OBSERVATION ON THE HOST PARASITOID INTERACTION BETWEEN PERIPLANETA-AMERICANA, THE AMERICAN COCKROACH AND TETRASTICHUS-HAGENOWII, AN OOTHECAL PARASITOID

Investigations were carried out on the host parasitoid interaction bet ween Periplaneta americana, the American cockroach and Tetrastichus ha genowii, an oothecal parasitoid. This gregarious female parasitoid inf ected and or oviposited in only one host and caused 100% mortality of the infected host. However, increase in parasitoid density decreased t he progeny production and influenced the sex ratio. The progenies prod uced were male biased. When host preference was tested by offering oot hecae of different species of cockroaches, T. hagenowii showed a predi lection towards the oothecae of P. americana, suggesting its host spec ificity.