Bio-efficacy of new insecticidal molecules against insect-pests of cotton

Field evaluation of new insecticidal molecules was conducted against sucking pests and bollworms of cotton. The new molecules tested were methomyl (Lannate 40 SP), thiodicarb (Larvin 75 WP), triazophos (Hostathion 40 EC), lamda cyhalothrin (Karate 40 EC), profenofos + cypermethrin (Polytrin-C 44 EC), triazophos + deltamethrin (Spark 36 EC), indaxocarb (Auvant 14.5 SP), chlorpyriphos + cypermethrin (Chop 55 EC), endosulfan (Endocel 35 EC) and dimethoate (Rogor 30 EC). Methomyl recorded the lowest (2.00) aphid population which was on par with thiodicarb (2.69) followed by other insecticdes. Thiodicarb recorded the lowest (4.17) thrips population followed by indoxacarb and other treatments. The insecticidal treatment chlorpyriphos + cypermethrin recorded minimum (1.2 per plant) number of larvae and was significantly superior over triazophos + deltamethrin (4.2 larvae per plant) but on par with rest of the treatments in three days after first spray during first season. Methomyl recorded the lowest (0.87) bollworm population and was significantly superior over profenofos + cypermethrin (3.47), endosulfan (4.00) and control (13.20), but was on par with rest of the treatments during three days after fourth spray. The cost benefit ratio was maximum in methomyl (1:2.68) followed by chlorpyriphos + cypermethrin, profenofos + cypermethrin and indoxacarb.