Use of insect puparia for increasing plant growth

Abstract

The present invention relates to the use of a composition comprising (i) holometabolous insect puparia, preferably Hermetia illucens, (ii) whole dead flies or fragments thereof, or (iii) a mixture of same, for accelerating plant growth and / or for increasing crop yield. The invention also relates to a plant seed coated with such a composition. The invention further relates to a method of coating a seed and a method of cultivating a plant using said composition.

Description

[0001] DESCRIPTION

[0002] TITLE: Use of insect puparia to increase plant growth

[0003] The present invention relates to the use of a composition comprising (i) holometabolous insect puparia, (ii) whole dead flies or fragments thereof, or (iii) a mixture thereof, for accelerating plant growth and / or increasing crop yield. It also relates to a plant seed coated with such a composition. Finally, it relates to a seed coating method and a method for accelerating plant growth and / or increasing crop yield, using this composition.

[0004] The search for new strategies to maintain or increase the productivity of agricultural systems, while reducing the use of agricultural inputs, is of constant interest.

[0005] Among the alternatives to chemical compounds, chitin and its derivatives, such as chitosan, are known as biopesticides or for stimulating the natural defenses of plants. These products are generally applied by foliar application or by mixing into the soil.

[0006] However, such products must first be extracted, processed and / or purified, which is complex and time-consuming to implement.

[0007] Furthermore, rapid crop initiation is critical to crop success, as it ensures proper establishment. Proper establishment limits the risk of destruction by pests or harsh weather conditions and accelerates the plant's initial growth. This generally results in better yields and / or greater plant resilience to external attacks.

[0008] There is therefore a need for alternatives to chemical inputs that are easy to apply and effective. In particular, there is a need for bio-sourced alternatives, particularly recycled ones. In particular, there is a need for a bio-sourced alternative that is easy and quick to obtain and less expensive. Said alternative is in particular a means of recovering a co-product (i.e. waste) generated in an industry. The Applicant has now discovered, as shown in the examples, that coating cereal seeds, particularly corn, with ground black soldier fly puparia (Hermetia illucens, or BSF), increases the growth of the aerial biomass of corn a few days after sowing, compared to an untreated control. In particular, these effects are particularly marked for low doses (i.e. greater effect for lower doses).

[0009] Such puparium ground material is very easy and quick to obtain, bio-sourced, and allows the recycling of BSF breeding co-products.

[0010] The present invention therefore relates to the use of a composition comprising (i) puparia of holometabolous insect, preferably of Hermetia illucens, (ii) flies, preferably Hermetia illucens, dead whole or their fragments, or (iii) one of their mixtures, to accelerate the growth of plants and / or to increase the crop yield.

[0011] The present invention also relates to a plant seed coated with a composition comprising (i) puparia of holometabolous insect, preferably Hermetia illucens, (ii) flies, preferably Hermetia illucens, dead whole or their fragments, or (iii) one of their mixtures.

[0012] The composition comprising (i) puparia of holometabolous insect, preferably of Hermetia illucens, (ii) flies, preferably Hermetia illucens, dead whole or their fragments, or (iii) one of their mixtures, is also called "composition according to the invention".

[0013] The term "plants" preferably means cereals or vegetable plants. Preferably, the cereals are chosen from corn, wheat, rice, barley, millets (including sorghum), oats and rye. Preferably, the cereals are chosen from corn and wheat. Preferably, the vegetable plants are chosen from salads such as lettuce, potatoes, green beans, cucumbers, spinach and carrots.

[0014] By "seed" we mean the grain.

[0015] By "acceleration of plant growth" is meant an increase in aerial biomass (i.e. leaves, stems and flowers) of at least 10%, preferably at least 15%, preferably at least 20%, preferably at least 22%, compared to the same species of plant not treated with the composition according to the invention, after at least 7 days of cultivation.

[0016] By "increasing the crop yield" is meant a significant increase in this yield. This yield can be measured by harvesting the biomass. Preferably, by "increasing the crop yield" is meant that the above-ground biomass (i.e. leaves, stems and flowers) of the crop is increased by at least 10%, preferably at least 15%, preferably at least 20%, preferably at least 22%, compared to the same crop not treated with the composition according to the invention, after at least 7 days of cultivation.

