摘要：
To pinpoint genetic model of cucumber (Cucumis sativus) internode length and function mode of gene,and also to evaluate the genetic effect and heritability of major genes and minor genes,two culcmber parents with significantly different internode length,namely ‘SJ57-h’ (short internode,P1'hereinafter) and ‘SJ11-1’ (long internode,‘P2’ hereinafter),were used to generate F1、B1、B2 and F2 populations for joint analysis.Mixed major-gene plus polygenes inheritance model were used to genetic law of internode length in both spring and autumn seasons.The results showed that the best fitted genetic model for cucumber internode size in both autumn and spring was D-0 model which internode length was controlled by one pair of additive-dominant-major genes plus additive-dominant-epitasis polygenes.Moreover,progeny internode length was closer to long-internode parent P2,namely,the progenies has long-internode parent heterosis.In spring,the major gene heritability of B1,B2 and F2 populations were estimated to be 68.5％,36.2％ and 56.3％,respectively,while the heritability of polygene was 0.6％,17.1％ and 0.6％,respectively.The variance of environment accounted for an average of 40.2％ of the phenotypic variation among three generations.In autumn,heritability of the major gene among B1,B2 and F2 generations was estimated as 68.5％,40.5％,65.1％,while the heritability of polygene was 1.2％,40.6％ and 5.4％,respectively.Environment variance accounted for about 26.3％ of the phenotypic variation.These results indicated that cucumber internode length was mainly controlled by a pair of major genes while the internode length was also obviously affected by environment factors in the B2 generation.Selection efficiency of major genes was relatively high in early generation of F2 and B1,whereas for selection efficiency of polygene was higher in B2 generation.Therefore,the trait of cucumber internode length was suitable for selection in early generation.The finding in the study will lay a theoretical foundation for breeding new cucumber vareties with improved plant architecture.%为了明确黄瓜(Cucumis sativus)节间长性状的遗传模型与基因的作用方式,并估测其主基因、多基因遗传效应与遗传率,利用短节自交系SJ57-h为P1和长节自交系SJ11-1为P2构建6世代遗传群体,在春秋两季种植,采用主+多基因遗传分析方法,开展节间长性状的遗传研究.研究结果显示,两季节间长受1对加性-显性-主基因+加性-显性-上位性多基因控制(D-0模型),且均偏向长节间亲本优势,长短更趋近于SJ11-1亲本.春季B1、B2、F2三个分离世代的主基因遗传率分别为68.5％、36.2％和56.3％,多基因遗传率分别为0.6％、17.1％和0.6％,环境变异平均值占表型变异的比例平均为40.2％;秋季B1、B2、F2三个分离世代的主基因遗传率分别为68.5％、40.5％、65.1％,多基因遗传率分别为1.2％、40.6％和5.4％;环境变异平均值占表型变异的比例为26.3％.表明黄瓜节间长受一对主基因控制,主基因在B1、F2世代选择效率高,B2世代加强多基因的选择,该性状受环境影响较大.节间长性状适宜在早期世代进行选择.本研究为黄瓜的株型改良育种提供了理论基础.
