普通小麦(Triticum aestivum)地方品种具备了对当地自然生态条件的较强适应性和与之相对应的生产潜力。因此,从地方小麦品种中挖掘产量、品质、抗病虫及耐逆等优良基因资源,扩大当前小麦育种亲本的遗传基础,历来受到小麦遗传育种学家的高度重视。本研究通过对64个四川小麦地方品种进行了2年3个环境的表型精准鉴定,并利用231个小麦产量与品质相关性状的一致性QTL区段中的SSR标记,通过关联分析揭示四川地方品种产量和品质相关性状的遗传特征。表型鉴定结果显示,这些地方小麦品种具有多花多粒、分蘖能力强、成穗率高等特性,总体上属于中筋或弱筋小麦,且有效分蘖数、株高、小穗密度、穗长、可育小穗数、沉降值等性状遗传力较高,达50%以上。关联分析鉴定出18个多环境下稳定表达的SSR位点,与产量和品质性状极显著关联,其中1个(Xgwm372)同时与产量性状和品质性状关联,4个(Xwmc112,Xcfd5,Xwmc317和Xgwm372)最为稳定,3个(Xcfd5,Xgwm328和Xbarc181)关联到新的产量性状。相关分析表明,穗长与小穗密度呈极显著负相关,且有2个共同关联标记(Xgwm328和Xcfd5)。还鉴定出2A染色体上的Xgwm448.Xgwm328-Xgwm372区段(8.0cM)在多环境下与穗长显著关联。上述SSR标记位点和区段为通过分子标记辅助选择手段利用和发掘四川小麦地方品种产量和品质优异相关基因或区段提供理论指导。
Wheat (Triticum aestivum) landraces have strong adaptability to the local natural ecological condition and corresponding production potential. Therefore, identifying good resources of production, quality, disease and insects resistance from wheat landraces, as well as expanding the current genetic basis of breeding parents, have been highly valued. In this study, the phenotypic data were obtained with 64 wheat landraces from Sichuan province which were grown in 3 environments across 2 years and 231 SSR markers were selected from meta-quantitative trait locus (MQTL) controlling yield or quality related traits, and association analysis was then used to reveal the genetic effect of wheat landraces from Sichuan province. Phenotype analysis showed that Sichuan landraces generally belong to medium-gluten or weak-gluten wheat, having the properties of floribunda, multiple seeds, high tillering ability and high earing rate. The heritability was high (~50%) in effective tiller number, plant height, spikelet density, spike length, fertile spikelet number and sedimentation value. A total of 18 SSR markers were associated with yield and quality related traits including one (Xgwm372) simultaneously associated with yield and quality traits, 4 (Xwmc112, Xcfd5, Xwmc317, and Xgwm372) significantly stable, and 3 loci (Xcfd5, Xgwm328, and XbarclS1) newly identified to be associated with yield traits. Negative correlations were found between spike length and spikelet density, with 2 common associated markers Xgwm328 and Xcfd5. Besides, the marker region Xgwm448-Xgwm328- Xgwm372 (8.0 cM) on chromosome 2A was associated with spike length in multiple environments. These results may facilitate the excavation and utilization of elite genes carried by Sichuan wheat landraces.