Fumigating Crops with Fungus

BELTSVILLE, Md.Compounds emitted by the beneficial fungus Muscodor albus may offer a biologically based way to fumigate certain crops and rid them of destructive pests, according to Agricultural Research Service (ARS) studies that pitted Muscodor against potato tuber moths, apple codling moths and Tilletia fungi that cause bunt diseases in wheat. The separate studies had one goalto learn whether volatile organic compounds (VOCs) released by the fungus could replace or diminish the use of synthetic pesticides.

In lab tests, Muscodor VOCs were found to kill 100-percent of Tilletia spores. In field trials conducted since 2006, treating seed or soil with a ground-rye-grain formulation of Muscodor completely prevented common bunt under moderate disease conditions.

The dry formulation resembles granola with white frosting, said ARS plant pathologist Blair Goates. Adding water causes that frostingin actuality, a twisted mass of Muscodor fungal fibers called myceliato begin growing and emit the VOCs, which in turn, fumigate the seed and surrounding soil where Tilletia spores lay waiting to germinate and infect plants.

Results from 2009 tests, conducted in naturally infested soils, are pending.

Other scientists have been testing Muscodors effectiveness in biofumigating sealed cartons of apples stored at various temperatures. The results have been encouraging so far as there appears to be no adverse effect on the apples color, firmness or other characteristics.