Towards a development of novel bioinsecticides for organic control of Planococcus ficus in vineyards

Abstract

The mealybug species, Planococcus ficus Signoret (Hemiptera: Pseudococcidae) is a pest thatmainly affects grapevine plantations (Vitis vinifera L.), causing huge economic losses in theworld. The numerous problems caused by the use of synthetic pesticides on the environment andhuman health have motivated the development and implementation of natural pesticides. Theobjective of this work was to develop effective and efficient contact bioinsecticide formulationsfor the control of P. ficus in vineyards. Anti-mealybug formulations were developed using (R)-(+)-pulegone as an active principle, TWEEN® 20 and soy lecithin powder as surfactants, andlimonene and diatomaceous earth (DE) as insect waxy layer reducers. The insecticidal propertiesof formulations against vine mealybugs and their grapevine leaf phytotoxicity were evaluated inlaboratory conditions. Pulegone+DE+Lecithin and Pulegone+Limonene+DE+Lecithinformulations showed the highest mortality rates of P. ficus (more than70% mortality) at 24 h and48 h of treatment. This high mortality is probably due to an interaction between pulegone, DEand soy lecithin that allows more molecular mobility and increases the efficiency of the activesubstance, making it enter and act on the insect. In conclusion, the Pulegone+DE+Lecithin andPulegone+Limonene+DE+Lecithin formulations can be an efficient tool for the organic controlof P. ficus in vineyards.