Sun protection for crops

Abstract

The present invention relates to a composition comprising algae, in particular Spirulina platensis and Chlorella, and its use for the treatment of crops such as fruits, vegetables and arable crops against heat stress, in particular sunburn.

Description

[Technical field]

[0001] The present invention relates to compositions comprising algae and their use for the treatment of crops such as fruits, vegetables and arable crops against heat stress, in particular sunburn. [Background technology]

[0002] Heat stress, especially sunburn, is a serious problem most prevalent in areas where high temperature and solar radiation are combined, affecting the quality of fruit, vegetables and arable crops and can cause losses of up to 40% in crops such as melons, pumpkins, tomatoes, peppers, eggplants, cucumbers, apples, strawberries and berries.

[0003] When fruits or vegetables are exposed to excessive heat and sunlight, the skin may turn brown or black. Severe heat damage can often cause surface cracks and complete tissue decay.

[0004] Additionally, drought stress may contribute to sunburn by reducing leaf shading and fruit size.

[0005] There are three types or stages of sunburn that affect crops.

[0006] First, sunburn necrosis occurs on the sun-exposed side of the crop, and the skin, pericarp, and crop tissue begin to die. The integrity of the cell membrane is lost and the cell contents (electrolytes) begin to leak out. The lesions can be white to brown, and the crop is unsellable.

[0007] The critical temperature of crop tissue for sunburn necrosis varies with the type of crop. Several studies have shown that the temperature threshold of crop skin for sunburn necrosis is about 38°C to about 40°C for cucumber, about 40°C to about 43°C for pepper, and about 50°C to about 53°C for apple.

[0008] The second type, sun browning, is also the most common. Sun browned crops are potentially saleable but of lower quality.

[0009] This sunburn causes loss of pigment, resulting in yellow, bronze or brown spots on the sun-exposed sides of the crop due to pigment destruction or modification.

[0010] This type of sunburn occurs at temperatures approximately 5°C lower than those required for sunburn necrosis.

[0011] The third type of sunburn is photooxidative sunburn, which occurs when a shaded crop is suddenly exposed to sunlight, for example due to late pruning or bad weather causing a sudden loss of leaf cover.

[0012] Because crop plants are not acclimated to high light levels, a sudden burst of light can cause photobleaching and the crop tissue begins to die. Damaged tissue is often white in color.

[0013] This type of sunburn occurs at lower temperatures than other types of sunburn.

[0014] Sun crop management options include several options, all of which have some disadvantages.

[0015] The first option is above-ground or evaporative cooling (EC), which cools the crop surface by the direct application of cold water. This is a reliable method but requires a large investment to install, operate and maintain the cooling system.

[0016] For crops where the majority of exposed crops are at risk of sunburn, protective netting is an option, however the high infrastructure costs make it impractical for large areas.

[0017] There are currently several products on the market that are used to protect crops from sunburn on a field scale.

[0018] Surround™ contains kaolin which upon application forms a white, barrier coating over the crop, protecting it from sunburn and heat stress.

[0019] Screen Duo™ consists of hydrous kaolin (aluminium silicate) that, when applied to crops, forms a visible particle film that reflects harmful UV and IR light and reduces the crop's temperature.

[0020] Purshade™ contains calcium carbonate, which acts as a protective coating against harmful solar radiation.

[0021] Parka™ is a blend of phospholipids in a cellulose matrix designed to supplement the cuticle of developing fruits and leaves. It is used to reduce microfractures, minimize fruit cracking, and provide protection from sunburn.

[0022] Raynox™ contains water, carnauba wax, organically modified clay and emulsifiers and is used to protect apples from sun browning.

[0023] Products based on kaolin clay, calcium carbonate or talc such as Surround, Screen Duo and Purshade leave a white particulate film on the crop upon application, which has several drawbacks, namely the added cost of washing and cleaning (i.e. brushing) the crop during or after harvest. Furthermore, even after washing, traces of the product may still be present in hard to reach parts of the crop such as the calyx, stem and ridges.

[0024] Furthermore, when overhead irrigation is used or during rainy weather, the material may be partially washed off, reducing its effectiveness and requiring additional applications.

[0025] Produce buyers may have standards regarding the use of particulate membranes and may not tolerate products with visible residues. Summary of the Invention [Problem to be solved by the invention]

[0026] It is therefore an object of the present invention to provide a product which may alleviate the disadvantages of the prior art and provide an efficient solution for the protection of crops against heat stress, in particular sunburn.

[0027] The present invention provides a composition and its use for the treatment of crops such as fruits, vegetables and arable crops against heat stress, in particular sunburn, where algae are the main component of such a composition.

