A biological soil amendment composition, formulation, and methods of making and using the same

Abstract

The present application relates to the field of biotechnology, and particularly relates to a biological bottom modification composition, a preparation and a preparation method and application thereof.The biological bottom modification composition provided by the present application comprises Bacillus subtilis YXSY-01 bacterial powder, Sphingomonas aquatilis HD-01 bacterial liquid, bentonite, oyster shell powder, attapulgite, zeolite powder, raw fish bone powder and water.The biological bottom modification composition and the preparation provided by the present application have the ability to degrade the feces of cultured animals and reduce the content of nitrite.The composition and the preparation can reduce the accumulation of the feces of cultured animals in a culture pond, reduce the content of nitrite, purify the water quality of the culture pond and reduce the incidence of cultured animals.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biotechnology, in particular to a biological bottom modification composition, preparation and preparation method and application thereof. BACKGROUND

[0002] In aquaculture production, the utilization rate of aquatic animals to feed is low, only a small part of the feed can be effectively utilized, and most of them are in the form of excrement-poop discharged outside. The greater the amount of excrement generated, the more significant the adverse effects on the aquaculture water. In aquaculture production, the content of excrement in the aquaculture water is one of the factors that determine the quality of the aquaculture water environment. At present, aquaculture is developing towards high-density and intensive factory farming. This type of farming is based on high-density farming and artificially controls each link of farming to achieve the purpose of high yield and high efficiency. Due to high-density farming and large amount of feed, a large amount of excrement is produced in the farming process, which greatly increases the pollution pressure of the water body, causes serious water pollution, destroys the ecological balance of the pond, and causes pathogenic bacteria to breed and diseases of farmed animals to break out.

[0003] In the middle and late stages of small shed shrimp farming, due to the excessive use of high-protein feed, the nitrogen element cycle is blocked, a large amount of inorganic nitrogen source is accumulated in the water body, and the content of nitrite in the water body is too high, which seriously affects the health of aquatic animals and causes great loss to farming. The commonly used methods for removing nitrite in water include physical method, chemical method and biological method. The physical method mainly uses physical adsorption and water exchange method, but these methods have the problems of slow effect, easy to cause stress and cannot fundamentally solve the problem. The chemical method for removing nitrite mainly includes chemical barrier agent and strong oxidizing agent, but it is difficult to reduce the effect of nitrite. The biological method mainly uses nitrifying bacteria and denitrifying bacteria to gradually convert nitrite into nitrogen, but this method has the characteristics of slow growth rate, low treatment efficiency and difficulty in preservation in actual use.

[0004] Therefore, there is an urgent need for a method that can effectively and simultaneously solve the accumulation of animal excrement and the degradation of nitrite. SUMMARY

[0005] The purpose of the present application is to provide a biological bottom modification composition, preparation and preparation method and application thereof to solve the problems existing in the prior art. The biological bottom modification granules provided by the present application have the ability to degrade the excrement of farmed animals and reduce the content of nitrite, can reduce the accumulation of excrement of farmed animals in the aquaculture pond, purify the water quality of the aquaculture pond, and ultimately achieve the purpose of reducing the incidence of farmed animals.

[0006] To achieve the above purpose, the present application provides the following solutions:

[0007] This invention provides a bio-based substrate modification composition comprising the following components in parts by weight:

[0008] 0.3-1.7 parts Bacillus subtilis YXSY-01 bacterial powder, 0.2-2 parts Sphingomonas aquatilis HD-01 bacterial solution, 30-50 parts bentonite, 30-40 parts oyster shell powder, 1-3 parts attapulgite, 2-6 parts zeolite powder, 1-1.5 parts raw fish bone meal, and 1.5-4.5 parts water;

[0009] The preservation number of Bacillus subtilis YXSY-01 is GDMCC No: 64078; the preservation number of Sphingomonas aquaticus HD-01 is GDMCC No: 64330.

