FR3120769A1 - METHOD FOR PREVENTIVE TREATMENT OF A PLANT - Google Patents

Abstract

METHOD FOR PREVENTIVE TREATMENT OF A PLANT The present invention relates to a method for the preventive treatment of a plant to prevent infestation by a parasite, consisting in applying to said plant a composition comprising a vegetable oil before the appearance of the infestation. Figure for abstract: none

Description

METHOD FOR PREVENTIVE TREATMENT OF A PLANT

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a process for the preventive treatment of a plant in order to protect a plant for an entire season from infestation by a parasite, such as a mite, an insect or a pathogen for example.

STATE OF THE ART

In horticulture and agriculture, insecticides and fungicides, generally referred to as pesticides, are widely used to treat plants against insects and diseases that degrade plants and reduce yield. cultures.

Pesticides are typically foliar, i.e. they are applied to the leaves and absorbed by them.

The use of alternative solutions, showing effectiveness in the fight against insects and diseases, are interesting because they make it possible to reduce the use of pesticides, or at least the number of applications of these pesticides, but remain to this day almost non-existent.

Professionals use the technical data available to them (plant health report, Fredon alerts) in order to apply plant protection products at the right time. Conversely, the amateur gardener only treats when the infestation is visible, which limits the effectiveness of curative products because the problem is then well established and the plant has already been degraded by parasites (insects, mites or fungi). ), sometimes irreversibly.

In addition, the cultivation of plants generally requires the use of fertilizers that stimulate their growth. Fertilizers are root-based, that is, they are applied to the soil and absorbed by the roots, or foliar.

Unlike pesticides, fertilizers are applied early in plant growth, and therefore at generally different times than pesticides.

This leads to applying pesticides and fertilizers separately, which can be a source of physical stress in addition to being very time-consuming.

DESCRIPTION OF THE INVENTION

An object of the invention is to propose a process for treating a plant which makes it possible to overcome the drawbacks described above.

The invention is particularly aimed at providing a process for treating a plant making it possible to prevent the latter from being degraded by parasites (insects, mites or fungi in particular).

To this end, the invention proposes a process for the preventive treatment of a plant to prevent infestation by a parasite, consisting in applying to said plant a composition comprising a vegetable oil before the appearance of the infestation.

By “parasite” is meant any animal species likely to be harmful to the development of the plant, which usually degrades its structure, in particular but not exclusively insects (the composition is then an insecticide). Examples of pests, often referred to as "pests", include aphids, scale insects, thrips whiteflies. The term "parasite" also includes mites (also called spider mites) which can infest plants in a similar way, as well as fungi, the latter developing on the plant, such as rose black spot disease.

The treatment is carried out preventively, in that the composition is applied before the appearance of the infestation, that is to say before the appearance of the parasites on the plant or of their symptoms (first individuals for the insects or mites, first colored spots for mushrooms for example). Contrary to a curative application, any prolonged contact between the parasites and the plant is avoided, which avoids the degradation of the plant usually caused by the latter.

However, the composition can be applied to the plant after the appearance of the infestation, when the parasites or the fungi are already present on the plant. The composition will then have a curative effect on the parasites already present, as well as a preventive effect which limits the development of the infestation, or at least prevents the appearance of a new infestation, and therefore the appearance of new parasites or mushrooms on the vegetable.

The composition is preferably applied foliarly, that is to say it is applied directly to the aerial parts of the plant, in particular the foliage, the stems and/or the flower buds. It can be applied for example using a pressure sprayer, or a ready-to-use spray type device, etc.

The composition is intended for the treatment of any type of plant, and in particular ornamental plants, and vegetable and fruit crops.

The composition is preferably applied during the vegetative period of the plant. The vegetative period, also known as the growing season, corresponds to the part of the calendar year during which the local weather conditions (i.e. precipitation and temperature) allow normal growth of the plant. The vegetative period obviously depends on the nature of the plant in question.

Vegetable oil has a barrier effect, in the sense that it acts physically by forming a barrier between the plant and the parasite (preventive effect) or on the parasite by covering it and suffocating it (curative action). It does not have an insecticidal, acaricidal, or chemical fungicidal (chemical action) effect.

The vegetable oil is preferably chosen from castor oil, soybean oil, or a mixture thereof. These oils have the advantage of being readily available commercially and at low cost. In addition, these oils have little or no phytotoxic effect when used on the plant, an effect sometimes being observed with certain oily compositions.

Preferably, the composition does not include rapeseed oil, sunflower oil or paraffin oil. These oils are indeed recognized from a regulatory point of view as phytopharmaceutical active ingredients, and require approval to be used in the fields of agriculture and horticulture.

