为解析甘蓝型油菜幼苗期下胚轴长、根长与成熟期主要农艺性状及品质性状的关系，以125份甘蓝型油菜品种（系）为材料，进行了室内和田间试验，并对幼苗期下胚轴长、根长与成熟期主要农艺性状及品质性状进行了相关性分析及灰色关联度分析。结果表明，甘蓝型油菜芥酸含量、硫甙含量变异系数较大，易受外界环境影响，而含油量、株高等变异系数较小，遗传力较高。幼苗期下胚轴长与根长呈极显著正相关，且与幼苗期根长关联度最大的也是幼苗期下胚轴长，幼苗期根长与倒伏级呈显著负相关。幼苗期下胚轴长、根长与主要品质性状均呈正相关，其中下胚轴长与芥酸含量呈显著正相关。可见，苗期根系越发达，成熟期抗倒伏性和品质性状越优良，选育抗倒伏和品质优的甘蓝型油菜时可将幼苗期下胚轴长与根长作为重要的参考指标。

 In order to dissect the relationship between hypocotyl length，root length at seedling stage and main agronomic traits and quality traits at maturity stage of Brassica napus,125 varieties (lines) of B.na pus were planted indoors and in field for investigating their agricultural traits and quality traits.Correlation and gray relational grade analyses were conducted among various traits.Results showed that the variation coefficients of erucic acid content and glucosinolate content were larger,susceptible to environmental im pact,while the variation coefficients of oil content,plant height were smaller and heritability was higher.The hypocotyl length and the root length at seedling stage was positively correlated with each other. The root length at seedling stage was significantly negative correlated with lodging grade.The length of hypo cotyl and root at seedling stage showed positive correlation with main quality traits and hypocotyl length was positivly correlated with erucic acid content(P＜0.05) .All the results indicated that when the roots of the seedlings were more developed，the lodging resistance and quality traits were better at maturity,and the hypocotyl length and root length at seedling stage could be used as important reference indexes for breeding B.napus with lodging resistance and high quality．