Determination of Optimal Culture Medium Conditions for Mass Production of Beauveria bassiana Clone EF 46

Abstract

The issue of food safety has become a major concern due to the use of chemical pesticides, which have deleterious effects on human health, the environment and biodiversity. Biological pest control, which uses entomopathogenic agents, is an alternative that is more respectful of the health of living beings and the environment. This study aimed to determine the optimal culture medium parameters for the indigenous strain Beauveria bassiana clone EF 46, aiming to facilitate the development of biopesticides. Potato Dextrose Agar (PDA) medium was used to evaluate the influence of physical (temperature, photoperiod, pH) and nutritional (carbon and nitrogen sources) parameters on the sporulation of B. bassiana. Concurrently, rice husk supplemented with different types of starch flours was used to determine the best substrate for solid-state fermentation. This study revealed that the optimal physical parameters for sporulation were: a temperature of 25 °C, an alkaline medium with a pH of 9, and a 12h: 12h light/dark photoperiod. Regarding nutritional parameters, fulvic acid and baker's yeast were identified as the best carbon and nitrogen sources, respectively. Concerning the culture substrate for solid-state fermentation, yellow corn flour proved to be the best supplement for rice husk.