INOCULUM PRODUCTION OF PHAEORAMULARIA, A POTENTIAL MYCOHERBICIDE FOR CROFTON WEED

Factors likely to influence the production of Phaeoramularia sp. as a mycoherbicide to control crofton weed (Ageratina adenophora) were inve stigated. The fungus grew best on potato-dextrose agar (PDA) and carna tion leaf-piece agar and sporulated best on PDA and a decoction agar m ade from A. adenophora. The fungus grew and sporulated best at 20 and 25 degrees C and at water potentials between -0.4 and -1.5 MPa. For sm all scale production of conidia of the fungus a combination of submerg ed and solid culture with the fungus grown in liquid culture resulted in the greatest number of conidia. Comparative studies showed that myc elium was as pathogenic as conidia and that the former may have potent ial for further development as a mycoherbicide.