School of Biological Sciences and Institute of Agriculture, The University of Western Australia, Crawley, WA, Australia.
Plant Molecular Biology and Biotechnology Laboratory, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Vic., Australia.
Plant Biotechnol J. 2019 Apr;17(4):789-800. doi: 10.1111/pbi.13015. Epub 2018 May 31.
Brassica oleracea is an important agricultural species encompassing many vegetable crops including cabbage, cauliflower, broccoli and kale; however, it can be susceptible to a variety of fungal diseases such as clubroot, blackleg, leaf spot and downy mildew. Resistance to these diseases is meditated by specific disease resistance genes analogs (RGAs) which are differently distributed across B. oleracea lines. The sequenced reference cultivar does not contain all B. oleracea genes due to gene presence/absence variation between individuals, which makes it necessary to search for RGA candidates in the B. oleracea pangenome. Here we present a comparative analysis of RGA candidates in the pangenome of B. oleracea. We show that the presence of RGA candidates differs between lines and suggests that in B. oleracea, SNPs and presence/absence variation drive RGA diversity using separate mechanisms. We identified 59 RGA candidates linked to Sclerotinia, clubroot, and Fusarium wilt resistance QTL, and these findings have implications for crop breeding in B. oleracea, which may also be applicable in other crops species.
甘蓝型油菜是一种重要的农业物种，包括许多蔬菜作物，如白菜、花椰菜、西兰花和羽衣甘蓝；然而，它可能容易受到各种真菌病的影响，如根肿病、黑胫病、叶斑病和霜霉病。对这些疾病的抗性是由特定的疾病抗性基因类似物（RGAs）介导的，这些基因在甘蓝型油菜品系中分布不同。由于个体之间存在基因的存在/缺失变异，测序的参考品种并不包含所有的甘蓝型油菜基因，这使得有必要在甘蓝型油菜泛基因组中寻找 RGA 候选基因。在这里，我们对甘蓝型油菜泛基因组中的 RGA 候选基因进行了比较分析。我们表明，RGA 候选基因的存在在品系之间存在差异，并表明在甘蓝型油菜中，SNP 和存在/缺失变异通过不同的机制驱动 RGA 多样性。我们鉴定了 59 个与核盘菌、根肿病和枯萎病抗性 QTL 相关的 RGA 候选基因，这些发现对甘蓝型油菜的作物育种具有重要意义，这也可能适用于其他作物物种。
