白菜类蔬菜资源的农艺性状分析及应用研究

通过对505份白菜类蔬菜：大白菜、小白菜和紫菜薹的田间观察鉴定，同时抽取其中有代表性的材料90份(每类型30份)以白菜型油菜(30份)为对照进行农艺性状考察，结果显示：白菜类蔬菜种质资源中存在有符合油莱育种目标的特异性状，如特早熟型、白花、黄籽、抗寒型、矮杆、多分枝、多角果、大粒、特殊不育类型等。从变异幅度看，白菜类蔬菜资源的大多数农艺性状的变异系数大于白菜型油菜。同时通过核心种质资源构建，从120份材料中筛选出40份(每类10份)进行系统聚类分析，结果将40份供试材料共分为12类，其中紫菜薹和白菜型油莱各聚为一类，而小白菜和大白菜的聚类结果比较复杂，类型较多，这说明白菜类蔬菜资源与普通白菜型油菜的亲缘关系较远，遗传背景差异较大，用它们测配杂交组合优势明显，这一点在实际应用中已被证实。同时通过对白菜类蔬菜不育系和甘蓝型油菜不育系接受外界花粉能力的比较得到，白菜类蔬菜不育系的异交率极高。这一特性为其杂交优势利用提供了科学依据。

Analysis and Exploitation of Agronomic Traits of Vegetable Germplasms of Brassica campestris

505 vegetable materials of Brassica campestris ,such as Chinese cabbage,no-heading Chinese-cabbage and purple Tsai-tai,were field observed and identified,and 90 materials of their representative types (30 materials per type) were sampled to investigate their agronomic traits in comparison with rapeseed materials of Brassica campestris .The results showed that the vegetable germplasms of Brassica campestris had unique agronomic traits,such as early maturity,white flowers,yellow seeds,cold resistance,short stem,high branching capability,high pod-setting capability,big seed size and exceptional sterility,which could satisfy the breeding goals of rapeseed.A majority of the vegetable materials of Brassica campestris had the agronomic traits that varied in CV more than those that the rapeseed materials of Brassica campestris did.Meantime,40 materials (10 materials per type) were screened from 120 materials for cluster analysis by constructing core germplasms and thus 40 materials were divided into 12 types,with purple Tsai-tai and the rapeseed materials of Brassica campestris falling into one type,and Chinese cabbage and no-heading cabbage complicatedly covered by quiet a few types,and this indicated the vegetable germplasms of Brassica campestris were genetically far from the rapeseed germplasms of Brassica campestris and thus their combinations had obvious advantages,which had been proven in actual practices.The comparison between the capabilities of the sterile lines of vegetables of Brassica campestris and the sterile lines of rapeseed of B.napus to accept xenogamous pollens showed that vegetables of Brassica campestris had a higher cross-pollination rate and this characteristic would provide scientific basis for heterosis exploitation.