Abstract：
Understanding the genetic basis of how plants defend against pathogens is important to monitor and maintain resilient tree populations. Swiss needle cast (SNC) and Rhabdocline needle cast (RNC) epidemics are responsible for major damage of forest ecosystems in North America. Here we investigate the genetic architecture of tolerance and resistance to needle cast diseases in Douglas-fir (Pseudotsuga menziesii) caused by two fungal pathogens: SNC caused by Nothophaeocryptopus gaeumannii, and RNC caused by Rhabdocline pseudotsugae. We performed case-control genome-wide association analyses and found disease resistance and tolerance in Douglas-fir to be polygenic and under strong selection. We show that stomatal regulation as well as ethylene and jasmonic acid pathways are important for resisting SNC infection, and secondary metabolite pathways play a role in tolerating SNC once the plant is infected. We identify a major transcriptional regulator of plant defense, ERF1, as the top candidate for RNC resistance. Our findings shed light on the highly polygenic architectures underlying fungal disease resistance and tolerance and have important implications for forestry and conservation as the climate changes.
摘要：
了解植物如何抵御病原体的遗传基础对于监测和维持有弹性的树木种群非常重要。瑞士针铸造（SNC）和横纹肌针铸造（RNC）流行病是北美森林生态系统遭受严重破坏的原因。在这里，我们研究了由两种真菌病原体引起的道格拉斯冷杉（Pseudotsugamenziesii）对针管病的耐受性和抗性的遗传结构：由Nothophaeocryptopusgaeumannii引起的SNC，和由假糖横纹肌引起的RNC。我们进行了病例对照全基因组关联分析，发现道格拉斯冷杉的抗病性和耐受性是多基因的，并且在强选择下。我们表明，气孔调节以及乙烯和茉莉酸途径对于抵抗SNC感染很重要，一旦植物被感染，次生代谢物途径在耐受SNC中起作用。我们确定了植物防御的主要转录调节因子，ERF1，作为RNC抵抗的头号候选人。我们的发现揭示了真菌抗病性和耐受性的高度多基因结构，并随着气候变化对林业和保护具有重要意义。
