大穗小麦穗部性状的遗传分析

Genetic Analysis on Spike Characteristics of Wheat Variety with Large Spike

为给大穗小麦材料在杂交育种中的利用提供参考,以小麦大穗品系9110192和多穗品系密穗矮秆为亲本,采用P1、P2、F1、F2四世代联合分析方法,研究了杂交后代穗长、小穗数、小穗密度、穗粒数、穗粒重的遗传模型。结果表明,穗长、小穗密度、穗粒数、穗粒重均受两对加性-显性-上位性主基因与多基因共同控制;小穗数为多基因遗传,无主基因存在,各性状均不同程度受环境影响。穗长、小穗密度、穗粒数、穗粒重主基因遗传率分别为92.14%、88.69%、62.71%、59.67%,多基因遗传率分别为2.58%、3.19%、11.87%、13.1%。穗长与小穗密度受环境影响较小,早代选择可靠性较高,穗粒数、穗粒重受环境影响较大,应在稍晚世代选择。

In the present work, the inheritance of five yield-related traits was analyzed by the joint seg- regation analysis with a mixed genetic model of major gene plus polygenes in four different generations （P1 , P2, F1 and F2） derived from a cross between large spike wheat line 9110192 and multi-spike line Misu（aigan. Results showed that, the spike length, compactness, grain number per spike and grain weight per ear were controlled by two pairs of major genes with significant additive-dominant-epistatic effects plus polygenes. The spikelet number was controlled by polygenes, and each character was in- fluenced by environment at a different extent. The heritability of major genes controlling spike length, compactness, grain number per spike, and grain weight per ear were estimated as 92.14%, 88.69%, 62. 71% and 59. 67%, respectively. However, the heritability of polygenes was about 2.58% ,3.19% ,11.87% and 13.1%. The spike length and compactness was less affected by environment, thus the early selection is suitable. Grain number per spike and grain weight per ear were high-ly affected by environment, and it is more efficient for selection in higher generations rather than selection in the lower generations.