利用简单序列重复标记揭示茶树品种的杂合性和遗传关系及其对育种和遗传图谱构建计划的意义

Heterozygosities and genetic relationship of tea cultivars revealed by simple sequence repeat markers and implications for breeding and genetic mapping programs.

作者信息

Tan L Q, Zhang C C, Qi G N, Wang L Y, Wei K, Chen S X, Zou Y, Wu L Y, Cheng H

机构信息

Tea Science Department, College of Horticulture, Sichuan Agricultural University, Ya'an, Sichuan, China.

National Center for Tea Improvement, Tea Research Institute, Chinese Academy of Agricultural Science, Hangzhou, Zhejiang, China.

出版信息

Genet Mol Res. 2015 Mar 6;14(1):1557-65. doi: 10.4238/2015.March.6.3.

DOI:10.4238/2015.March.6.3

PMID:25867299

Abstract

Genetic maps are essential tools for quantitative trait locus analysis and marker-assisted selection breeding. In order to select parents that are highly heterozygous for genetic mapping, the heterozygosity (HS) of 24 tea cultivars (Camellia sinensis) was analyzed with 72 simple sequence repeat markers. In total, 359 alleles were obtained with an average of 4.99 per marker. The HS varied greatly from 37.5 to 71.0% with an average of 51.3%. On average, tea cultivars from Fujian Province showed a higher level of heterozygosity (59.8%) than those from Zhejiang (48.5%) and Yunnan (44.5%), and the 12 national tea cultivars were generally more heterozygous than the 12 provincial cultivars. Unweighted pair-group analysis using the arithmetic average grouping divided the 24 cultivars into 2 groups that are consistent with the morphological classification. All dual combinations of the 24 cultivars were studied to calculate the percentage of mappable markers when using pseudo-testcross mapping strategy, and results showed that this value also varied greatly from 51.4 to 90.3%. The genetic relationships and HS differences among different cultivars were discussed, and tea cultivars with high HS were recommended as cross parents for genetic mapping programs.

摘要

遗传图谱是数量性状基因座分析和标记辅助选择育种的重要工具。为了选择用于遗传图谱构建的高度杂合的亲本，利用72个简单序列重复标记对24个茶树品种的杂合度（HS）进行了分析。共获得359个等位基因，每个标记平均有4.99个。HS变化很大，从37.5%到71.0%，平均为51.3%。平均而言，福建省的茶树品种杂合度水平（59.8%）高于浙江省（48.5%）和云南省（44.5%）的品种，12个国家级茶树品种通常比12个省级品种更杂合。采用算术平均法的非加权配对组分析将24个品种分为2组，这与形态学分类一致。研究了24个品种的所有双杂交组合，以计算使用伪测交作图策略时可作图标记的百分比，结果表明该值也有很大差异，从51.4%到90.3%。讨论了不同品种间的遗传关系和HS差异，并推荐高HS的茶树品种作为遗传图谱构建计划中的杂交亲本。