Using insect pupariums to increase plant growth

Abstract

Use of Insect Puparia to Enhance Plant Growth. The present invention relates to the use of a composition comprising (i) holometabolous insect puparia, preferably of Hermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof, to accelerate plant growth and / or increase crop yield. It also relates to a plant seed coated with such a composition. Finally, it relates to a seed coating method and a plant cultivation method using this composition. Figure for abstract: none

Description

Title of the invention: Use of insect puparia to increase plant growth

[0001] The present invention relates to the use of a composition comprising (i) holometabolous insect puparia, (ii) whole dead flies or their fragments, or (iii) a mixture thereof, to accelerate plant growth and / or increase 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.

[0002] The search for new strategies aimed at maintaining or increasing the productivity of agricultural systems, while reducing the input of agricultural inputs, is of constant interest.

[0003] 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 spraying or by mixing into the soil.

[0004] However, such products must first be extracted, processed and / or purified, which is complex and time-consuming to implement.

[0005] Furthermore, early crop establishment is critical for successful cultivation, as it ensures good establishment. Good establishment limits the risk of destruction by pests or adverse weather conditions and accelerates initial plant growth. This generally results in a higher yield and / or greater plant resilience to external threats.

[0006] 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-based alternatives, especially recycled ones. There is especially a need for a bio-based alternative that is easy and quick to obtain and less expensive. This alternative is notably a means of valorizing a co-product (i.e., waste) generated in an industry.

[0007] The Applicant has now discovered, as shown in the examples, that coating cereal seeds, particularly maize, with a powder of black soldier fly (Hermetia illucens, or BSF) puparia increases aboveground biomass growth of maize a few days after sowing, compared to an untreated control. In particular, these effects are especially pronounced at low doses (i.e., greater effect at lower doses).

[0008] Such a puparium grind is very easy and quick to obtain, bio-based, and allows recycling of BSF breeding co-products.

[0009] The present invention therefore relates to the use of a composition comprising (i) holometabolous insect puparia, preferably Hermetia illucens, (ii) flies, preferably Hermetia illucens, dead whole or their fragments, or (iii) one of their mixtures, to accelerate plant growth and / or to increase crop yield.

[0010] The present invention also relates to a plant seed coated with a composition comprising (i) holometabolous insect puparia, preferably Hermetia illucens, (ii) flies, preferably Hermetia illucens, whole dead or their fragments, or (iii) one of their mixtures.

[0011] The composition comprising (i) holometabolous insect puparia, preferably Hermetia illucens, (ii) flies, preferably Hermetia illucens, whole dead or their fragments, or (iii) one of their mixtures, is also called "composition according to the invention".

[0012] The term “plants” preferably means cereals or vegetable crops. Preferably, cereals are selected from maize, wheat, rice, barley, millet (including sorghum), oats, and rye. Preferably, cereals are selected from maize and wheat. Preferably, vegetable crops are selected from salad greens such as lettuce, potatoes, green beans, cucumbers, spinach, and carrots.

[0013] By "seed" we mean the grain.

[0014] By "acceleration of plant growth" is meant an increase in aboveground 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.

[0015] By "increasing crop yield," we mean a significant increase in this yield. This yield can be measured by harvesting the biomass. Preferably, by "increasing crop yield," we mean that the aboveground biomass (i.e., leaves, stems, and flowers) of the crop 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 with the composition according to the invention, after at least 7 days of cultivation.

[0016] The composition according to the invention comprises (i) holometabolous insect puparia, (ii) whole dead flies or their fragments, or (iii) one of their mixtures.

[0017] According to a first embodiment, the composition according to the invention comprises (i) Holometabolous insect puparia. Holometabolous insects are a superorder of insects. The development of holometabolous insects is characterized by complete metamorphosis: an egg, then a larva (which differs greatly from the adults), then a pupa, and finally an imago (adult). Preferably, the holometabolous insect is chosen from among the Diptera, preferably from the Brachycera, preferably from the Stratiomyidae.

[0018] Preferably, the holometabolous insect is the black soldier fly (Hermetia illucens, or BSF).

[0019] The black soldier fly (Hermetia illucens, or BSF) is a fly of the order Diptera, of the family Stratiomyidae. The life cycle of this insect consists of 9 stages, namely: the egg, six larval stages, the pupa and the adult.

[0020] The cycle begins with an egg, oval in shape, approximately 1 mm long, and pale yellow or creamy white in color. This egg hatches after about 4 days, producing a larva.

