Effect of low temperature storage on the efficiency of three species of trichogrammatids

摘要

The effect of low temperature (4 ± 0.5" C) and refrigerator storage on three trichogrammatids, viz Trichogramma chilonis Ishii, T. pretiosum Riley and T. brasiliense Ashmead was studied under laboratory conditions. T. chilonis and T. pretiosum can bestored for 20 days whereas T, brasiliense for 10 days without adversely affecting their emergence and parasitisation efficiency taking 60 per cent emergence and 60 per cent parasitism as standard. The emergence in T. brasiliense reached zero per cent after 34 days of storage whereas 20.3 per cent was recorded in T. chilonis and 15.7 per cent in T. pretiosum after 60 days of storage. T. chilonis showed the highest emergence and parasitization efficiency followed by T. pretiosum and T. brasiliense.