Abstract:
Cold stress is one of the main abiotic stresses that affects rice growth and production worldwide. Dissection of the genetic basis is important for genetic improvement of cold tolerance in rice. In this study, a new source of cold-tolerant accession from the Yunnan plateau, Lijiangxiaoheigu, was used as the donor parent and crossed with a cold-sensitive cultivar, Deyou17, to develop recombinant inbred lines (RILs) for quantitative trait locus (QTL) analysis for cold tolerance at the early seedling and booting stages in rice. In total, three QTLs for cold tolerance at the early seedling stage on chromosomes 2 and 7, and four QTLs at the booting stage on chromosomes 1, 3, 5, and 7, were identified. Haplotype and linear regression analyses showed that QTL pyramiding based on the additive effect of these favorable loci has good potential for cold tolerance breeding. Effect assessment in the RIL and BC3F3 populations demonstrated that qCTB1 had a stable effect on cold tolerance at the booting stage in the genetic segregation populations. Under different cold stress conditions, qCTB1 was fine-mapped to a 341-kb interval between markers M3 and M4. Through the combination of parental sequence comparison, candidate gene-based association analysis, and tissue and cold-induced expression analyses, eight important candidate genes for qCTB1 were identified. This study will provide genetic resources for molecular breeding and gene cloning to improve cold tolerance in rice.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s11032-024-01488-3.
摘要:
低温胁迫是影响水稻生长和产量的主要非生物胁迫之一。解剖遗传基础对于水稻耐寒性的遗传改良具有重要意义。在这项研究中,来自云南高原的新的耐寒来源,李江小黑谷,被用作供体亲本,并与冷敏感品种杂交,Deyou17,开发重组自交系(RIL),用于定量性状基因座(QTL)分析,以在水稻的幼苗和孕穗期进行耐寒性。总的来说,确定了2号和7号染色体上幼苗早期的三个耐冷性QTL,以及1号、3号、5号和7号染色体上孕穗期的四个QTL。单倍型和线性回归分析表明,基于这些有利位点的加性效应的QTL金字塔具有良好的耐寒育种潜力。在RIL和BC3F3种群中的效果评估表明,qCTB1在遗传分离种群的孕穗期对耐寒性具有稳定的作用。在不同的冷应激条件下,qCTB1精细映射到标记M3和M4之间的341kb间隔。通过亲本序列的组合比较,基于候选基因的关联分析,以及组织和冷诱导表达分析,确定了qCTB1的8个重要候选基因。本研究将为提高水稻耐寒性的分子育种和基因克隆提供遗传资源。
■在线版本包含补充材料,可在10.1007/s11032-024-01488-3获得。