Effects of fungicides for against smut and Pokkah boeng disease in sugarcane under laboratory conditions

Abstract

Sugarcane smut disease, caused by Sporisorium scitamineum and Pokkah boeng disease in sugarcane is caused by the fungus Fusarium moniliforme are a serious disease that causes severe damage to the sugarcane industry, particularly in ratoon crops. At present, this disease is a major constraint to sugarcane cultivation worldwide. Although chemical fungicides have been recommended for its management, the disease still outbreaks in sugarcane fields, their efficacy varies. This study aimed to evaluate the effectiveness of eight fungicides for controlling sugarcane smut. The fungicide experiment included difenoconazole + propiconazole, propiconazole + azoxystrobin, azoxystrobin, dimethomorph, tebuconazole + fluopyram, kasugamycin hydrochloride hydrate + tricyclazole, prochloraz, and dipotassium phosphite. The poisoned food technique on PDA medium was used to assess the inhibitory effects against S. scitamineum under laboratory conditions. The percentage of mycelial growth inhibition was calculated. Results indicated that difenoconazole + propiconazole, propiconazole + azoxystrobin, azoxystrobin, and tebuconazole + fluopyram, at a rate of 25 g per 20 L of water, achieved 100% inhibition of S. scitamineum growth. The results indicated that difenoconazole + propiconazole, tebuconazole + fluopyram, kazugamycin hydrochloride hydrate + tricyclazole, prochloraz, mancozeb and copper hydroxide completely inhibited the growth of F. moniliforme at 100% inhibition. These findings provide preliminary recommendations for the effective use of fungicides to manage sugarcane smut and Pokkah boeng to minimize the risk of fungicide resistance. The most effective fungicides will be further evaluated under greenhouse conditions for disease control.