[0021] Newly hatched larvae measure approximately 1.8 mm. At the end of their growth, they are broad and oval and can reach 27 mm in length and 6 mm in width. The larvae go 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 with each stage), and the development of setae. Between each larval stage, a molt occurs; the larva sheds its integument (exuvia), which has become too small. This shedding is called exuviation. The sixth larval stage is the prepupal stage. During this stage, the larvae turn reddish-brown.

[0022] Then the prepupae become immobile and begin their metamorphosis; they are then called pupae. The pupa differs from the other two nymphal forms in that the metamorphosis takes place during a process that includes all the stages of molting except elongation. 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 group of the structural proteins, which makes the exocuticle harder. As the procuticle (i.e., exo- and endocuticles) of the puparium detach from the future imago (adult), the whole takes on an ovoid shape.

[0023] After two to three weeks in the pupal stage, the adults emerge (imago emergence) and reproduce when they are sexually mature (2 days after emergence). During emergence, the imago extracts itself from the puparium.

[0024] The cuticle, or exoskeleton, is the outer layer secreted by the epidermis of insects, in this case Hermetia illucens. It is generally composed of three layers:

[0025] -the epicuticle, which is the thinnest and outermost layer of the cuticle (lower at 4 pm); this layer is waterproof and includes a waterproofing wax layer, as well as proteins and chitin, in smaller quantities;

[0026] -the exocuticle, which is the intermediate layer of the cuticle; it is composed essentially of hardened proteins, the tannins, which are responsible for the rigidity of the cuticle, chitin and possibly melanin; and

[0027] - the endocuticle, which is a thin, flexible layer made up of a mixture of proteins and chitin.

[0028] The exo- and endocuticles form the procuticle.

[0029] Preferably, according to a first embodiment, the composition according to the invention comprises (i) holometabolous insect puparia, preferably of Hermetia illucens.

[0030] By holometabolous insect puparium, preferably of Hermetia illucens, is meant an empty puparium, i.e., after the imago has emerged. These puparia are collected after the emergence of adult flies; typically they are by-products of BSF rearing. The puparium is the pupal case. This case is rigid. The puparium is distinct from larval exuviae, which are the exuviae of the first six larval stages.

[0031] The puparia of Hermetia illucens according to the invention generally have the following profile, in dry weight relative to the total weight of puparium: - a chitin content less than or equal to 25% by weight; - a content of at least 5% by weight of total fats.

[0032] Furthermore, the puparia of Hermetia illucens according to the invention generally contain manganese at a concentration of at least 200 ppm, preferably at least 400 ppm (on a dry matter basis). This manganese concentration is much higher than that of the larval exuviae. Indeed, by comparison, larval exuviae typically contain less than 110 ppm of manganese on a dry matter basis. This manganese, in association with the other constituents of the pupariae, appears to play a role in the observed increase in plant growth.

[0033] Preferably, the puparia of Hermetia illucens according to the invention have the following profile, in dry matter: - 5% to 25% by weight of chitin relative to the total weight of puparium; - 5% to 30% by weight of total fat relative to the total weight of puparium; and - from 200 ppm to 2000 ppm of manganese.

[0034] Preferably, the puparia of Hermetia illucens according to the invention have the following profile, in dry matter: - 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 materials total fats relative to the total weight of puparium; and - from 200 ppm to 2000 ppm of manganese, preferably from 400 ppm to 1500 ppm, preferably from 600 ppm to 1000 ppm.

[0035] The advantage lies on the one hand in the simplicity of use (no pre-processing or extraction step is necessary), and on the other hand in the interesting effects obtained.

[0036] The composition according to the invention comprises holometabolous insect puparia, preferably of Hermetia illucens, as the active ingredient. Preferably, this composition consists exclusively of holometabolous insect puparia, preferably of Hermetia illucens.

[0037] The composition comprising puparia of a holometabolous insect, preferably Hermetia illucens according to the invention, is preferably a powder or a paste. Indeed, preferably, the puparia of a holometabolous insect, preferably Hermetia illucens, are used in powder or paste form. For example, they can be obtained by grinding, for example with a mortar and pestle; the composition is then a puparium powder. Such a powder (or powder) of puparia of a holometabolous insect, preferably 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 only the chitin. For example, such a powder (or powder) of Hermetia illucens puparia according to the invention includes fats. Moreover, chitin is not the predominant component in puparium 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.

[0038] 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 selected from Brachycera, preferably from Stratiomyidae. Preferably, the whole dead flies or their fragments are dead black soldier flies (Hermetia illucens) or their fragments.

[0039] 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 after the emergence of the imago. They can be collected as is.

[0040] Dead Hermetia illucens flies or their fragments according to the invention generally have the following profile, in dry weight 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.

[0041] In addition, dead flies according to the invention generally contain manganese in a content of less than 50 ppm (on a dry matter basis).