[0017] The composition according to the invention comprises (i) holometabolous insect puparia, (ii) whole dead flies or fragments thereof, or (iii) one of their mixtures.

[0018] According to a first embodiment, the composition according to the invention comprises (i) holometabolous insect puparia. Holometabola are a superorder of insects. The development of holometabolous insects is characterized by a complete metamorphosis, i.e. an egg, then a larva (which differs greatly from adults), then a nymph, and finally an imago (adult). Preferably, the holometabolous insect is chosen from Diptera, preferably from Brachycera, preferably from Stratiomyidae.

[0019] Preferably, the holometabolous insect is the black soldier fly (Hermetia illucens, or BSF, for black soldier fly).

[0020] The black soldier fly (Hermetia illucens, or BSF) is a fly of the order Diptera, family Stratiomyidae. The life cycle of this insect is composed of 9 stages: the egg, six larval stages, the pupa and the adult.

[0021] The cycle begins with an egg, oval in shape, about 1 mm long and pale yellow or creamy white in color. This egg hatches after about 4 days, producing a larva.

[0022] Newly hatched larvae measure approximately 1.8 mm. At the end of their growth, they are broad and oval and can reach 27 mm long and 6 mm wide. The larvae pass through six larval stages (L1 to L6), which can last from 15 days to 5 months (depending on conditions): the larval stages are differentiated by the size of the larvae, their color (which darkens as the stages progress) and the development of the setae. Between each larval stage, a moult occurs; the larva leaves the integument (exuvia) which has become too small, this rejection is called exuviation. The sixth larval stage is the prepupa stage. During this stage, the larvae turn reddish brown.

[0023] Then the prepupae become immobile and begin their metamorphosis; we then speak of pupae. The pupa differs from the other two nymphal forms in that metamorphosis takes place during a process comprising all the stages of molting except exuviation. The individual is then completely enclosed in the last larval exuvia, called the puparium, and completely immobile. This puparium is completely rigid due to quinone tanning of the free amine function of the structural proteins, which makes the exocuticle harder. The procuticle (i.e. exo- and endocuticles) of the puparium being detached from the future imago (adult), the whole takes on an ovoid shape.

[0024] After two to three weeks in the pupal stage, adults emerge (emergence of the imago) and reproduce when they are sexually mature (2 days after emergence). Upon emergence, the imago extracts itself from the puparium.

[0025] The cuticle, or exoskeleton, is the outer layer secreted by the epidermis of insects, here Hermetia illucens. It is generally made up of three layers:

[0026] -the epicuticle, which is the thinnest and outermost layer of the cuticle (less than 4 pm); this layer is impermeable to water and contains a layer of waterproofing wax, as well as proteins and chitin, in smaller quantities;

[0027] -the exocuticle, which is the intermediate layer of the cuticle; it is composed mainly of hardened proteins, the tannins, which are responsible for the rigidity of the cuticle, chitin and possibly melanin; and

[0028] - the endocuticle, which is a thin, flexible layer made up of a mixture of proteins and chitin.

[0029] The exo- and endocuticles form the procuticle.

[0030] Preferably, according to a first embodiment, the composition according to the invention comprises (i) puparia of holometabolous insect, preferably of Hermetia illucens.

[0031] By puparium of a holometabolous insect, preferably of Hermetia illucens, is meant an empty puparium, i.e. after the imago has emerged. These pupariums are recovered after the emergence of the adult flies; typically they are co-products of BSF rearing. The puparium is the envelope of the pupa. This envelope is rigid. The puparium is different from the larval exuviae, which are the exuviae of the first six larval stages. The puparia of Hermetia illucens according to the invention generally have the following profile, in dry matter weight relative to the total weight of puparium:

[0032] - a content of less than or equal to 25% by weight of chitin;

[0033] - a content of at least 5% by weight of total fat.

