云南高产生境下影响油菜DH株系收获指数的相关性状筛选

Related traits affecting harvest index of rapeseed DH lines under high yield habitat of Yunnan Province

采用高、低收获指数材料纯合自交系G25和H008杂交,然后小孢子培养获得200份DH株系材料,在丽江和临沧两个云南早熟油菜高产生境下种植,应用相关分析和通径分析,从各生育阶段时间长度、初花期和成熟期干物质重量、不同部位角果数和角粒数、单株产量、千粒重、小区实收产量和籽粒含油量等17个性状中筛选与籽粒产量收获指数(YHI)关系密切的性状,为高收获指数油菜品种选育提供依据。结果表明,临沧育苗移栽高产生境下,营养体健壮,生物产量高、花期长,特别是一次分枝和二次分枝的角果数多,是单株产量和单位面积产量高的主要因素。丽江直播栽培高产生境下,油菜苗期长而花期短,营养体不足,主花序角果多而分枝角果少,一次分枝角果数和角粒数、二次分枝角粒数、单株角果数、单株产量和含油量与收获指数均达到极显著正相关,培育壮苗提高单株经济性状水平,可进一步提高单株产量和单位面积产量,进而提高收获指数。云南高产生境下,单株产量对收获指数有密切相关的正向效应,初花期干物质产量有密切的负向效应,一次分枝和二次分枝的角果数变幅大,通过品种和栽培技术调控,控制初花期干物质产量、保持合理的一次分枝角果数、二次分枝角果数和千粒重,获得较高的单株籽粒产量,是提高云南高产生境下油菜收获指数的有效策略。

Promotion of yield and oil output were restricted by the factor of lower harvest index.In this study,200 DH(double haploid)population and parents,G25(high-harvest-index inbred line)and H008(low-harvest-index inbred line)were planted in Lijiang and Lincang that both are rape-producing area of early maturing and high yield in Yunnan.The traits closely related to grain yield and harvest index(YHI)were screened from 17 traits including length of growth period,yield per plant,1 000 grain weight,actual harvest of experimental plots and oil content of grain.The results showed that there were higher yield per plant and yield per unit area resulting from strong vegetative organ,long flowering time and especially more siliques of primary and secondary bra-nches in seedling transplantation area of Lincang.However,excessive vegetative body and excessive number of pod were not conducive to increasing rape harvest index.In direct seeding area of Lijiang,rape seedlings are long and short flowering period,lack of vegetative body.The number of main inflorescence of the horn fruit was greater and the number of branch fruit was fewer in Lijiang.The following six traits were significantly positively correlated with harvest index,and these traits were pod number and kernels of primary branch,kernel number of secondary branch,single plant pod number,yield per plant and oil content.Cultivation of strong seedlings could improve the economic characteristics of single plant,yield per plant,yield per unit area and the harvest index.Under the high yield habitat of Yunnan,yield per plant favours the harvest index.Dry matter yield at early flowering stage has a negative effect on harvest index.The variation of the pod number of primary and secondary branches between different materials varied gready.It is an effective strategy to improve rape harvest index in high yield habitat in Yunnan,and these included controlling dry matter yield at early flowering stage,maintaining reasonable pod number of primary and secondary branch and thousand grain weight.