Survival of Colletotrichum gloeosporioides f. sp. aeschynomene in Rice Irrigation Water and Soil. D. O. TeBeest, Assistant Professor, Department of Plant Pathology, University of Arkansas, Fayetteville 72701. Plant Dis. 66:469-472. Accepted for publication 31 July 1981. Copyright 1982 American Phytopathological Society. DOI: 10.1094/PD-66-469.

Survival of spores and mycelium of Colletotrichum gloeosporioides, incitant of northern jointvetch anthracnose, was studied in host debris, rice irrigation water, and soil under laboratory and field conditions. The fungus was not recovered from soil collected from artificially infested field plots after 9 wk and was only occasionally reisolated from host debris buried in soil for more than 2 wk. Recovery was successful from host debris left above the soil on plants collected 7 mo after field inoculation. Under laboratory conditions, the fungus was recovered from sterile water but not from rice irrigation water 180 days after infestation with spores. Populations of C. gloeosporioides introduced into field soil stored in the laboratory declined to less than 1% of the original population within 4 wk but increased 8 to 80 times in the sterile soil control in the same time period. Sclerotia or sexual fruiting bodies of the fungus have not been found in culture or in infested plant debris.

Keyword(s): biological control, mycoherbicide, pest management.