杂交一代作图群体大小对茶树QTL效应估计的影响  

Impact of Population Size on QTL Mapping in a F_1 Population of Tea plants(Camellia sinensis)

作　　者：彭敏[1] 徐礼羿 王丽鸳 韦康[2,3] 成浩 谭礼强[1] PENG Min;XU Li-yi;WANG Li-yuan;WEI Kang;CHENG Hao;TAN Li-qiang(College of Horticulture,Sichuan Agricultural University,Chengdu 611130;Z Key Laboratory of Tea Plant Biology and Resources Utilization,Ministry of Agriculture,Hangzhou 31000;Tea Research Institute,Chinese Academy of Agricultural Science/National Center for Tea Improvement,Hangzhou 310008)

机构地区：[1]四川农业大学园艺学院,成都611130 [2]农业部茶树生物学与资源利用重点实验室,杭州310008 [3]中国农业科学院茶叶研究所/国家茶树改良中心,杭州310008

出　　处：《植物遗传资源学报》2018年第6期1143-1148,共6页Journal of Plant Genetic Resources

基　　金：现代农业产业技术体系建设专项(nycytx-23);四川省科技计划项目(2017JY0124)

摘　　要：利用杂交一代(F_1)作图群体进行遗传定位是研究茶树数量性状的重要手段,然而F_1群体大小对定位有显著影响。本研究以327份龙井43×白毫早F_1群体及它们的春季发芽期、新梢颜色和叶形指数3个性状的田间观测数据为基础,采用随机抽样的方法生成60个不同大小的作图群体(n=50,100,150,200,250,300),并利用基于SSR分子标记的连锁图谱进行QTL定位分析,以探讨F_1群体大小对茶树QTL定位结果的影响。结果表明QTL效应估计受群体大小的影响显著;当群体达150份时可基本保证检出效应在10%以上的QTL,但并不能实现对QTL效应值的准确估计,且最高与最低估计值相差可达2. 83倍。因此在研究和育种工作中,建议在条件允许的情况下应尽量扩大作图群体,对于从较小F_1群体中得到的QTL效应值应谨慎对待。Using F1 population for QTL mapping is an important strategy to study quantitative traits of tea plants. However the results are largely influenced by the size of population. In this study, sixty F1 populations with different sizes （n =50,100,150,200,250,300） were generated by randomly sampling from an original population （N = 327）,which was derived from a cross of ＇ Longjing43 ＇ × ＇ Baihaozao＇. By integrating a SSR-based genetic map and phenotype data of three traits （timing of spring bud flush, young shoot color and leaf shape index） , QTL mapping was performed in all populations. The results showed that the size of population results in a significant influence on estimation of phenotypic variation explained （PVE）. When more than 150 F1 individuals were ap- plied,QTLs with an effect of 〉 10% were found. Notably,the estimation of QTL effect value remained un-preeise, since 2. 83-fold difference on estimated effect was observed between the highest and lowest values. Therefore, a lar- ger size of population is suggested for precisely effect estimation, and QTLs identified from a small F1 population can be employed with caution in the marker-assisted breeding.

关 键 词：茶树 F1群体大小 QTL定位 效应估计 

分 类 号：S571.1[农业科学—茶叶生产加工]