甘蓝型油菜种子萌发期耐苯磺隆种质筛选与综合评价

本研究旨在探讨不同基因型甘蓝型油菜种子萌发期耐除草剂苯磺隆特性, 建立其筛选的评价体系, 选育萌发期耐苯磺隆的甘蓝型油菜品种(系)。采用苯磺隆耐性度量值(T值)、平均隶属函数值(ASF值)、加权耐性系数(WTC值)等指标及相关分析、频数分析、主成分分析、灰色关联度分析、聚类分析和逐步回归分析相结合的方法, 鉴定萌发期耐性。通过11份供试材料相对根长的方差分析, 确定了油菜萌发期耐苯磺隆种质资源筛选及评价研究的最佳苯磺隆浓度为25 mg kg ^-1。在此浓度胁迫下, 241份甘蓝型油菜的根长、芽长、率、发芽势、鲜重5个指标均存在显著性差异。根据T值的聚类分析, 将供试种质划分为5个苯磺隆耐性级别, 其中I级3份、II级30份、III级198份、IV级6份、V级4份。对苯磺隆耐性较强的甘蓝型油菜品种(系)为希望106、SWU95和WH-33, 可作为甘蓝型油菜苯磺隆耐性育种和耐性机制研究的重要资源。根长、鲜重、发芽率可作为评价油菜种质资源萌发期耐性的指标性状。

Screening and Comprehensive Evaluation of Germplasm Resources with Tribenuron-methyl Tolerance at Germination Stage in Rapeseed (Brassica napus L.)

The purpose of this study is to explore the characteristics of tribenuron-methyl tolerance in different genotypes of Brassica napus, and establish the evaluation system for screening and breeding new cultivars with tribenuron-methyl tolerance. The germination vigor was measured on the third day after treatment and the germination rate, shoot length, root length, dry weight, as well as fresh weight were measured on the seventh day. The identification of tolerance at germination stage was performed by tribenuron-methyl tolerance comprehensive evaluation value (T), average subordinative function value (ASF) and weight tribenuron-methyl tolerance coefficient (WTC) in correlation analysis, frequency analysis, principal component analysis, grey analysis, cluster analysis and stepwise regression analysis. Based on the variance analysis of relative root length index in 11 tested materials, we determined the optimum treatment concentration (25 mg kg ^-1) for selecting and evaluating the tolerant germplasm resources to tribenuron-methyl in napeseed. Under the optimum concentration, the single factor variance analysis showed significant differences in root length, shoot length, germination rate, germination vigor and fresh weight among 241 accessions of Brassica napus. The clustering analysis according to T value exhibited that the tested cultivars were roughly divided into five tribenuron-methyl tolerance grades, including three in grade I, 30 in grade II, 198 in grade III, six in grade IV, and four in grade V. We conclude that the varieties (lines) with strong tribenuron-methyl tolerance at germination stage are Xiwang 106, SWU95, and WH-33, which could be used as the germplasm materials for the study on tolerance breeding and mechanism. Furthermore, the root length, fresh weight and germination rate could be used as index traits to evaluate the tolerance of rapeseed germplasm resources during germination stage.