Seasonal parasitization of Cotesia flavipes in Sugarcane against top borer, Scirpophaga excerptalis (Walker)

The per cent incidence of top borer was varied from 2.7 to maximum 11.3% in the month of June, when corresponding weather parameters viz., maximum, minimum temperatures, relative humidity (%) at 07 hrs and 14 hrs and rainfall (mm) were 36.2°C, 26.3°C, 82.9%, 58.7% and 46.6 mm, respectively. Correlation was found that temperature, (maximum & minimum) showed highly significant positive correlation with % incidence of top borer. While relative humidity recorded (07 hrs & 14 hrs) nonsignificant correlation but statistically was found as positive at 14 hrs and negative relationship with 07 hrs. However, rainfall exhibited positive and found statistically was non-significant. Parasitization of Cotesisa flavipes ranged between 1.4 to 8.3% during May to November with its highest population (8.3%) was recorded in month of September during crop season 2014–15 when corresponding weather parameters viz., maximum, minimum temperatures, relative humidity (%) at 07 hrs and 14 hrs and rainfall (mm) were 32.50°C, 25.75°C, 90.70%, 70.80% and 64.7 mm, respectively. The minimum temperature, relative humidity 14 hrs and rainfall showed positive significance relation with parasitization of Cotesia flavipes. The parasitization of C. flavipes ranged between 3.1 to 15.9% during May to November with its highest population (15.9%) was recorded in month of September and correlation pattern same as cropping season (2014–15).