[0028] So far, only algae, or in particular one representative of algae, Spirulina platensis, is known as a fertilizer in agriculture. [Means for solving the problem]

[0029] According to the present invention there is provided a composition comprising algae or mixtures thereof for use as a treatment for crops against heat stress, in particular sunburn heat stress.

[0030] According to the present invention, the algae is selected from Spirulina and Chlorella, and mixtures thereof.

[0031] Such compositions offer the advantage of effective heat stress protection of crops without any residue problems and without the need for pre- or post-harvest cleaning of the crop.

[0032] The composition according to the invention may further comprise one or more ingredients selected from osmoprotectants, elicitors, binders and auxiliaries, and any mixtures thereof.

[0033] Furthermore, the compositions according to the invention can be supplied as liquid compositions which require only a dilution step, or can be provided in powder form or as granular products which require dissolving the powder or granules in a suitable solvent such as water and, optionally, a dilution step.

[0034] Disclosed herein is a kit comprising the composition according to the present invention. The kit may also further comprise a suitable solvent or mixture thereof.

[0035] Further provided herein are methods for protecting crops from heat stress and uses of algae for heat stress protection.

[0036] Other aspects of the invention are further described in the following sections. [Brief description of the drawings]

[0037] [Figure 1] Incidence of sunburn [Diagram 2] Total Sunburn Incidence - 30 Days After First Application [Diagram 3] Surface damage intensity - 30 days after first treatment [Figure 4] Incidence of sunburn [Diagram 5] Total Sunburn Incidence - 30 Days After First Application [Figure 6] Surface damage intensity - 30 days after first treatment [Figure 7] Incidence of sunburn [Figure 8] Total Sunburn Incidence - 43 Days After First Application [Figure 9] Incidence of sunburn [Figure 10] Total Sunburn Incidence - 43 Days After First Application [Figure 11] Total Sunburn Incidence - 55 Days After First Application [Figure 12] Incidence of sunburn [Figure 13] Total Sunburn Incidence - 157 Days After First Application DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The following abbreviations are used, with the following meanings: DAA = Days after first treatment application SP = Spirulina platensis EC=Ectoine AC=λ-carrageenan BE=Betaine LYS = L-lysine Composition and formulation are terms used interchangeably herein having the same meaning.

[0039] Materials and Methods Compositions containing Spirulina as a representative algae, either alone or mixed with other ingredients, were prepared by dissolving commercially available freeze-dried Spirulina platensis in a given amount of water to obtain a solution containing a given concentration of Spirulina.

[0040] All other ingredients were added sequentially to the solution so that they were present at the given concentrations as indicated in the examples, depending on the composition of interest.

[0041] Two control groups were used for efficacy comparison purposes.

[0042] The control was a group to which no treatment was applied in order to observe the effect and extent of sunburn on unprotected crops.

[0043] The second control, Surround or Parka, was an application of the current commercially available composition, namely Surround (a membrane of calcined kaolin particles) or Parka (a blend of phospholipids in a cellulose matrix). EXAMPLES

[0044] The following examples illustrate the compositions according to the invention and their effectiveness in protecting crops from heat stress.

[0045] Example 1. Mango fruit, test 1 Test location: Thailand Cultivar: Nam Dok Mai Mango test plot 4 m×12 m=48 m 2 , 4 replicates

[0046] The spray solution was prepared as follows: Surround: 10,000 g of the commercially available Surround product was dispersed in 1,200 L of water. SP: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water. SP+EC: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water and 400 ml of ectoine solution at a concentration of 2 g / L was added. SP+BE: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water and 700 ml of betaine dispersion with a concentration of 360 g / L was added.

[0047] Applicable dates and weather:

[0048] [Table 1]

[0049] Applicable equipment: Electric Sprayer - Hollow Cone Type

[0050] Evaluation Protocol: Diseased fruit severity data was visually estimated as the percentage of a given mango fruit affected by insects and disease prior to application of the first treatment. The number of diseased fruits was counted on 20 plants per plot.

[0051] [Table 2]

[0052] result: Figure 1. Incidence of sunburn Figure 2. Total sunburn incidence – 30 days after first application Figure 3. Surface damage intensity - 30 days after first treatment

[0053] Example 2. Mango fruit, test 2 Test location: Thailand Cultivar: Nam Dok Mai Mango test plot 4 m×12 m=48 m 2 , 4 replicates

[0054] Application amount per hectare: Surround: 10,000 g of the commercially available Surround product was dispersed in 1,200 L of water. SP+AC: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water, and 500 ml of 2 g / L λ-carrageenan solution was added. SP+LYS: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water, and 2000 ml of L-lysine solution with a concentration of 50 g / L was added. SP+BE+AC+EC: 1500 g of freeze-dried Spirulina platensis was dispersed in 1200 L of water, and 700 ml of 360 g / L betaine dispersion, 500 ml of 2 g / L λ-carrageenan solution, and 2000 ml of 50 g / L L-lysine solution were added.