[0042] Preferably, dead Hermetia illucens flies or their fragments according to the invention have the following profile, in dry matter: - a chitin content of less than or equal to 7% by weight relative to the total weight of dead flies; - 27% to 40% by weight of total fat relative to the total weight of dead flies; and - from 5 ppm to 40 ppm of manganese.

[0043] According to a third embodiment, the composition according to the invention comprises (iii) a mixture of holometabolous insect puparia, preferably of Hermetia illucens, and whole dead flies or their fragments.

[0044] Preferably, such a mixture comprises holometabolous insect puparia, preferably of Hermetia illucens, exhibiting the profile described above (ingredient (i)).

[0045] Preferably, such a mixture comprises whole dead flies or their fragments having the profile described above (ingredient (ii)).

[0046] The mixture can be made in any proportion of puparias relative to whole dead flies or their fragments.

[0047] 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 by-product of BSF rearing.

[0048] The composition according to the invention can be applied by any means. In particular, it can be applied directly to the growing medium, such as soil, for example by irrigation; or applied to the plants, for example on the roots, on 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.

[0049] By “substrate” is meant any substrate suitable for growing plants, preferably chosen from soil, potting soil, peat, sand and mixtures thereof.

[0050] 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 Hermetia illucens, (ii) whole dead flies or their fragments, or (iii) a mixture thereof. Preferably, the composition is a powder of Hermetia illucens puparia, for example obtained by grinding; and b. coating at least one seed with the composition obtained in step a).

[0051] Step a) of preparing the composition, preferably the powder, of holometabolous insect puparia, preferably Hermetia illucens, is simple. It is by example carried out by crushing the pupariums, for example with a mortar and pestle.

[0052] The pupariums are notably recovered in the form of fly breeding waste (by-products of BSF breeding).

[0053] The composition can also be obtained in step a) by grinding whole dead flies or their fragments. It can also be obtained by grinding a mixture of puparia and whole dead flies or their fragments.

[0054] Step b) includes 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, and then optionally drying.

[0055] Preferably, this coating step is carried out as follows: - The powder of holometabolous insect pupariums, preferably of Hermetia illucens, is mixed with water to obtain a solution. Preferably, the weight ratio (puparium powder): water is between 1:10 and 1:7; - then the supernatant is taken, which is called the "basic solution"; - we dilute this basic solution; - a mixture of diluted basic solution is prepared with water; - the diluted basic solution with water is applied to at least one seed; and - if necessary, let it dry.

[0056] Preferably, the coating in step b) is carried out in a weight ratio (puparia in active matter): seeds of between 10⁴ and 10¹⁰, preferably between 2x10⁴ and 2x10¹⁰A

[0057] Indeed, with such a ratio, the acceleration of plant growth is significantly improved, as shown in examples.

[0058] At the end of step b), a coated seed is obtained according to the invention.

[0059] The invention also relates to a method for cultivating a plant on a substrate, comprising the following steps:

[0060] 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

[0061] b') application of the composition obtained in step a) onto the substrate, or onto the plant, for example on its roots or on its aerial parts such as leaves, flowers and / or stems, or on at least one seed, for example by coating.

[0062] Step a) of the plant cultivation process is identical to that described above. This process allows for accelerated plant growth and / or increased crop yield.

[0063] Step b') comprises applying the composition obtained in step a) directly to the substrate, or to the plant, for example to its roots or aerial parts such as 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 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.

[0064] 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 process comprises the following steps c) and d):

[0065] c) preparation of the sowing with the seed from step b); and

[0066] d) cultivation of the seedling of step c).

[0067] Step c) includes preparing the sowing with the coated seed, obtained in step b').

[0068] The preparation of the sowing is carried out in a conventional manner, for example by sowing in the ground, then covering with a layer of soil, possibly moist.

[0069] Finally, step d) includes the cultivation of the seedling. The cultivation is also conventional, and is carried out under temperature and watering conditions adapted to each plant.

[0070] The following examples are given for illustrative purposes.

[0071] Example 1: Measurement of aboveground biomass in maize plants treated with pupariums according to the invention

[0072] Preparation of puparium samples

[0073] Black soldier fly (Hermetia illucens) puparia were collected and ground in a mortar and pestle to obtain a powder.

[0074] 2 g of this powder are mixed in 15 ml of water to obtain a solution. then collects the supernatant, which is called the "basic solution".

