Formulation based on essential oils and its use in controlling fruit flies, specifically the species drosophila suzukii

Abstract

The invention relates to a mixture of essential oils comprising, relative to the total volume of the mixture of essential oils, 2 to 35 vol% eugenol; and 2 to 35 vol% methyl salicylate; and 2 to 35 vol% carvone. The invention also relates to the use of this mixture of essential oils in phytosanitary compositions for the pesticide treatment of plants, in particular for combating fruit flies, more preferably the species Drosophila suzukii.

Description

[0001] Formulation based on essential oils and its use in the control of fruit flies, specifically the species Drosophila suzukii

[0002] Field of invention

[0003] The present invention relates to a combination of essential oils and formulations comprising such a combination useful for the insecticide treatment of plants, in particular in the control of fruit flies, specifically the species Drosophila suzukii.

[0004] Technical background

[0005] Drosophila suzukii is a dipteran insect of the Drosophiladae family. This fly, native to Asia, was identified in France in the 2010s. It causes significant damage to many fruit species, particularly cherries and small red fruits (strawberries, raspberries, blackberries, blueberries). This invasive pest has, since 2010, widely colonized French orchards, becoming the main pest of cherry crops and has almost replaced the endemic cherry fly species, Ragoletis cerasi. Its high potential for damage and invasion is explained by its polyphagy, its rapid reproduction capacity and its mobility. In addition, Drosophila suzukii is particularly impactful because, unlike other species historically encountered, it is capable of laying eggs in firm fruits at an early stage of ripening.This species of fly can therefore lay eggs in fruit at different stages of maturity, causing very significant damage.

[0006] The only methods of controlling Drosophila suzukii, sufficiently effective to date, to maintain a satisfactory level of health, remains protection by synthetic phytosanitary products. The three reference chemical active substances and sufficiently effective to treat Drosophila suzukii on cherries have been withdrawn from the market or are in the process of being withdrawn from the market, due to their toxicity to humans (operator who treats the plots but also the consumer; eggs are laid on the fruit, the treatment is applied directly to the organ consumed) and the environment (substances not specific to Drosophila suzukii, contamination of soil and groundwater, etc.). Dimethoate was withdrawn from the market in 2016. Phosmet was withdrawn from the market in 2022. The last remaining active substance, widely used by producers in 2023, usable only under derogatory MA is cyantraniliprole.Also known from US20210298299 are synthetic aromatic chemicals for pest control.

[0007] There are few truly effective alternatives on the market to chemical control. The alternatives are either very expensive, such as insect nets (over €20,000 investment per hectare) with disadvantages for biodiversity (resurgence of mites), or very ineffective, such as mass trapping.

[0008] As for other synthetic products, such as pyrethroid insecticides, these are broad-spectrum insecticides, which are not sufficiently effective against Drosophila suzukii and generate resistance issues. Moreover, their sustainability on the market for the next 5 years is not guaranteed due to their toxicity.

[0009] Also known from W02019101890 are solutions for attracting insects into a trap containing toxic compounds for the purpose of destroying the insects.

[0010] The technical sustainability of cherry production is no longer assured and the industry is urgently seeking effective solutions against Drosophila suzukii.

[0011] There is therefore an interest in providing a composition which, while responding to the problem of Drosophila suzukii, also responds to socio-environmental, regulatory and economic constraints (costs consistent with market requirements and profitability needs inherent in the sustainability of a business).

[0012] There is therefore an interest in providing effective compositions, particularly against Drosophila suzukii. There is an interest in providing such compositions that do not cause toxicity to plants.

[0013] There is an interest in providing a composition allowing a compromise between the objective of pest control and low harmfulness to humans.

[0014] There is an interest in providing a composition that limits the appearance of resistance phenomena in order to avoid a loss of effectiveness of the product over time.

[0015] There is also an interest in providing such a composition which has a deterrent effect on spawning and does not lead to the death of individuals.

[0016] Summary of the invention

[0017] The invention relates firstly to a mixture of essential oils comprising, relative to the total volume of the mixture of essential oils: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone.

[0018] In one embodiment, the essential oil blend further comprises: from 2 to 35% by volume of limonene; and / or from 2 to 35% by volume of geraniol; and / or from 2 to 35% by volume of citronellol; and / or from 2 to 35% by volume of citronellal, the total of eugenol, methyl salicylate, carvone, limonene, geraniol, citronellol and citronellal represents from 50 to 90% by volume relative to the total volume of the essential oil blend.