[0055] Applicable dates and weather:

[0056] [Table 3]

[0057] Applicable equipment: Electric Sprayer - Hollow Cone Type

[0058] Evaluation Protocol: Diseased fruit severity data was visually estimated as the percentage of a given mango fruit affected by insects and disease prior to application of the first treatment. The number of diseased fruits was counted on 20 plants per plot.

[0059] [Table 4]

[0060] result: Figure 4. Incidence of sunburn Figure 5. Total sunburn incidence – 30 days after first application Figure 6. Surface damage intensity - 30 days after first treatment

[0061] Example 3. Apple fruit, test 1 Test location: Europe Cultivar: Apache Test area: 7.25 m x 3.5 m = 21.8 m 2 , 4 replicates

[0062] Application amount per hectare: Surround: 10,000 g of the commercially available Surround product was dispersed in 500 L of water. SP: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water. SP+BE: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water and 700 ml of betaine dispersion with a concentration of 360 g / L was added. SP+EC: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water and 400 ml of ectoine solution with a concentration of 2 g / L was added. SP+AC: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water, and 500 ml of 2 g / L λ-carrageenan solution was added.

[0063] Applicable dates and weather:

[0064] [Table 5]

[0065] Applicable equipment: Electric Sprayer - Hollow Cone Type

[0066] Evaluation Protocol: The number of diseased fruits was counted on three medium sized trees on each side of each plot. No diseased fruits were removed during the evaluation. No sunburn damage was observed prior to the first application.

[0067] [Table 6]

[0068] result: Figure 7. Incidence of sunburn Figure 8. Total sunburn incidence – 43 days after first application

[0069] Example 4. Apple fruit, test 2 Test location: Europe Cultivar: Golden Delicious Test area: 7.25 m x 3.5 m = 21.8 m 2 , 4 replicates

[0070] Application amount per hectare: Surround: 10,000 g of the commercially available Surround product was dispersed in 500 L of water. SP+BE+AC: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water, and 700 ml of a 360 g / L betaine dispersion and 500 ml of a 2 g / L λ-carrageenan solution were added. SP+BE+EC: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water, and 700 ml of a 360 g / L betaine dispersion and 400 ml of a 2 g / L ectoine solution were added. SP+AC+EC: 1500 g of freeze-dried Spirulina platensis was dispersed in 500 L of water, and 500 ml of 2 g / L λ-carrageenan solution and 400 ml of 2 g / L ectoine solution were added.

[0071] Applicable dates and weather:

[0072] [Table 7]

[0073] Applicable equipment: Electric Sprayer - Hollow Cone Type

[0074] Evaluation Protocol: The number of diseased fruits was counted on three trees on each side of each plot. No diseased fruits were removed during the evaluation. No sunburn damage was observed prior to the first application.

[0075] [Table 8]

[0076] result: Figure 9. Incidence of sunburn Figure 10. Total sunburn incidence – 43 days after first application

[0077] Example 5. Apple fruit, test 3 Test location: United States Cultivar: Gala Test area: 5 m x 7 m = 35 m 2 , 4 replicates

[0078] Application amount per hectare: Parka: 10 L of commercial product was emulsified in 400 L of water. SP: 1500 g of freeze-dried Spirulina platensis was dispersed in 400 L of water. SP+BE: 1500 g of freeze-dried Spirulina platensis was dispersed in 400 L of water and 700 ml of betaine dispersion with a concentration of 360 g / L was added. SP+AC: 1500 g of freeze-dried Spirulina platensis was dispersed in 400 L of water, followed by the addition of 500 ml of 2 g / L λ-carrageenan solution.

[0079] Effective date:

[0080] [Table 9]

[0081] Applicable equipment: Electric Sprayer - Hollow Cone Type

[0082] Evaluation Protocol: 100 fruits per tree were examined and diseased fruits were counted.

[0083] [Table 10]

[0084] result: Figure 11. Total sunburn incidence – 55 days after first application

[0085] Example 6. Citrus fruits Test location: United States Cultivar: Seedless Fairchild tangerine (Citrus tangerine / Fairchild) Test area: 7 m x 7 m = 49 m 2 , 4 replicates

[0086] Application amount per hectare: Surround: 10 kg dispersed in 1000 L of water SP: 1500 g of freeze-dried Spirulina platensis was dispersed in 1000 L of water. SP+BE: 1500 g of freeze-dried Spirulina platensis was dispersed in 1000 L of water and 700 ml of betaine dispersion with a concentration of 360 g / L was added. SP+AC: 1500 g of freeze-dried Spirulina platensis was dispersed in 1000 L of water, and 500 ml of λ-carrageenan solution with a concentration of 2 g / L was added.

