Vertical Transmission of a Nosema sp. (Microsporida: Nosematidae) Infecting a Grasshopper, Chorthippus curtipennis (Orthoptera: Acrididae)

Vertical transmission studies of a Nosema sp. infecting a grasshopper, Chorthippus curtipennis (Harris), were conducted in the laboratory. Mated pairs of field-collected grasshoppers were allowed to oviposit, and the adults and progeny were subsequently examined for infection. Infection status of the parents had no effect on fecundity. A preliminary analysis of observed differences in percentage hatch was also not significant, but further analysis suggested that there were differences between mated pairs. The analysis suggested that some of the differences in hatch rate were caused by infection of the female when mated pairs were subsequently classified as having a high or low hatch rate. Vertical transmission was maternally mediated, with >70% of the progeny infected at5 d after hatch.