[0010] Preferably, the bio-modified bottom composition comprises the following components in parts by weight:

[0011] 1 part Bacillus subtilis YXSY-01 bacterial powder, 1.5 parts aquatic sphingomonas HD-01 bacterial solution, 45 parts bentonite, 40 parts oyster shell powder, 3 parts attapulgite, 4 parts zeolite powder, 1 part raw fish bone powder and 4.5 parts water.

[0012] Alternatively, 1 part Bacillus subtilis YXSY-01 bacterial powder, 1.5 parts aquatic sphingomonas HD-01 bacterial solution, 43 parts bentonite, 40 parts oyster shell powder, 3 parts attapulgite, 5.5 parts zeolite powder, 1.5 parts raw fish bone powder, and 4.5 parts water.

[0013] Preferably, the viable count of Bacillus subtilis YXSY-01 in the Bacillus subtilis YXSY-01 powder is 1.0 × 10⁻⁶. 10 ~5.0×10 10 CFU / g;

[0014] The viable count of *Sphingomonas aquaticus* HD-01 in the bacterial culture was 1.0 × 10⁻⁶. 7 ~2.0×10 8 CFU / g;

[0015] The oyster shell powder is oyster shell powder with a diameter of 2~3mm.

[0016] This invention provides the application of the above-described bio-bottom modification composition in the preparation of bio-bottom modification formulations.

[0017] The present invention provides a biological bottom modification formulation comprising the above-described biological bottom modification composition.

[0018] Preferably, the dosage form of the biological bottom-modifying agent is granules.

[0019] The application provides a preparation method of the biological bottom improvement agent.

[0020] The mixture of the Bacillus subtilis YXSY-01 bacterial powder and the Sphingomonas aquatilis HD-01 bacterial liquid is mixed with the oyster shell powder to obtain a mixture.

[0021] The mixture is mixed with the bentonite, the zeolite powder, the raw fish bone powder, the attapulgite and water to obtain the biological bottom improvement agent.

[0022] The application provides an application of the biological bottom improvement composition or the biological bottom improvement agent in degrading excrement and / or reducing nitrite content in a water body.

[0023] The application provides a method for degrading excrement and / or reducing nitrite content in a water body, which comprises the step of applying the biological bottom improvement agent to the water body.

[0024] Preferably, the application amount of the biological bottom improvement agent is 1 kg / time / mu; and the interval time of application is 5 days.

[0025] The application discloses the following technical effects:

[0026] The biological bottom improvement composition provided by the application comprises Bacillus subtilis YXSY-01 bacterial powder, Sphingomonas aquatilis HD-01 bacterial liquid, bentonite, oyster shell powder, attapulgite, zeolite powder, raw fish bone powder and water. The biological bottom improvement composition and the preparation provided by the application have the abilities of degrading excrement of cultured animals and reducing nitrite content. The composition and the preparation can reduce the accumulation of excrement of cultured animals in a culture pond, reduce the nitrite content, purify the water quality of the culture pond, and finally achieve the purpose of reducing the morbidity of the cultured animals. DETAILED DESCRIPTION

[0027] The various exemplary embodiments of the application are now described in detail. It should be understood that the detailed description is not intended to limit the application to the particular form described herein, but is to serve as an exemplification of certain aspects of the application. The application is outlined in the following detailed description with reference to the figures.

[0028] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, where a range of values is provided, it is understood that each intervening value, to the upper and lower limit of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of these smaller ranges can independently be included or excluded in the range, and are also encompassed by the application, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included.

[0029] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict, the present specification will control.

[0030] Various modifications and changes can be made to the specific embodiments of the present application described herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from the description and examples herein. The description and examples are illustrative only.

[0031] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having", "contains", "containing", or variations thereof, are intended to be open-ended and do not exclude other components, features, or steps.

[0032] Unless otherwise required by context, as used herein the term "about" means ±10% of the value stated.

[0033] Example 1

[0034] A biological soil improvement granule, the formula is as follows (i.e. the raw materials required for producing 1 kg of biological soil improvement granule):

[0035] Bacillus subtilis YXSY-01 bacterial powder 10 g, aquaspora HD-01 bacterial liquid 15 g, bentonite 450 g, oyster shell powder with a diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 40 g, fresh fish bone powder 10 g, and purified water 45 g.