[0087] Effective date:

[0088] [Table 11]

[0089] Applicable equipment: Bacman Flat Fan Sprayer - Nozzle Size 8002 - Compressed CO2 as High Pressure Gas

[0090] Evaluation Protocol: All fruits on the tree were counted and the percentage of diseased fruits was calculated.

[0091] [Table 12]

[0092] result: Figure 12. Incidence of sunburn Figure 13. Total sunburn incidence – 157 days after first application

[0093] The results obtained show that spirulina, alone or in combination with other ingredients, provides good results in protecting various crops from heat stress.

[0094] composition The features and characteristics illustrated and / or described herein in connection with the various examples and / or compositions presented herein may each be combined with the features and characteristics of other examples and / or compositions also provided herein, and such modifications and variations are intended to be included within the scope of the present invention.

[0095] The composition according to the present invention comprises algae selected from Spirulina and Chlorella, and mixtures thereof.

[0096] The composition according to the invention may further comprise one or more ingredients selected from osmolytes and / or elicitors and / or binders.

[0097] According to the present invention, the osmolyte is selected from amino acids selected from betaine, ectoine, trehalose, proline, lysine, glutamic acid, cysteine ​​and glycine, the elicitor is selected from auxins, gibberellins, salicylic acid, methyl salicylate, jasmonic acid, benzoic acid, chitosan, β-glucan and carrageenan (e.g., λ-carrageenan), and the binder is selected from gum arabic, xanthan gum, diutan gum, cellulose and alginates, waxes such as carnauba wax or candelilla wax, any mixtures thereof being contemplated herein.

[0098] The compositions disclosed herein may further comprise one or more agriculturally acceptable adjuvants or auxiliary agents.

[0099] An adjuvant or auxiliary in the context of the present invention is a component that enhances the performance effect of the formulation.

[0100] Examples of adjuvants and auxiliaries are agents that enhance one or more of the following effects: retention, diffusion, adhesion to leaf / crop surfaces, penetration, physical, chemical, technological and / or biological effects, and the like.

[0101] It is an aspect of the present invention to provide a composition as described above additionally comprising at least one auxiliary component selected from the group comprising emulsifiers, solvents, surfactants, carriers, dispersants, thickeners, hydrophobizing agents, water retention agents, bulking agents, solid carriers, defoamers and / or other auxiliary agents.

[0102] The compositions of the present invention may be formulated into any conventional type of pesticide composition, such as solutions, emulsions, suspensions, dusts, powders, pastes, granules, compacts, capsules and mixtures thereof.

[0103] Examples of types of compositions are suspensions (e.g. SC, OD, FS), emulsifiable concentrates (e.g. EC), emulsions (e.g. EW, EO, ES, ME), capsules (e.g. CS, ZC), pastes, troches, wettable powders or dusts (e.g. WP, SP, WS, DP), compacts (e.g. BR, TB), granules (e.g. WG, SG, GR), etc.

[0104] According to the present invention, the compositions disclosed herein may be provided as liquid compositions and / or powders and / or granules.

[0105] For example, a liquid composition contemplated herein, but not limited to the examples provided herein, is the following: one or more liquid compositions of algae; A liquid composition comprising one or more algae and one or more components selected from an elicitor, an osmolyte, an auxiliary, and any mixture thereof; A liquid composition of one or more algae in one container provided with a second container containing a liquid composition of one or more components selected from elicitors, osmolytes and adjuvants, and mixtures thereof.

[0106] Furthermore, the powder and / or granular form may include One or more algal powder and / or granule compositions, A powder and / or granular composition comprising one or more algae and one or more components selected from elicitors, osmolytes, binders and auxiliaries, and mixtures thereof; A powder and / or granular composition of one or more algae in one container provided with a second container containing a powder and / or granular composition of one or more components selected from elicitors, osmolytes, binders and auxiliaries, and mixtures thereof; It can be provided as.

[0107] The liquid compositions described above can be prepared, for example, by mixing the selected algae and / or other ingredients described herein in a suitable solvent and / or diluent.

[0108] An example of a suitable solvent and / or diluent according to the present invention is water.

[0109] Furthermore, any liquid composition as described above may be provided with any powder and / or granular composition disclosed above, and vice versa.

