Preparation of nanoemulsion Neem extract for biopesticide of Nilaparvata Lugens, Brown Planthopper

Abstract

Extracts of neem (Azadirachta indica A. Juss) are used nowadays for many purposes including management of agricultural insect pests. The effects of neem extract on mortality, survival and weight of the brown planthopper (BPH), Nilaparvata lugens were investigated. BPH is one of the most serious pests in paddy fields in Asia that causes physiological damage to rice crops. The use of neem extract in free form as biopesticide is not practical anymore since the compound is unstable under harsh environment. Therefore, the nanoemulsion of neem extract was formulated as biopesticide for the agricultural sectors. The nanoemulsion was made up from neem extract, olive oil as carrier oil and Tween-80 as surfactant. The method that used was ultrasonic emulsification method. The nanoemulsion preparation undergoes optimization by using Response Surface Methodology which is Central Composite Design to get the best formulation as biopesticide against BPH. The investigated parameters were encapsulation efficiency, Fourier Transform Infrared analysis and toxicity test. Finally, the DOE study shows that the optimum encapsulation efficiency was 87.7 % when the volume of oil 4.00 ml, sonication time 10.00 min and volume of alginate solution is 2.00 ml. For the toxicity test, the mortality of BPH was 100%.