Bioefficacy of plant extracts against nymphs of Phenacoccus Solenopsis Tinsley on BT Cotton Sengani S.H.1, Vekaria M.V. Department of Agricultural Entomology, C.P. College of Agriculture, Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, 385506, E-mail: senganisumit26@gmail.com 1Present Address: Jitpurkampa, P.O. Vadagam, Taluk Dhansura, District Aravali, 383307 Online published on 3 November, 2015. Abstract Bioefficacy of botanical insecticides evaluated under laboratory conditions on Bt cotton revealed that tobacco leaf extract 5% was the best treatment and it gave 73.45% mortality of the first instar nymph of mealy bug Phenacoccus solenopsis within 48 hours. The datura leaf extract 5% (73.45%), NSKE 5% (69.96%) and ardusa leaf extract 5% (63.37%), respectively were found highly effective against the first instar within 72 hours. In case of the third instar, the tobacco leaf extract 5% was observed with 79.97% mortality within 72 hours. The treatments of NSKE 5% (66.69%) and datura leaf extract 5% (66.72%) were found highly effective against the third instar after 72 hours of application. Top Keywords Plant leaf extracts, Mealy bug, first, second and third instar, tobacco leaf extract. Top |