Aphids are highly damaging insect pest of mustard crop that causes direct and indirect losses in many growing areas of Pakistan. In addition to insecticides, biocontrol agents, especially Coccinella septempunctata, play a significant role in managing aphid population. The consistent use of insecticides may directly and indirectly (through poisoned aphid) have significant effect on the Coccinella septempunctata. Keeping in view the importance the effect of new chemistry insecticides directly and through poisoned mustard aphid on development of Coccinella septempunctata were assessed in lab conditions. Under laboratory conditions, this experiment was conducted by using CRD layout with four replications of each treatment. Four different concentrations of insecticides (Flonicamid and Spirotetramat) were applied by direct application of pesticides on adults of C. septempunctata and indirectly through by feeding poisoned aphid to C. septempunctata. The mortality and consumption rate of poisoned aphids were counted after 24, 48 and 74 h of study period. Results showed that in case of direct application, the maximum mortality were recorded 58.75±0.25 and 51.50±0.28% after 72 h of treatment of Spirotetramat and Flonicamid @ 1500 and 150 ppm, respectively. In case of indirect application (through poisoned aphids), the maximum mean mortality percentage was noticed 36.00±1.2% with lowest consumption 70.66±2.62% after 72 h of study period by the treatment of Flonicamid @ 150 ppm conc. Similarly, the maximum mean mortality percentage 43.33±0.72% was noticed with lowest consumption rate of 49.33±2.65% after 72 h of study period by the application of Spitotetramat @ 1500 ppm. The Spirotetramat (50 EC) is considered more toxic than Flonicamid (50 wg). Furthermore, results showed that as consumption rate increases mortality decreases and consumption decreases mortality increases. In some cases, the feeding behavior remains asymptomatic. This study provides insight into the ecological consequences of using new chemistry insecticides and their implications for IPM strategies in agriculture.

Key words: aphids, Coccinella septempunctata, Flonicamid, insecticides, natural enemies, Spitotetramat