VIEW ARTICLE

Population Levels of Aspergillus flavus and the A. niger Group in Virginia Peanut Field Soils. Gary J. Griffin, Department of Plant Pathology and Physiology, Virginia Polytechnic Institute and State University, Blacksburg 24601; Kenneth H. Garren, Southern Region, Agricultural Research Service, U.S. Department of Agriculture, Tidewater Research and Continuing Education Center, Suffolk, Virginia 23437. Phytopathology 64:322-325. Accepted for publication 30 August 1973. DOI: 10.1094/Phyto-64-322.

The populations of Aspergillus flavus and the A. niger group were determined in the fruiting zone of Virginia peanut field soils during the middle of the fruit-forming period with a selective medium (M3S1B) containing NaCl and 2,6-dichloro-4-nitroaniline. The mean populations of A. flavus were much lower than reported previously for peanut field soils. In five fields sampled in 1971, and in six fields sampled in 1972, A. flavus populations ranged from 0.8 to 12.8, and from 0.5 to 57.3 propagules per g soil, respectively. A. niger group populations were mostly low also, and there was little relation between A. flavus and the A. niger-group populations or between A. flavus populations and soil properties. Population determinations of soil from two fields for three years suggested that planting peanuts did not result in an increased A. flavus population. A. flavus may be able to colonize peanut fruits from low inoculum density levels.