[0036] Bacillus subtilis YXSY-01 has been preserved in the Guangdong Microbial Culture Collection Center on November 27, 2023, the address of preservation is: No. 59 Building, 5th Floor, Institute of Microbiology, Guangdong Academy of Sciences, 100 Middle Martyrs Road, Guangzhou, the preservation number is: GDMCC No: 64078;

[0037] Sphingomonas aquatilis HD-01 has been preserved in Guangdong Microbial Culture Collection Center on May 8, 2024, and the address of the preservation is: 5th floor, No. 59 Building, Guangzhou Xianlie Middle Road 100, Institute of Microbiology, Guangdong Academy of Sciences, the preservation number is: GDMCC No: 64330.

[0038] The preparation method of Bacillus subtilis YXSY-01 powder is as follows:

[0039] (1) Preparation of Bacillus subtilis YXSY-01 fermentation broth: according to the preparation method of the patent with publication number CN118703394B, Bacillus subtilis YXSY-01 fermentation broth is obtained;

[0040] (2) Preparation of Bacillus subtilis YXSY-01 powder: 10wt% calcium hydrogen phosphate is added to Bacillus subtilis YXSY-01 fermentation broth, and spray drying is carried out, the inlet air temperature of spray drying is 156℃, and the outlet air temperature is 105℃, to obtain Bacillus subtilis YXSY-01 powder, the viable cell count of Bacillus subtilis YXSY-01 in the Bacillus subtilis YXSY-01 powder is between 1.0×10 10 ~5.0×10 10 CFU / g.

[0041] The preparation method of Sphingomonas aquatilis HD-01 bacterial solution is as follows:

[0042] (1) Preparation of Sphingomonas aquatilis HD-01 fermentation broth: according to the preparation method of the patent with publication number CN118703394B, Sphingomonas aquatilis HD-01 fermentation broth is obtained;

[0043] (2) Preparation of Sphingomonas aquatilis HD-01 bacterial solution: Sphingomonas aquatilis HD-01 fermentation broth is passed through a 100-mesh screen to obtain Sphingomonas aquatilis HD-01 bacterial solution, the viable cell count of Sphingomonas aquatilis HD-01 in the Sphingomonas aquatilis HD-01 bacterial solution is between 1.0×10 7 ~2.0×10 8 CFU / g.

[0044] The preparation method of biological bottom improvement granules is as follows:

[0045] Step 1: Mix 10g of Bacillus subtilis YXSY-01 powder and 15g of Sphingomonas aquatilis HD-01 bacterial solution uniformly to obtain a mixed solution.

[0046] Second step: the mixture obtained in the first step is sprayed on 400 g of oyster shell powder with a diameter of 2-3 mm and mixed evenly.

[0047] Third step: 450 g of bentonite, 40 g of zeolite powder, 10 g of fresh fish bone powder and 30 g of attapulgite are sequentially added to the mixture obtained in the second step and stirred and mixed evenly.

[0048] Fourth step: 45 g of purified water is added to the mixture obtained in the third step, and after being mixed thoroughly, it is put into a granulator to form granules, obtaining the biological bottom improvement granules. The color of the biological bottom improvement granules is light yellow, and the probiotic content is 1.0 x 10 8 CFU / g-5.0 x 10 8 CFU / g, and has a wide range of applications.

[0049] Comparative Example 1

[0050] A kind of biological bottom improvement granules, the formula is as follows (i.e. the raw materials required for producing 1 kg of biological bottom improvement granules):

[0051] 10 g of commercially available 100 billion Bacillus subtilis (purchased from Dayu Biology) powder, 15 g of commercially available 100 billion Bacillus licheniformis (purchased from Dayu Biology) powder, 450 g of bentonite, 400 g of oyster shell powder with a diameter of 2-3 mm, 30 g of attapulgite, 40 g of zeolite powder, 10 g of fresh fish bone powder and 45 g of purified water.