[0019] Preferably, the essential oils are chosen from Java citronella essential oil (Cymbopogon winterianus), Ceylon citronella essential oil (Cymbopogon nardus), palmarosa essential oil (Cymbopogon martini), rose geranium essential oil (Pelargonium graveolens), Ceylon cinnamon leaf essential oil (Cinnamomum verum), clove essential oil (Eugenia caryophyllus), allspice essential oil (Pimenta dioica), wintergreen essential oil (Gaultheria fragrantissima), wintergreen essential oil (Gaultheria procumbens), securidaca essential oil (Securidaca longepedonculata), caraway essential oil (Carum carvi), spearmint essential oil (Mentha spicata), dill (Anethum graveolens) or any mixture thereof.

[0020] The present invention relates to a composition Cl comprising, relative to the total volume of the composition Cl: from 60% to 95% by volume, preferably from 80 to 95% by volume, of at least one surfactant; from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of the mixture of essential oils according to the invention; and from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of at least one vegetable oil.

[0021] The present invention also relates to a Cld composition comprising, relative to the total volume of the Cld composition: from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of the mixture of essential oils according to the invention; from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of vegetable oil; from 0.5 to 2% by volume, preferably from 0.5 to 1.5% by volume, of surfactant; from 98% to 99.44% by volume, preferably from 98% to 99% by volume, of water.

[0022] The present invention also relates to a composition C2 comprising, relative to the total volume of composition C2: from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of a mixture of essential oils according to the invention; from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of at least one esterified vegetable oil; and from 40 to 85% by volume, preferably from 70 to 85% by volume, of water.

[0023] The present invention also relates to a composition C2d comprising, relative to the total volume of composition C2d: from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of the mixture of essential oils according to the invention; from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of esterified vegetable oil; from 99.4 to 99.9% by volume, preferably from 99.4 to 99.7% by volume, of water.

[0024] The present invention also relates to the use of the mixture of essential oils according to the invention or of the compositions Cl, Cid, C2, C2d, for the pesticide treatment of plants, in particular in the fight against fruit flies, specifically the species Drosophila suzukii.

[0025] The present invention also relates to a method for pesticide treatment of plants, in particular in the fight against fruit flies, specifically the species Drosophila suzukii, comprising the application to the plant, preferably by foliar application, of a composition comprising 0.5 to 2.5 l, preferably 0.5 to 1.5 l of a composition Cl or C2 per 100 l of phytosanitary treatment composition. Detailed description

[0026] Figure 1 shows the evolution over time of the mortality rate of insects in contact with a composition according to the invention and a control composition.

[0027] The invention is now described in more detail and in a non-limiting manner in the following description.

[0028] Unless otherwise stated, all percentages are by volume.

[0029] In this text, the quantities indicated for a given species may apply to this species according to all its definitions (as mentioned in this text), including the more restricted definitions.

[0030] Essential Oil Blend

[0031] The invention relates firstly to a mixture of essential oils comprising, relative to the total volume of the mixture of essential oils: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone.

[0032] The mixture of essential oils of the invention may further comprise, relative to the total volume of the mixture of essential oils: from 2 to 35% by volume of limonene; and / or from 2 to 35% by volume of geraniol; and / or from 2 to 35% by volume of citronellol; and / or from 2 to 35% by volume of citronellal.

[0033] The invention preferably relates to a mixture of essential oils comprising, relative to the total volume of the mixture of essential oils: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone; and from 2 to 35% by volume of limonene.

[0034] A particular essential oil mixture according to the invention is an essential oil mixture comprising, relative to the total volume of the essential oil mixture: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone; and from 2 to 35% by volume of geraniol; and optionally from 2 to 35% by volume of limonene.

[0035] Another particular essential oil mixture according to the invention is an essential oil mixture comprising, relative to the total volume of the essential oil mixture: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone; and from 2 to 35% by volume of citronella I; and optionally from 2 to 35% by volume of limonene.

[0036] Another particular essential oil mixture according to the invention is an essential oil mixture comprising, relative to the total volume of the essential oil mixture: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone; and from 2 to 35% by volume of citronella I; and from 2 to 35% by volume of geraniol.

