Age-Specific Response of Atteva sciodoxa Meyrick (Lepidoptera: Yponomeutidae) to Beauveria bassiana (Bals.)

Beauveria bassiana (Bals.) was bio-assayed against three larval instars of Atteva sciodoxa under laboratory conditions of 27±2ºC, 75% RH and 12:12 h photoperiod. Instar 3rd responded with100% mortality at 5x10^7 conidia ml^-1, while same level of mortality was recorded in 5th instar at 1x10^8 conidia ml^-1. Instar 5 also showed the lowest mortality (33.3%) at 1x10^6 conidia ml^-1. Median effective concentration (EC50) ranged between 9.87x10^5 and 21.30x10^5 conidia ml^-1 for 3rd to 5th instars. Median effective time (ET50) ranged between 3.3 days and 8.2 days for different tested concentrations. A significant (p 0.05) 2nd degree correlation between temperature and B. bassiana infectivity was analysed. Beauveria bassiana infection was in range of 27-30ºC. Based on these findings, it is concluded that B. bassiana has promising potential as microbial control agent against A. sciodoxa and should be exploited under field conditions.