不结球白菜抽薹开花性状的主基因+多基因遗传分析

为了研究不结球白菜抽薹开花性状的遗传规律,并对其耐抽薹品种进行鉴定筛选,以不结球白菜易抽薹纯系M10-1和耐抽薹纯系M10-2杂交获得的6世代(P1、P2、F1、B1、B2和F2)群体为材料,利用植物数量性状主基因+多基因多世代联合分析的方法对不结球白菜抽薹性状(现蕾期)和开花性状(开花期)进行遗传分析。结果表明,控制抽薹性状的为2对加性-显性-上位性主基因+加性-显性多基因,并存在明显的加性、显性和上位性效应。其中,2对主基因的加性效应值均为正,显性效应值hb大于ha,且以第2对主基因的正向显性效应为主;抽薹性状存在较大的主基因加性×加性和显性×显性互作效应,以呈负向的多基因的加性效应为主。B1、B2和F2的主基因遗传率分别为83.83%、87.82%和88.31%,多基因遗传率均为0,主基因+多基因遗传率平均为86.65%,环境变异占表型变异平均为13.35%,说明抽薹性状主要受主基因控制,在育种上可以应用抽薹性状(现蕾期)作为不结球白菜耐抽薹性的鉴定标准,并可在早期世代对其耐抽薹性进行选择,且要注意一定的环境因素。开花性状与抽薹性状遗传相似,均受到2对主基因控制,但主基因+多基因遗传率平均为9.57%,而环境变异平均为90.43%,对开花的影响显著,说明开花性状与环境的互作效应非常明显,不适宜作为耐抽薹性的鉴定指标。利用本研究获得的抽薹性状作为不结球白菜耐抽薹性的鉴定指标,并应用于育种实践,对选育不结球白菜耐抽薹新品种,提高产量具有重要意义。

Inheritance of Major Gene Plus Polygene Underlying Bolting and Flowering Traits in Pak-choi

Genetic analysis of bolting and flowering traits in pak-choi could contribute to the identification for bolting-resistant cultivars of pak-choi.The mixed major gene plus polygene inheritance model was used to analyze the inheritance of bolting and flowering traits in pak-choi with six generations of early bolting variety M10-1 (P1),bolting variety M10 -2(P2) and their F1,B1,B2 and F2 generations.The results showed that bolting trait was mainly controlled by two major genes expressing in the mode of additive-dominant-epistatic effects,and the additive effects of the two major genes were similar.In addition,the second major gene was the main in the dominant effect.There were additive x additive interaction effect and dominant × dominant interaction effect of major gene,in which negative additive effects of polygene was the major effect.Heritabilities of major genes in B1,B2,and F2 generations were 83.83％,87.82％ and 88.31％,respectively,while those of polygene in B1,B2,and F2 generations were all 0,the average heritability of major genes and polygene was 86.65％.The rate of environmental variation was 13.35％ in the total phenotypic variance.The bolting trait in pak-choi was dominated by major genes,and that environmental factors played a key role in inheritance.Thus,the selection of bolting trait in pak-choi was effective in early generations.The flowering trait was similar to the bolting trait inheritance.Heritability of major genes was 9.57％ on average,and the average environmental variance was 90.43％.These findings revealed that the flowering trait in Pak-choi was greatly affected by environmental factors and that the flowering trait should not be considered as an identification indicator of bolting resistance in Pak-choi.