[0052] The preparation method of the biological bottom improvement granules is carried out according to the following steps:

[0053] First step: 10 g of commercially available 100 billion Bacillus subtilis (purchased from Dayu Biology) powder and 15 g of commercially available 100 billion Bacillus licheniformis (purchased from Dayu Biology) powder are mixed evenly to obtain a mixture.

[0054] Second step: the mixture obtained in the first step is sprayed on 400 g of oyster shell powder with a diameter of 2-3 mm and mixed evenly.

[0055] Third step: 450 g of bentonite, 40 g of zeolite powder, 10 g of fresh fish bone powder and 30 g of attapulgite are sequentially added to the mixture obtained in the second step and stirred and mixed evenly.

[0056] Fourth step: 45 g of purified water is added to the mixture obtained in the third step, and after being mixed thoroughly, it is put into a granulator to form granules, obtaining the biological bottom improvement granules. The color of the biological bottom improvement granules is light yellow, and the probiotic content is 1.0 x 10 8 CFU / g-5.0 x 10 8 CFU / g.

[0057] Example 1 and Comparative Example 1 to prepare the biological bottom modification granules to treat the water body of the South American white shrimp culture

[0058] The information of the treated ponds is shown in Table 1.

[0059] Table 1 Information of the treated ponds

[0060] The treatment period is 2 months, starting from the 30th day of the South American white shrimp culture, using once every 5 days, a total of 6 times, and the dosage of the biological bottom modification granules is 1 kg per mu each time.

[0061] The fecal content and nitrite content of the water samples before and after treatment were determined, and the results are shown in Table 2. Among them, the detection method of fecal content in water body is to take the lower water body of the pond (5 cm above the bottom of the pond), filter with neutral filter paper, add 10 times distilled water to the filter residue, and rinse (the speed of the shaking table is 80 rpm, and the time is 10 min). After rinsing, filter with neutral filter paper and repeat rinsing three times. Dry the feces, put the filter residue into a ventilated drying oven, dry at 55°C to constant weight. The detection method of nitrite is referred to "GB / T 2367-2016".

[0062] Table 2 Investigation results after treatment

[0063]

[0064] As can be seen from Table 2, compared with the biological bottom modification granules prepared by Comparative Example 1, the treatment of the biological bottom modification granules prepared by Example 1 can significantly reduce the nitrite content and fecal content in the water body of the South American white shrimp culture.

[0065] Example 2

[0066] A kind of biological bottom modification granules, the formula is as follows (i.e. the raw materials required for producing 1 kg of biological bottom modification granules):

[0067] Bacillus subtilis YXSY-01 bacteria powder 10 g, aquasheamannol HD-01 bacteria liquid 15 g, bentonite 430 g, oyster shell powder with a diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 55 g, fresh fish bone powder 15 g and pure water 45 g.

[0068] Bacillus subtilis YXSY-01 bacteria powder and aquasheamannol HD-01 bacteria liquid are prepared by Example 1.

[0069] The preparation method of the biological bottom modification granules is as follows:

[0070] First step: 10 g of Bacillus subtilis YXSY-01 powder and 15 g of aqueous sphingan were mixed uniformly to obtain a mixed solution.

[0071] Second step: The mixed solution obtained in the first step was sprayed on 440 g of oyster shell powder with a diameter of 2-3 mm and mixed uniformly.

[0072] Third step: In the mixture obtained in the second step, 430 g of bentonite, 40 g of zeolite powder, 10 g of fresh fish bone powder and 30 g of attapulgite were sequentially added and stirred and mixed uniformly.

[0073] Fourth step: 45 g of pure water was added to the mixture obtained in the third step, and after being mixed thoroughly, it was put into a granulator to form granules, thereby obtaining the biological bottom improvement granules. The biological bottom improvement granules have a light yellow color, a probiotic content of 1.0×10 8 CFU / g-5.0×10 8 CFU / g, and a wide range of applications.

