INMIBO ( EX - PROPLAME)   14614
INSTITUTO DE MICOLOGIA Y BOTANICA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
The distribution and incidente of Neotyphodium endophytes from Argentina and its association with environmental factors
Autor/es:
CABRAL, D.; IANNONE L.J.; STEWART, A.; NOVAS, M.V.
Lugar:
New Zealand
Reunión:
Simposio; Proceedings of the 6th Internacional Symposium on Fungal Endophytes of Grasses; 2007
Resumen:
This paper will review the distribution and incidence of Neotyphodium endophytes in native grasses from Argentina, South America. In this country, native and naturalised grasses are widespread and are an important source of genetic variability that can be used in genetic programs of forage plants. The presence of Neotyphodium-infected plants has been recognised during the past twenty years. Endophytes have been found in 38 native host species of 6 genera, but toxicity problems to grazing animals have been observed only in three host species. The endophytes of several host species have been isolated and characterised by means of culture descriptions, antifungal resistance, isozymes and DNA markers. We have investigasted the association between Neotyphodium incidence and biotic and abiotic factors in populations of several native hosts located in different ecological regions. The results show a positive correlation between incidence and stressful environmental conditions. However, under extreme environmental conditions where plant growth is restricted endophyte infection is rare or absent. We also studied the multitrophic interaction between endophytes, grasses and arbuscular mycorrhiza fungi, finding a positive correlation between the fungal symbionts. Responses to endophytic infection in native grasses may vary with each association and may not always provide a selective advantage to the host. The study of the endophyte incidence allows us to evaluate the parameters and limits of the beneficial symbiosis to the host and to identify the agronomic attributes of the studied grasses.