With regard to parasites, the composition is particularly effective in protecting against rust disease ( Phragmidium mucronatum ), black spot disease ( Diplocarpon rosae or Marssonina rosae ), powdery mildew ( Erysiphe sp. ), or even boxwood diseases ( Cylindrocladium buxicola, Volutella buxi ), and to control populations of aphids (for example Macrosiphum rosae ), mealybugs, mites, thrips, or even whiteflies.

The composition may further comprise at least one nutrient.

In general, the home gardener is used to regularly applying fertilizer or adding nutrients to his plants at the start of the season.

The amateur gardener applies the treatment products when the infestation is well established, due to a lack of technical information.

Therefore, the combination of a nutrient and a vegetable oil, for the implementation of the preventive treatment according to the invention, has the advantage that the composition is applied upstream of the infestation in accordance with the usual of the gardener regarding the fertilizer described above.

The nutrient provides some of the nutrients necessary for the development of the plant, and improves the yield and quality of crops. Thus, the vegetable is supplemented by the nutritive element, and treated preventively against the parasites by the vegetable oil. A growth effect of the plant is therefore associated with an effect of preventive protection of the plant against parasites. These two effects are obtained by applying a single composition, instead of applying a pesticide and applying a fertilizer separately, thus reducing the physical constraints in addition to reducing the time required. in carrying out these tasks.

The presence of a nutrient fits perfectly with the preventive nature of the process and the regular application over time of the composition, since, generally in agriculture and horticulture, the nutrient is applied from the start of the growth of the plant and the application is renewed regularly. The user can therefore use the composition of the invention as if he were using a fertilizer, while also benefiting from the protective effect of the vegetable oil.

The nutrient preferably comprises at least one mineral fertilizer. It is more preferably a nitrogen-based fertilizer which has the advantage of being effective and stable.

Preferably, the composition comprises the following oil/nutrient couples, which all lead to an effective treatment, without phytotoxicity: Castor oil/nitrogen and soybean oil/nitrogen.

Preferably, the vegetable oil/nutrient element mass ratio is between 1:1 and 100:1, preferably between 5:1 and 12:1 for a mineral nutrient element, or between 30:1 and 40:1 for a mineral element. organic nutrient. These ratios make it possible to obtain a satisfactory growth stimulation effect while ensuring good coverage of the aerial parts of the plant and therefore optimal treatment.

The nutrient may include one or more major nutrients and/or one or more minor nutrients.

The major nutrients are the nutrients that the plant needs in large quantities. Nitrogen, phosphorus, and/or potassium may be present in the composition, for example, nitrogen being preferred.

The minor nutrients are the nutrients that the plant needs in smaller quantities relative to the major nutrients. May be present in the composition, for example, iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), calcium (Ca) and/or molybdenum (Mo).

Surprisingly, no antagonistic effect is observed between the nutritive element and the vegetable oil, even though the first promotes the growth of the plant and therefore the appearance of young shoots which attract the parasites, while the second fight against them. The composition allows the plant to develop while effectively preventing the appearance and proliferation of parasites.

In addition, the composition is not phytotoxic, so the leaves are not burned. There is no aggravating effect of the nutrient, on the burning effect sometimes observed when bringing certain vegetable oils into contact with certain species of plants.

According to a preferred embodiment, the composition comprises calcium nitrate. Calcium is a minor nutrient which stiffens the cell walls of plant cells when the composition is applied. In doing so, it makes the plant more resistant to external aggressions, and avoids any deficiency of the plant in calcium which is an essential element for its growth. Calcium nitrate plays a role both in the growth of the plant (calcium useful for the development of the plant) and in the antiparasitic effect (reinforcement of the cell wall).

The calcium nitrate may be present in the composition with one or more nutrients as described previously, or without the latter. Surprisingly, no antagonistic effect is observed between the nutrient and calcium nitrate, even though the first promotes the growth of the plant, while the second stiffens the cells and would therefore tend to reduce growth. of the vegetable. No growth retardation (growth dwarfism) was observed on the plants treated with the composition of the invention, which indicates that, contrary to what a person skilled in the art could have supposed, the use of nitrate of calcium in the composition does not reduce plant growth.

Preferably, the calcium nitrate/vegetable oil mass ratio in the composition is between 1:35 and 1:70, preferably between 1:55 and 1:59. These ratios make it possible to obtain an effect of resistance to external attack. satisfactory while ensuring good coverage of the foliage of the plant.

According to a preferred embodiment, the composition comprises:

• from 0.5% to 3% by weight, preferably from 1.5% to 1.9% by weight, of vegetable oil,
• from 0.01% to 1% by weight, preferably from 0.03% to 0.5% by weight, more preferably from 0.15% to 0.3% by weight, of nutrient,
• from 90% to 99.4% by weight, preferably from 96% to 98% by weight, of water.

