Large scale production of New Zealand strains of Beauveria and Metarhizium

Beauveria and Metarhizium spp. are currently under development around the world as biocontrol agents for a variety of pest insects. Use of these fungi in practical biocontrol programmes will require production of large amounts of inoculum. Although production techniques on solid substrates have been developed overseas, the production characteristics of New Zealand strains were unknown. The effects of solid media (rice, wheat and barley) with additives (glucose and yeast extract), temperature and length of incubation on conidial production were investigated. Maximum conidial yields achieved were 4.38 x 10 9 conidia/g rice for B. bassiana, 3.02 x 10 9 conidia/g dry substrate for B. brongniartii, and 1.42 x 10 9 conidia/g dry substrate for M. anisopliae. In all cases, maximum yield was achieved when fungi were grown on rice for 3 weeks at 23C, under natural daylight.