[0034] Furthermore, the puparia of Hermetia illucens according to the invention generally contain manganese in a content of at least 200 ppm, preferably at least 400 ppm (on dry matter) (puparia of Hermetia illucens according to the invention). This manganese concentration is much higher than the larval exuviae. Indeed, for comparison, the larval exuviae typically comprise manganese in a content of less than 110 ppm on dry matter. This manganese, in association with the other constituents of the puparia, seems to play a role in the observed increase in plant growth.

[0035] Preferably, the pupariums of Hermetia illucens according to the invention have the following profile, in dry matter:

[0036] - from 5% to 25% by weight of chitin relative to the total weight of puparium;

[0037] - from 5% to 30% by weight of total fat relative to the total weight of puparium; and

[0038] - from 200 ppm to 2000 ppm of manganese.

[0039] Preferably, the pupariums of Hermetia illucens according to the invention have the following profile, in dry matter:

[0040] - from 10% to 25% by weight of chitin relative to the total weight of puparium;

[0041] - from 5% to 30% by weight, preferably from 5% to 20% by weight, of total fat relative to the total weight of puparium; and

[0042] - from 200 ppm to 2000 ppm of manganese, preferably from 400 ppm to 1500 ppm, preferably from 600 ppm to 1000 ppm.

[0043] The advantage is partly in the simplicity of use (no pre-processing or extraction step is necessary), and partly in the interesting effects obtained.

[0044] The composition according to the invention comprises puparia of a holometabolous insect, preferably of Hermetia illucens, as active ingredient. Preferably, this composition is preferably exclusively composed of puparia of a holometabolous insect, preferably of Hermetia illucens. The composition comprising puparia of a holometabolous insect, preferably of Hermetia illucens according to the invention, is preferably a powder, or a paste. Indeed, preferably, the puparia of a holometabolous insect, preferably of Hermetia illucens, are used in powder form, or in paste form. For example, they can be obtained by grinding, for example in a mortar and pestle; the composition is then a ground puparia. Such a powder (or ground material) of holometabolous insect puparia, preferably of Hermetia illucens according to the invention, differs from commercial products by its composition, i.e.it contains all the constituents of the puparia, and not just chitin. For example, such a powder (or ground material) of puparia of Hermetia illucens according to the invention comprises fats. Moreover, chitin is not the majority in the puparia powder. Indeed, the chitin content in such a powder is typically less than 25% by weight in dry matter, preferably less than 24% by weight in dry matter.

[0045] According to a second embodiment, the composition according to the invention comprises (ii) whole dead flies or their fragments. Preferably, the whole dead flies or their fragments are chosen from Brachycera, preferably from Stratiomyidae. Preferably, the whole dead flies or their fragments are dead black soldier flies (Hermetia illucens) or their fragments.

[0046] These dead flies, or their fragments, are typically present as by-products of BSF rearing. They are present as such because not all flies survive past adult emergence. They can be collected as is.

[0047] The dead Hermetia illucens flies or their fragments according to the invention generally have the following profile, in dry matter weight relative to the total weight of dead flies:

[0048] - a content of less than or equal to 10% by weight of chitin;

[0049] - a content of at least 25% by weight of total fat.

[0050] Furthermore, the dead flies according to the invention generally contain manganese in a content of less than 50 ppm (on dry matter) (dead flies Hermetia illucens or their fragments according to the invention).

[0051] Preferably, the dead Hermetia illucens flies or their fragments according to the invention have the following profile, in dry matter: - a content of less than or equal to 7% by weight of chitin relative to the total weight of dead flies;

[0052] - from 27% to 40% by weight of total fat relative to the total weight of dead flies; and

[0053] - from 5 ppm to 40 ppm of manganese.

[0054] According to a third embodiment, the composition according to the invention comprises (iii) a mixture of puparia of holometabolous insect, preferably of Hermetia illucens, and whole dead flies or their fragments.

[0055] Preferably, such a mixture comprises the puparia of a holometabolous insect, preferably of Hermetia illucens, having the profile described above (ingredient (i)).

[0056] Preferably, such a mixture comprises whole dead flies or their fragments having the profile described above (ingredient (ii)).

