Yield of conidia and germination of different isolates ofMetarhizium anisopliae (Metsch) Sorok. (Ascomycota: Clavicipitaceae) grown on rice

Abstract

In order to determine the production and viability of different isolates of Metarhizium anisopliae, 100 g of pre-cooked rice were placed in 35 cm long and 22 cm wide polypropylene bags, being immediately autoclaved at 120°C for 25 minutes. After cooling down, the rice was inoculated with 1 mL of a suspension containing 1,0 x 109 conidia/mL, packed in an incubator at 25 ± 1°C, 70 ± 10% RH and 12 hours of photophase. Plastic bags containing rice + fungus were incubated for 10 days. After this period, rice + fungus was packed in plastic trays to promote fungal conidiogenesis, within the climatic chamber at 2 5 ±1°C, 70 ± 10% RH and 12 hours of photophase. The trays were stacked for four days, being crossed for another four days. The IBCB 425 isolate was the most produced conidia on rice with 1.82 x 109 conidia/g of pre-cooked rice by the tray method. Regarding the viability of the isolates, IBCB 425 also showed a higher germination of conidia, with 94.84%.