基于多重相关RIL群体的玉米株高和穗位高QTL定位

QTL Mapping for Plant Height and Ear Height by Using Multiple Related RIL Populations in Maize

株高和穗位高是玉米育种中的重要农艺性状。本研究利用我国玉米育种中骨干亲本黄早四与来自不同杂种优势群的其他11个骨干自交系组配11个RIL群体,开展基于单环境、联合环境的QTL分析,分别检测到269个和176个QTL。通过区段整合,检测到21个株高主效QTL及15个穗位高主效QTL,这些QTL分布在第1、第2、第3、第6、第7、第8、第9、第10染色体上。相对于共同亲本黄早四而言,部分QTL在不同RIL群体中的效应方向一致,来自共同亲本黄早四的等位基因在不同群体中能够稳定地表达。同时,还分别定位到在多环境下稳定表达的5个株高、4个穗位高"环境钝感QTL"。此外,进一步鉴定出5个重要的株高和穗位高QTL富集区段(bin 1.01 1.02,1.08 1.11,3.05,8.03 8.05和9.07),这些区段均包含多个株高和穗位高相关QTL,如bin3.05位点包含7个QTL,bin8.03 8.05位点分别包含9个QTL,且这些QTL至少在3个不同环境中能够被检测到,这些区域对QTL的精细定位和克隆有重要参考价值。

Plant height and ear height are two important agronomic traits in maize. In this study, 11 RIL populations developed by crossing a common parent （Huangzaosi, a foundation inbred line of maize breeding in China） with other 11 elite inbred lines were applied to QTL mapping for plant height and ear height based on phenotype data of three locations in two years. A total of 269 QTL detected by single-environment analysis and 176 QTL by joint analysis were identified across all of six environments, re- spectively. Collectively, 21 major-effect QTL for plant height and 15 major effect QTL for ear height were detected, which were located on chromosome. 1, 2, 3, 6, 7, 8, 9, and 10. It was found that the common parent （Huangzaosi） contributed the positive alleles for some QTL across different RIL populations. Five and four environment-insensitive QTL for plant height and ear height were also identified, respectively. Five QTL clustering regions related to plant and ear height, such as binl.01-1.03, 1.08-1.11, 3.05-3.06, 8.03-8.05, and 9.07, were dissected, of which each region were covered under more than three environments. These genomic regions would be valuable for fine mapping and cloning of height related QTL in maize.