POTENTIALITY OF ANONACEOUS PLANT PRODUCTS AS BIOINSECTICIDES FOR AGRICULTURAL PEST CONTROL

Abstract

The use of insecticidal plants has increased greatly worldwide due to the presence of biodegradable active compounds that are less toxic to mammals and the environment and are potentially more suitable for pest management. The Annonaceae family is one of the most promising in this field for having natural compounds with proven insecticidal action for various agricultural pests and, by the presence of acetogenins, bioactive substances that act on mitochondria, inhibiting NADH, causing the death of insects. Several species of this family have been studied, especially the soursop (Annona muricata L.) and sugar apple (Annona squamosa L.) because they are fruit trees with commercial production already established in Brazil. Different parts of plants of the Annonaceae family have already been tested for their biological action against pests, such as leaves, roots, bark, branches, but it was the seeds that found the greatest diversity and concentration of active ingredients of interest. In addition to being the parts with the highest toxic activity, seeds are readily available as waste material for industrial pulp processing. Aqueous, ethanolic and hexanic extracts and also seed formulations of these species have already been successfully tested in the control of some insect species of Lepidoptera, Coleoptera and Hemiptera. Some difficulties for the field use of plant extracts are: chemical standardization of the active ingredients, quality control, difficulty of legal registration, practical application and persistence in the field, which is generally very low requiring a larger number of applications, thus requiring studies to find formulations best suited for field application. The development of a microencapsulated formulation could facilitate the application of the extract in the field, as the active ingredient is protected in small droplets surrounded by a thin matrix film, improving its stability and effectiveness by slower release increasing persistence in the environment. Therefore, investments are needed in new technologies for the definitive and safe insertion of these plant products in the market, such as studies on mechanisms of action, phytotoxicity, selectivity to beneficial insects, real safety to mammals and other vertebrates.