UN MÉTODO CROMATOGRÁFICO PARA DETECCIÓN TEMPRANA DE Fusarium graminearum EN CULTIVOS DE TRIGO

JUÁREZ M.PATRICIA; GIROTTI JUAN R; MALBRAN ISMAEL; LORI GLADYS

Congreso; X CONGRESO ARGENTINO DE MICROBIOLOGIA GENERAL SAMIGE; 2014

UN MÉTODO CROMATOGRÁFICO PARA DETECCIÓN TEMPRANA DE Fusarium graminearum EN CULTIVOS DE TRIGO A CHROMATOGRAPHIC METHOD FOR EARLY DETECTION OF Fusarium graminearum IN WHEAT CULTIVARS. M Patricia Juárez1 , Juan R Girotti1 , Ismael Malbrán2 , Gladys A Lori2 . 1 Instituto de Investigaciones Bioquímicas de La Plata - CONICET CCT La Plata - UNLP. 2 Centro de Investigaciones de Fitopatología - CIC - UNLP. mjuarez@isis.unlp.edu.ar In Argentina, Fusarium head blight (FHB) is a destructive disease of cereal grain crops, mainly in wheat crops. Fusarium species infect wheat during the flowering period. In addition to losses of yield, these fungi can also synthesize toxic components (mycotoxins) in suitable environmental conditions, thus threatening animal and human health. Fungi produce volatile organic compounds (VOC), during both primary and secondary metabolism, VOC appear as intermediate and end products of various metabolic pathways and belong to numerous structure classes such as mono- and sesquiterpenes, alcohols, ketones, lactones, esters or C8 compounds, which can be used for detection and identification. We investigated the potential of solid phase microextraction (SPME) coupled to capillary gas chromatography (CGC) and mass spectrometry (MS) to detect volatile precursors of mycotoxins released by Fusarium species. Fusarium graminearum was differentiated from F. poae, F. equiseti, F. verticillioides and F.oxysporum by comparison of the VOC profiles. Within trichotecene-producers, F. graminearum and group A fungi differed on the structure of their volatile sesquiterpenes. This methodology was also useful to predict the presence of F. graminearum in wheat cultivars, based on the detection of trichodiene (TRI), the volatile precursor of trichothecenes. TRI is a useful marker to detect toxigenic Fusarium in wheat spikes from live plants, regardless the actual development of Fusarium head blight (FHB) disease