Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, 12# Zhongguancun Nandajie, Beijing 100081, China.
Beijing Vegetable Research Center, Beijing Academy of Agriculture and Forestry Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops (North China), Ministry of Agriculture, 50# Zhanghua Street, Beijing 100097, China.
Sci Rep. 2017 Feb 6;7:41696. doi: 10.1038/srep41696.
Elite parental lines are of great significance to crop breeding. To discover unique genomic loci associated with excellent economic traits in the elite cabbage inbred-line '01-20', we performed comparisons of phenotypes as well as whole-genome insertion-deletion/simple sequence repeat loci between '01-20' and each of its five sister lines. '01-20' has a range of excellent agronomic traits, including early-maturing, and improvements in plant type and leaf colour. Eight unique loci were discovered for '01-20' and '01-07-258', another elite line similar to '01-20' at the whole-genome level. In addition, two excellent double-haploid lines derived from a cross of '01-20' also inherited these loci. Based on the quantitative trait locus association results, five of these loci were found to be associated with important agronomic traits, which could explain why the elite parent '01-20' possesses greener outer leaves, a more compact and upright plant-type, rounder head, shorter core length, and better taste. Additionally, some of these loci have clustering effects for quantitative trait loci associated with different traits; therefore, important genes in these regions were analysed. The obtained results should enable marker-assisted multi-trait selection at the whole-genome level in cabbage breeding and provide insights into significant genome loci and their breeding effects.
优良的亲本系对作物育种具有重要意义。为了在优良自交系‘01-20’白菜中发现与优良经济性状相关的独特基因组位点，我们对‘01-20’及其五个姊妹系之间的表型和全基因组插入缺失/简单重复位点进行了比较。‘01-20’具有一系列优良的农艺性状，包括早熟，以及株型和叶片颜色的改善。在‘01-20’和另一个与‘01-20’在全基因组水平上相似的优良自交系‘01-07-258’中发现了八个独特的位点。此外，来自‘01-20’杂交的两个优良双单倍体系也遗传了这些位点。基于数量性状位点关联结果，发现其中五个位点与重要的农艺性状相关，这可以解释为什么优良亲本‘01-20’具有更绿的外叶、更紧凑直立的株型、更圆的头部、更短的芯长和更好的口感。此外，这些位点中的一些对与不同性状相关的数量性状位点有聚类效应；因此，对这些区域的重要基因进行了分析。这些结果应该能够在白菜育种中实现全基因组水平的多性状标记辅助选择，并为重要基因组位点及其育种效应提供深入了解。
