METHOD OF PREPARING CONDITIONER FOR PROTECTED AGRICULTURE ACIDIC SOIL WITH DISTILLERS' GRAINS AND USE

Abstract

The present invention provides a method of preparing a conditioner for protected agriculture acidic soil with distillers' grains and use of the conditioner. The method includes mixing distillers' grains with water, adjusting a pH to obtain adjusted distillers' grains, mixing the adjusted distillers' grains with an acid protease, and reacting under stirring at 45-50° C. for 22-26 hours to obtain a protease catalyzed substance, adjusting pH of the protease catalyzed substance, mixing with a cellulase, and reacting under stirring at 40-45° C. for 34-38 hours to obtain a cellulase catalyzed substance, filtering the cellulase catalyzed substance to obtain a filtrate, mixing the filtrate with a magnesium oxide (MgO) and then a calcium-containing substance, reacting to obtain a reactant, mixing the reactant with potassium sorbate and sucrose to obtain the conditioner for protected agriculture acidic soil.

Claims

1. A method of preparing a conditioner for protected agriculture acidic soil with distillers' grains, comprising the following steps: step 1): mixing distillers' grains with water, adjusting a pH to 4-4.2 to obtain adjusted distillers' grains; step 2): mixing the adjusted distillers' grains obtained in step 1) with an acid protease, and reacting under stirring at 45-50° C. for 22-26 h to obtain a protease catalyzed substance; step 3): adjusting pH of the protease catalyzed substance in step 2) to 4.6-4.8, mixing with a cellulase, and reacting under stirring at 40-45° C. for 34-38 h to obtain a cellulase catalyzed substance; and, step 4): filtering the cellulase catalyzed substance obtained in step 3) to obtain a filtrate, mixing the filtrate with a magnesium oxide (MgO) and then a calcium-containing substance, reacting to obtain a reactant, and mixing the reactant with potassium sorbate and sucrose to obtain the conditioner for protected agriculture acidic soil.

2. The method according to claim 1, wherein in step 1), a mass ratio of the distillers' grains to the water is 1:(3-5).

3. The method according to claim 1, wherein the distillers' grains have a particle size of 0.3-0.5 mm.

4. The method according to claim 2, wherein the distillers' grains have a particle size of 0.3-0.5 mm.

5. The method according to claim 1, wherein in step 2), every 10,000 enzyme activity units of the acid protease is added with an amount of 0.1-0.2% of the dry mass of the adjusted distillers' grains.

6. The method according to claim 1, wherein in step 3), every 10,000 enzyme activity units of cellulase is added with an amount of 0.2-0.5% of the dry mass of the reactant.

7. The method according to claim 1, wherein in step 4), a concentration of the MgO in the filtrate is 0.2-0.4 g/L.

8. The method according to claim 1, wherein: the calcium-containing substance comprises calcium oxide (CaO) and/or calcium carbonate (CaCO.sub.3); and, the calcium-containing substance is added with an amount of 25-40% of the mass of the filtrate.

9. The method according to claim 1, wherein in step 4), a volume of the potassium sorbate is 0.3-0.5% of that of the reactant.

10. The method according to claim 1, wherein in step 4), a mass of the sucrose is 0.1-0.3% of that of the reactant.

11. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 1 in improving a germination rate of a plant.

12. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 2 in improving a germination rate of a plant.

13. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 3 in improving a germination rate of a plant.

14. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 4 in improving a germination rate of a plant.

15. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 5 in improving a germination rate of a plant.

16. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 6 in improving a germination rate of a plant.

17. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 7 in improving a germination rate of a plant.

18. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 8 in improving a germination rate of a plant.

19. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 9 in improving a germination rate of a plant.

20. Use of a conditioner for protected agriculture acidic soil obtained by the method according to claim 10 in improving a germination rate of a plant.

