College of Horticulture and Plant Protection, Henan University of Science and Technology, Luoyang, China.
GreenLight Biosciences, Research Triangle Park, NC, U.S.A.
Phytopathology. 2024 Oct;114(10):2351-2359. doi: 10.1094/PHYTO-05-24-0172-R. Epub 2024 Oct 7.
is a devastating fungal pathogen that infects both maize and sorghum, leading to severe leaf diseases of the two crops. According to host specificity, pathogenic isolates of are divided into two formae speciales, namely f. sp. and f. sp. . To date, the molecular mechanism underlying the host specificity of is marginally known. In this study, the whole genomes of 60 isolates collected from both maize and sorghum were resequenced, which enabled identification of 233,022 single-nucleotide polymorphisms (SNPs) in total. Phylogenetic analysis indicated that all isolates are clustered into four genetic groups that have a close relationship with host source. This observation is validated by the result of principal component analysis. Analysis of population structure revealed that there is obvious genetic differentiation between two populations from maize and sorghum. Further analysis showed that 5,431 SNPs, including 612 nonsynonymous SNPs, are completely co-segregated with the host source. These nonsynonymous SNPs are located in 539 genes, among which 18 genes are predicted to encode secretory proteins, including six putative effector genes named , , , , , and . Sequence polymorphism analysis revealed various numbers of SNPs in the coding regions of these genes. These findings provide new insights into the molecular basis of host specificity in .
是一种破坏性的真菌病原体，感染玉米和高粱，导致这两种作物严重的叶片病害。根据宿主特异性， 的致病分离物分为两个专化型，即 f. sp. 和 f. sp. 。迄今为止， 宿主特异性的分子机制知之甚少。在这项研究中，对来自玉米和高粱的 60 个分离物的全基因组进行了重测序，总共鉴定出 233022 个单核苷酸多态性（SNP）。系统发育分析表明，所有分离物都聚类为四个遗传群，与宿主来源密切相关。这一观察结果得到了主成分分析结果的验证。群体结构分析表明，来自玉米和高粱的两个群体之间存在明显的遗传分化。进一步的分析表明，有 5431 个 SNP，包括 612 个非同义 SNP，与宿主来源完全共分离。这些非同义 SNP 位于 539 个基因中，其中 18 个基因被预测为分泌蛋白编码基因，包括六个假定的效应基因，分别命名为 、 、 、 、 和 。这些基因的编码区存在各种数量的 SNP。这些发现为 宿主特异性的分子基础提供了新的见解。