[0075] The following diluted samples are prepared:

[0076] Witness = water

[0077] Sample 1 = basic solution diluted to 10 1 (300 pl of basic solution + 2700 pl of water)

[0078] Sample 2 = basic solution diluted to 102 (300 pl of sample 1 + 2700 pl of water)

[0079] Sample 3 = basic solution diluted to 103 (300 pl of sample 2 + 2700 pl of water)

[0080] Sample 4 = basic solution diluted to 10⁴ (300 pl of sample 3 + 2700 pl of water)

[0081] Sample 5 = basic solution diluted to 105 (300 pl of sample 4 + 2700 pl of water).

[0082] Seed preparation

[0083] For each sample, a mixture of 3.8 ml of water and 220 ml is then prepared. sample (“slurry”). Shake for 15 seconds.

[0084] Next, 1.8 ml of the resulting mixture (slurry) is applied to 90.5 g of maize seeds (KWS genotype KXC387) placed in a plastic bag: specifically, the slurry is poured into the bag, the seeds are added, and the closed bag filled with air is stirred for 1 minute.

[0085] Seedling preparation

[0086] The seedlings are then prepared in trays of soil:

[0087] The trays are prepared with 1.5 kg of moist soil.

[0088] We sow with 10 rows of 10 seeds.

[0089] A 750 g layer of moist soil is added over the seeds.

[0090] The container is closed with a lid and incubated at 20°C during the day and 15°C at night, with a photoperiod of 16 hours. The starting point is J0.

[0091] Measurements and observations carried out

[0092] Aerial biomass is measured by taking images via the Canopeo tool on 3 different dates: J7, J8 and J9.

[0093] Results

[0094] The results are as follows:

[0095] [Tables 1] Canopeo Sample % deviation from control 1 1.033 ab 3% 2 1.033 ab 3% 3 1.178 ab 17% 4 1.203 a 20% 5 1.228 a 22% Control 1.003 b - Pr > F(model) Significant < 0.0001 Yes - Pr > F(dilution number) Significant 0.018 Yes -

[0096] The statistical method used is the ANOVA method with a threshold of 10%.

[0097] A significant improvement in aboveground biomass is observed within a few days after sowing, a sign of better start-up growth: up to +22% vs. Control.

[0098] A dose-effect is also clearly visible: a greater effect is observed for reduced doses (i.e. dilution 105).

[0099] Example 2: Measurement of aboveground biomass in maize plants treated with pupariums according to the invention

[0100] Preparation of puparium samples

[0101] Black soldier fly (Hermetia illucens) puparia were recovered and ground in a pestle and mortar to obtain a powder.

[0102] 5 g of this powder are mixed in 50 ml of water to obtain a solution. then collects the supernatant, which is called the "basic solution".

[0103] The following diluted samples are prepared:

[0104] Witness = water

[0105] Sample 1 = basic solution diluted to 10 1 (300 pl of basic solution + 2700 pl of water)

[0106] Sample 2 = basic solution diluted to 102 (300 pl of sample 1 + 2700 pl of water)

[0107] Sample 3 = basic solution diluted to 103 (300 pl of sample 2 + 2700 pl of water)

[0108] Sample 4 = basic solution diluted to 10⁴ (300 pl of sample 3 + 2700 pl of water)

[0109] Sample 5 = basic solution diluted to 105 (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 is then prepared ("slurry"). It is stirred for 15 seconds.

[0112] Next, 2.8 ml of the resulting mixture (slurry) is applied to 140 g of maize seeds (genotype LS201100171 from RAGT) placed in a plastic bag: specifically, the slurry is poured into the bag, the seeds are added, and the closed bag filled with air is stirred for 1 minute.

[0113] Seedling preparation

[0114] Next, the seedlings are prepared in trays of soil:

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

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

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

[0118] The container is closed with a lid and incubated at 20°C during the day and 15°C at night, with a photoperiod of 16 hours. The starting point is J0.

[0119] Measurements and observations carried out

[0120] We measure the aerial biomass, by taking images via the Canopeo tool, on 2 different dates: J7 and J8.

[0121] Results

[0122] The results are as follows:

[0123] [Tables2] Canopeo Sample (Day 7) % deviation from control (Day 7) Canopeo (Day 8) % deviation from control (Day 8) 1 4.738 ab 3.903 a 2 4.930 ab 4.103 a 3 4.715 b 3.800 a 4 4.803 ab 3.953 a 5 5.283 a 106% 4.358 a 115% Control 4.983 ab - 3.790 a - Pr > F(model) Significant 0.039 Yes - 0.159 No - Pr > F(dilution number) Significant 0.097 Yes - 0.250 No -

[0124] At J7, a significant improvement in aboveground biomass is observed (only for the lowest doses, i.e. 106), and a decrease in growth for the other doses (vs. Control).