[0037] Another particular essential oil mixture according to the invention is an essential oil mixture comprising, relative to the total volume of the essential oil mixture: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone; and from 2 to 35% by volume of limonene; and from 2 to 35% by volume of geraniol; and from 2 to 35% by volume of citronellol; and from 2 to 35% by volume of citronellal.

[0038] Preferably, the total of eugenol, methyl salicylate, carvone, limonene, geraniol, citronellol and citronellal represents from 50 to 90% by volume relative to the total volume of the mixture of essential oils. The mixture of essential oils according to the invention may consist of 3 to 13 different essential oils.Essential oils that can be used include Java citronella oil (Cymbopogon winterianus), Ceylon citronella oil (Cymbopogon nardus), palmarosa oil (Cymbopogon martini), rose geranium oil (Pelargonium graveolens), Ceylon cinnamon leaf oil (Cinnamomum verum), clove oil (Eugenia caryophyllus), allspice oil (Pimenta dioica), wintergreen oil (Gaultheria fragrantissima), wintergreen oil (Gaultheria procumbens), securidaca oil (Securidaca longepedonculata), caraway oil (Carum carvi), spearmint oil (Mentha spicata), dill (Anethum graveolens) or any mixture thereof.

[0039] A person skilled in the art can easily determine the essential oils to be mixed and the quantity of these oils in order to obtain the mixture of essential oils according to the invention.

[0040] Essential oils being corrosive and acidic products, they cannot be used pure at the risk of causing burns. The mixture of essential oils according to the invention, which is a concentrated mixture, must therefore be formulated in a composition suitable for phytosanitary use and in particular for use by spraying.

[0041] Phytosanitary composition

[0042] Thus, in a particular embodiment, the present invention relates to a composition (Cl), preferably a phytosanitary composition (Cl), comprising, relative to the total volume of the composition (Cl): from 60% to 95% by volume, preferably from 80 to 95% by volume, of at least one surfactant; from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of the mixture of essential oils according to the invention; and from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of at least one vegetable oil.

[0043] Preferably, in the composition (Cl) of the invention the volume ratio of the mixture of essential oils to the volume of at least one vegetable oil is between 0.5 and 2, preferably is approximately 1. The molecules composing the essential oils have low molecular weights and are, in fact, more volatile and more fragile to destructuring in solution. Thus, the combination of the essential oils with at least one vegetable oil makes it possible to protect the molecules contained in the essential oils and consequently to preserve the biochemical properties of the essential oils. In a particularly advantageous manner, the mixture of essential oils according to the invention is initially mixed with at least one vegetable oil, thus forming an oily solute which is then mixed with at least one surfactant. The mixture with the surfactant generates a microencapsulation of the oily solute and the formation of micelles.

[0044] The composition (Cl) according to the invention is therefore preferably obtained according to the following process: a) mixing at least one vegetable oil with the mixture of essential oils according to the invention; b) mixing the composition obtained in step a) with at least one surfactant.

[0045] The vegetable oil used in the composition (Cl) is preferably a vegetable oil rich in unsaturated fatty acids (preferably between 60 and 90% by weight) and saturated fatty acids (between 40 and 10% by weight) and having a high molecular weight (preferably between 14 and 26 carbon atoms). Among the vegetable oils which can be used in the context of the present invention, mention may in particular be made of coconut oil, olive oil, palm oil, rapeseed oil, sunflower oil or any of their mixtures.

[0046] In the context of the present invention, the surfactant may be a composition comprising a surfactant, for example a composition comprising water and a surfactant.

[0047] The surfactant is an amphiphilic compound having a lipophilic (apolar) part and a hydrophilic (polar) part. The surfactant used in the composition (Cl) according to the invention can be any type of surfactant typically used in phytosanitary compositions, preferably it is based on vegetable oil. The surfactant of the invention is preferably black soap (obtained from olive and / or linseed oil).

[0048] Preferably, the composition (Cl) of the invention comprises from 0.15 to 7% by volume, preferably from 0.15 to 1.5% by volume, of eugenol, from 0.15 to 7% by volume, preferably from 0.15 to 1% by volume, of methyl salicylate, from 0.15 to 7% by volume, preferably from 0.15 to 1% by volume, of carvone and optionally from 0.15 to 7% by volume, preferably from 0.15 to 0.5% by volume, of citronellal and / or from 0.15 to 7% by volume, preferably from 0.15 to 0.5% by volume, of citronellol and / or from 0.15 to 7% by volume, preferably from 0.15 to 0.5% by volume, of geraniol ... volume, preferably from 0.15 to 0.5% by volume of limonene relative to the total volume of the composition (Cl).

