International Science Community Association International Research Journal of Biological Sciences 2278-3202 12 2 2023 08 10 Preliminary studies on formulation of Neem oil based micro emulsion and insecticidal effect on eggplant Mealy bugs 34 41 EN Menon Karthika S. 1 Department of Botany, Vimala College (Autonomous), Thrissur, Kerala, India P.M. Dhrisya 2 Department of Botany, Vimala College (Autonomous), Thrissur, Kerala, India Mshelmbula Barka P. 1 Department of Plant Science and Biotechnology, Federal University of Lafia, PMB 146, Lafia, Nigeria Anoliefo Geoffrey O. 2 Environmental Biotechnology and Sustainability Research Group, Dept. of Plant Biology and Biotechnology, University of Benin, Benin City, Nigeria Ikhajiagbe Beckley 3 Applied Environmental Biosciences and Public Health Research Group, University of Benin, Benin City, Nigeria and Department of Microbiology, University of Benin, Benin City, Nigeria Edegbai Boniface O. 4 Environmental Biotechnology and Sustainability Research Group, Dept. of Plant Biology and Biotechnology, University of Benin, Benin City, Nigeria Goodlife Eugenia Ebene 1 Department of Plant Science and Biotechnology, Rivers State University, PMB 5080, Port Harcourt, Rivers State, Nigeria Jaja Emylia T. 2 Department of Plant Science and Biotechnology, Rivers State University, PMB 5080, Port Harcourt, Rivers State, Nigeria Wilson Victoria 3 Department of Plant Science and Biotechnology, Rivers State University, PMB 5080, Port Harcourt, Rivers State, Nigeria Remi Osanyinlusi 1 Department of Science laboratory technology (Chemistry Unit), Rufus Giwa Polytechnic Owo, Ondo State, Nigeria K.V Ajayan 1 Department of Post graduate Studies and Research in Botany, Karnataka State Akkamahadevi Women’s University, Vijayapura, Karnataka, India Awati Preeti 2 Department of Post graduate Studies and Research in Botany, Karnataka State Akkamahadevi Women’s University, Vijayapura, Karnataka, India Kalyani Savita 3 Department of Post graduate Studies and Research in Botany, Karnataka State Akkamahadevi Women’s University, Vijayapura, Karnataka, India Karekal Suma 4 Department of Post graduate Studies and Research in Botany, Karnataka State Akkamahadevi Women’s University, Vijayapura, Karnataka, India > Research Paper 2023 4 5 2023 08 10 Neem oil based microemulsions were prepared by two surfactants Tween 20 and DMSO (Dimethyl sulphoxide) for preliminary on eggplant mealybugs on Brinjal eggplant (Solanum melogenic) family Solanaceae. The microemulsions has three phases Oil phases, Surfactant phase and aqueous phases. Six separate mixtures of Tween 20 and Neem oil in various weight ratios-1:0, 1:1, 2:2, 3:3, 4:4, and 5:5-were taken and diluted to one litre. The physical factors like pH, Electric conductivity, Transparency, emulsion size determination by light microscope. Pesticide efficiencies were tested in field under greenhouse conditions. Tween 20 based micro emulsions has highest efficiency in first, second and third spray intervals compared to DMSO based micro emulsions on eggplant mealybugs. pH ranges of Tween 20 freshly prepared micro emulsions from 3.76 -5.88; in Electric conductivity 58-170 and one month old emulsions has 3.21 to 6.03; in Electric conductivity 58-170; in Electric conductivity 50-200 whereas DMS based Neem micro emulsions pH ranges from 4.07-6.02 freshly prepared; in Electric conductivity 51-128 and one month old emulsions ranges 5.22-6.02; in Electric conductivity 51-65. Transmission of freshly prepared of Tween 20 microemulsions from 0.27-36.1and one month old emulsions has 0.1 -60.57 whereas Transmission of freshly prepared of DMSO based Neem microemulsions ranges from 0.1 to 60.1 and one month old emulsions ranges 0.1-30.63. Preliminary studies indicated that Tween 20 based micro emulsion of Neem oil has been better pesticide efficiency compared to DMSO based micro emulsion of Neem oil. Copyright@ International Science Community Association