Essential Oils in Insect Control: Low-Risk Products in a High-Stakes World

Abstract

In recent years, the use of essential oils (EOs) derived from aromatic plants as low-risk insecticides has increased considerably owing to their popularity with organic growers and environmentally conscious consumers. EOs are easily produced by steam distillation of plant material and contain many volatile, low-molecular-weight terpenes and phenolics. The major plant families from which EOs are extracted include Myrtaceae, Lauraceae, Lamiaceae, and Asteraceae. EOs have repellent, insecticidal, and growth-reducing effects on a variety of insects. They have been used effectively to control preharvest and postharvest phytophagous insects and as insect repellents for biting flies and for home and garden insects. The compounds exert their activities on insects through neurotoxic effects involving several mechanisms, notably through GABA, octopamine synapses, and the inhibition of acetylcholinesterase. With a few exceptions, their mammalian toxicity is low and environmental persistence is short. Registration has been the main bottleneck in putting new products on the market, but more EOs have been approved for use in the United States than elsewhere owing to reduced-risk processes for these materials.

Acaricidal Potentials of the Terpene-rich Essential Oils of Two Iranian <i>Eucalyptus</i> Species against <i>Tetranychus urticae</i> Koch

“…In general, essential oils are low-risk products in it is one of the most attractive features of these bio-agents. The popular essential oils such as chamomile, lavender, clove, eucalyptus, and anise have an oral LD 50 value ranging from 2,000 to 5,000 mg/kg in rats while these values were 267 mg/kg for chlordimeform and 163 mg/kg demethylchlordimeform as synthetic acaricides 13 .…”

“…Essential oils are by-products of plant metabolism and their extraction in laboratory scale is carried out by hydrodistillation with a Clevenger type apparatus 13 .…”

Chemical Composition and Insecticidal Activities of Essential Oils of Myrtaceae against Tribolium castaneum (Coleoptera: Tenebrionidae)

“…They are secondary plant metabolites, aromatic in nature, and give a distinctive odour or flavour to a plant [6]. Chemically, they are complex mixtures comprised of a large number of constituents in variable ratios [7].…”

Chemical composition and insecticidal properties of essential oil from aerial parts of <i>Mosla soochowensis</i> against two grain storage insects

“…), commonly known as the maize weevil, and Tribolium castaneum (Herbst), commonly called the red flour beetle, have destructive effects on stored grain products [1], and infestations are typically controlled by fumigation techniques [2]. However, excessive use of synthetic fumigants and insecticides has several detrimental effects, including but are not limited to insecticide resistance, environmental contamination, and damage to human health and other non-target organisms [2,3]. Research into alternative treatments has shown that essential oils and their constituents possess insecticidal properties against many stored-product insect pests [4][5][6]; therefore, these may be alternatives to currently used fumigants and insecticides.…”