Mapping QTL for seedling morphological and physiological traits under normal and salt treatments in a RIL wheat population
Mapping QTL for seedling morphological and physiological traits under normal and salt treatments in a RIL wheat population
复制标题
DOI：
10.1007/s00122-021-03872-5
复制
发表时间：
2021-06-06
影响因子：
5.4
通讯作者：
Zheng, Qi
中科院分区：
文献类型：
--
作者：
Luo, Qiaoling;Hu, Pan;Zheng, Qi
在一个RIL小麦群体中，对27个苗期性状在正常和盐处理下的遗传基础进行了全面的分析，并在另外两个遗传群体中验证了7个QTL区间。土壤盐分严重制约着小麦(Triticum aestivum L.)通过影响其增长和发展在全球范围内生产。为探讨小麦耐盐性的遗传基础，以高产小麦品种中麦175(ZM175)与耐盐品种小研60(XY60)杂交产生的重组自交系(RIL)群体为材料，在高密度遗传连锁图谱的基础上，定位了正常和盐处理下小麦苗期性状的QTL。共检测到27个形态和生理性状的158个稳定加性QTL，分布在除3A和4D以外的所有小麦染色体上。它们解释了2.35-46.43%的表型变异，LOD得分范围为2.61-40.38。XY60的等位基因对100个QTL的相应性状有正效应，ZM175的等位基因对其余58个QTL的相应性状有正效应。近一半的QTL(78/158)被定位在分别位于第2A、2B、2D、4B、5A、5B、5D和7D(2)染色体上的9个QTL簇上。为了验证分子标记辅助选择(MAS)的可靠性和潜力，在另外两个遗传群体中验证了7个QTL区间。除加性QTL外，还检测到94对上位性效应显著的QTL，其中20个QTL与处理互作。本研究全面阐明了小麦苗期性状(特别是与根系相关的性状)与耐盐性相关的遗传基础，所开发的与稳定QTL紧密连锁的竞争性等位基因特异的PCR标记将为小麦耐盐育种的分子标记辅助选择提供有力的支持。
Key message The genetic basis of 27 seedling traits under normal and salt treatments was fully analyzed in a RIL wheat population, and seven QTL intervals were validated in two other genetic populations. Soil salinity seriously constrains wheat (Triticum aestivum L.) production globally by influencing its growth and development. To explore the genetic basis of salt tolerance in wheat, a recombinant inbred line (RIL) population derived from a cross between high-yield wheat cultivar Zhongmai 175 (ZM175) and salt-tolerant cultivar Xiaoyan 60 (XY60) was used to map QTL for seedling traits under normal and salt treatments based on a high-density genetic linkage map. A total of 158 stable additive QTL for 27 morphological and physiological traits were identified and distributed on all wheat chromosomes except 3A and 4D. They explained 2.35-46.43% of the phenotypic variation with a LOD score range of 2.61-40.38. The alleles from XY60 increased corresponding traits for 100 QTL, while the alleles from ZM175 had positive effects for the other 58 QTL. Nearly half of the QTL (78/158) were mapped in nine QTL clusters on chromosomes 2A, 2B, 2D, 4B, 5A, 5B, 5D, and 7D (2), respectively. To prove the reliability and potentiality in molecular marker-assisted selection (MAS), seven QTL intervals were validated in two other genetic populations. Besides additive QTL, 94 pairs of loci were detected with significant epistatic effect and 20 QTL were found to interact with treatment. This study provides a full elucidation of the genetic basis of seedling traits (especially root system-related traits) associated with salt tolerance in wheat, and the developed kompetitive allele-specific PCR markers closely linked to stable QTL would supply strong supports to MAS in salt-tolerant wheat breeding.