Description

DETAILED DESCRIPTION

[0022] The present invention provides a method of preparing a conditioner for protected agriculture acidic soil with distillers' grains, including the following steps:

[0023] step 1): mixing distillers' grains with water, adjusting a pH to 4-4.2 to obtain adjusted distillers' grains;

[0024] step 2): mixing the adjusted distillers' grains obtained in step 1) with an acid protease, and reacting under stirring at 45-50° C. for 22-26 h to obtain a protease catalyzed substance;

[0025] step 3): adjusting pH of the protease catalyzed substance in step 2) to 4.6-4.8, mixing with a cellulase, and reacting under stirring at 40-45° C. for 34-38 h to obtain a cellulase catalyzed substance; and,

[0026] step 4): filtering the cellulase catalyzed substance obtained in step 3) to obtain a filtrate, mixing the filtrate with a magnesium oxide (MgO) and then a calcium-containing substance, reacting to obtain a reactant, and mixing the reactant with potassium sorbate and sucrose to obtain the conditioner for protected agriculture acidic soil.

[0027] In the present invention, the source of the distillers' grains is not particularly limited, and conventional distillers' grains left after wine making may be used. In the present invention, the distillers' grains are preferably sorghum distillers' grains or corn distillers' grains. In the present invention, the distillers' grains preferably have a particle size of 0.3-0.5 mm.

[0028] In the present invention, a mass ratio of the distillers' grains to the water is preferably 1:(3-5). In the present invention, potassium hydroxide or acetic acid is preferably used to adjust the pH to 4.6-4.8.

[0029] In the present invention, every 10,000 enzyme activity units of the acid protease is preferably added with an amount of 0.1-0.2% of the dry mass of the adjusted distillers' grains. The present invention has no particular limitation on the source of the acid protease, and a commercially available product conventional in the art may be used. In the present invention, the adjusted distillers' grains are mixed with the acid protease, and the reaction is preferably carried out under stirring at 45-50° C. for 24 h. In the present invention, every 10,000 enzyme activity units of cellulase is preferably added with an amount of 0.2-0.5% of the dry mass of the reactant. The present invention has no special limit on the source of the cellulase, and a conventional commercial product may be used. In the present invention, the protease catalyzed substance is mixed with the cellulase, and the reaction is preferably carried out under stirring at 40-45° C. for 36 h.

[0030] The present invention has no specific limitation on filtering and conventional conditions of filtering an enzyme catalyzed substance can be employed.

[0031] In the present invention, a concentration of the MgO in the filtrate is preferably 0.2-0.4 g/L, and more preferably 0.3 g/L. In the present invention, the calcium-containing substance preferably includes calcium oxide (CaO) and/or CaCO.sub.3, and the calcium-containing substance is added with an amount of 25-40% of the mass of the filtrate. In the present invention, the filtrate is mixed with the MgO, and then mixed with the calcium-containing substance and reacted with no bubbles coming out from the calcium-containing substance as a sign of complete reaction. In the present invention, a volume of the potassium sorbate is preferably 0.3-0.5% of that of the reactant. In the present invention, a mass of the sucrose is preferably 0.1-0.3%, and more preferably 0.2% of that of the reactant.

[0032] The present invention further provides use of the conditioner for protected agriculture acidic soil obtained by the foregoing technical solution in improving germination rate of a plant. In the present invention, the plant preferably includes garland chrysanthemum or spinach. The use method of the conditioner for protected agriculture acidic soil is not particularly limited in the present invention, and a conventional use method of a soil conditioner can be used.

[0033] The technical solutions provided by the present invention are described in detail below with reference to the examples, but the technical solutions cannot be understood as limiting the protection scope of the present invention.

Example 1

[0034] 5 kg of sorghum distillers' grains were pulverized with a pulverizer to obtain a powder with a particle size of 0.3 mm. 25 kg of water was added and stirred well. At this point, the measured pH was 3.6 and the salinity was 0.02%. 5.8 g of KOH powder was added to adjust the pH to 4.1. 0.5 ml of 150,000 U/g acid protease (Shengxia brand, APRL type) was added, mixed and stirred at 50° C. for 24 h. After reaction, the amino acid content of the reaction solution was determined to be 4.7%. KOH was added till the pH of the reaction solution reached 4.6. 2 g of 50,000 U/g cellulase (Heshibi Biotechnology Co., Ltd.) was added for treatment at an average temperature of 42° C. for 36 h. 8 g of MgO powder was added and fully dissolved. CaCO.sub.3 powder was added until there was no bubble coming out. At this point, the reaction solution had a pH of 5.2 and a salinity of 0.13%. 7.5 g of potassium sorbate and 50 g of sucrose were added respectively and preparation of a repairing agent was completed.