[0074] Effect example 2: Effect test of the biological bottom improvement granules prepared in example 2 on the treatment of California bass aquaculture water bodies

[0075] The information of the treated fish ponds is shown in Table 3.

[0076] Table 3: Information of the treated fish ponds

[0077]

[0078] The treatment period was 3 months, and the biological bottom improvement granules were used from the 100th day of cultivation, once every 5 days, a total of 18 times, and the dosage of the biological bottom improvement granules was 1 kg / acre each time.

[0079] The fecal content and nitrite content of the water samples were determined before and after the treatment, and the investigation results are shown in Table 4. Among them, the detection method of the fecal content in the water body is to take the lower water body of the pond (5 cm above the bottom of the pond), filter with neutral filter paper, add 10 times distilled water to the filtered residue, and rinse (the speed of the shaker is 80 rpm, and the time is 10 min), after rinsing, filter with neutral filter paper, and repeat rinsing three times. Dry the feces, put the residue into a ventilated drying oven, dry at 55℃ until the weight is constant. The detection method of nitrite refers to "GB / T 2367-2016".

[0080] Table 4: Investigation results after treatment

[0081]

[0082] As shown in Table 4, the biological bottom improvement granules provided by the application can significantly reduce the content of nitrite and feces in the water body.

[0083] Example 3

[0084] Experimental group 1: Bacillus subtilis YXSY-01 bacterial powder 10 g, aquasheamannidium HD-01 bacterial liquid 15 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 55 g, fresh fish bone powder 15 g, and purified water 45 g.

[0085] Experimental group 2: Bacillus subtilis YXSY-01 bacterial powder 25 g, aquasheamannidium HD-01 bacterial liquid 0 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 55 g, fresh fish bone powder 15 g, and purified water 45 g.

[0086] Experimental group 3: Bacillus subtilis YXSY-01 bacterial powder 0 g, aquasheamannidium HD-01 bacterial liquid 25 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 55 g, fresh fish bone powder 15 g, and purified water 45 g.

[0087] Experimental group 4: Bacillus subtilis YXSY-01 bacterial powder 20 g, aquasheamannidium HD-01 bacterial liquid 5 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 30 g, zeolite powder 55 g, fresh fish bone powder 15 g, and purified water 45 g.

[0088] Experimental group 5: Bacillus subtilis YXSY-01 bacterial powder 10 g, aquasheamannidium HD-01 bacterial liquid 15 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 35 g, zeolite powder 55 g, fresh fish bone powder 10 g, and purified water 45 g.

[0089] Experimental group 6: Bacillus subtilis YXSY-01 bacterial powder 10 g, aquasheamannidium HD-01 bacterial liquid 15 g, bentonite 430 g, oyster shell powder with diameter of 2-3 mm 400 g, attapulgite 25 g, zeolite powder 55 g, fresh fish bone powder 20 g, and purified water 45 g.

[0090] Bacillus subtilis YXSY-01 bacterial powder and aquasheamannidium HD-01 bacterial liquid were prepared according to Example 1.

[0091] Granulation was performed according to the granulation method of Example 2.

[0092] The bottom layer water body (5 cm above the bottom of the pond) of different ponds of Micropterus salmoides was taken, and was divided into 1000 mL beakers, each beaker containing 800 mL of liquid. After standing for 30 min, 1 g of the bottom improvement granules was added to each group, and was stood for 72 h. The nitrite content of the water body was detected, and each group had 3 parallel samples.

[0093] The processed fish pond information is shown in Table 5.

[0094] Table 5 Processed fish pond information

[0095]

[0096] The processing period is 3 months, and the use starts from the 100th day of breeding, once every 5 days, a total of 18 times, and the use amount of each time of the biological bottom improvement granules is 1 kg / mu.

[0097] The fecal content and nitrite of the water sample before and after the treatment are determined, and the investigation results are shown in Table 6. Among them, the detection method of the fecal content in the water body is to filter with neutral filter paper, add 10 times of distilled water to the filtered residue, and rinse (the speed of the shaking table is 80 rpm, and the time is 10 min), after the rinsing is completed, filter with neutral filter paper, and repeat the rinsing three times. Dry the feces, put the residue into a ventilated drying box, dry at 55℃ until the weight is constant. The detection method of nitrite refers to “GB / T 2367-2016”.

