Triticeae Research Institute, Sichuan Agricultural University, Chengdu, 611130, China.
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan Agricultural University, Chengdu, 611130, China.
Theor Appl Genet. 2022 Aug;135(8):2849-2860. doi: 10.1007/s00122-022-04154-4. Epub 2022 Jul 8.
A co-located KL and TKW-related QTL with no negative effect on PH and AD was rapidly identified using BSA and wheat 660 K SNP array. Its effect was validated in a panel of 218 wheat accessions. Kernel length (KL) and thousand-kernel weight (TKW) of wheat (Triticum aestivum L.) contribute significantly to kernel yield. In the present study, a recombinant inbred line (RIL) population derived from the cross between the wheat line S849-8 with larger kernels and more spikelets per spike and the line SY95-71 was developed. Further, of both the bulked segregant analysis (BSA) and the wheat 660 K single nucleotide polymorphism (SNP) array were used to rapidly identify genomic regions for kernel-related traits from this RIL population. Kompetitive Allele Specific PCR markers were further developed in the SNP-enriched region on the 2D chromosome to construct a genetic map. Both QKL.sicau-SSY-2D for KL and QTKW.sicau-SSY-2D for TKW were identified at multiple environments on chromosome arm 2DL. These two QTLs explained 9.68-23.02% and 6.73-18.32% of the phenotypic variation, respectively. The effects of this co-located QTL were successfully verified in a natural population consisting of 218 Sichuan wheat accessions. Interestingly, the major QTL was significantly and positively correlated with spike length, but did not negatively affect spikelet number per spike (SNS), plant height, or anthesis date. These results indicated that it is possible to synchronously improve kernel weight and SNS by using this QTL. Additionally, several genes associated with kernel development and filling rate were predicted and sequenced in the QTL-containing physical intervals of reference genomes of 'Chinese spring' and Aegilops tauschii. Collectively, these results provide a QTL with great breeding potential and its linked markers which should be helpful for fine mapping and molecular breeding.
利用 BSA 和小麦 660K SNP 阵列，快速鉴定出一个与 KL 和 TKW 相关的 QTL，该 QTL 对 PH 和 AD 没有负面影响。在 218 个小麦品系的小组中验证了其效果。小麦（Triticum aestivum L.）的粒长（KL）和千粒重（TKW）对粒产量有重要贡献。在本研究中，开发了一个来自具有较大籽粒和更多小穗每穗的小麦系 S849-8 和系 SY95-71 的重组自交系（RIL）群体。进一步，使用来自该 RIL 群体的两种 bulked segregant analysis（BSA）和小麦 660K 单核苷酸多态性（SNP）阵列，快速鉴定与粒相关性状的基因组区域。在 SNP 富集区域进一步开发了 Kompetitive Allele Specific PCR 标记，以构建遗传图谱。在 2DL 染色体臂上的多个环境中鉴定了 QKL.sicau-SSY-2D 用于 KL 和 QTKW.sicau-SSY-2D 用于 TKW。这两个 QTL 分别解释了 9.68-23.02%和 6.73-18.32%的表型变异。该共定位 QTL 的效应在由 218 个四川小麦品系组成的自然群体中得到了成功验证。有趣的是，主 QTL与穗长呈显著正相关，但对小穗数每穗（SNS）、株高或开花期没有负面影响。这些结果表明，通过使用该 QTL，有可能同步提高粒重和 SNS。此外，在“中国春”和粗山羊草参考基因组的 QTL 含物理区间中预测和测序了与籽粒发育和灌浆率相关的几个基因。总之，这些结果提供了一个具有巨大育种潜力的 QTL 及其连锁标记，这对于精细图谱和分子育种应该是有帮助的。
