Toxicity of Oils Formulation as a New Useful Tool in Crop Protection for Insect Pest s Control
Oils remain an important tool to manage certain pest problems on fruit trees, shade trees, woody ornamental plants, flowering plants, vegetables and other herbaceous plants. Essential oils are particularly abundant in some families of plants such as Conifers, Rutaceae, Umbelliferae, Myrtaceae and Labiatae. This study investigates the effects of essential oil formulations as a new tool in crop protection against the most serious insect pests around the world. Beside the domestic uses, essential oils present applications in agriculture and the food industry. Some oils have been developed and are eventually registered for crop use to suppress a variety of insect pests. Many plant essential oils show a broad spectrum of activity against insect pests (e.g. scales, aphids, mites) Mustard essential oil as part of a sustained release formulation containing insecticide, microbicide and repellent substances absorbed onto silica and silane compounds is used to prevent infestation of mites in feed. Attractant adhesive films with essential oils are prepared to control insects in agriculture and horticulture crops, and essential oils can also be incorporated with polymers. These natural chemicals have multiple modes of action, including antifeedant and repellent activities, moulting and respiration inhibition, growth and fecundity reduction and cuticle disruption, and can act as a contact, fumigant, repellent, antifeedant, and oviposition inhibition toxicants. Furthermore, the essential oils have been widely used as anti parasitical, bactericidal, fungicidal, antiviral and insecticidal activities. These multiple modes of action are advantageous because they delay the development of resistance among arthropod pest populations. Efforts can be further focused on plant essential oils or phytochemicals as potential sources of commercial insect control agents, and significant relationships among adulticidal, nymphicidal and ovicidal activities of the test oils might be observed. Consequently, a diversified use of essential oils by the development of their use in the pest management sector could be of both economic and ecologic benefits.