PREVENTION OF FUNGAL DISEASES IN TRANSGENIC, BIALAPHOS-RESISTANT AND GLUFOSINATE-RESISTANT CREEPING BENTGRASS (AGROSTIS-PALUSTRIS)

The antifungal activity of the herbicides bialaphos and glufosinate, t he active moiety of bialaphos, was assessed. Bialaphos showed a higher level of in vitro antifungal activity against Rhizoctonia solani, Scl erotinia homoeocarpa, and Pythium aphanidermatum than glufosinate. Glu fosinate suppressed the mycelial growth of R. solani and S. homoeocarp a, but it had no inhibitory effect on P. aphanidermatum up to the high est concentration in our testing regimes. Various concentrations of bi alaphos solutions were applied to transgenic, bialaphos- and glufosina te-resistant creeping bentgrass inoculated with fungal pathogens. Bial aphos applications were able to significantly reduce symptomatic infec tion by R. solani and S. homoeocarpa on transgenic plants. Bialaphos s ignificantly inhibited P. aphanidermatum, but not to the same degree t hat R. solani and S. homoeocarpa were inhibited. These results indicat e that bialaphos may provide a means for the simultaneous control of w eeds and fungal pathogens in turf areas with transgenic, bialaphos-res istant creeping bentgrass.