[Effect of drying and temperature on the sporulation of Pandora delphacis mycelia gelatinized].

The entomophthoraceous fungus, Pandora delphacis, is a microbial agent highly potential for control of sucking-type insects. In this study, effort was made of gelatinizing the mycelia of the isolate F95129 from submerged culture using polyacrylamide-starch gel pwder and sodium alginate. The resulting film-like gel of the mycelia sporulated very well, indicating that the materials used for gelatinization of the mycelia was biologically compatible with P. delphacis. Then, the gelatinized mycelia were slowly dried in silica chamber at 4, 14, and 24 degrees C, respectively. After 35-day drying and storage in the chamber, however, a 22.7%-92.8% decrease of sporulation capacity occurred in the film-like gels, which then had different water content. The nutrient-supplemented polyacrylamide-starch gel stored at 14 degrees C with water content of 6.1%-7.4% was best for largely decreasing the loss of sporulation capacity among the combinations of gel, nutrition, water content and temperature. The results indicate that it could be possible to choose a desirable gel for longer biological activity of gelatinized P. delphacis mycelia.