The epichloë endophytes are systemic, constitutive, and often vertically transmitted fungal symbionts of grass species in subfamily Poöideae. Prior studies indicate that several asexual epichloë endophytes (Neotyphodium species) have evolved directly from sexual (Epichloë) species, whereas others evolved by hybridization between two or more endophyte species. In this paper, we investigate the phylogenies of 27 Neotyphodium spp. isolates from 10 native grass species (in 4 tribes) in 22 populations throughout Argentina. Relationships among these fungi and a worldwide collection of epichloë endophytes were estimated by phylogenetic analysis of sequences from variable portions (mainly introns) of genes for β-tubulin (tub2) and translation elongation factor 1-α (tef1). Most of the Argentine endophyte isolates were interspecific hybrids of Epichloë festucae and E. typhina. Only one isolate was a hybrid of a different ancestry, and three isolates were apparently non-hybrid endophytes. These results indicate that interspecific hybridization, which promotes genetic variation, was common during the evolution of the endophytes of Argentine grasses.
|Number of pages||13|
|Journal||Molecular Phylogenetics and Evolution|
|State||Published - Apr 2005|
Bibliographical noteFunding Information:
This research was supported by CONICET and Universidad de Buenos Aires grants, PRHIDEB-CONICET (Publication No. 159), and by the Harry E. Wheeler Endowment to the University of Kentucky. A.G. held a fellowship from the Universidad de Buenos Aires. D.C. and M.S.R. are members of the Carrera del Investigador Científico, CONICET, Argentina. Sequence analysis was conducted at the University of Kentucky Advanced Genetic Technologies Center, supported by USDA-CSREES Grants 2000-34431-8975 and 2001-34457-10343, and USDA-NRI Grant 2002-35311-11716. We thank A. Leuchtmann for supplying cultures from Switzerland and elsewhere in Europe. We are grateful to A.D. Byrd, W. Hollin, K.G. Lindstrom, M.V. Novas, and C. Slamovits for able assistance.
- Endophyte phylogeny
- Hybrid fungi
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Molecular Biology