TY  - JOUR
A1  - Nowicki, Marcin
A1  - Hadziabdic, Denita
A1  - Trigiano, Robert N.
A1  - Boggess, Sarah L.
A1  - Kanetis, Loukas
A1  - Wadl, Phillip A.
A1  - Ojiambo, Peter S.
A1  - Cubeta, Marc A.
A1  - Spring, Otmar
A1  - Thines, Marco
A1  - Runge, Fabian
A1  - Scheffler, Brian E.
T1  - 'Jumping Jack': genomic microsatellites underscore the distinctiveness of closely related pseudoperonospora cubensis and pseudoperonospora humuli and provide new insights into their evolutionary past
T2  - Frontiers in microbiology
N2  - Downy mildews caused by obligate biotrophic oomycetes result in severe crop losses worldwide. Among these pathogens, Pseudoperonospora cubensis and P. humuli, two closely related oomycetes, adversely affect cucurbits and hop, respectively. Discordant hypotheses concerning their taxonomic relationships have been proposed based on host–pathogen interactions and specificity evidence and gene sequences of a few individuals, but population genetics evidence supporting these scenarios is missing. Furthermore, nuclear and mitochondrial regions of both pathogens have been analyzed using microsatellites and phylogenetically informative molecular markers, but extensive comparative population genetics research has not been done. Here, we genotyped 138 current and historical herbarium specimens of those two taxa using microsatellites (SSRs). Our goals were to assess genetic diversity and spatial distribution, to infer the evolutionary history of P. cubensis and P. humuli, and to visualize genome-scale organizational relationship between both pathogens. High genetic diversity, modest gene flow, and presence of population structure, particularly in P. cubensis, were observed. When tested for cross-amplification, 20 out of 27 P. cubensis-derived gSSRs cross-amplified DNA of P. humuli individuals, but few amplified DNA of downy mildew pathogens from related genera. Collectively, our analyses provided a definite argument for the hypothesis that both pathogens are distinct species, and suggested further speciation in the P. cubensis complex.
KW  - oomycete
KW  - obligate pathogens
KW  - downy mildew
KW  - speciation
KW  - evolution
KW  - genotyping
KW  - host specificity
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63338
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-633387
SN  - 1664-302X
N1  - This research was funded fully by the United States Department of Agriculture - Agricultural Research Service grant (NACA 58−6062−6) to RT.
VL  - 12
IS  - art. 686759
SP  - 1
EP  - 17
PB  - Frontiers Media
CY  - Lausanne
ER  -