Xanthopimpla punctata Fabricius

Xanthopimpla punctata is a solitary, polyphagous, pupal parasitoid. It is considered as a significant biotic agent of Opisina in Tamil Nadu and Kerala during July to December with a peak period of activity during September-October. The parasitoid is particularly abundant in localized tracts close to the sea such as back waters or other water ways or in irrigated coconut plantations (areas with high pest population).

The parasitoid can be reared using glass chimney or bottle jars. Five to six mated females and two to three male parasitoids are released in a glass bottle. For adult feeding honey is provided as small droplets on a piece of wax-coated paper. The mouth of the jar is secured with a piece of mosquito net cloth with rubber bands. Over the net cloth pupae of Anadevidia (Plusia) peponis or Opisina arenosella are placed. The pupae are held tight to the mosquito net cloth cover of bottle with a piece of muslin cloth and rubber bands. The glass bottle is kept horizontally. Host pupae are offered 4-5 days after mating of the parasitoid. In case only Opisina arenosella pupae are used, the pupae with silken galleries are cut along with coconut leafbits in tact, and are placed between the nylon mesh and the muslin cloth coverings of the jar containing mated parasitoids. Disorganization of host tissues takes place due to the repeated thrusts with the ovipositor and its rotary movement. The adult parasitoid feeds on the haemolymph that exudes through the oviposition punctures made. Depending on the activity of the parasitoids the exposure time for parasitisation can be 1-3 hours. The parasitised pupae show clear oviposition punctures.

Parasitised pupae are transferred to separate jars and kept for emergence of adult parasitoids. Moistened cotton rolls are provided in the jars to maintain adequate relative humidity, particularly during dry summer season.

Egg to adult stages of X. punctata are completed in 10-20 days (egg period one day; larval period 4-10 days; pupal period 5-10 days) under a temperature range of 22-30°C and 45-80% RH. Normally, the male parasitoids emerge one day earlier than the females. The females live for one to five months.