Phytopathology (1996) 86, p. S68 (Woloshuk et al.)

C.P. Woloshuk and Jessica Garner (1996)
Inducers of aflatoxin biosynthesis are degradation products in maize kernels
Phytopathology 86 (11 suppl.), S68-S68
Abstract: Aspergillus flavus causes ear rot of maize. Associated with this disease is the mycotoxin aflatoxin. The goal of our research is to identify metabolites in maize kernels that induce aflatoxin biosynthesis in A. flavus. Using a GUS-reporter gene bio-assay, an aflatoxin-inducing activity was detected in extracts from ground maize kernels colonized by the aflatoxin-producing strain NRRL 3357. One set of the components responsible for the inducing activity are the products of starch degradation (glucose, maltose and maltotriose) due to a fungal amylase. Several reports indicate that, upon infection of maize kernels by A. flavus the fungus preferentially colonizes the embryonic tissue. Although starch is the primary component of the endosperm, as much as 8 to 10 percent of the dry weight of the embryo is starch. Our data support the hypothesis that, after colonization of the embryo, A. flavus produces an extracellular amylase that supplies fermentable sugars, resulting in the induction of aflatoxin biosynthesis.
Database assignments for author(s): Charles P. Woloshuk

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
molecular biology - genes

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Aspergillus flavus (plant/storage disease)	Maize/corn (Zea mays)