Studies were carried out to elucidate the parental (vertical) transmission of Nosema marucae Odindo and Jura, in infected females of Chilo partellus Swinhoe. Results indicated that only infected females of C. partellus could pass infection to the offspring. Infection also lowered both the total number of eggs laid per female and egg hatchability- Some adults which developed from the sublethally infected fifth instar larvae of C. partellus had deformed wings while some pharate adults failed to free themselves from the pupal cases. The significance of these deformities to the ecological survival of C. partellus is discussed.
