Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, 1 Airport Road, P.O. Box 1030, Swift Current, SK, S9H 3X2, Canada.
Department of Plant Sciences and Crop Development Centre, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada.
Theor Appl Genet. 2022 Apr;135(4):1143-1162. doi: 10.1007/s00122-021-03980-2. Epub 2022 Mar 20.
A major QTL on chromosome arm 4BS was associated with reduced spike shattering and reduced plant height in coupling phase, and a second major QTL associated with reduced spike shattering was detected on chromosome arm 5AL in the same wheat variety Carberry. Spike shattering can cause severe grain yield loss in wheat. Development of cultivars with reduced shattering but having easy mechanical threshability is the target of wheat breeding programs. This study was conducted to determine quantitative trait loci (QTL) associated with shattering resistance, and epistasis among QTL in the populations Carberry/AC Cadillac and Carberry/Thatcher. Response of the populations to spike shattering was evaluated near Swift Current, SK, in four to five environments. Plant height data recorded in different locations and years were used to determine the relationship of the trait with spike shattering. Each population was genotyped and mapped with the wheat 90 K Illumina iSelect SNP array. Main effect QTL were analyzed by MapQTL 6, and epistatic interactions between main effect QTL were determined by QTLNetwork 2.0. Correlations between height and shattering ranged from 0.15 to 0.49. Carberry contributed two major QTL associated with spike shattering on chromosome arms 4BS and 5AL, detected in both populations. Carberry also contributed two minor QTL on 7AS and 7AL. AC Cadillac contributed five minor QTL on 1AL, 2DL, 3AL, 3DL and 7DS. Nine epistatic QTL interactions were identified, out of which the most consistent and synergistic interaction, that reduced the expression of shattering, occurred between 4BS and 5AL QTL. The 4BS QTL was consistently associated with reduced shattering and reduced plant height in the coupling phase. The present findings shed light on the inheritance of shattering resistance and provide genetic markers for manipulating the trait to develop wheat cultivars.
一个位于 4BS 染色体臂上的主效 QTL 与降低抽穗期的穗部破碎和株高有关，在同一小麦品种 Carberry 中，5AL 染色体臂上检测到另一个与降低穗部破碎相关的主效 QTL。穗部破碎会导致小麦严重减产。减少破碎但易于机械脱粒的品种的开发是小麦育种计划的目标。本研究旨在确定与抗破碎性相关的数量性状基因座（QTL），以及 Carberry/AC Cadillac 和 Carberry/Thatcher 群体中 QTL 之间的上位性。在萨斯喀彻温省斯威夫特卡伦特的四个至五个环境中评估了群体对穗部破碎的反应。在不同地点和年份记录的株高数据用于确定该性状与穗部破碎的关系。每个群体都使用小麦 90K Illumina iSelect SNP 阵列进行基因型分析和作图。MapQTL 6 分析主效 QTL，QTLNetwork 2.0 确定主效 QTL 之间的上位性互作。高度和破碎之间的相关性范围从 0.15 到 0.49。Carberry 为两个主要 QTL 做出了贡献，这两个 QTL 与 4BS 和 5AL 染色体臂上的穗部破碎有关，在两个群体中都有检测到。Carberry 还在 7AS 和 7AL 上贡献了两个次要 QTL。AC Cadillac 在 1AL、2DL、3AL、3DL 和 7DS 上贡献了五个次要 QTL。鉴定出了 9 个上位性 QTL 相互作用，其中最一致和协同的相互作用是 4BS 和 5AL QTL 之间的相互作用，它降低了破碎的表达。4BS QTL 与降低抽穗期的破碎和株高有关。本研究结果阐明了抗破碎性的遗传机制，并为操纵该性状开发小麦品种提供了遗传标记。
