SEED COATING ADDITIVE

Abstract

A seed coating composition for coating plant seeds. The coating composition comprises a polymeric binder and/or resin, and a hydrolysed protein. The seed coating composition optionally comprises an agrochemical active and/or nutrient, and the composition is used to improve the seed's physical qualities, especially the seed's ability to resist drought or poor water conditions and/or high salinity conditions. There is also provided a method of making the formulations, and for treating seeds or bulbs with seed coating formulation.

Claims

1. A seed coating composition comprising a polymeric binder and/or resin, and a hydrolysed protein.

2. The composition according to claim 1, wherein the hydrolysed protein present is derived from either animal or vegetable sources, or by fermentation.

3. The composition according to claim 1, wherein the hydrolysed protein comprises amino acid chains formed from hydrolysing a protein.

4. The composition according to claim 1, wherein the hydrolysed protein is hydrolysed wheat protein produced by enzyme hydrolysis.

5. The composition according to claim 1, wherein the molecular weight (weight average) of the hydrolysed protein is in the range from 50 Da to 50,000 Da.

6. The composition according to claim 1, wherein the hydrolysed protein comprises on average in the range from 2 to 15 amino acids.

7. The composition according to claim 1, wherein the amount of free amino acid in the hydrolysed protein is less than 60 wt. %.

8. The composition according to claim 1, wherein the polymeric binder is selected from the group consisting of polyvinyl acetates, polyvinyl acetate copolymers, polyvinyl alcohols, polyvinyl alcohol copolymers, polyurethane, celluloses (including ethylcelluloses, methylcelluloses, hydroxymethylcelluloses, hydroxypropylcelluloses, carboxymethylcelluloses, and hydroxymethylpropyl celluloses), polyvinylpyrrolidones, dextrins, maltodextrins, starchs, polysaccharides, fats, oils, proteins, gum arabics, shellacs, vinylidene chloride, vinylidene chloride copolymers, calcium lignosulphonates, polyacrylates, acrylic copolymers, polyvinylacrylates, zeins, casein, gelatine, chitosan, pullulan, polyethylene oxide, polyethylene glycol, acrylamide polymers, acrylamide copolymers, polyhydroxyethyl acrylate, methylacrylamide polymers, poly(N vinylacetamide), sodium alginate, polychloroprene, and syrups.

9. The composition according to claim 8, wherein the polymeric binder is selected from the group consisting of polyvinyl acetates, polyvinyl alcohols, hydroxypropylmethylcellulose, polysaccharides (other than starch), proteins, polyethylene glycol, polyvinyl pyrrolidones, and polyacrylates.

10. The composition according to claim 1, wherein the polymeric binder has a molecular weight (weight average) in the range from 1,000 to 40,000.

11. The composition according to claim 1, wherein the polymeric binder is a copolymer of acrylic acid with alkyl methacrylates or styrene with a molecular weight of less than 20,000, and a Tg of more than 30° C.

12. The composition according to claim 1, wherein the resin is a rosin resin or rosin ester.

13. A method of forming a seed coating composition which comprises combining an aqueous composition pre-blend comprising a polymeric binder and/or resin, and a hydrolysed protein pre-blend.

14. A method of coating seed which comprises applying a seed coating composition comprising a polymeric binder and/or resin, and a hydrolysed protein, to a seed.

15. A seed with a coating comprising the composition according to claim 1.

16. The coated seed according to claim 15, wherein the seed is selected from the group consisting of corn, sunflower, wheat, lettuce, and onions.

17. A method for increasing drought and salinity resistance of a seed which comprises coating the seed with the composition according to claim 1.

18. The method according to claim 17, wherein a plant formed from a seed coated with the composition also has increased drought and salinity resistance.

19. A two component system comprising a first component comprising a polymeric binder and/or resin, and a second component comprising a hydrolysed protein, suitable for combining to form a seed coating composition in accordance with claim 1.

