Population Dynamics and New Record of Larval Parasitoids, Senometopia Sp. and Winthemia sumatrensis (Townsend) (Diptera: Tachinidae) on Banana Skipper, Erionota torus Evans (Lepidoptera: Hesperiidae) from South Karnataka

摘要

Field study was conducted for two years (2014-16) to know the population dynamics of banana skipper, Erionota torus Evans (Lepidoptera: Hesperiidae) and its tachinid parasitoids, Senometopia sp., and Winthemia sumatrensis . The pooled data over the two years indicated that the skipper plant infestation ranged from 6.66 to 84.25 per cent and incidence started during the first fortnight of August (8.34 per cent incidence) when the crop was at broadleaf follower stage, and a gradual increase in the infestation level of skipper was observed with a peak activity (84.25 per cent incidence) during first fort night of January (Pre flowering period) and also extended to the flowering period (February to March). The pooled data over the years indicated the maximum incidence was recorded during pre flowering period with a mean infestation of 75.02 per cent followed by flowering period (45.67 per cent), broad leaf followers (29.58 per cent) and bunch period (1.66 per cent). Two tachinid parasitoids Senometopia sp., and W. sumatrensis were encountered during our two years study period. The larval parasitoids activity initiated from second fortnight of September (0.62 per cent) and reached its maximum population during second fortnight of November (7.25 per cent) and later parasitoid activity gradually declined till second fortnight of January (0.62 per cent). The maximum activity was noticed during pre flowering period with a mean of 3.27 per cent parasitization by Senometopia sp., and W. sumatrensis .