Evaluación de la resistencia de seis variedades de trigo (Triticum aestivum L.) a tres cepas de Fusarium spp.

Abstract

In Ecuador, one of the factors that limit wheat production are diseases, one of the most important being the disease called “fusariosis” of the ear of wheat. This disease is caused by various species of the fungus Fusarium spp. This disease is of great economic importance because it can reduce production by more than 50%. The present research work was carried out in a greenhouse, in order to evaluate the resistance of six wheat varieties previously described as resistant to infection by three strains of Fusarium spp. The morphological characterization of the strains was carried out based on taxonomic keys and for molecular identification, PCR was used through the use of specific primers for Fusarium graminearum, defined in the galacto oxidase gene (gaoA). Punctual inoculation of three strains of Fusarium spp., was carried out in wheat ears at the anthesis stage. All the wheat varieties evaluated presented a reaction of resistance to Fusarium, also the three strains of Fusarium spp. were able to infect all wheat cultivars and induced the characteristic symptoms of Fusarium head blight (TEF). There were highly significant differences between the strains regarding the measurement of the incidence and severity variables. According to the cultural and morphological characteristics observed in carnation leaf agar medium (CLA), the three strains were identified within the genus Fusarium, but it was not possible to confirm to which species they belonged. There was no PCR amplification with the specific primers designed for F. graminearum.