Description

EXAMPLES

[0140] In order that the present invention may be more readily understood, reference will now be made, by way of example, to the following description.

[0141] It will be understood that all tests and physical properties listed have been determined at atmospheric pressure and room temperature (i.e. 25° C.), unless otherwise stated herein, or unless otherwise stated in the referenced test methods and procedures.

[0142] The following test methods were used to determine performance of the drought resistance additives.

[0143] Moisture Stress Test on Paper

[0144] Evaluation of the hydrolysed protein products was done using various germination testing methods. Germination testing on paper was done in moisture stress testing in which the density of water was manipulated via PEG (Polyethylene Glycol).

[0145] To test the abiotic stress factor of reduced moisture availability a moisture stress test on paper was performed on the objects. The moisture stress test consisted of performing a germination test with moisture stress controlled via Polyethylene Glycol (PEG). Lighting in combination with a solution of PEG has a negative effect on plant development. All PEG testing was done in a phytotron with a 9-hour long light and 15-hour dark cycle with a white paper sheet on top of the germination containers to shield the plants from direct light. Germinating with no light will result in elongated plants.

[0146] An assessment method as shown in Table 1 was used to classify plant development. The classification was used to indicate leaf development after germination, with A class representing good development down to D representing poor development.

TABLE-US-00001 TABLE 1 Classification in altered assessment method of corn Class Criteria Greentip visible from coleoptile Greentip from coleoptile visible from tip/beginning of coleoptile A class Stem, cotyle, leaf >4 cm above fold B class Stem, cotyle, leaf 2-4 cm above fold C class Stem, cotyle, leaf <2 cm above fold D class Germinated but below fold

[0147] Evaluation of Sunflower objects was done via root length measurement.

[0148] Moisture Stress Test in Soil

[0149] Three sowings were done per object; the tray was filled with 60 cc potting soil, 25 wheat seeds sown, and covered with 30 cc of potting soil. Watering of 100 cc water was done after sowing. Irrigation was done every 3, 7, and 14 days, depending on the object. In comparison with the corn moisture stress testing the difference in plant development could not be expressed with length measurements or green tip count.

[0150] An identification of wheat plant development stage was developed and is shown in Table 2, where stage 2 shows good development and therefore good moisture stress resistance, and stage 0 shows poor development and therefore poor moisture stress resistance.

TABLE-US-00002 TABLE 2 Stage description used in assessment of stress test in soil Stage Description of stage Stage 2 true leaves open and spread (third leaf clearly uncurled) Stage 1 True leaves still curled/rolled together but showing Stage 0 very small with no true leaves showing

[0151] Moisture and Salinity Stress Test in Soil

[0152] Salinity testing was done with wheat objects. The thermo-gradient table was filled with 5000 cc of potting soil (nutrient rich). 100 g per object was sown per block. Each block covered ⅓ of the thermo-gradient table, covering the full temperature range from 15 to 35° C. The seedbed was covered with 1,000 cc of potted soil.

[0153] The thermo-gradient caused moisture to evaporate at a rate which correlates with the gradient of temperature. With that, a gradient of drought was created overall. In the first two weeks the complete table was watered twice with 5 litres of a 0.01 M NaCl solution followed by a weekly watering for 5 weeks with 5 litres 0.4 M NaCl solution (sea water is 0.6 M NaCl). Evaluation was done by visual observation.

[0154] Testing was performed on seeds from sunflower, corn, wheat, lettuce and onion. These seeds were coated with film coats enriched with hydrolysed protein products which where synthetic or derived from organic matter of pea, potato, soybean, cotton or wheat. The type of moisture stress test varied per crop.

[0155] Materials

[0156] The effect of hydrolysed proteins was evaluated, amongst others, on corn, sunflower and wheat. With this selection of crops, a broad representation of different seeds and plant types was taken into account.

[0157] The tested objects and the origin of hydrolysed protein used in the additive are listed below.

