Management of black mold rot of onion

Black mold rot are the most destructive diseases of onion in storage and in the field. The present study was carried out to isolate the fungus assocaited with black mold rot of onion and to control dosease with seven different systemic and non-systemic fungicides. On the basis of morphological chracteristics, Aspergillus niger Van Tieghem was found to be associated with black mold rot of onion. It was observed that all the fungicides caused significant reduction in the mycelial growth, lesion diameter, spore germination and rot severity. Amongst systemic fungicides, carbendazim brought about highest reduction followed by hexaconozole, bitertanol and myclobutanil, respectively. Amongst non-systemic fungicides, the mancozeb was found the most effective followed by captan and zineb, respectively. The higher concentrations (1000 ppm and 2000 ppm) of all the fungicides proved more effective than lower concentrations (125 ppm and 500 ppm). The current study showed effective utilization of hexaconozole and mancozeb for the control of black rot of onion caused by A. niger.