Toxics or Lures? Biological and Behavioral Effects of Plant Essential Oils on Tephritidae Fruit Flies

Abstract

The family Tephritidae (Diptera) includes species that are highly invasive and harmful to crops. Due to globalization, international trade, and human displacement, their spread is continuously increasing. Unfortunately, the control of tephritid flies is still closely linked to the use of synthetic insecticides, which are responsible for detrimental effects on the environment and human health. Recently, research is looking for alternative and more eco-friendly tools to be adopted in Integrated Pest Management (IPM) programs. In this regard, essential oils (EOs) and their main compounds represent a promising alternative to chemical insecticides. EOs are made up of phytoconstituents formed from the secondary metabolism of many plants and can act as attractants or toxics, depending on the dose. Because of this unique characteristic, EOs and their main constituents are promising tools that can be used both in Sterile Insect Technique (SIT) programs and in the “lure and kill” technique, exploiting the attractiveness of the product in the former case and its toxicity in the latter. In this article, current knowledge on the biological and behavioral effects of EOs and their main constituents on tephritid fruit flies is reviewed, mainly focusing on species belonging to the Anastrepha, Bactrocera, Ceratitis, and Zeugodacus genera. The mechanisms of action of EOs, their real-world applications, and challenges related to their use in IPM are critically discussed.

Identification of host plant volatile stimulants of Anastrepha fraterculus male courtship behavior

“…Toxic effects of limonene and EOs containing high proportions of limonene were previously reported for tephritid species, including A. fraterculus (Salvatore et al, 2004;Papachristos et al, 2009;Ruiz et al, 2014;Papanastasiou et al, 2017;Oviedo et al, 2018Oviedo et al, , 2020, where survival, emergence, and fecundity were affected by exposure to these phytochemicals. In agreement, Ruiz et al (2021) have found that only the EO of lemon, as opposed to the EOs of orange and grapefruit, was able to stimulate A. fraterculus males. Among these three EOs, lemon EO had the lowest R-limonene concentration (Ruiz et al, 2015;González-Mas et al, 2019).…”

Synthesis of Cyclic Fragrances via Transformations of Alkenes, Alkynes and Enynes: Strategies and Recent Progress

“…The utilization of machine learning, artificial intelligence and brain–computer interfaces for fragrance design, synthesis and quantitative olfactory studies is expected to show rapid growth [ 165 , 166 , 167 , 168 , 169 , 170 , 171 , 172 , 173 ]. The safety, therapeutic efficacy, allergic effect and biodegradability of these new fragrances should also be investigated further, especially in the case of fragrances containing new scaffolds [ 174 , 175 , 176 , 177 , 178 , 179 , 180 ].…”

Toxicity of Some Essential Oils Constituents against Oriental Fruit Fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae)

“…In several recent studies, plant essential oils (EOs) have been shown to have antifungal, antimicrobial, cytostatic, and insecticidal properties [ 14 , 15 ]. Essential oils are natural combinations of chemicals with low molecular weight, volatility, and lipophilic nature found in various plant families, including Asteraceae, Apiaceae, Lamiaceae, Myrtaceae, Lauraceae, and Rutaceae [ 15 , 16 ]. Essential oil components (EOCs) are classified into four classes according to their chemical structure: terpenes, terpenoids, phenylpropenes, and others.…”

“…Essential oil components (EOCs) are classified into four classes according to their chemical structure: terpenes, terpenoids, phenylpropenes, and others. They may also contain a diversity of functional groups such as hydrocarbons (monoterpenes, sesquiterpenes, and aliphatic hydrocarbons); oxygenated compounds (monoterpene and sesquiterpene alcohols, aldehydes, ketones, esters, and other oxygenated compounds); and sulphur and nitrogen-containing compounds (thioesters, sulfides, isothiocyanates and nitrile) [ 15 , 16 , 17 ]. Components of essential oils exert their activities (mode of action) on pests in a neurotoxic way, for example, like gamma-aminobutyric acid (GABA), insect growth regulator (IGR), octopamine synapses (OS), impending digestive enzymes, inhibition of glutathione S-transferase (GST), cytochromes P450 (CYPs), and acetylcholinesterase (AchE) inhibitors for effective control in pre-and post-harvest agricultural techniques [ 18 , 19 , 20 ].…”

“…Components of essential oils exert their activities (mode of action) on pests in a neurotoxic way, for example, like gamma-aminobutyric acid (GABA), insect growth regulator (IGR), octopamine synapses (OS), impending digestive enzymes, inhibition of glutathione S-transferase (GST), cytochromes P450 (CYPs), and acetylcholinesterase (AchE) inhibitors for effective control in pre-and post-harvest agricultural techniques [ 18 , 19 , 20 ]. Moreover, various potential essential oils and their constituents belonging to terpenes and phenylpropanoids (α-pinene, β- pinene limonene and zingerone) showed effectiveness in integrated pest management (IPM), sterile insect technique (SIT), lure and kill techniques against many fruit flies such as Ceratitis capitata , B. dorsalis , B. correcta , B. philippinensis , Anastrepha and Zeugodacus genera [ 15 , 16 ].…”