INMIBO ( EX - PROPLAME) 14614
INSTITUTO DE MICOLOGIA Y BOTANICA
Unidad Ejecutora - UE
artículos
Título:
In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn
Autor/es:
MARCELA GALLY; MAIRA L CARABAJAL; ARACELI MARCELA RAMOS; TATIANA ITZCOVICH; SZAPIRO GALA; LAURA LEVIN
Revista:
REVISTA ARGENTINA DE MICROBIOLOGÃA
Editorial:
ASOCIACION ARGENTINA MICROBIOLOGIA
Referencias:
Lugar: Buenos Aires; Año: 2016 vol. 48 p. 267 - 273
ISSN:
0325-7541
Resumen:
Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rotof many species. Damages caused in soybean and maize crops in Argentinaduring drought and hot weather have increased due its ability to surviveas esclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall degradingenzymes [pectinases (polygalacturonase and polymethylgalacturonase);cellulases (endoglucanase); hemicellulases (endoxylanase) and theligninolytic enzyme laccase] by several Argentinean isolates of M.phaseolina; and assessed the pathogenicity of these isolates as apreliminary step to establish the role of these enzymes in the M.phaseolina-maize interaction. The isolates were grown in liquid syntheticmedium supplemented with glucose, pectin, carboxymethylcellulose or xylanas carbon sources and/or enzyme inducers and glutamic acid as nitrogensource. Pectinases were the first cell wall degrading enzymes detectedand the activities obtained (Polygalacturonase activity was between 0,4and 1,3 U/ml and Polymethylgalacturonase between 0,15 and 1,3 U/ml) werehigher than that of cellulases and xylanases, which appeared later and ina lesser magnitude. This sequence would promote initial tissue macerationfollowed by cell wall degradation. Laccase was detected in all theisolates evaluated (activity was between 36 U/l and 63 U/l).Aggressiveness of the isolates was tested in maize, sunflower andwatermelon seeds, being high on all the plants assayed. This studyreports for the first time the potential of plant cell wall degradingenzyme production in submerged fermentation, by different isolates of M.phaseolina.
