米苦荞果壳率及其相关性状的遗传研究

Genetic Analysis of Fruit Hull Rate and Related Traits on Tartary Buckwheat

以薄壳黑米荞BRT2016-1和迟开裂型黑米荞BRT2016-2为母本、厚壳不落粒野苦荞WT2016-1和长黑粒苦荞T2016-1为父本,组配成3类杂交组合(A、B、C),对杂交组合F_2和F_3群体果壳率、粒长、粒宽、粒重、果仁重、粒长/粒宽(长/宽)6个目标性状进行广义遗传力、狭义遗传力、相关性和通径分析。结果表明,各组合果壳率广义遗传力平均为0.71,组合间变幅为0.42～0.91;狭义遗传力平均为0.18,组合间变幅为0.07～0.27;广义遗传力与狭义遗传力数值相差极大。与果壳率相关的5个目标性状(粒长、粒宽、粒重、果仁重、长/宽)组合间的广义遗传力分别为0.84、0.89、0.90、0.78、0.71,狭义遗传力分别为0.32、0.30、0.25、0.21、0.28。相关性分析表明,果壳率与粒长、粒宽、粒重的平均正相关性均达显著水平,其中,F_2植株中,平均相关系数依次为0.077、0.145、0.099;F_3家系中,平均相关系数分别为0.177、0.253、0.428。果壳率与果仁重在组合A和组合C中呈负相关关系,果仁重越大,果壳率越小。通径分析表明,粒重和果仁重对果壳率直接效应最大,前者为正效应,后者为负效应,两个性状5个组合的F_2植株平均直接效应分别为4.072、-4.087,平均间接效应分别为5.574、-5.570,F_3家系平均直接效应分别为1.284、-1.251,平均间接效应分别为2.526、-2.524,且间接效应均大于直接效应。因此,低果壳率的选择应着重考虑粒重、果仁重两个性状的效应,且需兼顾粒长、粒宽、长/宽性状的选择。

The thin-shell black rice lines BRT2016-1 and BRT2016-2 as the female parents were crossed with the thick-shell wild Tartary buckwheat accession WT2016-1 and common Tartary buckwheat line T2016-1 as the male parents,and five progenies populations including three crosses were produced for this study.The broadsense heritability,narrow-sense heritability,correlation and path analysis were for six target characters of F2 and F3 populations,including shell percentage,grain length,grain width,grain weight,kernel weight and length/width.Broadsense heritability of shell rate was 0.71,the range of broad-sense heritability was 0.42-0.91,indicating significant genetic effects.The average narrow-sense heritability was 0.18,and the variation combinations was 0.07-0.27.The difference between broad-sense heritability and narrow-sense heritability was very significant,suggesting great nonadditive genetic effects.Broad-sense heritability of 5 target characters(grain length,grain width,grain weight,kernel weight,length/width)related to fruit hull percentage were 0.84,0.89,0.90,0.78 and 0.71,respectively.Narrow-sense heritabilities were 0.32,0.30,0.25,0.21 and 0.28,respectively.Correlation analysis showed that there were significant average positive correlation between shell rate and grain length,grain width and grain weight,the average correlation coefficients of F2 plants and F3 families were 0.077,0.145,0.099 and 0.177,0.253,and 0.428,respectively.There was a negative correlation between shell rate and kernel weight in combination A and combination C,the bigger the kernel weight,the smaller the shell rate.Path analysis showed that grain weight and kernel weight had the greatest direct effect on shell percentage,the former had a positive effect and the latter had a negative effect.The average direct effects of the five hermaphroditic combinations were 4.072 and-4.087,and the average indirect effects were 5.574 and-5.57,the average direct effects of F3 families were 1.284 and-1.251,and the average indirect effects were 2.526 and-2.524,respectively.The indirect effects were greater than the direct effects,indicating that the influence factors of fruit shell percentage were caused by the effects of the target traits.Therefore,the effects of traits such as grain weight and kernel weight should be considered in the selection of low shell percentage,and the selection of grain length,grain width and length/width should be considered.