| Abstract: | The effects of the fungal pathogen Phomopsis convolvulus Ormeno on seedling and established plant performance of Convolvulus arvensis L. were compared under both controlled and field conditions. Under a controlled environment, a granular barley formulation of the fungal inoculum that had been applied on to the soil surface of pots containing pre-germinated C. arvensis seeds resulted in above-ground biomass reductions of up to 87%. However, application of the fungus to established plants that had been cut to ground level produced biomass reductions (43%) that were nearly half of those obtained for seedlings. In a parallel field experiment conducted over two growing seasons, application of P. convolvulus resulted in dramatic above-ground biomass reductions for both seedlings and established plants. In one trial, biomass reductions of up to 100% and 98%, respectively, were obtained. C. arvensis coverage within field plots was closely correlated with above-ground biomass. Findings in this study indicated that P. convolvulus may provide effective control of C. arvensis when applied pre-emergence. |