[0110] Any of the above compositions can be supplied as a kit, for example, one or more liquid algal compositions provided in one container supplied with a second container containing a powder and / or granular composition of one or more components selected from, but not limited to, elicitors, osmolytes, binders and adjuvants, and mixtures thereof.

[0111] Any of the above compositions and / or kits may further be supplied with any additional agriculturally acceptable solvent and / or diluent.

[0112] All formulations described herein can be prepared in a known manner, for example by mixing the active compound with the other ingredients and / or auxiliaries.

[0113] Methods for preparing powders and / or granules are known in the art, for example as disclosed in the article by S. Shanmugam Granulation techniques and technologies: recent progresses, Bioimpacts, 2015, 5(1), 55-63.

[0114] Although it is preferred to formulate commercial products as concentrates, end users will typically use dilute formulations, and both concentrated and diluted compositions are contemplated and disclosed herein. Thus, the content of algae and / or osmolytes and / or elicitors and / or other adjuvants prepared from concentrated formulations can vary within wide limits.

[0115] The composition according to the present invention comprises algae in a concentration between 1 g / L and 500 g / L.

[0116] Furthermore, when osmolytes and / or elicitors are present in the composition according to the invention, their concentrations may vary from 0.0001 g / L to 500 g / L.

[0117] Provided herein is a method of protecting a crop from heat stress comprising applying to the crop any of the compositions disclosed herein.

[0118] Application to crops is carried out in a conventional manner appropriate to the application form, for example by mixing or dissolving the concentrate or granules, respectively, in a suitable solvent, then further diluting with a suitable diluent to the desired concentration, and spraying the same onto crops using a variety of mechanical or manual sprayers.

[0119] The compositions according to the invention find application in the protection of crops selected from fruit, vegetables and arable crops against sunburn.

[0120] Further, the fruits are selected from melons, apples, pears, mangoes, citrus fruits, grapes, peaches, raspberries, gooseberries, cherries, kiwi, the vegetables are selected from cucumbers, tomatoes and pumpkins, and the arable crops are selected from potatoes, sugar beets, corn, oilseed rape, cereals and soybeans.

[0121] In accordance with the present invention, provided herein is a method of making the heat stress protectant composition disclosed herein, comprising the step of mixing algae with water.

Claims

1. 1. Use of an agricultural composition comprising algae for treating crops against sunburn, said algae being Spirulina platensis.

2. The use described in claim 1, wherein the composition further comprises one or more components selected from osmoregulators, elicitors, binders and auxiliaries, and mixtures thereof.

3. the osmolyte is selected from betaine, ectoine, trehalose, and an amino acid selected from the following amino acids: proline, lysine, glutamic acid, cysteine, and glycine; the elicitor is selected from auxin, gibberellin, salicylic acid, methyl salicylate, jasmonic acid, benzoic acid, chitosan, β-glucan, and carrageenan; The binder is selected from gum arabic, xanthan gum, diutan gum, cellulose and alginates, waxes selected from carnauba wax and candelilla wax, and any mixtures thereof; 3. The use according to claim 2.

4. The use described in any one of claims 1 to 3, wherein the composition is liquid.

5. 5. The use according to any one of claims 1 to 4, wherein the algae is present in a concentration of from 1 g / L to 500 g / L.

6. The use according to any one of claims 2 to 5, wherein the one or more osmolytes are present in a concentration of from 0.0001 g / L to 500 g / L.

7. The use according to any one of claims 2 to 6, wherein the one or more elicitors are present in a concentration of from 0.0001 g / L to 500 g / L.

8. The use described in any one of claims 1 to 3, wherein the composition is in the form of a powder or granules.

9. The use according to any one of claims 1 to 8, wherein the crop is selected from fruits, vegetables and arable crops.

10. 10. The use according to claim 9, wherein the fruits are selected from melon, apple, pear, mango, citrus fruits, grapes, peaches, raspberries, gooseberries, cherries, kiwi, the vegetables are selected from cucumber, tomato and pumpkin, and the arable crops are selected from potato, sugar beet, corn, oilseed rape, cereals and soybeans.

11. A method for protecting crops against sunburn, comprising the step of applying to said crops a composition as defined in any one of claims 1 to 10.

12. The method of claim 11, wherein the crop is selected from fruits, vegetables and arable crops.

13. The method of claim 12, wherein the fruits are selected from melons, apples, pears, mangoes, citrus fruits, grapes, peaches, raspberries, gooseberries, cherries and kiwi, the vegetables are selected from cucumbers, tomatoes and pumpkins, and the arable crops are selected from potatoes, sugar beets, corn, oilseed rape, cereals and soybeans.

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