Molecular characterization and phylogenetic analyses of Lophodermella needle pathogens (Rhytismataceae) on Pinus species in the USA and Europe

PeerJ

article

Jessa P. Ata¹  Kelly S. Burns³  Suzanne Marchetti³  Isabel A. Munck⁴  Ludwig Beenken⁵  James J. Worrall³  Jane E. Stewart² 

[1] Department of Forest Biological Sciences, University of the Philippines Los Baños, College;Department of Agricultural Biology, Colorado State University;Forest Health Protection;Northeastern Area State & Private Forestry;Swiss Federal Institute for Forest, Snow and Landscape Research WSL

关键词: Pine;    Needle;    Phylogeny;    Pathogen;    Morphology;    Molecular;   

DOI  :  10.7717/peerj.11435

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Increasing prevalence of conifer needle pathogens globally have prompted further studies on pathogen identification and a better understanding of phylogenetic relationships among needle pathogens. Several Lophodermella species can be aggressive pathogens causing needle cast in natural pine forests in the USA and Europe. However, their relationships with other Rhytismataceae species have historically been based on similarities of only limited phenotypic characters. Currently, no molecular studies have been completed to elucidate their relationships with other Lophodermella needle pathogens. This study collected and sequenced three gene loci, namely: internal transcribed spacer, large ribosomal subunit, and translation elongation factor 1-alpha, from five Lophodermella needle pathogens from North America (L. arcuata, L. concolor, L. montivaga) and Europe (L. conjuncta and L. sulcigena) to distinguish phylogeny within Rhytismatacaeae, including Lophophacidium dooksii. Phylogenetic analyses of the three loci revealed that all but L. conjuncta that were sampled in this study consistently clustered in a well-supported clade within Rhytismataceae. The multi-gene phylogeny also confirmed consistent nesting of L. dooksii, a needle pathogen of Pinus strobus, within the clade. Potential synapomorphic characters such as ascomata position and ascospore shape for the distinct clade were also explored. Further, a rhytismataceous species on P. flexilis that was morphologically identified as L. arcuata was found to be unique based on the sequences at the three loci. This study suggests a potential wider range of host species within the genus and the need for genetic characterization of other Lophodermella and Lophophacidium species to provide a higher phylogenetic resolution.

【 授权许可】

CC BY