State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Chengdu 611130, China.
Triticeae Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
Int J Mol Sci. 2022 Jan 19;23(3):1052. doi: 10.3390/ijms23031052.
Spike-layer uniformity (SLU), the consistency of the spike distribution in the vertical space, is an important trait. It directly affects the yield potential and appearance. Revealing the genetic basis of SLU will provide new insights into wheat improvement. To map the SLU-related quantitative trait loci (QTL), 300 recombinant inbred lines (RILs) that were derived from a cross between H461 and Chinese Spring were used in this study. The RILs and parents were tested in fields from two continuous years from two different pilots. Phenotypic analysis showed that H461 was more consistent in the vertical spatial distribution of the spike layer than in Chinese Spring. Based on inclusive composite interval mapping, four QTL were identified for SLU. There were two major QTL on chromosomes 2BL and 2DL and two minor QTL on chromosomes 1BS and 2BL that were identified. The additive effects of , and were all from the parent, H461. The major QTL, and , were detected in each of the conducted trials. Based on the best linear unbiased prediction values, the two loci explained 23.97% and 15.98% of the phenotypic variation, respectively. Compared with previous studies, the two major loci were potentially novel and the two minor loci were overlapped. Based on the kompetitive allele-specific PCR (KASP) marker, the genetic effects for were validated in an additional RIL population. The genetic effects ranged from 26.65% to 32.56%, with an average value of 30.40%. In addition, showed a significant ( 0.01) and positive influence on the spike length, spikelet number, and thousand kernel weight. The identified QTL and the developed KASP marker will be helpful for fine-mapping these loci, finally contributing to wheat breeding programs in a marker-assisted selection way.
穗层整齐度（SLU），即穗在垂直空间分布的一致性，是一个重要的性状。它直接影响产量潜力和外观。揭示 SLU 的遗传基础将为小麦改良提供新的见解。为了定位与 SLU 相关的数量性状位点（QTL），本研究使用了来自 H461 和中国春杂交的 300 个重组自交系（RIL）。这些 RIL 及其亲本在来自两个不同试点的两个连续年份的田间进行了测试。表型分析表明，H461 在穗层垂直空间分布上比中国春更一致。基于包容复合区间作图法，共鉴定到 4 个与 SLU 相关的 QTL。在染色体 2BL 和 2DL 上鉴定到 2 个主效 QTL 和 1BS 和 2BL 上鉴定到 2 个微效 QTL。的加性效应均来自亲本 H461。在每个试验中都检测到主要 QTL 。基于最佳线性无偏预测值，这两个位点分别解释了 23.97%和 15.98%的表型变异。与先前的研究相比，这两个主要的 QTL 可能是新的，而两个微效 QTL 是重叠的。基于竞争等位基因特异性 PCR（KASP）标记，在另一个 RIL 群体中验证了 的遗传效应。遗传效应范围为 26.65%至 32.56%，平均值为 30.40%。此外，还表现出对穗长、小穗数和千粒重的显著（ 0.01）和正向影响。鉴定到的 QTL 和开发的 KASP 标记将有助于这些位点的精细定位，最终以标记辅助选择的方式为小麦育种计划做出贡献。
