Citronella biomassa as a sustainable strategy for controlling the diamondback moth

Abstract

Citronella (Cymbopogon winterianus) is a plant recognized for its repellent and insecticide properties, and its essential oil (EO) has been studied for the control of different pests. In this study, the comparative effect between citronella EO and the green mass of its leaves in the control of pests in cabbage (Brassica oleracea L. var acephala) crops was investigated. After 30 days of planting commercial cabbage seedlings, the applications of treatments began, which included a control group, citronella green mass, and two concentrations of EO (0.5% and 1.0%). The applications of the treatments were repeated weekly for four weeks. For the treatment with green mass, an average of 700 g of citronella leaves cut per bed were used. The diversity of soil organisms was evaluated with pitfall traps, as well as the mass and number of leaves produced per plant in each treatment. Covering the beds with citronella leaves had a similar effect to EO in reducing damage caused by the diamondback moth (Plutella xylostella) and in reducing the average number of caterpillars per plant, when compared to the control group. In addition, the addition of citronella green mass, as well as EO, did not compromise cabbage productivity or the diversity of soil organisms. These results suggest that the use of citronella green mass may be a promising strategy for pest management, contributing to more sustainable agricultural practices and in line with the demand for pesticide-free products.