The composition optionally comprises co-formulants to improve the application, the preservation or the stability of the formula, in particular surfactants and preservatives and stabilizers for example.

According to a preferred embodiment, the composition is obtained by dilution in water of a concentrate comprising:

• from 20% to 90% by weight, preferably from 50% to 70% by weight, of vegetable oil,
• from 0.1% to 10% by weight, preferably from 1.5% to 5% by weight, of nutrient.

The rest of the composition comprises water and, preferably, the co-formulants before applying it to the vegetation to be treated. The concentrate is previously stored and preserved. It is diluted by the user with water just before treating the vegetation, in order to obtain the composition ready to be applied to the vegetation.

Alternatively, the composition may be in a “ready to use” formulation, or “Ready To Use” in English (acronym RTU). The dilution of the concentrate comprising the vegetable oil and the nutritive element is carried out upstream of the treatment, so that the user only has to treat the vegetation without the need to carry out the mixture: the product that puts in work the user does not require any dilution prior to its use. In practice, the composition is directly prepared and stored in a container suitable for this purpose for a determined time, for example a container intended for sale. When he wishes to treat vegetation, the user can therefore directly use the RTU mixture.

Preferably, the concentrate is present in the composition in an amount between 1 mL and 300 mL, preferably between 10 mL and 100 mL, and more preferably between 20 mL and 50 mL, per liter of composition, the complement to 1 liter being water. The composition of course refers to the final composition resulting from the dilution of the concentrate with water.

As regards the treatment methods, the composition is preferably applied at least one month before the expected appearance of the infestation, and at a rate of between every day and every 21 days, preferably between every 7 days and 18 days, more preferably between every 10 days and 16 days, and even more preferably between every 13 days and 15 days. Such a rate makes it possible to obtain a preventive effect with regard to satisfactory parasites and/or fungi, and, when the composition comprises a nutritive element, this rate ensures in parallel a regular supply and sufficiently spaced out in time of the nutrient to optimally promote plant growth.

Furthermore, the composition is preferably applied at a rate of 100 L/ha (Liters per hectare) to 3000 L/ha, preferably from 300 L/ha to 2000 L/ha, more preferably from 600 L/ha to 1500 L/ha, and even more preferably from 800 L/ha to 1200 L/ha.

The invention also relates to a composition for implementing the process for the preventive treatment of a plant as described above.

The composition includes:

• vegetable oil,
• a nutrient, preferably comprising an inorganic fertilizer,

wherein the vegetable oil/nutrient mass ratio is between 1:1 and 100:1, preferably between 5:1 and 12:1 for a mineral nutrient, or between 30:1 and 40:1 for a nutrient organic.

DESCRIPTION OF FIGURES

Other advantages and characteristics of the invention will appear on reading the following description given by way of illustrative and non-limiting example, with reference to the following appended figures:

is a graph that depicts the efficacy over time of various antiparasitic/antifungal compositions for the treatment of black spot disease;

is a graph which represents the efficacy over time of various antiparasitic/antifungal compositions for the treatment of rust;

is a graph which represents the efficacy over time of various antiparasitic/antifungal compositions against scale insects.

EXAMPLES OF REALIZATION OF THE INVENTION

Several compositions were prepared and then applied to different species of plants, to treat them against black spot disease, rust, and scale insects.

To do this, the concentrated compositions are first prepared, each comprising at least one vegetable oil. Each of these compositions is mixed with an aqueous phase in order to obtain the compositions numbered from C1 to C4 in the following table 1.

To prepare the compositions, 30 mL of concentrate is diluted in 970 mL of water.

The compositions are applied to the level of the leaves of the plant, on the top and on the underside of the leaves, up to the point of run-off, namely until the moment when any additional application of product drips from the leaves and falls to the ground.

The compositions are applied every two weeks, from the beginning of the season (March) until the end of the season (September).

The effectiveness of these compositions is compared with untreated vegetation (test N) and with several commercial insecticide/fungicide products: Rozen-Pilzfrei Saprol® (black spot and rust / 9.72g/L triticonazole / noted RPS in the figures) marketed in particular by the company Evergreen Garden Care GmbH, Rapidinsect® (cochineals / rapeseed oil 700g/L and pyrethrum 7g/L / noted RI in the figures) marketed in particular by the company Evergreen Garden Care France SAS, and Naturen Eradibug® (cochineals / Rapeseed oil 777g/L / noted NE in the figures) marketed in particular by the company Evergreen Garden Care France SAS. The untreated plants are denoted N in the figures.

