin and phenotypic traits of Avena sativa L. germplasm, they were clustered into three groups:group Ⅰ and Ⅲ could be used as a good parents for breeding high yield, disease resistance and antifreeze varieties, and group Ⅱ including the abundant geographical origin could be used as breeding target character of the excellent parents.

Key words: Semi-arid area, Avena sativa L.germplasm, Phenotypic traits, Genetic diversity, Comprehensive evaluation