Authors: J M Torres H Calderón E RodríguezArango J G Morales R Arango
Publish Date: 2012/06/01
Volume: 133, Issue: 4, Pages: 887-898
Abstract
Black leaf streak or “black Sigatoka” is one of the most important diseases affecting bananas and plantains worldwide Very few studies have been published on the hostpathogen interaction of this pathosystem particularly at the molecular level The aim of this work was to analyze under controlled conditions the enzyme activity of peroxidase POX phenylalanine ammonia lyase PAL β1 3glucanase GLU and chitinase CHI as well as the production of H2O2 in banana plants infected with Mycosphaerella fijiensis Defence responses were examined and compared in a resistant Calcutta 4 and a susceptible Williams cultivar Plants were inoculated and tested for enzyme activity at 0 6 12 18 24 48 and 72 h after infection HAI and 6 9 12 15 and 18 days after inoculation DAI A rapid induction of PAL POX and GLU was observed in the resistant cultivar at 6–18 HAI as well as H2O2 production at 72 HAI In contrast in the susceptible cultivar induction of these enzymes was only observed from 6 DAI These results suggest that the first 72 HAI are important in determining the response of the host to the disease Further studies characterizing banana responses to M fijiensis at the early stages of the infection are necessary in order to better understand this hostpathogen interactionThis work was supported by the Instituto para el desarrollo de la Ciencia y la Tecnología “Francisco José de Caldas” Colciencias Colombia grants No 22131217825 and 221345221253 Corporación para Investigaciones Biológicas CIB and Dirección de Investigaciones Medellín DIME of the Universidad Nacional de Colombia sede Medellín The authors of this article wish to thank Professor Jairo Castaño from Universidad de Caldas for the Calcutta 4 plantlets used in this work
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