[0049] Before use on plants, the composition (Cl) may be diluted in a phytosanitary treatment composition (also called slurry) (to form a composition (Cld) comprising, relative to the total volume of the composition (Cld): from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of the mixture of essential oils according to the invention; from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of vegetable oil; from 0.5 to 2% by volume, preferably from 0.5 to 1.5% by volume, of surfactant; from 98% to 99.44% by volume, preferably from 98% to 99% by volume, of water.

[0050] Preferably, the composition (Cld) of the invention comprises, relative to the total volume of the composition (Cld), from 0.002% to 0.1% by volume, preferably from 0.002 to 0.02% by volume, of eugenol, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.02% by volume of methyl salicylate, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.01% by volume of carvone and optionally from 0.002% to 0.1% by volume, preferably from 0.002 to 0.009% by volume, of citronellal, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.009% by volume, of citronellol, 0.002% to 0.1% by volume, preferably 0.002 to 0.009% by volume, of geraniol, 0.002% to 0.1% by volume, preferably 0.002 to 0.009% by volume, of limonene.

[0051] In another embodiment, the present invention relates to a composition (C2), preferably a phytosanitary composition (C2), comprising, relative to the total volume of the composition (C2): from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of a mixture of essential oils according to the invention; from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of at least one esterified vegetable oil; and from 40 to 85% by volume, preferably from 70 to 85% by volume, of water.

[0052] Preferably, in composition (C2) the ratio of the volume of the mixture of essential oils to the volume of esterified vegetable oil is between 0.5 and 2, preferably is approximately 1.

[0053] An esterified vegetable oil according to the invention can be obtained by reaction between a vegetable oil and a fatty alcohol.

[0054] Preferably, the vegetable oil according to the invention is chosen from olive oil, coconut oil, palm oil, sunflower oil, linseed oil, sweet almond oil, macadamia oil, argan oil, rapeseed oil, camelina oil, rice oil, wheat germ oil, or any of their mixtures.

[0055] Preferably, the fatty alcohol is glycerol.

[0056] Composition (C2) of the invention is preferably obtained according to the following process: a) Heating the esterified vegetable oil to make it more liquid; b) Mixing the esterified vegetable oil obtained in step a) with the mixture of essential oils; and c) Mixing the solution obtained in step b) with water.

[0057] The composition (C2) of the invention preferably comprises from 0.3 to 7% by volume, preferably from 0.3 to 2% by volume, of eugenol, from 0.3 to 7% by volume, preferably from 0.3 to 2% by volume, of methyl salicylate, from 0.3 to 7% by volume, preferably from 0.3 to 1.5% by volume, of carvone and optionally from 0.3 to 7% by volume, preferably from 0.3 to 1% by volume, of citronellal and / or 0.3 to 7% by volume, preferably from 0.3 to 1% by volume, of citronellol and / or 0.3 to 7% by volume, preferably from 0.3 to 1% by volume, of geraniol, and / or 0.3 to 7% by volume, preferably from 0.3 to 1% by volume, of limonene.

[0058] Before use on plants, the composition (C2) according to the invention can be diluted in a phytosanitary treatment composition (also called slurry) to form a composition (C2d) comprising, relative to the total volume of the composition (C2d): from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of the mixture of essential oils according to the invention; from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of esterified vegetable oil; from 99.4 to 99.9% by volume, preferably from 99.4 to 99.7% by volume, of water.

[0059] Preferably, the composition (C2d) of the invention comprises, relative to the total volume of the composition (C2d), from 0.002% to 0.1% by volume, preferably from 0.002 to 0.02% by volume, of eugenol, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.02% by volume of methyl salicylate, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.01% by volume of carvone and optionally from 0.002% to 0.1% by volume, preferably from 0.002 to 0.009% by volume, of citronellal, from 0.002% to 0.1% by volume, preferably from 0.002 to 0.009% by volume, of citronellol, 0.002% to 0.1% by volume, preferably 0.002 to 0.009% by volume, of geraniol, 0.002% to 0.1% by volume, preferably 0.002 to 0.009% by volume, of limonene.

[0060] The present invention also relates to the use of esterified vegetable oil, in particular as a stabilizer, for the emulsification of a mixture of essential oils in water.

