Podridão peduncular em manga: Patogenicidade, agressividade e caracterização de isolados pela análise isoenzimática

Abstract

Thirty-four Lasiodiplodia theobromae isolates collected from different organs of mango trees, in two different seasonal periods, at different geographical regions, were evaluated for pathogenicity, aggressiveness and production of enzymes on specific solid substrates and in polyacrylamide gel systems. Regardless of the organ from which they were collected, all isolates were pathogenic when inoculated into mango, differing in the aggressiveness degree, based on which they were separated into three groups: high, medium and low aggressiveness. The amylolytic, cellulolytic, lipolytic and proteolytic activities were estimated by means of enzyme diffusion on specific solid medium and measurement of the substrate degradation halo. The activities of enzymes á-esterase, â-esterase, leucineaminopeptidase, acid phosphatase and total protein were analyzed on polyacrylamide gels with specific revelation media for each analysis. The electrophoretic patterns and the analysis of extracellular enzymes showed polymorphism, evidencing the diversity in the genetic basis of isolates, regardless of collection period, geographic region and organ from which the isolates were collected.