title: Genetic differentiation and recombination among geographic populations of the fungal pathogen Colletotrichum truncatum from chili peppers in China.
abstract: Colletotrichum truncatum is an extremely important fungal pathogen. It can cause diseases both in humans and in over 460 plant species. However, little is known about its genetic diversity within and among populations. One of the major plant hosts of C. truncatum is pepper, and China is one of the main pepper-producing countries in the world. Here, we propose the hypotheses that geography has a major influence on the relationships among populations of C. truncatum in China and that infections in different populations need to be managed differently. To test these hypotheses, we obtained and analyzed 266 C. truncatum isolates from 13 regions representing the main pepper-growing areas throughout China. The analysis based on nine microsatellite markers identified high intrapopulation genetic diversity, evidence of sexual recombination, and geographic differentiation. The genetic differentiation was positively correlated with geographic distance, with the southern and northern China populations grouped in two distinct clusters. Interestingly, isolates collected from the pepper-breeding center harbored the most private alleles. The results suggest that the geographic populations of C. truncatum on peppers in China are genetically differentiated and should be managed accordingly. Our study also provides a solid foundation from which to further explore the global genetic epidemiology of C. truncatum in both plants and humans.
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Yongzhao
authors: Y
authors: Diao
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Can
authors: C
authors: Zhang
authors: Department of Biology, McMaster University Hamilton, ON, Canada.
authors: Jianping
authors: J
authors: Xu
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Dong
authors: D
authors: Lin
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Li
authors: L
authors: Liu
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Olivo G
authors: OG
authors: Mtung'e
authors: Department of Plant Pathology, College of Agriculture and Biotechnology, China Agricultural University Beijing, China.
authors: Xili
authors: X
authors: Liu
keywords: Colletotrichum truncatum; clustering analyses; genetic differentiation; phylogeny; population structure; private alleles