Key message

Identification of an EST-SSR molecular marker associated with Blister blight, a common fungal disease of tea, facilitating marker-assisted selection, marking a milestone in tea molecular breeding.

Abstract

lister blight (BB) leaf disease of tea, caused by the fungus Exobasidium vexans, results in 25–30% crop loss annually. BB is presently controlled by Cu based fungicides, but genetic resistance is the most viable option in disease management. Tea is a naturally out-crossing, woody perennial necessitating a long time for completion of a breeding programme. Marker-assisted selection (MAS) is vital to expedite breeding programmes and also for better accuracy in gene identification. The aim of the current research was to derive marker-trait associations using an F₁ population segregating for BB. The population was genotyped at 11 expressed sequence tag simple sequence repeat loci followed by detecting the alleles by fragment analysis. The genotypic and phenotypic data were subjected to single-marker analysis resulting in the identification of EST-SSR073 as a diagnostic marker amplifying three alleles of the sizes, 168, 170 and 190 bp in F₁. Of them, alleles 190 and 168 bp were confirmed to concur BB resistance and susceptibility, respectively. The alleles were validated in a panel of 64 tea cultivars, resulting in the amplification of 12 alleles at EST-SSR073. The EST-SSR073 allele sequences matched with Camellia sinensis photosystem-I reaction center subunit-II. The marker EST-SSR073 can be effectively used in breeding tea against BB, recording a milestone in MAS in tea.

中文翻译：

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一种检测茶（Camellia sinensis L.）抗水疱病抗病性的功能分子标记物

关键信息

鉴定出与茶叶常见真菌病害白斑病相关的EST-SSR分子标记，促进了标记辅助选择，标志着茶叶分子育种的里程碑。

抽象的

由真菌Exobasidium v​​exans引起的茶叶李斯特枯病 (BB) 叶病每年导致 25-30% 的作物损失。BB 目前由基于铜的杀菌剂控制，但遗传抗性是疾病管理中最可行的选择。茶是一种自然杂交的多年生木质多年生植物，需要很长时间才能完成育种计划。标记辅助选择 (MAS) 对于加快育种计划以及提高基因鉴定的准确性至关重要。当前研究的目的是使用 F _{1推导标记-性状关联}BB 的人口隔离。在 11 个表达的序列标签简单序列重复基因座处对群体进行基因分型，然后通过片段分析检测等位基因。_{对基因型和表型数据进行单标记分析，从而将 EST-SSR073 鉴定为在 F 1}中扩增三个大小为 168、170 和 190 bp 的等位基因的诊断标记。其中，190 和 168 bp 等位基因被证实分别具有 BB 抗性和易感性。这些等位基因在一组 64 个茶品种中得到验证，导致 EST-SSR073 上的 12 个等位基因扩增。EST-SSR073等位基因序列与山茶花匹配光系统-I 反应中心亚基-II。标记 EST-SSR073 可有效用于抗 BB 茶的育种，记录了茶中 MAS 的里程碑。