高粱净光合速率的遗传分析

为筛选净光合速率配合力较高的亲本，选育高光效的高粱杂交品种，选用3 个高粱不育系和6 个恢复系，采用不完全双列杂交法，组配18 个杂交组合，在高粱抽穗期、开花期和灌浆期对亲本和杂交组合的净光合速率进行一般配合力(GCA)效应、特殊配合力(SCA)效应分析，并对高粱净光合速率与主要农艺性状和产量性状进行相关性遗传研究。结果表明，在高粱抽穗期、开花期和灌浆期不育系162273A净光合速率一般配合力均最高，其效应值分别为16.2706、9.7331 和11.9907，3 个不同时期净光合速率一般配合力最高的恢复系分别为16727、161011 和161026，其效应值分别为10.6624、23.7309、18.0146。3个不同时期高粱净光合速率特殊配合力最高的组合分别为162273A×16878、162279A×161026 和162279A×161026，其效应值分别为35.0123、19.9455 和33.0046。3 个不同时期高粱净光合速率加性方差与基因型方差比值较低，狭义遗传力也较低。相关性分析研究表明，灌浆期净光合速率与穗粒重、千粒重、籽粒产量、生物产量和收获指数均呈极显著正相关。

Genetic Ability of Net Photosynthesis Rate in Sorghum

To select parental lines and sorghum hybrid with high net photosynthesis rate, 18 crossing combinations were made by 3 sterile lines and 6 restorer lines with incomplete diallel cross method. The general combining ability (GCA) effect and special combining ability (SCA) effect of net photosynthesis rate on parental lines and crossing combination were analyzed at heading stage, anthesis stage and grain filling stage. Correlation analysis on net photosynthesis rate and main agronomic characters and yield were carried out. The results showed that the general combining ability of sterile line 162273A was the highest in net photosynthesis rate at heading stage, anthesis stage and grain filling stage, its relative effect value at these three stages was respectively 16.2706, 9.7331 and 11.9907. The general combining ability of restorer line 16727, 161011 and 161026 was the highest in net photosynthesis rate at the three growth stage respectively, with the relative effect value as 10.6624, 23.7309, and 18.0146. The special combining ability of crossing combination 162273A× 16878, 162279A×161026 and 162279A×161026 was the highest in net photosynthesis rate at the three growth stage respectively, with the relative effect value as 35.0123, 19.9455 and 33.0046. The ratio of additive genetic variance to genotype variance was low and the narrow-sense heritability was also low at the three growth stages. Correlation analysis showed that net photosynthesis rate had extremely significant positive correlation with grain weight per spike, 1000 grain weight, grain yield, biomass yield and the harvest index.