Application of Lantana camara L. leaf extracts and essential oils for increasing yield and improving pest management in the production of tomato (Solanum lycopersicum L.) cultivar VF

Abstract

Tomato (Solanum lycopersicum L.) is the most commonly consumed vegetable in Nigeria, and synthetic pesticides are frequently used to protect tomatoes against pests and diseases. However, the environment and human health are negatively impacted by their use, prompting consideration of alternative, environmentally safe treatments. Lantana camara L. (commonly known as sage, family Verbenaceae), a commonly occurring plant, has shown promise as a natural alternative for controlling tomato pests and may serve as an eco-friendly substitute for synthetic pesticides. Therefore, the potential of extracts of L. camara and essential oils (EOs) for the production and protection of the tomato variety “Roma VF” was studied under field conditions in Ibadan, Nigeria. Fresh L. camara leaves were collected from plants growing on the University of Ibadan campus, Oyo State and identified at the Herbarium section, Department of Botany, University of Ibadan (UIH 23103). The leaves were air-dried, pulverized and subjected to hydrodistillation for EO extraction. The methanol and aqueous extracts of L. camara were obtained by maceration in methanol and water, respectively. An in vivo pesticidal bioassay was conducted to determine the biocidal potential of L. camara leaves using aqueous extract, methanolic extract, EO and water (as control) via two modes of application (spraying and drenching). The data were analysed using ANOVA and DMRT. The EO treatment gave the best control of the pests and resulted in higher fruit yield (1821 g · plant‒1) compared to the control (512.5 g · plant‒1). Thus, the EO from L. camara leaves demonstrated promising biocidal potential and can be effectively used to protect tomatoes against pests for increased fruit yield.