[0057] The mixture can be made in any proportion of puparia to whole dead flies or their fragments.

[0058] Preferably, the composition according to the invention comprises a mixture (iii) of Hermetia illucens puparia, and whole dead Hermetia illucens flies or their fragments. Such a mixture is a co-product of BSF breeding.

[0059] The composition according to the invention can be applied by any means. In particular, it can be applied directly to the growing substrate, such as the soil (earth), for example by irrigation; or applied to the plants, for example to the roots, to the aerial parts such as the leaves, flowers and / or stems; or applied to the seeds, for example by coating. Preferably, the composition according to the invention is applied directly to the soil, preferably by irrigation; or applied to the seeds, preferably by coating.

[0060] By "substrate" is meant any substrate suitable for growing plants, preferably chosen from soil, potting soil, peat, sand and their mixtures.

[0061] The invention also relates to a method for coating a seed, comprising the following steps: a) preparation of a composition comprising (i) puparia of a holometabolous insect, preferably of Hermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof. Preferably, the composition is a powder of puparia of Hermetia illucens, for example obtained by grinding; and b) coating at least one seed with the composition obtained in step a).

[0062] Step a) of preparing the composition, preferably the powder, of puparia of a holometabolous insect, preferably of Hermetia illucens, is simple. It is carried out, for example, by grinding the puparia, for example in a mortar and pestle.

[0063] The puparia are notably recovered in the form of fly breeding waste (BSF breeding co-products).

[0064] The composition may also be obtained in step a) by grinding whole dead flies or their fragments. It may also be obtained by grinding a mixture of puparia and whole dead flies or their fragments.

[0065] Step b) comprises coating at least one seed with the composition obtained in step a). This coating step is preferably carried out by simply mixing the powder obtained in a), diluted in water, with at least one seed, then optionally drying.

[0066] Preferably, this coating step is carried out as follows: the powder of puparia of a holometabolous insect, preferably of Hermetia illucens, is mixed with water to obtain a solution. Preferably, the weight ratio (puparia powder): water is between 1:10 and 1:7;

[0067] - the supernatant is then taken, which is called the “basic solution”;

[0068] - we dilute this basic solution; we prepare a mixture of basic solution diluted with water;

[0069] - the basic solution diluted with water is applied to at least one seed; and possibly left to dry.

[0070] Preferably, the coating of step b) is carried out in a weight ratio (puparia in active material): seeds of between 10 -4 and 10 -10 , preferably between 2x10 -4 and 2x10 -9 .

[0071] Indeed, with such a ratio, the acceleration of plant growth is significantly improved, as shown in examples.

[0072] At the end of step b), a coated seed according to the invention is obtained. The invention also relates to a method for growing a plant on a substrate, comprising the following steps: a) preparation of a composition comprising (i) puparia of a holometabolous insect, preferably diHermetia illucens, (ii) whole dead flies or fragments thereof, or (iii) a mixture thereof, preferably a powder of diHermetia illucens puparia, for example by grinding; and b') application of the composition obtained in step a) to the substrate, or to the plant, for example to its roots or to its aerial parts such as leaves, flowers and / or stems, or to at least one seed, for example by coating.

[0073] Step a) of the process of growing a plant is identical to that described above. This process allows for an acceleration of the growth of the plant and / or an increase in the crop yield of this plant.

[0074] Step b') comprises applying the composition obtained in step a) directly to the substrate, or to the plant, for example to its roots or to its aerial parts such as the leaves, flowers and / or stems, or to at least one seed, for example by coating. Preferably, the composition of step a) is applied directly to the substrate such as the soil, preferably by irrigation; or applied to the seeds, preferably by coating. Preferably, the application of step b') is carried out on the substrate by irrigation or on at least one seed by coating.

[0075] When step b') is a coating of at least one seed with the composition obtained in step a), steps b) and b') are identical. Thus, the characteristics described above for step b) also apply to step b'). Preferably, in this case, the cultivation method comprises the following steps c) and d): c) preparation of the sowing with the seed of step b); and d) cultivation of the sowing of step c).

