PERVASIVENESS OF HYMENOPTERANS' PARASITOIDS ON PLUTELLA XYLOSTELLA (L.) IN CABBAGE FIELDS OF TAXILA AND MANSEHRA AREAS

Studies were conducted in the farmers' fields to determine parasitoids species of plutellaxylostella in cabbage crop during october - november and march - may in 2011-12 in mansehra and taxila areas. the impact of the prevalent parasitoids species was quantified against different stages of the dbm to categorize their importance. a total of four primary parasitoids species of wasps were recorded and identified in both localities. among these, two species of larval parasitoid, diadegma insulare cresson (ichneumonidae) and cotesia plutellae kurd. (braconidae) were solitary parasitoids. third one was oomyzus sokolowskii kurd. (eulophidae), a gregarious parasitoid which attacked both larval and pupal stages of the host and 4th one, the diadromus collaris gravenhorst (ichneumonidae) was recorded as a pupal parasitoid. the parasitisation in diamondback moth larvae by various larval, pupal and larval-pupal parasitoids was recorded in 13 localities of the study area. during the farmers field visits on weekly basis, 35 and 25 cabbage fields were sampled from the taxila and mansehra areas, respectively. the average distance between the locations understudy was about 2-4 km. immature stages of dbm viz., eggs, different larval instars, pre-pupae and pupae were collected from the cabbage fields on weekly interval basis. collections were only made from the cabbage fields which were not sprayed at least during previous 10 days. maximum dbm parasitism (%) recorded was 39.68% by d. insulare, 4% by c. plutellae, 24.24% by o. sokolowskii and 27.20% by d. collaris.