小麦单交组合早代选择的遗传基础研究

GENETIC GROUNDS OF EARLY SELECTION FOR SINGLE CROSSES IN WHEAT

根据数量遗传学原理和杂交育种实践，并以１６个小麦单交组合为材料，探讨了Ｆ２代组合和单株选择的相对重要性以及Ｆ１组合评选的可行性和适宜参数。结果表明，Ｆ２代组合间Ｆ２和２ｓＦ２的标准差之比为１．３８，组合遗传力大于单株遗传力，说明Ｆ２代组合选择更为重要。Ｆ１与Ｆ２间相关系数高，（Ｆ１－ｍｉｎＦ１）２与ＶＦ２间相关性较好，证明在小麦育种中实施Ｆ１组合评选并淘汰一定量的组合是可行的。Ｆ１代组合评选可主要依据Ｆ１（或Ｆ１－ｍｉｎＦ１）并结合ＭＰ进行，依据Ｈ１评选Ｆ１组合可靠性差。

Based on principle of quantitative genetics,the importance of F 2 cross selection and the possibility of F 1 cross selection were studied by using materials of 16 single crosses in wheat yield breeding.High ratio (1.38) between standard variance of 2 and of 2×s F 2 ,and higher the heritability of F 2 for cross than for single plant showed that cross selection was more important than single plant selection in F 2 population.Good relative coefficients (r) between 1 and 2,( 1-min 1) 2 and V F 2 indicated that cross selection in F 1 generation could be carried out in program of wheat breeding. 1(or 1-min 1) and midparent values (MP) were suitable parameters for F 1 cross selection and heterosis (H 1) was not a good parameter.