Understanding plant root immunity against the global crop destroyer Macrophomina phaseolina using natural variation in Arabidopsis

由病原微生物如真菌和细菌引起的植物病害造成巨大的农业损失。被称为“全球农作物破坏者”的土传真菌病原体菜豆茎点霉（Macrophomina phaseolina）感染500多种植物物种的根部，包括许多经济上重要的作物。全球变暖促进了M.菜豆属由于对有毒熏蒸方法的限制，这种真菌造成的美国大田作物生产损失正在增加。因此，替代的，创新的方法，以减少造成的损害M。因此，迫切需要Phaseolina。植物对M.菜豆的免疫力知之甚少，根部的免疫力是一个研究不足的领域。利用模式植物拟南芥（Arabidopsis thaliana）在实验研究方面进展迅速的优势，对植物根系对M.将检查菜豆。这项研究预计将确定介导保护植物免受这种有害真菌侵害的基因和生物过程。本研究的结果将促进作物品种的开发，提高对M。菜豆属其最终目的是减少M.菜豆对美国经济的影响本研究将在UC滨江进行，这是一所西班牙裔服务机构，也是美国种族最多样化的研究型大学之一。研究人员致力于对历史上代表性不足的少数群体的成员进行科学培训。二倍体模式植物拟南芥为研究宿主对M.菜豆属拟南芥易于转化，具有全基因组范围的突变体和转基因集合，具有非常短的世代时间，并且在最小的空间中生长大量种群。一个特别有用的资源是收集了1000个天然A。基因组序列已经确定的拟南芥种质。在这个集合中，M.观察到菜豆属抗性，从而揭示有助于根对这种有害病原体的免疫的防御基因座和生物过程。本项目的中心假设是：拟南芥的自然变异将有助于发现根防御M的基本机制。菜豆属具体目标是：（1）利用A. thaliana的防御机制。菜豆属(2)研究抗M的根细胞类型特异性免疫应答。菜豆属(3)确定介导抗M保护的关键位点。菜豆属通过分析与M.菜豆抗蚜性A. thaliana加入的转录控制的调节，生理和生化过程中涉及宿主免疫力的描述。phaseolina将交付。使用根细胞类型特异性荧光标记线，不同的根组织如何运作，以介导对M。将提供菜豆。反向遗传学和基因图谱将确定有助于对M.该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Plant diseases caused by pathogenic microbes, such as fungi and bacteria, cause massive agricultural losses. Dubbed a “global destroyer of crops”, the soilborne fungal pathogen Macrophomina phaseolina infects the roots of more than 500 plant species including many economically significant crops. Global warming promotes the spread of M. phaseolina. Losses in US field crop production caused by this fungus are increasing due to restrictions on toxic fumigation methods. Thus, alternative, innovative methods to reduce damage caused by M. phaseolina are urgently needed. Plant defense processes against M. phaseolina are poorly understood and immunity in roots is an understudied area. Taking advantage of the model plant species Arabidopsis thaliana, which allows for rapid progress in experimental studies, the genetic basis of natural disease resistance in plant roots against M. phaseolina will be examined. This study is expected to identify genes and biological processes which mediate protection of plants against this detrimental fungus. Results from this study will accelerate the development of crop cultivars with enhanced disease resistance against M. phaseolina. Its ultimate goal is to reduce the negative impact of M. phaseolina on the U.S. economy. This study will be performed at UC Riverside, a Hispanic Serving Institution, and one of the most ethnically diverse research universities in the USA. The investigators are deeply committed to the scientific training of members of historically underrepresented minority groups.The diploid model plant Arabidopsis thaliana offers substantial advantages over crop systems to study the molecular genetic basis of host resistance against M. phaseolina. Arabidopsis is easily transformed, has genome-wide collections of mutants and transgenics, has a very short generation time, and large populations grow in minimal space. A particularly useful resource is a collection of 1000 natural A. thaliana accessions for which genome sequences have been determined. In this collection, a substantial degree of variation in M. phaseolina resistance is observed, allowing defense loci and biological processes contributing to root immunity against this detrimental pathogen to be uncovered. The central hypothesis of this project is: Natural variation in Arabidopsis thaliana will allow the discovery of fundamental mechanisms of root defenses against M. phaseolina. The specific aims being pursued are:(1) Use natural variation within A. thaliana to uncover defense mechanisms against M. phaseolina.(2) Study root cell type-specific immune responses against M. phaseolina.(3) Identify key loci mediating protection against M. phaseolina. By profiling transcriptional patterns associated with M. phaseolina resistance among A. thaliana accessions a description of transcriptionally-controlled regulatory, physiological, and biochemical processes involved in host immunity against M. phaseolina will be delivered. Using root cell type-specific fluorescent marker lines, information on how distinct root tissues operate to mediate protection against M. phaseolina will be provided. Reverse genetics and gene mapping will identify plant genes that contribute to immunity against M. phaseolina, which can be used to inform molecular genetic breeding approaches in crops.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.