OCCURRENCE OF FUNGUS ENTOMOPHTHORA GRYLLI FRESENIUS ON LOCUSTS AND GRASSHOPPERS IN THAILAND

The mode of growth of Entomophthora grylli and its effect on locusts and grasshoppers are briefly described. In recent years infestations of several species of Acridoidea have occurred in Thailand, notably of Patanga succincta. In two consecutive years Entomophthora grylli caused extremely high mortality among immature adult Patanga during periods of particularly heavy and prolonged rainfall, and was probably the most important mortality factor. Minor infections also occurred at other times of the year following periods of less heavy and less prolonged rainfall. Entomophthora infections are recorded on 10 species of locust and grasshopper. It is concluded that the usefulness of Entomophthora grylli as an agent in biological control is unlikely to be improved upon unless a strain which requires drier and cooler conditions for growth is produced artificially. © 1968.