[0158] Tested Hydrolyse Protein Products: [0159] Additive 1 (A1)—hydrolysed wheat protein [0160] Additive 2 (A2)—hydrolysed pea protein [0161] Additive 3 (A3)—hydrolysed potato protein [0162] Additive 4 (A4)—hydrolysed soybean protein [0163] Additive 5 (A5)—hydrolysed cotton protein

[0164] The application of the hydrolysed proteins on seeds was done via filmcoat which varied per crop. The hydrolysed proteins were added to commercially available filmcoats during mixing, resulting in a filmcoat “composition” which consisted for 10% out of hydrolysed proteins, in future reference this composition is referred to as filmcoat. Before application on seeds the filmcoats were diluted with water resulting in a filmcoat/water ratio 50/50 varying slightly per crop.

[0165] Drought Resistance Results

[0166] In Table 3 the total germ count is not affected by the film coat or the addition of hydrolysed proteins. The percentage of green tips from coleoptile is positively affected by the addition of hydrolysed proteins. This indicates that under the moisture stress, induced at a density of 1.024, the development of the seedling/plant is less negatively affected when the seeds are coated with a hydrolysed protein incorporated film coat.

TABLE-US-00003 TABLE 3 Results in corn under moisture stress conditions A % B % C % % Green tip Untreated corn seeds 0 10 88 51 Control treatment 0 8 92 46 A1 0 14 80 63 A2 2 14 82 76 A3 0 10 90 72 A4 0 30 70 84 A5 0 0 98 64

[0167] Plant stage evaluation of corn 14 days after sowing, with moisture density 1.024, classification using Table 1.

[0168] Similar results in drought resistance in general germination performance were also seen for sunflower seeds and shown in Table 4.

TABLE-US-00004 TABLE 4 Germination performance under osmotic pressure drought stress Average usable plants 10 days after sowing Control filmcoated 0 A1 86

[0169] Plant stage evaluation of sunflower seed germination on paper 14 days after sowing, with moisture density 1.008.

[0170] Moisture Stress Testing Wheat in Soil

[0171] Regulated drought stress test in soil was performed on wheat. The stages presented in Table 2 were used to describe the results as shown in Table 5. Initial results showed different reactions per used hydrolysed protein mostly in the general plant development.

[0172] The results presented in Table 5 show, that the interval of irrigation affects the development of the plants. The overall germination is not affected by the drought as all objects received the same amount of starting water. The untreated wheat object seems to be consistent in plant development, demonstrating a lesser or no negative reaction to the absence of moisture (i.e. where irrigation is poor) in comparison to the filmcoated control object.

TABLE-US-00005 TABLE 5 Results with wheat on soil with irrigation interval of 100 cc per 14 days % Stage 2 % Stage 1 % Stage 0 Filmcoated control 32 56 8 A2 60 40 0 A3 52 44 0 A4 52 48 0

[0173] Salinity Resistance

[0174] Results were obtained via the method described above. Table 6 shows the percentage usable wheat plants under saline conditions.

TABLE-US-00006 TABLE 6 Usable wheat plants under saline conditions Usable plants 35 days Usable plants 49 days after sowing (%) after sowing (%) Control filmcoated 5 3 A1 30 25 A2 70 65

[0175] Wheat plant evaluation on potted soil irrigated with 0.4M NaCl.

[0176] The results in Table 6 show a very clear and significant improvement in salinity resistance for the coatings of the present invention.

[0177] Positive effect on growth and plant development could be seen in moisture stress testing on corn, coated with all hydrolysed proteins, regulated moisture plant type testing on wheat, coated with all hydrolysed proteins, and plant type testing on a thermogradient table show similar positive effects. In general, a positive effect caused by the drought resistance additive on young plant development is seen under drought stress, thereby demonstrating improved drought stress tolerance.

[0178] It is to be understood that the invention is not to be limited to the details of the above embodiments, which are described by way of example only. Many variations are possible.