BIOLOGICAL CONTROL OF FUSARIUM WILT OF MUSKMELON BY FORMULATIONS OF ASPERGILLUS NIGER

Abstract

Aspergillus niger van Tiegh. (An 27) was shown to be a promising biocontrol agent against Fusarium oxysporum Schlecht f. sp. melonis Sny. and Hans., which causes muskmelon wilt. Fruit wastes, such as carrot waste, citrus peels and pomace, mixed fruit pomace, and pineapple peels and pomace, proved to be a promising and cheap alternative source for mass multiplication of A. niger. These wastes are readily available throughout the year and can replace some of the highly priced media used for mass production of biocontrol organisms. Citrus pomace extract (20%) was found to be an excellent liquid medium for mass production. In solid fermentation, fruit wastes were superior to other media used as substrates. A short period of 10 days of incubation was sufficient for the production of 108 colony forming units (cfu) per gram of the material. The extent of control achieved by the seed coating formulation (FSC) was at par with Carbendazim. Formulation for soil application (FSO), a new contribution to the formulation science, could reduce Fusarium wilt disease by 78.31%, when applied at the rate of 8 g/kg of soil. Both FSC and FSO formulations can be stored at room temperature (14–35 °C) for more than a year.