Exploring virulence and mating in Colletotrichum lentis

探索 Colletotrichum lentis 的毒力和交配

• 批准号: RGPIN-2018-03768
• 负责人: Banniza, Sabine
• 金额: $ 5.83万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=763584
• 关键词: Exploring; virulence; mating; Colletotrichum; lentis

Colletotrichum lentis is a fungal pathogen that causes an important foliar disease on lentil. Infection, referred to as hemibiotrophic, is complex as C. lentis initially infects without being perceived by the plant (biotrophic phase) before aggressively killing host cells (necrotrophic phase). Understanding the biology of C. lentis in terms of its ecology and its interaction with lentil is the long-term objective of my research program. In the Canadian population, two races were described, the highly virulent race 0 and the weakly virulent race 1. In past research we succeeded in mating isolates of the two races and developed a large population of offspring isolates. The genome of C. lentis was sequenced and with the help of our population, we could arrange the genome into 12 linkage groups probably representing chromosomes. Based on subtle differences in the genetic make-up of the parents (molecular markers) across all chromosomes, we developed a genetic linkage map that can be used analogues to a road map for direction to identify genes involved in controlling traits such as virulence. Using our genetic map and our offspring population we associated differences in the presence of molecular markers among the individuals of the offspring with their virulence on a differential lentil variety. We also associated the markers with the ability to mate, as there are two mating groups in C. lentis, and only two individuals from different mating groups are fertile. We could thus identify one particular chromosomal region that is associated with virulence and another one associated with mating.These regions consist of many genes and are referred to as quantitative trait loci or QTLs. Not every gene in the QTL will be involved in regulating the trait of interest, so further research is needed to identify those that are. The short-term objectives of my program are therefore to identify and characterize the genes associated with the mating incompatibility QTL and the virulence QTL, and to compare Canada lentil isolates with a Chinese vetch isolate, the first foreign isolate of this species, in terms of mating and virulence. Identification of genes will be achieved by comparing the structure of genes with those that have already been associated with our traits in other species based on conserved features across species. Experiments then will assess whether these genes are affecting the trait by determining whether the fungus “switches on or off” a particular gene when it is infecting a lentil plant, and/or by disabling the candidate gene and assessing changes in the trait, e.g. a prevention of infection by the fungus or two previously fertile isolates becoming infertile. Understanding these traits will enable us to breed for better resistance in lentil varieties because we know what “weapons” C. lentis uses to successfully infect, and what the evolutionary potential of the fungal population is based on its mating system.

小扁豆炭疽菌是引起小扁豆叶部病害的一种病原真菌。感染，被称为半活体营养型，是复杂的，如C。晶状体最初感染而不被植物察觉（活体营养期），然后积极地杀死宿主细胞（坏死营养期）。了解C.扁豆的生态学及其与扁豆的相互作用是我研究计划的长期目标。在加拿大人群中，描述了两个小种，高毒力小种0和弱毒力小种1。在过去的研究中，我们成功地交配分离的两个种族，并开发了一个大的人口的后代分离物。C.在我们人类的帮助下，我们可以将基因组排列成12个连锁群，这些连锁群可能代表染色体。基于所有染色体上亲本遗传组成（分子标记）的细微差异，我们开发了一个遗传连锁图，可以类似于路线图，用于识别参与控制毒力等性状的基因。使用我们的遗传图谱和我们的后代人口，我们关联的差异存在的分子标记的后代个体与他们的毒力差异扁豆品种。我们还将这些标记与交配能力联系起来，因为在C中有两个交配组。扁豆，只有两个人从不同的交配组是可育的。因此，我们可以确定一个特定的染色体区域，与毒力和另一个相关的交配。这些区域由许多基因组成，被称为数量性状位点或QTL。并非QTL中的每个基因都参与调控感兴趣的性状，因此需要进一步的研究来确定那些基因。因此，我的计划的短期目标是识别和表征与交配不亲和QTL和毒力QTL相关的基因，并比较加拿大扁豆分离物与中国野豌豆分离物，该物种的第一个外国分离物，在交配和毒力方面。基因的识别将通过比较基因的结构与那些已经与我们的性状在其他物种的基础上跨物种的保守特征。然后，实验将通过确定真菌在感染小扁豆植物时是否“打开或关闭”特定基因来评估这些基因是否影响性状，和/或通过禁用候选基因并评估性状的变化，例如防止真菌感染或两个先前可育的分离株变得不育。了解这些特性将使我们能够在扁豆品种中培育更好的抗性，因为我们知道什么是“武器”C。lentis用来成功感染，以及真菌种群的进化潜力是基于其交配系统。