[0035] The protected agriculture soil which was used for 6 consecutive years was selected for an experiment of germination of garland chrysanthemum. The soil for the experiment was in Sujiatun District of Shenyang City. The soil had significant acidification problems due to continuous cultivation of leafy vegetables for years, and a pH of 4.6 (ratio of water to soil being 1:2.5) which made it no longer capable of growing garland chrysanthemum. The above soil repairing agent was diluted 100 times and used as irrigation water for the experiment which was applied in a total amount of 3.5-5 m.sup.3/mu in 2-3 times of drip irrigation after spray irrigation to avoid flood irrigation. 10 days later, the soil pH and germination was measured. A control experiment used conventional irrigation water with an amount of irrigation water and field management and the like the same as those with the repairing agent. The grown garland chrysanthemum was a conventional variety on the market with a germination rate of 89%. The results are shown in Table 1.

TABLE-US-00001 TABLE 1 Experimental results of effect of the repairing agent prepared from sorghum distillers' grains on garland chrysanthemum germination. pH Treatment Before treatment Day 10 Germination rate CK 4.6 4.8 10% Soil repairing agent 4.6 5.9 73%

Example 2

[0036] 3 kg of corn distillers' grains were pulverized to obtain a powder with a particle size of 0.2 mm. 15 kg of water was added and stirred well. At this point, the measured pH was 3.3 and the salinity was 0.03%. 7.8 g of KOH powder was added to adjust the pH to 4.0. 0.3 ml of 150,000 U/g acid protease (Shengxia brand, APRL type) was added, mixed and stirred at 48° C. for 24 h. After reaction, the amino acid content of the reaction solution was 3.9%. KOH was added till the pH of the reaction solution reached 4.4. 1.2 g of 50,000 U/g cellulase (Heshibi Biotechnology Co., Ltd.) was added for treatment at an average temperature of 42° C. for 36 h. 6 g of MgO powder was added and fully dissolved. CaCO.sub.3 powder was added until there was no bubble coming out. At this point, the reaction solution had a pH of 5.1 and a salinity of 0.17%. 4.5 g of potassium sorbate and 30 g of sucrose were added respectively to obtain a soil repairing agent prepared from corn distillers' grains.

[0037] The protected agriculture soil which had been used for continuous farming for 11 years in Liaozhong District of Shenyang City was used for an experiment to test an improvement effect on spinach. The pH of the soil before treatment was 4.9 (ratio of water to soil being 1:2.5). The soil repairing agent prepared from the corn distillers' grains was used for the germination experiment which specifically carried out as follows: the soil for the experiment was screened through a 2 mm sieve and used as a soil for seedling. A seedbed was made with evenly laid soil. Seeds were laid at a depth of 0.5 cm and then covered with original soil. The repairing agent was diluted 100 times and used as irrigation water which was evenly sprayed. A plastic film was applied for coverage. Emergence was observed from time to time. After 7 days, the overall germination rate was calculated. The plant for the experiment was spinach which was commercially available with a germination rate of 94%. The results are shown in Table 2.

TABLE-US-00002 TABLE 2 Experimental results of effect of the repairing agent prepared from corn distillers' grains on spinach germination. pH Treatment Before treatment Day 10 Germination rate CK 4.9 4.7 <5% Soil repairing agent 4.9 5.5 62%

[0038] Through the experiments of effects of improvement of acidic soil on the two common leaf vegetables, it can be found that the soil conditioner produced after the treatment on sorghum and corn distiller's grains of the present invention can increase the pH of the protected agriculture acidic soil and increase the germination rates of the two leaf vegetables, the garland chrysanthemum and the spinach compared with control, showing a significant technical advantage. At the same time, the product can be directly applied with irrigation water, thereby reducing additional input in improving protected agriculture acidic soil, which showed production convenience.

[0039] The above descriptions are merely preferred implementations of the present invention. It should be noted that a person of ordinary skill in the art may further make several improvements and modifications without departing from the principle of the present invention, but such improvements and modifications should be deemed as falling within the protection scope of the present invention.