遗传解析西藏半野生小麦和优异普通小麦品系后代的农艺性状

Genetic Analysis of Agronomic Traits for the RIL Population Derived between Tibet Semi-Wild Wheat and A Local Wheat Line

【目的】分析西藏半野生小麦Q1028和优异普通小麦品系99E18及其构建的重组自交系群体主要农艺性状的遗传特性,鉴定携带西藏半野生小麦优异性状的株系。【方法】采用西藏半野生小麦和优异普通小麦品系99E18构建的含287个株系的重组自交系(recombinant inbred line,RIL)为实验材料,进行两年田间调查和室内考种,对群体的抽穗期、开花期、株高、分蘖数、穗长、小穗数、穗密度、穗粒数、穗粒重以及千粒重等10个农艺性状进行考察及遗传分析。【结果】除分蘖数以外,两年间的表型数据均呈现出极显著正相关。10个测量性状在小麦RIL群体内部变异较大,表现出连续变异,呈近似正态分布,并由多基因控制。除分蘖数遗传力较低外(0.097),其余农艺性状遗传力均在0.3以上之间,由遗传因子控制。RIL群体中,大部分性状之间都检测到显著相关性。【结论】鉴定获得具有西藏半野生小麦背景的7个综合农艺性状较为优异的高代株系,适用于后期育种利用。

【Objective】The objective was to study the genetic characteristics of the agronomic traits for the recombinant inbred line(RIL)population constructed by crossing two a Tibet semi-wild wheat,Q1028 and a local wheat line,99E18,and further to identify lines with outstanding agronomic traits.【Method】The RIL and their parents were measured and evaluated for 10 agronomic traits includingheading date,flowering date,plant height,tiller number,spike length,spikelet number per spike,spike density,kernel number per spike,kernel weight per spike and thousand kernel weight in two growing seasons.【Result】The results showed all the investigated traits except tiller number were significantly correlated between two growing seasons.The ten measured traits in RIL population varied in a given growing season and they showed continuous variation with approximately normal distributions indicating that they are quantitative in nature.Except tiller number(0.097),all the other traits'heritability was larger than 0.3 indicating that the traits are stable and mainly controlled by genetic factors.In addition,correlation analysis showed that most of the studied traits of the RIL population showed significant correlations with each other.【Conclusion】A comprehensive analysis identified seven lines with better performance in agronomic traits and these lines with genetic background of Tibet semi-wildwheat could be used in the following breeding programs.