Natural parasitism of agromyzid leafminer, Chromatomyia horticola (Goureau) (Diptera: Agromyzidae) on field pea

The leafminer, Chromatomyia horticola (Goureau), (Diptera: Agromyzidae) which infests field pea, is exposed to various parasitoids. Observations were made on the seasonal incidence and parasitization of agromyzid leafminer, C.horticola in Pea crop fields at Pantnagar, Uttarakhand (India) during cropping season of the year 2009 to 2010, 2010 to 2011. Leafminer infested leaves were randomly collected from field and maintained at room temperature (25 to 30°C). Number of emerged adult leafminers and parasitoids were recorded to calculate weekly percent parasitisation. The peak period of parasitization in both years was during 9th standard week constituted 71.69 and 68.87% of parasitization, respectively. Three hymenopteran parasitoids were recordedviz., two eulophids (Diglyphus horticola Khan, Diglyphus sp.) and one braconid (Opius sp.). Influence of environmental factors viz., temperature, relative humidity, and rainfall on weekly percent parasitization was non-significant.   Key words: Leafminers, agromyzidae, hymenoptera, parasitoids, eulophidae, Diglyphus horticola Khan,Opius sp.