[0098] Table 6 Investigation results after treatment

[0099]

[0100] As known from Table 6, the overall effect of the experimental group 1 is the best, followed by the experimental group 4 changing the use amount of the two strains, followed by the experimental group 2 and the experimental group 3 omitting one of the strains, and the experimental group 5 and the experimental group 6 changing the use amount of the auxiliary materials. As can be seen, the use amount, combination of the two strains and the use amount of the auxiliary materials will affect the effect after the treatment. However, within the scope provided by the present application, the effect is the best.

[0101] The above-described embodiments are only to describe the preferred modes of the present application, and do not limit the scope of the present application, and various modifications and improvements of the technical solutions of the present application made by those skilled in the art without departing from the design spirit of the present application shall fall within the protection scope determined by the claims of the present application.

Claims

1. The application of a bio-bottom-modifying composition in the preparation of bio-bottom-modifying formulations, characterized in that, The composition comprises the following components in parts by weight: 0.3-1.7 parts Bacillus subtilis YXSY-01 bacterial powder, 0.2-2 parts Sphingomonas aquatilis HD-01 bacterial solution, 30-50 parts bentonite, 30-40 parts oyster shell powder, 1-3 parts attapulgite, 2-6 parts zeolite powder, 1-1.5 parts raw fish bone meal, and 1.5-4.5 parts water; The preservation number of Bacillus subtilis YXSY-01 is GDMCC No: 64078; the preservation number of Sphingomonas aquaticus HD-01 is GDMCC No: 64330.

2. The application according to claim 1, characterized in that, The composition comprises the following components in parts by weight: 1 part Bacillus subtilis YXSY-01 bacterial powder, 1.5 parts aquatic sphingomonas HD-01 bacterial solution, 45 parts bentonite, 40 parts oyster shell powder, 3 parts attapulgite, 4 parts zeolite powder, 1 part raw fish bone powder and 4.5 parts water. Alternatively, 1 part Bacillus subtilis YXSY-01 bacterial powder, 1.5 parts aquatic sphingomonas HD-01 bacterial solution, 43 parts bentonite, 40 parts oyster shell powder, 3 parts attapulgite, 5.5 parts zeolite powder, 1.5 parts raw fish bone powder, and 4.5 parts water.

3. The application according to claim 1, characterized in that, The viable count of Bacillus subtilis YXSY-01 in the Bacillus subtilis YXSY-01 powder was 1.0 × 10⁻⁶. 10 ~5.0×10 10 CFU / g; The viable count of *Sphingomonas aquaticus* HD-01 in the bacterial culture was 1.0 × 10⁻⁶. 7 ~2.0×10 8 CFU / g; The oyster shell powder is oyster shell powder with a diameter of 2~3mm.

4. A biological bottom-modifying agent, characterized in that, Includes the composition described in claim 1.

5. The biological bottom-modifying agent according to claim 4, characterized in that, The biological bottom-modifying agent is in granule form.

6. The method for preparing the biological bottom-modifying agent according to claim 4, characterized in that, Includes the following steps: The mixture of Bacillus subtilis YXSY-01 bacterial powder and Sphingomonas aquaticis HD-01 bacterial solution is mixed with the oyster shell powder to obtain a mixture; The mixture is combined with the bentonite, the zeolite powder, the raw fish bone powder, the attapulgite clay, and the water to obtain the biological bottom modifier.

7. The application of the biological bottom conditioner as described in claim 4 or 5 in the degradation of feces and / or reduction of nitrite content in water bodies.

8. A method for degrading feces and / or reducing the nitrite content in water, characterized in that, The step includes applying the biological bottom modifier as described in claim 4 or 5 into the water body.

9. The method according to claim 8, characterized in that, The application rate of the biological bottom improvement agent is 1 kg / time / acre; the application interval is 5 days.

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