Control of verticillium wilt in Cotinus coggygria

We analyzed the inhibition rates of eight kinds of fungicides to the pathogen of verticillium wilt of smoke tree (Cotinus coggygria) by measuring mycelium growth. Results show that four fungicides (Weijunjing, thiophanate-methyl 70% WP (wettable powder), carbendazim 50% WP and Junxianwei) have the best antifungal effects. Three fungicides, Weijunjing, carbendazim 50% WP and Junxianwei, were selected to determine the control of verticillium wilt in potted smoke tree seedlings. We found that the relative efficacy of Weijunjing was up to 74%. Based on the results, Weijunjing and carbendazim 50% WP were prepared for field trials. The results indicate that the relative efficacy of Weijunjing (300 times diluted) and carbendazim 50% WP (400 times diluted) were 66.2% and 48.9% in plot 1 and 26.4% and 31.8% in plot 2 after soil disinfection, and were 224% and 61.8% in plot 3 without soil disinfection in 2007. The relative efficacy of Weijunjing and carbendazim 50% WP were 49.6% and 45.4% in plot 2 in 2008.