title: Increased frequency of self-fertile isolates in Phytophthora infestans may attribute to their higher fitness relative to the A1 isolates.
abstract: Knowledge of population dynamics of mating types is important for better understanding pathogen's evolutionary potential and sustainable management of natural and chemical resources such as host resistances and fungicides. In this study, 2250 Phytophthora infestans isolates sampled from 61 fields across China were assayed for spatiotemporal dynamics of mating type frequency. Self-fertile isolates dominated in ~50% of populations and all but one cropping region with an average frequency of 0.64 while no A2 isolates were detected. Analyses of 140 genotypes consisting of 82 self-fertile and 58 A1 isolates indicated that on average self-fertile isolates grew faster, demonstrated higher aggressiveness and were more tolerant to fungicides than A1 isolates; Furthermore, pattern of association between virulence complexity (defined as the number of differential cultivars on which an isolate can induce disease) and frequency was different in the two mating types. In A1 isolates, virulence complexity was negatively correlated (r = -0.515, p = 0.043) with frequency but this correlation was positive (r = 0.532, p = 0.037) in self-fertile isolates. Our results indicate a quick increase of self-fertile isolates possibly attributable to their higher fitness relative to A1 mating type counterpart in the field populations of P. infestans in China.
authors.affiliation: Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Shen
authors.affiliation: Xiangyang Academy of Agricultural Sciences, Xiangyang 441057, Hubei, P. R. China.
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Fang
authors.affiliation: Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Yang
authors.affiliation: Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Jia-Feng
authors.initials: JF
authors.lastname: Zhang
authors.affiliation: Fujian Key Lab of Plant Virology, Institute of Plant Virology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Dan-Li
authors.initials: DL
authors.lastname: Sun
authors.affiliation: Key Lab for Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian, 350002, P. R. China.
authors.forename: Jiasui
authors.initials: J
authors.lastname: Zhan
mesh_terms: D002681:China; D005298:Fertility; D055750:Phytophthora infestans / Q000472:pathogenicity / Q000502:physiology*; D012098:Reproduction; D011198:Solanum tuberosum / Q000382:microbiology; D014774:Virulence