小麦温光敏雄性核不育系K78S及其衍生不育系的配合力分析

Combining Ability Analysis of Wheat Thermo-photo-sensitive Genic Male Sterile Line K78S and Its Derived Lines

为了评价小麦温光敏核不育系的配合力,采用14×6不完全双列杂交对14个温光敏核不育系和6个恢复系的7个性状进行了配合力分析。结果表明,穗粒数、千粒重、穗长和小穗数的一般配合力(GCA)方差达极显著水平,这些性状以加性效应为主;单株产量、单株穗数和株高的GCA和特殊配合力(SCA)方差均达极显著水平,3个性状同时受加性和非加性效应的共同作用。GCA好的亲本一般都有较大的产量及产量构成因子GCA效应值以及较多的正效GCA产量构成因子,不育系S1、S6、S7、S9、S12、S13、m14均具有较好的GCA。10个单株产量最大组合的产量构成因素SCA效应值分析结果表明,强优势组合产量三要素的重要性依次为穗粒数、有效穗数和千粒重,不育系的小穗数和株高,恢复系的单株穗数、穗粒数、千粒重及株高的田间表型值与其GCA效应值呈极显著正相关,这些性状的表型值可直接用于指导亲本选配。

84 hybrid F1 were produced with 14 thermo-photo-sensitive genic male sterile wheat lines and 6 restorers by 14×6 incomplete diallel cross,for the purpose of evaluating the combining ability of male sterile lines.The general combining ability（GCA） and special combining ability（SCA） of male sterile lines were investigated on 7 traits.The results showed that the variances of GCA in grains per spike,1000-grains weight,spike length and spikelet per spike were significant at 0.01 level,suggesting that these four traits were mainly determined by additive effects,while the variances of GCA and SCA in yield per plant,spikes per plant and plant height were both significant at 0.01 level,indicating both additive and non-additive effects played important roles for these three traits.Parents with better GCA were generally characterized as having bigger GCA values in yield and yield components,and more yield components with positive GCA value,such as male sterile lines S1,S6,S7,S9,S12,S13 and S14.According to the analysis on SCA effects of yield component from top ten combinations with the highest SCA value for yield component,grains per spike was the most important component for combination with strong heterosis,then the spikes per plant and 1000-grain weight.The result is helpful not only for selecting combination,but also for breeding sterile lines and restorers.Moreover,the phenotypic values of spikelet per spike and plant height of male sterile line,spikes per plant,grains per spike,1000-grain weight and plant height of restorer,were all positively and significantly correlated with their GCA values,which meant the phenotypic values of these traits could be directly used as a guide to combination selection.