UNA MIRADA AL MOSAICO DE LA DIVERSIDAD GENÉTICA Y ENDOFÍTICA DEL BROMUS AULETICUS EN URUGUAY

CONDÓN, F; MENESES, L; IANNONE, L. J.; YOUNG C

Oro Verde

Congreso; XXXVIII Congreso de la Sociedad Argentina de Botánica; 2021

Sociedad Argentina de Botánica

Bromus auleticus Trin (ex Nees) is a perennial native grass, host of endophytes of the genusEpichloë. For the use and conservation of this symbiosis, its diversity was studied in 83 populationsfrom eight eco-geographic regions of Uruguay.Host diversity was analyzed by morpho-phenological and productive traits characterization in twocontrasting soils: shallow basaltic and deep sedimentary. The ecotypes existence was confirmed;accessions were discriminated by phenotype in accordance with agroecological origin, thus a particular/distinctive distribution pattern of genetic diversity was observed. Evidences of local adaptation were also found. Epichloë diversity was analyzedby morphological characterization, analysis of alkaloid biosynthesis genes, detection of peramine,chanoclavin I and ergovaline in leaves and quantification of the deterrent action against the ubiquitous aphid, Rhopalosiphum padi. Epichloë was detected in 70% of the populations, with incidences of 16 to 100%; nine genotypes with different potential toxicogenic capacities were identified. Four endophytic lineages were postulated, 2 of them not yet described. None of the populations tested produced mammalian-toxic ergot alkaloids and antiaphid action was associated with loline-producing genotypes. This study provides novel evidence thatUruguay native B. auleticus harbor Epichloë-endophytes that seem to be mammalian-safe, and thus,might be compatible with breeding programs due to their anti-aphid activity.