[0076] Step c) includes the preparation of sowing with the coated seed, obtained in step b').

[0077] Sowing preparation is carried out in a conventional manner, for example by sowing in the ground, then covering with a layer of soil, possibly moist.

[0078] Finally, step d) includes the cultivation of the seedling. Cultivation is also conventional, and is carried out under temperature and watering conditions adapted to each plant. The following examples are given for illustrative purposes.

[0079] Example 1: Measurement of aerial biomass in corn plants treated with puparia according to the invention

[0080] Preparation of puparium samples according to the invention

[0081] Black soldier fly puparia (Hermetia illucens) were collected and ground in a mortar and pestle to obtain a powder. A powder of Hermetia illucens puparia according to the invention is obtained.

[0082] 2 g of this powder are mixed in 15 ml of water to obtain a solution. The supernatant, which is called the “base solution”, is then taken.

[0083] The following diluted samples are prepared:

[0084] Witness = water

[0085] Sample 1 = basic solution diluted to 10 1 (300 ft of base solution + 2700 ft of water)

[0086] Sample 2 = basic solution diluted to 10 -2(300 pl of sample 1 + 2700 pl of water) Sample 3 = basic solution diluted to 10 -3 (300 pl of sample 2 + 2700 pl of water) Sample 4 = basic solution diluted to 10 -4 (300 pl of sample 3 + 2700 pl of water) Sample 5 = basic solution diluted to 10 -5 (300 pl of sample 4 + 2700 pl of water).

[0087] Seed preparation

[0088] For each sample, a mixture of 3.8 ml of water and 220 µl of sample ("slurry") is then prepared. Stir for 15 seconds.

[0089] Then 1.8 ml of the mixture obtained (porridge) is applied to 90.5 g of corn seeds (genotype KXC387 from KWS) placed in a plastic bag: precisely, the porridge is poured into the bag, the seeds are added, and the closed bag filled with air is stirred for 1 minute.

[0090] Preparing the seedlings

[0091] We then prepare the seedlings in a tray of soil:

[0092] The trays are prepared with 1.5 kg of moist soil.

[0093] Sow with 10 rows of 10 seeds. Add a 750g bed of moist soil over the seeds.

[0094] It is closed with a lid and incubated at 20°C during the day and 15°C at night, with a 16-hour photoperiod. The starting point is JO.

[0095] Measurements and observations made

[0096] The aerial biomass is measured by taking images using the Canopeo tool on 3 different dates: D7, D8 and D9.

[0097] Results

[0098] The results are as follows:

[0099] [Table 1]

[0100] The statistical method used is the Anova method with a threshold of 10%.

[0101] A significant improvement in aerial biomass was observed a few days after sowing, a sign of a better start to growth: up to +22% vs. Control.

[0102] A dose effect is also clearly visible: we observe a greater effect for reduced doses (i.e. dilution 10 5 ).

[0103] Example 2: Measurement of aerial biomass in corn plants treated with puparia according to the invention

[0104] Preparation of puparium samples according to the invention Black soldier fly (Hermetia illucens) puparia were collected and ground in a mortar and pestle to obtain a powder. A powder of Hermetia illucens puparia according to the invention is obtained.

[0105] 5 g of this powder is mixed in 50 ml of water to obtain a solution. The supernatant, which is called the “base solution”, is then taken.

[0106] The following diluted samples are prepared:

[0107] Witness = water

[0108] Sample 1 = basic solution diluted to 10 -1 (300 ft of base solution + 2700 ft of water)

[0109] Sample 2 = basic solution diluted to 10 -2 (300 pl of sample 1 + 2700 pl of water) Sample 3 = basic solution diluted to 10 -3 (300 pl of sample 2 + 2700 pl of water) Sample 4 = basic solution diluted to 10 -4 (300 pl of sample 3 + 2700 pl of water) Sample 5 = basic solution diluted to 10 -5 (300 pl of sample 4 + 2700 pl of water)

[0110] Seed preparation

[0111] For each sample, a mixture of 450 ml of water and 50 ml of sample ("slurry") is then prepared. Stir for 15 seconds.