[0061] In the context of the present invention, "water" means any type of water, such as, for example, demineralized water, ionized water, salt water, water in which plants or vegetables have been infused or macerated, etc.

[0062] Use and processing method

[0063] The present invention also relates to the use of a mixture of essential oils according to the invention or of any one of the compositions (Cl), (Cld), (C2) or (C2d) according to the invention for the pesticide treatment, preferably insecticide treatment, of plants, in particular for the control of fruit flies, more preferably the species Drosophila suzukii.

[0064] The present invention also relates to the use of a mixture of essential oils according to the invention in a phytosanitary composition for its pesticidal effect and in particular for its insecticidal effect, preferably on the fruit fly, more preferably the species Drosophila suzukii. Particularly advantageously, the compositions according to the invention act as a repellent and thus limit egg-laying. The present invention also relates to a pesticide treatment method, preferably an insecticide treatment, in particular for combating the fruit fly, more preferably the species Drosophila suzukii, comprising the application to plants of a composition (Cld) or (C2d) according to the invention.

[0065] Preferably, compositions (Cl) and (C2) are used at a rate of 0.5L to 2.5L, preferably 0.5 to 1.5L, per 100L of phytosanitary treatment composition (also called slurry). In one embodiment, the phytosanitary treatment composition is water or water comprising at least one active phytosanitary compound.

[0066] Preferably, the mixture of essential oils or the compositions (Cl), (Cld), (C2) or (C2d) according to the invention are used by spraying on plants, in particular on the leaves of plants.

[0067] The use of the compositions according to the invention relates to all types of plants and in particular all types of crops. In a particularly preferred manner, the use according to the invention is particularly suitable for outdoor treatment, in particular for open-field crops but also for greenhouse crops. Preferably, the invention relates to fruit crops (cherries, figs, etc.) and market garden crops (strawberries, etc.).

[0068] The invention will be explained in more detail in the following examples.

[0069] Examples

[0070] Unless otherwise stated, percentages are expressed by volume relative to the total volume of the composition.

[0071] Example 1:

[0072] Compositions according to the invention

[0073] A composition (Cl) is prepared in accordance with the invention and comprising:

[0074] 90.90% by volume of black soap;

[0075] 4.55% by volume of olive oil; and

[0076] 1 to 1.25% by volume of eugenol, 0.8 to 1% by volume of methyl salicylate, 0.4 to 0.6% by volume of carvone, 0.2 to 0.4% by volume of citrone Ila I, 0.1 to 0.4% by volume of citronellol, 0.1 to 0.4% by volume of geraniol, 0.2 to 0.5% by volume of limonene.

[0077] A composition (C2) is prepared in accordance with the invention and comprising:

[0078] 83.34% by volume of water;

[0079] 8.33% by volume of olive oil esterified with glycerol;

[0080] 1 to 1.5% by volume of eugenol, 1.5 to 1.8% by volume of methyl salicylate, 0.7 to 1.5% by volume of carvone, 0.4 to 0.8% by volume of citrone Ila I, 0.4 to 0.8% by volume of citronellol, 0.3 to 0.8% by volume of geraniol, 0.5 to 0.83% by volume of limonene

[0081] In the following treatments, all the compositions are sprayed onto the plants to be treated.

[0082] Plant treatment

[0083] The Cl composition was tested on cherry trees, Belgian variety, at a rate of 7.5L per 500L of spray volume, 5 treatments every 7 days. Then, the fruit pitted by Drosophila suzukii was noted, 10 days after the last treatment. The trees treated with the Cl composition presented: 0% pitted fruit, compared to the untreated control: 28% pitted fruit, compared to the producer's chemical reference: 0% pitted fruit. Product efficacy = 100%, equivalent to the chemical reference

[0084] Composition C2 was tested on Belgian cherry trees, at a rate of 5L per 500L of spray volume, 3 treatments every 7 days. Then, the fruit pitted by Drosophila suzukii was noted, 4 days after the last treatment. The trees treated with composition C2 showed: 3.3% pitted fruit, compared to the untreated control: 96% pitted fruit, compared to the producer's chemical reference: 3.3% pitted fruit. Product efficacy = 96.7%, equivalent to the chemical reference Example 2:

[0085] Compositions according to the invention and comparative:

[0086] A control composition (CTI) was prepared. This composition comprises 99.85% by volume of water and 0.15% by volume of esterified olive oil.

