Neotyphodium endophytes in the native grass Hordeum comosum from Patagonia (Argentina)

IANNONE L ; IRISARRI JGN; PEREZ LI ; GUNDEL PE

Lanzhou

Simposio; 8th International Symposium on Fungal Endophyte of Grasses; 2012

State Key Laboratory of Grassland Agro-ecosystems; Lanzhou University, China; Engineering Research Centre of Grassland Industry; Ministry of Education, China; Gansu Research and Development Centre for Grassland Industry; Gansu Provincial Government

In Argentina, Neotyphodium endophytes were isolated from 20 host species and other 16 grass species were reported to be associated with Neotyphodium like endophytes The hybrid Epichloë festucae x Epichloë typhina species and Neotyphodium tembladerae, seems to be the most common endophyte, infecting at least 19 grass species included in six genera, but other Neotyphodium species were also described. Hordeum comosum J. Presl., has been reported as a host grass but their endophytes species have not been isolated and characterized. In this work we study the endophytes species of Hordeum comosum performing a preliminary characterization of their incidence in natural populations and their phylogenetic relationships with other endophytes from Argentina. Plants and seeds of Hordeum comosum were collected in 9 different collection sites in western-central Patagonia among 42º00S and 46º00W, in the Occidental and Subandean phytogeographic districts of Patagonia. Seeds of at least 20 plants were collected in each site and endophyte incidence was evaluated by the inspection of thirty seeds under microscope. Endophytes were isolated from superficially sterilized seeds and leaf sheaths). The phylogenetic relationships of the endophytes of H. comosum with other endophytes from Argentina and other Hordeum species were studied. The incidence of endophytes in seeds of H. comosum populations ranged from 0 to 100%. Whereas endophyte incidence ranged from 74% to 100% in E+ populations, three populations were endophyte free. Two isolates were obtained from each population. All the isolates presented two alleles of each tubB and tefA genes indicating a hybrid origin. The phylogeny of tefA gene of the three isolates studied indicated that two isolates were close related to N. tembladerae. These preliminary results suggest a wider host range (20 species) for N. tembladerae, and suggest the existence of a new hybrid endophyte in Argentina.