[0125] At J8, an improvement in aboveground biomass growth is observed for all modalities, with better performance for the lowest doses: + 15% at 10 6.

[0126] Example 3: Measurement of aboveground biomass in lettuce plants treated with pupariums according to the invention

[0127] Preparation of puparium samples

[0128] Black soldier fly (Hermetia illucens) puparia were recovered and ground in a pestle and mortar to obtain a powder.

[0129] 5 g of this powder are mixed in 50 ml of water to obtain a solution. then collects the supernatant, which is called the "basic solution".

[0130] The following diluted samples are prepared:

[0131] Witness = water

[0132] Sample 2 = base solution diluted to 102 (the 50 ml of base solution are mixed with 450 ml of water)

[0133] Sample 3 = basic solution diluted to 103 (50 ml of sample 2 + 450 ml of water)

[0134] Sample 4 = basic solution diluted to 10⁴ (50 ml of sample 3 + 450 ml of water)

[0135] Sample 5 = base solution diluted to 105 (50 ml of sample 4 + 450 ml of water)

[0136] Sample 6 = basic solution diluted to 106 (50 ml of sample 5 + 450 ml of water).

[0137] Seedling preparation

[0138] The seedlings are then prepared in a mini-greenhouse:

[0139] 72 pots are used, and 3 lettuce seeds per pot are planted in potting soil sifted.

[0140] Incubate at 20°C for 22 days.

[0141] Next, 100 ml of one of the samples is poured onto the ground using a peristaltic pump for each pot. This corresponds to treatment no. 1 (J0). This treatment is repeated on J11 (treatment no. 2), J17 (treatment no. 3) and J28 (treatment no. 4).

[0142] Measurements and observations carried out

[0143] Aerial biomass is measured by taking images via the Canopeo tool at J50 (but also during the experiment).

[0144] Furthermore, at J50, the aerial and root biomass is collected and incubated at 80°C for drying. Two days later, this dried biomass is weighed.

[0145] Results

[0146] The results are as follows:

[0147] [Tables3] Canopeo Sample at Day 50 Dry Aboveground Biomass % Difference from Control (Day 50) Canopeo at Day 50 Fresh Aboveground Biomass % Difference from Control (Day 50) 2 3.065 a +54% 58.950 a +69% 3 2.273 b +14% 40.990 b +18% 4 2.108 b +6% 36.650 b +5% 5 2.435 b +22% 42.788 b +23% 6 2.348 b +18% 43.060 b +24% Control 1.993 b 34.800 b Pr > F(model) Significant 0.001 Yes 0.000 Yes Pr > F(dilution number) Significant 0.000 Yes < 0.0001 Yes

[0148] A significant improvement in aboveground biomass (fresh and dry) is observed, therefore an improvement in plant growth for all doses.

[0149] These results are visible throughout the plant's growth.

[0150] There is no significant effect on germination capacity.

Claims

Claims

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

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 corn or wheat, or market garden plants, preferably chosen from salads, potatoes, green beans, cucumbers, spinach and carrots.

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

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

6. Seed according to claim 5, characterized in that the plant is a cereal, preferably corn or wheat.

7. Seed according to claim 5 or 6, characterized in that the composition is a powder or a paste.

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

9. A method of growing a plant on a substrate, comprising the following steps: a) preparing a composition comprising (i) puparia of a holometabolous insect, preferably of Hermetia illucens, (ii) whole dead flies or fragments thereof, or (iii) a mixture thereof, preferably a powder of puparia of Hermetia illucens, for example by grinding, in which the puparia (i) have the following profile, in dry matter: a content of less than or equal to 25% by weight of chitin relative to the total weight of puparia; a content of at least 5% by weight of total fat relative to the total weight of puparium, and manganese in a content of at least 200 ppm on dry matter, and the whole dead flies or their fragments are Hermetia illucens and have the following profile, by weight of dry matter relative to the total weight of dead flies: a content of less than or equal to 10% by weight of chitin; a content at least equal to 25% by weight of total fats, and manganese in a content of less than 50 ppm on dry matter; and b') application of the composition obtained in step a) on the substrate, or on the plant, for example on its roots or on its aerial parts such as the leaves, the flowers and / or the stems, or on at least one seed, for example by coating, preferably the application is made on the substrate by irrigation or on at least one seed by coating.

10. Method according to claim 8 or 9, characterized in that the coating of step b) or b') respectively is carried out by simple mixing of the composition, preferably the powder, obtained in a), diluted in water, with at least one seed, then optionally drying, preferably the coating of step b) or b') respectively is carried out in a weight ratio (puparia in active material): seeds of between 10 4 and 10 10, preferably of between 2x10 4 and 2x109.