Table 1 indicates the nature of the constituents of the various compositions, as well as the quantity of composition applied per hectare.

In FIGS. 1 and 2, the intensity (“Intensity” in English) of the black spot disease and the intensity of the rust are indicated on the ordinate, and denoted Int (%), as a function of time on the abscissa. On the , the ordinate AP (“Average Population”) corresponds to the average population of scale insects per plant, as a function of the days, denoted D (“Days”), on the abscissa.

On the graphs of FIGS. 1 and 2, it is observed that compositions C1 to C4, used as a preventive measure (before the appearance of the disease), strongly limit the development of black spot and rust over time, in addition to delay their onset. The effectiveness of compositions C1 to C4 is comparable to that of Rozen-Pilzfrei Saprol® for black spot, and superior to that of Rozen-Pilzfrei Saprol® for rust.

On the graph of , it is observed that the compositions C1 to C4, used curatively (when the disease is already present), eliminate mealybugs effectively, thus treating the plant. The effectiveness of compositions C1 to C4 against scale insects is comparable to that of Rapidinsect® and Naturen Eradibug®.

These examples thus confirm that the treatment method according to the invention aims to treat a plant preventively, and also makes it possible to treat the plant curatively, that is to say to treat a disease already present.

Therefore, the application of a composition according to the invention makes it possible to prevent, limit, and delay a disease to come, while treating a disease possibly already present during the application.

Claims (17)

Process for the preventive treatment of a plant to prevent infestation by a parasite, consisting in applying to the said plant a composition comprising a vegetable oil before the appearance of the infestation. A method according to claim 1, wherein the pests include aphids, mealybugs, whiteflies, spider mites, thrips, black spot, rust, powdery mildew or leaf spot fungi. boxwood. A method according to claim 1 or claim 2, wherein the composition is applied during the vegetative period of the plant. Process according to any one of the preceding claims, in which the application is foliar, that is to say directly on an aerial part of the plant. Process according to any one of the preceding claims, in which the vegetable oil is chosen from castor oil, soybean oil, or a mixture thereof. A method according to any preceding claim, wherein the composition further comprises at least one nutrient. A method according to claim 6, wherein the nutrient comprises a major nutrient, preferably nitrogen. Process according to Claim 6 or Claim 7, in which the vegetable oil/nutrient element mass ratio is between 1: 1 and 100: 1, preferably between 5: 1 and 12: 1 for an inorganic nutrient element, or between 30 : 1 and 40 : 1 for an organic nutrient. A method according to any of claims 6 to 8, wherein the nutrient comprises a minor nutrient, preferably calcium. A method according to any preceding claim, wherein the composition also includes calcium nitrate. Process according to Claim 10, in which the mass ratio of calcium nitrate/vegetable oil in the composition is between 1: 35 and 1: 70, preferably between 1: 55 and 1: 59. A method according to any of claims 6 to 11, wherein the composition comprises:
- from 0.5% to 3% by weight, preferably from 1.5% to 1.9% by weight, of vegetable oil,
- from 0.01% to 1% by weight, preferably from 0.03% to 0.5% by weight, more preferably from 0.15% to 0.3% by weight, of nutrient,
- from 90% to 99.4% by weight, preferably from 96% to 98% by weight, of water. Process according to any one of Claims 6 to 12, in which the composition is obtained by diluting in water a concentrate comprising:
- from 20% to 90% by weight, preferably from 50% to 70% by weight, of vegetable oil,
- from 0.1% to 10% by weight, preferably from 1.5% to 5% by weight, of nutrient. Process according to Claim 13, in which the concentrate is present in the composition in an amount of between 1 mL and 300 mL, preferably between 10 mL and 100 mL, and more preferably between 20 mL and 50 mL, per liter of composition, the complement to 1 liter consisting of water. Method according to any one of the preceding claims, in which the composition is applied at least one month before the appearance of the infestation, and at a rate of between every day and every 21 days, preferably between every 7 days and 18 days, more preferably between every 10 days and 16 days, and even more preferably between every 13 days and 15 days. A method according to any preceding claim, wherein the composition is applied at a rate of 100 L/ha to 3000 L/ha, preferably 300 L/ha to 2000 L/ha, more preferably 600 L/ha. ha to 1500 L/ha, and even more preferably from 800 L/ha to 1200 L/ha. Composition for the implementation of a method for the preventive treatment of a plant according to any one of the preceding claims in combination with Claim 6, the said composition comprising:
- a vegetable oil,
- a nutrient,
in which the vegetable oil/nutrient element mass ratio is between 1:1 and 100:1, preferably:
- between 5:1 and 12:1 for a mineral nutrient,
- between 30:1 and 40:1 for an organic nutrient.