STABILITY OF COLLETOTRICHUM-TRUNCATUM IN CULTURE INFLUENCES MYCOHERBICIDE EFFICACY

Colletotrichum truncatum, a potential mycoherbicide for control of hem p sesbania, formed spontaneous variants on agar medium. The predominan t variant produced more spores than the wild type on potato dextrose a gar but the wild type produced more spores on Czapek-Dox agar. Spore y ield of both types was greatly reduced on Czapek-Dox. In liquid cultur e, the variant spontaneously arose and gradually displaced the wild ty pe. Although the variant produced more spores in liquid culture, it ha d reduced virulence. Displacement of wild type strains by similar vari ants in liquid fermentation may constrain production of this mycoherbi cide and should be considered during the preparation of C. truncatum i nocula.