[0112] Then 2.8 ml of the mixture obtained (porridge) is applied to 140 g of corn seeds (genotype LS201100171 of RAGT) placed in a plastic bag: precisely, the porridge is poured into the bag, the seeds are added, and the closed bag filled with air is stirred for 1 minute.

[0113] Preparing the seedlings

[0114] We then prepare the seedlings in a tray of soil:

[0115] The trays are prepared with 1.5 kg of moist soil.

[0116] We sow with 10 lines of 10 seeds.

[0117] A 750g bed of moist soil is added over the seeds.

[0118] It is closed with a lid and incubated at 20°C during the day and 15°C at night, with a 16-hour photoperiod. The starting point is D0.

[0119] Measurements and observations made The aerial biomass is measured, by taking images using the Canopeo tool, on 2 different dates: D7 and D8.

[0120] Results

[0121] The results are as follows:

[0122] [Table 2]

[0123] At D7, we observe a significant improvement in aerial biomass (only for the lowest doses, i.e. 10 -6 ), and a decrease in growth for the other doses (vs. Control).

[0124] At D8, we observed an improvement in the growth of aerial biomass for all modalities, with better performance for the lowest doses: +15% at 1 (T 6 .

[0125] Example 3: Measurement of aerial biomass in lettuce plants treated with pupariums according to the invention

[0126] Preparation of puparium samples according to the invention

[0127] Black soldier fly (Hermetia illucens) puparia were collected and ground in a mortar and pestle to obtain a powder. A powder of Hermetia illucens puparia according to the invention is obtained. 5 g of this powder is mixed in 50 ml of water to obtain a solution. The supernatant is then collected, which is called the "base solution".

[0128] The following diluted samples are prepared:

[0129] Witness = water

[0130] Sample 2 = basic solution diluted to 10 -2(50 ml of basic solution is mixed with 450 ml of water)

[0131] Sample 3 = basic solution diluted to 10 -3 (50 ml sample 2 + 450 ml water)

[0132] Sample 4 = basic solution diluted to 10 -4 (50 ml sample 3 + 450 ml water)

[0133] Sample 5 = basic solution diluted to 10 -5 (50 ml sample 4 + 450 ml water)

[0134] Sample 6 = basic solution diluted to 10 -6 (50 ml of sample 5 + 450 ml of water).

[0135] Preparing the seedlings

[0136] We then prepare the seedlings in a mini-greenhouse:

[0137] 72 pots are used, and 3 lettuce seeds per pot are planted in sieved potting soil.

[0138] Incubate at 20°C for 22 days.

[0139] Then, 100 ml of one of the samples is poured into the soil using a peristaltic pump for each pot. This corresponds to treatment no. 1 (D0). This treatment is repeated on D1 (treatment no. 2), D17 (treatment no. 3) and D28 (treatment no. 4).

[0140] Measurements and observations made

[0141] The aerial biomass is measured, by taking images using the Canopeo tool, at D50 (but also during the experiment).

[0142] In addition, at D50, the aerial and root biomass is collected and incubated at 80°C for drying. 2 days later, this dried biomass is weighed.

[0143] Results

[0144] The results are as follows:

[0145] [Table 3]

[0146] There was a significant improvement in aerial biomass (fresh and dry), therefore an improvement in plant growth for all doses.

[0147] These results are visible throughout the plant's growth.

[0148] There is no significant effect on germination capacity.

[0149] Example 4: Measurement of aerial biomass in lettuce plants treated with puparia or dead flies according to the invention

[0150] The purpose of this research program is to evaluate the fertilizing potential of black soldier fly puparia and dead flies. The crop chosen is lettuce and the growth conditions are normal without the application of abiotic stress.

[0151] Preparation of samples of pupariums of Hermetia illucens according to the invention

[0152] Black soldier fly puparia (Hermetia illucens) were collected and ground in a grinder, sterilized and then dried. A powder is finally obtained (Hermetia illucens puparia powder according to the invention).

