Evaluación de la patogenicidad de tres aislados de (Fusarium spp.) asociados con el sistema radicular en mora (Rubus glaucus benth) en inverdero.

Abstract

This investigation aims to evaluate the pathogenicity of three isolates of Fusarium spp. associated with the root system of blackberry. For this purpose, blackberry plants located in San Luis parish, Chimborazo province with symptoms associated with wilting, crown necrosis and root system necrosis, symptoms present in different areas of the crop, were sampled. A collection of fungal isolates was obtained from the affected tissue in the crown of the collected plants and identification was carried out by means of morphological, cultural and molecular characteristics. Molecular analysis was performed by total DNA amplification technique, the fragments of the ITS rDNA and 1- α(TEF1-α) regions were amplified and sequenced, and then individual phylogenetic trees were carried out, using additional sequences from the GenBank of Fusarium spp. The pathogenicity evaluation was carried out in greenhouses with 7-month-old plants and inoculation was performed with the three ones isolates identified with a concentration of 1x10 conidio* using two methods (inoculation to the test substrate and immersion plus damage to the root system). Morphological and cultural characteristics identified Fusarium spp. gendre was identified and by means phylogenetic analyses F. oxysporum, F. redolens and F. solani were identified. Inoculated plants showed similar symptomatologies with each Fusarium species, causing leaf wilting and necrosis of the vascular tissue at the crown level. There was no significant difference in the progress of the disease among the inoculation methods,. It is concluded that Fusarium inoculated species cause wilting and root necrosis. The pathogenic activity of F. solani and F. redolens is reported for the first time in Ecuador in the blackberry crop. It is recommended to implement disease management measures by means this study.