油菜DH株系主要性状与收获指数的相关及通径分析

摘要

[Objective]The study aims to reveal the relationship between harvest index and the main agronomic traits of DH lines,which could provide scientific basis for high harvest index breeding by anther culture in Brassica napus.[Method] DH lines obtained from cross of two inbred lines which showed significant difference in harvest index were used as research materials.8 agronomic traits and harvest index were investigated,and the software DPS 7.05 was used for correlation and path analysis.[Result] All the data of 8 agronomic traits showed normal distribution in DH lines.And larger standard deviation and larger coefficient variation were also observed in these data.The harvest index was very significantly positively correlated with economical yield of single plant,very significantly negatively correlated with plant height and significandy negatively correlated with effective branch height.The rank of contribution rates of 8 traits for harvest index were the number of seed per pod,the number of first effective branch,thousand seeds weight,the number of effective siliques per plant,the effective branch height and plant height.The direct effect of number of seed per pod,the number of first effective branch and thousand seeds weight were positively correlated with harvest index,and the direct effect of number of effective siliques per plant,the effective branch height and plant height were negatively correlated with yield.[Conclusion] Harvest index as quantitative trait controlled by multiple genes could be promoted by hybridization focusing on reducing the height of plant and the first effective branch in Brassica napus.Higher yield of individual plant could be achieved by combining desirable traits such as multiple braches,more pods per plant and more seeds per pod,all of which were established on the fundament of corresponding vegetative body.We should pay more attention on breeding and regulating the traits of seed number per pod,number of the first effect branches and thousand seeds weight and consider other traits in oilseed rape breeding and cultivation.%[目的]明确DH株系收获指数与主要经济性状的相关关系,为利用小孢子培养创制油菜高收获指数育种材料提供科学依据.[方法]以收获指数存在显著差异的纯合自交系杂交、小孢子培养获得的DH株系为材料,用DPS7.05统计分析软件进行8个性状与产量收获指数的相关分析和通径分析,得到各性状因子对DH株系收获指数的直接影响及其通过其他性状因子对DH株系收获指数的间接影响大小,找出直接影响DH株系收获指数的主要性状因子.[结果]油菜DH群体主要性状基本满足正态分布趋势,且出现较大的分离,都存在较大的标准差及变异系数;收获指数与单株经济产量呈极显著正相关,与植株高度呈极显著负相关,与有效分枝高度呈显著负相关;对收获指数的直接贡献大小依次为每角粒数＞第一次有效分枝数＞千粒重＞单株有效角果数＞有效分枝高度＞植株高度,每角粒数、第一次有效分枝数、千粒重的直接效应对收获指数有正向作用,单株有效角果数、有效分枝高度、植株高度的直接效应对产量有负向作用.[结论]油菜收获指数属多基因控制的数量性状、亲本间杂交可筛选出高收获指数的品系和育种材料,提高油菜收获指数重点是降低植株高度和有效分枝高度,收获更多的单株商品油菜籽产量.而单株商品油菜籽产量的获得关键是通过品种选育聚合多分枝、多角、多粒的优良性状,同时需要有相应的营养体作为支撑.在栽培和育种过程中重视对每角粒数、第一次有效分枝数、千粒重的选择与调控,并兼顾其他性状是提高油菜产量和收获指数的重要途径.