[0153] Preparation of samples of dead Hermetia illucens flies

[0154] The dead black soldier flies (Hermetia illucens) were collected and ground in a grinder, sterilized and then dried. A powder is finally obtained (dead Hermetia illucens fly powder according to the invention). Culture

[0155] During the growth phase, 4 measurement dates (diameter) are taken with a notation date before harvest.

[0156] At harvest (approximately 8 weeks after sowing), the aerial parts are collected in order to measure the fresh and dry biomass.

[0157] This test is carried out in a glass greenhouse under semi-controlled conditions allowing the plants to be maintained in optimal growth conditions.

[0158] PLANT MATERIAL: the tests are carried out on a model plant: lettuce (Lactusa sativa) of the AROA RZ variety at a rate of 1 seed per pot.

[0159] TEST SYSTEM:

[0160] Growing substrate: The tests are carried out in 3 L growing pots. The surface area of ​​the pots is 283.52 cm 2 The test substrate is a clod soil made up of peat with added sand and clay in a proportion of 70% Sand / 20% peat / 10% clay.

[0161] Growing conditions:

[0162] Filling the pots: All the growing pots are filled with the same weight of substrate without manual tamping.

[0163] For each method, the fertilizer product (frass, puparium, etc.) is added directly to the substrate.

[0164] Sowing: In each pot, 1 seed is sown evenly on the surface. 2 to 3 additional repetitions are added to compensate for possible losses at emergence. The pots are then watered by sub-irrigation so as to saturate the substrate with water.

[0165] Experimental setup: After sowing, the plants are placed in a glass greenhouse under semi-controlled conditions. Temperature and humidity are monitored using a recorder, and data is collected.

[0166] The trial is block randomized. It includes untreated controls.

[0167] The plants are kept in culture for approximately 8 weeks.

[0168] A positive control, i.e. poultry droppings (NPK: 4-4-4), is used (see methods 10, 11 and 19): this is a reference organic fertilizer.

[0169] The products and doses applied are as follows:

[0170] The results are as follows: af: when the letters are identical, then there is no significant difference between the values; when the letters are different, then there is a significant difference between the values; p < 0.05

[0171] By studying the diameter of the lettuce 2 weeks before harvest, we note the following:

[0172] Dose-effect for puparia: 16<3<4

[0173] Dose-effect for dead flies: 17<6<7 Dose-effect for droppings (positive control): 19<10<11.

[0174] A fertilizing effect was observed for all products and significantly different for modalities 4, 7 and 11 compared to the control (modality 1). The dead flies and puparia according to the invention accelerated the growth of lettuce 2 weeks before harvesting.

[0175] By studying the diameter of lettuce at harvest, we note the following:

[0176] Dose-effect for puparia: 16<3<4

[0177] Dose-effect for dead flies: 17<6<7

[0178] Dose-effect for droppings (positive control): 19<10<11.

[0179] A fertilizing effect is observed for all modalities and significantly superior to the control (modality 1).

[0180] By studying the fresh biomass (g), we observe a fertilizing effect for all modalities, and significantly higher than the control for modalities 3, 4, 6 and 7; and 10 and 11 (positive control).

[0181] By studying the fresh biomass (%), we observe a dose effect for puparia: 16<3<4, a dose effect for dead flies: 17<6<7; and a dose effect for droppings (positive control): 19<10<11.

[0182] By studying the dry biomass (%), we observe a dose effect for puparia: 16<3<4; a dose effect for dead flies: 17<6<7, and a dose effect for droppings (positive control): 19<10<11.

[0183] Pupariums and dead flies are therefore effective treatments to accelerate the growth of plants such as lettuce and / or to increase crop yield.

Claims

DEMANDS 1. Use of a composition comprising (i) Hermetia illucens puparia, (ii) whole dead flies or their fragments, or (iii) a mixture thereof, to accelerate plant growth and / or to increase crop yield, characterized in that the puparia (i) have the following profile, on a dry matter basis: a chitin content of less than or equal to 25% by weight relative to the total weight of puparium; a total fat content of at least 5% by weight relative to the total weight of puparium, and manganese at a content of at least 200 ppm on a dry matter basis, and the whole dead flies or their fragments are Hermetia illucens and have the following profile, on a dry matter basis relative to the total weight of dead flies: a chitin content of less than or equal to 10% by weight; a content of at least 25% by weight of total fats, and manganese at a level of less than 50 ppm on a dry matter basis.

