In vitro Inhibitory Effects of 11 Fungicides on Mycelial Growth of Sugarcane Red Rot Pathogen

Red rot caused by Colletotrichum falcatum Went is the most devastating problem of sugarcane(Sacchrum officinarium L.) and causes serious yield losses under favorable environmental conditions. In order to understand the pathogen sensitivity to fungicides, and 11 fungicides were tested in vitro for their effectiveness to inhibit to four isolates of C. falcatum. The results indicated that different fungicides exhibited diverse toxicities, and the most effective in vitro proved to be the fungicides containing tebuconazole, propiconazole, prochloraz, difenoconazole and carbendazim. Their EC50 and EC95values for inhibition of the isolates ranged from 0.227 μg / m L to 0.818 μg/m L and 1.416 μg/m L to 11.339 μg/m L,respectively. The in vitro sensitivity of C. falcatum to 11 fungicides was also examined. The results showed that the b values from carbendazim were the highest among the 11 fungicides with respect to different isolates. These results indicate that the sugarcane red rot pathogen is more sensitive to carbendazim than other fungicides tested.