联合连锁定位与GWAS剖析红掌抗相似穿孔线虫的遗传基础

Anthurium (Anthurium andraeanum L.) is one of the most popular potted and cutted flowers among the ornamental crops. But serious devastation caused by burrowing nematode (Radopholus similis) was prevalent in the anthurium industry. For the deficiency of resistant varieties, burrowing nematode not only reduces anthurium productivity, but also is regarded as a security risk to national agricultural production system, because of its widespread distribution resulted from the long distance transmission of infested plants..This research procedures will be to: 1) Evaluate diverse accessions of anthurium for resistance to burrowing nematode by artificial inoculation. 2) Large-scale single nucleotide polymorphism (SNP) discovery by using genotyping-by-sequencing strategy. 3) Assess the population structure and genome-wide association studies (GWAS) for nematode resistance in anthurium panel. 4) Identify the highly favorable SNP alleles and candidate genes associated with nematode resistance..The results will provide new insights into the genetic resistance to burrowing nematode in A. andraeanum, and facilitate the gene cloning and marker-assisted selection in breeding program. Moreover, the developed platform for gene mapping will be served as a powerful genetic tool for other key traits in anthurium research.

红掌是最主要的盆栽和切花园艺作物之一，但生产中遭受相似穿孔线虫的严重危害，该线虫不仅重创产业自身健康发展，而且伴随活体种苗和商品花大范围传播，给我国农业系统安全生产带来很大风险。目前红掌抗线虫资源发掘尚未开展，缺少抗性品种。本研究拟：1）接种评价红掌种质资源的线虫抗性；2）采取简化基因组测序，高通量开发红掌SNP标记；3）评价自然群体遗传结构及全基因组关联分析(GWAS)鉴定线虫抗性位点；4）验证红掌种质中的线虫抗性相关SNPs。研究结果将获得现有种质资源中的抗源基因数量、效应及等位基因SNP标记等信息，有助于抗线基因的分离和抗线虫分子辅助育种。同时，该分析体系将构建崭新的红掌基因定位与资源发掘平台，提高对众多重要性状相关基因的鉴定和利用能力。

红掌（Anthurium andraeanum. Lind）是我国重要的盆切两用花卉，生产中常常遭受相似穿孔线虫的危害，培育高抗疫病的品种是育种的主要目标之一。本研究广泛评价了红掌现有种质的线虫抗性水平，并结合连锁和关联分析，挖掘抗性遗传位点，主要研究结果如下：..（1）通过红掌种质资源广泛收集、接种鉴定和统计分析，了解现有种质的抗线虫性水平，通过病情指数和虫量综合评价，筛选出Midori、Acropolis、Cherry Red等高抗品种，Hot lip、Purple baby、White Champion、Vito等抗性品种，以及Red Success、Pink Champion、Dakota、祝福等高感品种，为抗性育种及病理学研究提供了基础材料。.（2）借助抗感遗传分离群体，在第12连锁群236M位置鉴定到一个主效QTL，命名为RsR1，LOD值为44.54，贡献率达到33.2%，两侧紧密连锁分子标记分别M12225和M13128之间，可用与辅助育种。.（3）构建了关联群体核心库，分别完成了简化基因组测序分析、SNP 分型、连锁不平衡衰减（LD decay）分析、群体进化和结构分析、PCoA分析等。用于鉴定抗线虫性关联位点，筛选连锁共有等位基因。..研究结果为红掌抗性遗传解析及抗病育种提供了基础信息，对其他性状的研究和育种也有借鉴意义。