[0087] A composition C3 according to the invention was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified olive oil and 0.15% by volume of a mixture of essential oils comprising 18.3% by volume of carvone, 19.4% by volume of methyl salicylate, 35% by volume of eugenol and 5.1% by volume of limonene.

[0088] A composition C4 according to the invention was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified olive oil and 0.15% by volume of a mixture of essential oils comprising 11.2% by volume of carvone, 7% by volume of citronellal, 2.2% by volume of citronellol, 21.3% by volume of eugenol, 4.4% by volume of geraniol, 8.6% by volume of limonene and 9.7% by volume of methyl salicylate.

[0089] Tests

[0090] 10 Drosophila suzukii were released into cages for 24 hours. Into these cages were added 6 small pots containing 20ml of blueberry jelly (30% frozen blueberry, 65% water and 3% agar agar + 0.3% Nipagin). This jelly constitutes an oviposition substrate. 4 repetitions were carried out.

[0091] Of the 6 substrates, 2 received 3ml of the CTI composition, 2 others received 3ml of the C3 composition and the last 2 received 3ml of the C4 composition.

[0092] After 24 h in the cage, the substrates were removed and the surface eggs were counted with a binocular microscope. The count data were transformed into relative proportions for each replicate and are presented in the table below:

[0093] A Post-hoc Test was performed to compare the means of proportions two by two, it appears that a significant difference is present between the three formulas (p. value less than 0.05).

[0094] The presence of the compositions according to the invention makes it possible to significantly reduce the number of eggs laid compared to the control. These tests demonstrate that the compositions according to the invention make it possible to limit egg laying and have a repellent effect on Drosophila suzukii.

[0095] Example 3:

[0096] Compositions according to the invention and comparative:

[0097] A control composition (CT2) was prepared. This composition comprises 99.85% by volume of water and 0.15% by volume of esterified olive oil.

[0098] A comparative CCI composition was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 95% by volume of limonene.

[0099] A comparative composition CC2 was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 56% by volume of carvone and 40% by volume of limonene.

[0100] A comparative composition CC3 was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 43% by volume of methyl salicylate and 52% by volume of limonene. A comparative composition CC4 was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 39.05% by volume of eugenol and 42.75% by volume of limonene.

[0101] A composition according to the invention C5 was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 28% by volume of carvone, 19.4% by volume of methyl salicylate, 21.3% by volume of eugenol and 20% by volume of limonene.

[0102] Tests

[0103] 10 Drosophila suzukii were released into cages for 24 hours. Into these cages were added 6 small pots containing 20ml of blueberry jelly (30% frozen blueberry, 65% water and 3% agar agar + 0.3% Nipagin). This jelly constitutes an oviposition substrate.

[0104] Each of the substrates received 3 ml of a different composition CT2, CCI, CC2, CC3, CC4 and C5. 8 repetitions were carried out.

[0105] After 24 h in the cage, the substrates were removed and the surface eggs were counted with a binocular microscope. The count data were transformed into relative proportions for each replicate and are presented in the table below:

[0106] A Post-hoc Test was carried out to compare the means of proportions two by two, it appears that a significant difference is present between the three formulas (p. value less than 0.05). The results demonstrate that the composition according to the invention is clearly more effective in reducing the number of eggs laid on the substrate, highlighting a synergy of the different compounds.

[0107] Example 4:

[0108] Compositions according to the invention and comparative:

[0109] A control composition (CT3) was prepared. This composition comprises 99.85% by volume of water and 0.15% by volume of esterified olive oil.

[0110] A composition according to the invention (C6) was prepared. This composition comprises 99.7% by volume of water, 0.15% by volume of esterified oil and 0.15% by volume of a mixture of essential oils comprising 11.2% by volume of carvone, 7% by volume of citronellal, 2.2% by volume of citronellol, 21.3% by volume of eugenol, 4.4% by volume of geraniol, 8.6% by volume of limonene and 9.7% by volume of methyl salicylate.

[0111] Tests

[0112] Tubes containing 5ml of nutrient medium (NutriFlyTM) were impregnated with 4ml of the treatment, and the supernatant was then emptied. A drying step was performed to prevent excess liquid in the tubes and to distribute the active substances of the treatment evenly on the walls. The tubes were kept in constant rotation during the process using a sausage roller (without heating resistance). Once drying was complete, 20 adult Drosophila suzukii aged 4 to 14 days were added to each of the tubes. The tubes were kept in incubation in the culture chamber (21°C and 65% humidity) for 48h. Subsequently, the individuals were transferred to new untreated tubes every 7 days and kept in incubation until the end of the 23-day follow-up. The mortality rate was monitored daily and is shown in Figure 1.