2. Use according to claim 1, characterized in that the composition is a powder, preferably obtained by grinding.

3. Use according to claim 1 or 2, characterized in that the plants are cereals, preferably maize or wheat, or vegetable plants, preferably selected from salads, potatoes, green beans, cucumbers, spinach and carrots.

4. Use according to any one of claims 1 to 3, characterized in that the puparia (i) of Hermetia illucens have the following profile, on a dry matter basis: 5% to 25% by weight, preferably 10% to 25% by weight, of chitin relative to the total weight of puparium; 5% to 30% by weight, preferably 5% to 20% by weight, of total fat relative to the total weight of puparium; and 200 ppm to 2000 ppm of manganese, preferably 400 ppm to 1500 ppm, preferably 600 ppm to 1000 ppm, and / or the dead Hermetia illucens flies or their fragments have the following profile, on a dry matter basis: a content of less than or equal to 7% by weight of chitin relative to the total weight of dead flies; of 27% to 40% by weight of total fat relative to the total weight of dead flies; and of 5 ppm to 40 ppm of manganese.

5. Use according to any one of claims 1 to 4, characterized in that the acceleration of plant growth is an increase in aerial biomass (i.e. leaves, stems and flowers) of at least 10%, preferably at least 15%, preferably at least 20%, preferably at least 22%, compared to the same plant species not treated with the composition according to the invention, after at least 7 days of cultivation.

6. Use according to any one of claims 1 to 4, characterized in that the increase in crop yield is a significant increase in this yield, preferably this yield is measured by harvesting the aerial biomass (i.e. leaves, stems and flowers) and it is increased when this aerial biomass is increased by at least 10%, preferably by at least 15%, preferably by at least 20%, preferably by at least 22%, compared to the same crop not treated by the composition according to the invention, after at least 7 days of cultivation.

7. Plant seed coated with a composition comprising holometabolous insect puparia, preferably of Hermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof.

8. Seed according to claim 7, characterized in that the plant is a cereal, preferably maize or wheat.

9. Seed according to claim 7 or 8, characterized in that the composition is a powder or a paste.

10. A method for coating a seed, comprising the following steps: a) preparation of a composition comprising (i) holometabolous insect puparia, preferably of Hermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof, preferably of a powder of Hermetia illucens puparia, for example by grinding; and b) coating at least one seed with the composition obtained in step a).

11. A method for cultivating a plant on a substrate, comprising the following steps: a) preparation of a composition comprising (i) holometabolous insect puparia, preferably diHermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof, preferably a powder of diHermetia illucens pupariums, for example by grinding, in which the puparias (i) have the following profile, in dry matter: a chitin content less than or equal to 25% by weight relative to the total weight of puparium; a content of at least 5% by weight of total fats relative to the total weight of puparium, and manganese at a content of at least 200 ppm on a dry matter basis, and whole dead flies or their fragments are Hermetia illucens and have the following profile, by weight in dry matter relative to the total weight of dead flies: a content less than or equal to 10% by weight of chitin;a content of at least 25% by weight of total fats, and manganese at a content of less than 50 ppm on a dry matter basis; and b') application of the composition obtained in step a) to the substrate, or to the plant, for example to its roots or to its aerial parts such as leaves, flowers and / or stems, or to at least one seed, for example by coating, preferably the application is made to the substrate by irrigation or to at least one seed by coating.; 12. A process according to claim 10 or 11, characterized in that the coating in step b) or b') respectively is carried out by simply mixing the composition, preferably the powder, obtained in a), diluted in water, with at least one seed, and then optionally drying.

13. A method according to any one of claims 10 to 12, characterized in that the coating in step b) or b') respectively is carried out in a weight ratio (puparia in active matter): seeds of between 10 -4 and 10 -10 preferably between 2x10 -4 and 2x10 -9 .

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