骨干玉米自交系种子活力性状配合力及遗传参数分析

Analysis of Combining Ability and Genetic Parameters for Seed Vigor Traits in Elite Maize Inbred Lines

为了探明种子高活力玉米品种改良选育的亲本组配规律,选用10个骨干玉米自交系为母本,另9个为父本,通过不完全双列杂交(NCⅡ)设计,组配90个杂交组合,对百粒质量、标准发芽率、冷浸发芽率、种子浸出液电导率等4个与玉米种子活力密切相关的性状指标进行测定,计算配合力效应和遗传参数。结果表明,90个组合在4个性状之间均存在极显著差异,母本一般配合力(GCA)效应对百粒质量、冷浸发芽率有极显著影响,对标准发芽率有显著影响;父本GCA效应除对种子浸出液电导率影响不显著外,对其他性状都有极显著影响;特殊配合力(SCA)效应对各性状都有极显著影响。冷浸发芽率与标准发芽率和浸出液电导率存在极显著正相关关系,与百粒质量存在显著负相关关系,各性状的广义遗传力均大于84%。因此,在玉米种子高活力自交系改良中,冷浸发芽率可以在早代选择,标准发芽率和种子浸出液电导率宜在晚代选择,在玉米种子高活力组合选育中,选择SCA高的组合的同时应保证一个亲本具有较高的GCA效应,TCA决定着组合F1代种子活力的高低,可作为选育高活力杂交组合的理论依据之一。Xinzi3113、LM34F、516M、3564M和LH82等自交系GCA效应较高,是种子高活力育种中改良其他自交系和组配杂交种的优异材料。Xinzi3113×LH82和Xinzi3113×516M是优良的种子高活力杂交组合。

The purpose of this study is to find out the method for parent selection of high vigor inbred line with high vigor superior combination,and provide theoretical basis for breeding high vigor maize hybrid.Ten elite maize inbred lines were selected as the female parent,and 9 were used as the male parent.The incomplete diallel cross test(NCⅡ)was used to generate 90 crossed combinations.Seed vigor related to traits of 100-seed mass,standard germination rate,cold soak germination rate,and conductivity of seed extract were measured for analyzing combining ability effect and genetic parameter.The results of analysis of variance showed that these 90 combinations had extremely significant differences among the 4 tested traits.The general combining ability(GCA)both in female parent and male parent had extremely significant effect on 100-seed mass,cold soaked germination rate,and the standard germination rate,but had no effect on conductivity of seed extract.The special combining ability(SCA)from both female and male parent had significant effect on all the traits.Correlation analysis results showed that cold soaking germination rate had significantly positive correlation with standard germination rate and seed extract electrical conductivity,but had negative correlation with 100-seed mass.The general heritability for all traits were greater than 84%.Therefore,in the breeding of high vigor inbred lines,the cold soaking germination rate can be selected in the early generations,while the standard germination rate and conductivity of seed extract should be selected in the late generations.At least one parent of the high vigor combination is an inbred line with a higher GCA,and a combination with a high SCA should be selected.Total combining ability(TCA)determines seed vigor of the F1 generation of the combination,and can be used as a theoretical basis for breeding high vigor hybrid combinations.Xinzi 3113,LM34F,516M,3564M,and LH82 have high GCA effects,which are high-seed-vigor breeding materials and can be used directly to generate hybrids or used as donors to improve other inbred lines.Xinzi3113×LH82 and Xinzi3113×516M are excellent hybrid combinations with high seed vigor.