[0113] The results presented in Figure 1 show that the mortality rate of Drosophila suzukii in contact with the C6 composition according to the invention is not statistically different from that of the controls. The evolution of the mortality rate according to the two treatment methods does not show any significant difference in the 23 days following contact with the compositions showing that the compositions according to the invention have a repellent and non-lethal action.

Claims

Claims 1. A mixture of essential oils comprising, relative to the total volume of the mixture of essential oils: from 2 to 35% by volume of eugenol; and from 2 to 35% by volume of methyl salicylate; and from 2 to 35% by volume of carvone.

2. The essential oil blend of claim 1 further comprising: from 2 to 35% by volume of limonene; and / or from 2 to 35% by volume of geraniol; and / or from 2 to 35% by volume of citronellol; and / or from 2 to 35% by volume of citronellal, the total of eugenol, methyl salicylate, carvone, limonene, geraniol, citronellol and citronellal represents from 50 to 90% by volume relative to the total volume of the essential oil blend.

3. A mixture of essential oils according to claim 1 further comprising from 2 to 35% by volume of limonene.

4. Mixture of essential oils according to claim 1 or 3 further comprising: - from 2 to 35% by volume of geraniol; or - from 2 to 35% by volume of citronellal; or - from 2 to 35% by volume of geraniol and from 2 to 35% by volume of citronellal.

5. A mixture of essential oils according to any one of claims 1 to 4, wherein the essential oils are chosen from Java citronella essential oil (Cymbopogon winterianus), Ceylon citronella essential oil (Cymbopogon nardus), palmarosa essential oil (Cymbopogon martini), rose geranium essential oil (Pelargonium graveolens), Ceylon cinnamon leaf essential oil (Cinnamomum verum), clove bud essential oil clove (Eugenia caryophyllus), allspice (Pimenta dioica) oil, wintergreen (Gaultheria fragrantissima) oil, wintergreen (Gaultheria procumbens) oil, securidaca (Securidaca longepedonculata) oil, caraway (Carum carvi) oil, spearmint (Mentha spicata) oil, dill (Anethum graveolens) oil or any mixture thereof.

6. Composition Cl comprising, relative to the total volume of composition Cl: from 60% to 95% by volume, preferably from 80 to 95% by volume, of at least one surfactant; from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of the mixture of essential oils according to any one of claims 1 to 5; and from 2.5 to 20% by volume, preferably from 2.5 to 10% by volume, of at least one vegetable oil.

7. Composition Cld comprising, relative to the total volume of the composition Cld: from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of the mixture of essential oils according to any one of claims 1 to 5; from 0.03 to 0.3% by volume, preferably from 0.03 to 0.15% by volume, of vegetable oil; from 0.5 to 2% by volume, preferably from 0.5 to 1.5% by volume, of surfactant; from 98% to 99.44% by volume, preferably from 98% to 99% by volume, of water.

8. Composition C2 comprising, relative to the total volume of composition C2: from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of a mixture of essential oils according to any one of claims 1 to 5; from 7.5 to 30% by volume, preferably from 7.5 to 15% by volume, of at least one esterified vegetable oil; and from 40 to 85% by volume, preferably from 70 to 85% by volume, of water.

9. Composition C2d comprising, relative to the total volume of composition C2d: from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of the mixture of essential oils according to any one of claims 1 to 5; from 0.05 to 0.30% by volume, preferably from 0.05 to 0.15% by volume, of esterified vegetable oil; from 99.4 to 99.9% by volume, preferably from 99.4 to 99.7% by volume, of water.

10. Use of the mixture of essential oils according to any one of claims 1 to 5 or of the compositions according to any one of claims 6 to 9, for the pesticide treatment of plants, in particular in the fight against fruit flies, more preferably the species Drosophila suzukii.

11. Method for pesticide treatment of plants, in particular in the fight against fruit flies, more preferably the species Drosophila suzukii, comprising the application to the plant, preferably by foliar application, of a composition comprising 0.5 to 2.5 I, preferably 0.5 to 1.5 I of composition Cl or C2 according to claims 6 or 8 per 100 l of phytosanitary treatment composition.

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