Population dynamics and parasitoids activities of spotted pod borer (Maruca vitrata) in pigeonpea (Cajanus cajan)

Studies were carried out on population dynamics and parasitoids activities of legume pod borer, Maruca vitrata (Geyer) in unprotected pigeonpea crop during kharif seasons of 2013–14 and 2014–15 at Agricultural Research Station, Chitapur (Karnataka), India. The observations revealed that the infestation of pest started with the onset of flower bud and flowers on crop (in 2^nd fort night of September) and thereafter incidence was increased and thus attained peak during II fortnight of October to first fortnight of November (14.33 to 22.00 larvae per 10 plants) in both the locations. Afterwards it declined to moderate level (9.00 to 14.66 larvae per 10 plants) during II fortnight of November. However, again 2^nd peak incidence of 15.00 to 19.33 larvae per 10 plants noticed during II fortnight of December in both the locations. Again the pest incidence drastically decreased after II fortnight of December. Per cent larval and pupal parasitization of M. vitrata collected from field and observed in laboratory recorded thathighest 8.33±2.88 and 6.00±2.64% parasitization of larval and pupal stage by Goniozus spp was observed, respectively. Whereas, parasitization by Bassus relativus was 4.66 ±1.52 and 3.66 ±1.52% at larval and pupal stage of pest, respectively.