A novel method for promoting conidial production by a nematophagous fungus, Pochonia chlamydosporia AS6.8

A novel method was described for promoting conidial production of nematophagous fungus, Pochonia chlamydosporia AS6.8, by hydrogen peroxide (H2O2) treatment and two-stage cultivation. The fungi were first grown on potato dextrose agar plates to encourage vegetative growth, after briefly treating with 90 mM concentrations of H2O2, and then were transferred to water agar (WA) plates for sporulation. Sporulation of the P. chlamydosporia AS6.8 was significantly enhanced (as much as 15 times) using this method. Enhancement of sporulation by H2O2 (oxidative stress) and by transfer to WA (low-nutrient stress) was not synergistic. In order to make sure if the H2O2 had enhancing effect on other nematophagous fungi, we also evaluated the effect of H2O2 on sporulation of Arthrobotrys oligospora CBS 115.81 and Dactylellina cionopaga CBS 113355 besides P. chlamydosporia. And the result showed that 90 mM concentrations of H2O2 had enhancing effect on sporulation of all of the three isolates.