CN112425477A - Rice seedling raising bed soil, application and seedling raising method - Google Patents

Abstract

The invention discloses rice seedling raising bed soil, application and a seedling raising method. The rice seedling bed soil provided by the invention comprises rice field soil, an elemental fertilizer, a bactericide and carbonized straws and/or rice hulls, is simple in components, does not need to be thoroughly decomposed, and is matched with the following seedling method: firstly, rice sprouts are placed in rice seedling bed soil, a pH buffering agent is adopted to adjust the pH of the rice seedling bed soil to be 4.5-5.5, and then a nutrient solution is additionally sprayed during the growth period of the leaf age of rice seedlings, wherein the method specifically comprises the step of spraying a simple substance nitrogen fertilizer and a simple substance potassium fertilizer when the leaf age of the rice seedlings reaches 1.5-2.0; when the leaf age of rice seedlings reaches 2.0-3.5 leaves, spraying an inter-seedling bactericide and a simple substance nitrogen fertilizer; after the leaf age of rice seedlings reaches 3.5-4.0 leaves, hardening the seedlings and spraying a simple substance nitrogen fertilizer and an insect-resist agent; and (5) hardening off the seedlings and transplanting. Can realize guaranteeing the seedling quality, practice thrift manufacturing cost, satisfy the production demand, can realize emerging fast.

Description

Rice seedling raising bed soil, application and seedling raising method

Technical Field

The invention relates to the technical field of agriculture, in particular to rice seedling bed soil, application and a seedling method.

Background

At present, rice seedling raising substrates are widely researched, and most of components of the rice seedling raising substrates are straws, coconut chaff, livestock manure, vermiculite, perlite and the like as raw materials, but the rice seedling raising substrates have limitations, firstly, the materials need to be fully decomposed, the materials which are not fully decomposed cannot be used for preparing seedbed soil, and the seedling death phenomenon is frequent due to the period; secondly, the cost is high, and a decomposition agent is added in the decomposition process, the price is not high compared with that of a mature decomposition agent, and although a good decomposition effect can be achieved, the production cost is increased; thirdly, materials are not easily obtained, taking vermiculite as an example, the vermiculite is a natural inorganic mineral, only 6 countries produce all over the world, and the materials are not easily obtained; fourthly, the existing rice seedling raising acidity regulation mainly uses sulfuric acid, belongs to high-risk chemical medicines, and is toxic and harmful. Fifthly, water after acidification is introduced to water a seedbed, seedlings are easy to burn, leaves are dry, and certain destructiveness is brought to production.

The current rice seedling bed soil has complex preparation steps, is extremely difficult to master in production, has low operability and high cost. Therefore, the preparation and application method of the simple rice seedling bed soil is particularly important.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to provide rice seedling bed soil, application of the rice seedling bed soil in rice seedling and a seedling method of the rice seedling bed soil.

The invention is realized by the following steps:

in a first aspect, the invention provides rice seedling raising bed soil, which comprises rice field soil, an elemental fertilizer, a bactericide, carbonized straws and/or rice hulls.

The preparation method of the carbonized straws comprises the step of calcining the straws at 160-280 ℃ for 150-200 min to obtain the carbonized straws, wherein the straws comprise corn straws and/or rice straws. The soil consumption of the seedling bed soil can be reduced after the carbonized straws are added into the rice seedling bed soil, so that the risk of soil-borne diseases is reduced, and meanwhile, the carbonized straws have strong adsorbability and can effectively adsorb nutrients to become carriers of the nutrients.

The rice hull is a shell outside the rice. The rice husk consists of outer glume, inner glume, glume protecting and small spike stalk, and the top of the outer glume is grown with hair in the shape of temple. The rice hull is composed of some coarse sclerenchyma cells, the thickness of the rice hull is about 24-30 microns, the rice hull is rich in cellulose, lignin and silicon dioxide, and the content of fat and protein is low. After rice hulls are added into the rice seedling bed soil, the soil porosity can be improved, the soil air permeability is increased, the temperature of the seedling bed is improved, and seedling rooting is facilitated.

In an alternative embodiment, the rice seedling bed soil comprises rice field soil, carbonized straws, rice hulls, an elemental fertilizer and a bactericide; the sum of the mass of the carbonized straws and the rice hulls is equal to the mass of the rice field soil. The mass ratio of the elemental fertilizer to the rice seedling bed soil is 1-2: 1000, such as 1:1000, 1.5:1000 or 2: 1000; the mass ratio of the bactericide to the rice seedling bed soil is 0.5-1.5: 10000, such as 0.5:10000, 1:10000 or 1.5: 10000.

In an alternative embodiment, the elemental fertilizer comprises one or a combination of more than two of urea, diammonium hydrogen phosphate or potassium sulfate.

In an optional embodiment, the elemental fertilizer comprises, by mass, 1: 1-4: 1-6 parts of urea, diammonium hydrogen phosphate and potassium sulfate; preferably 1:2.5: 2.5.

In an alternative embodiment, the volume ratio of the carbonized straw to the rice hull is 1: 0.5 to 3; preferably 1: 1.

In an alternative embodiment, the bactericide comprises carbendazim and/or thiram.

Preferably, the mass ratio of the carbendazim to the thiram is 1: 0.1 to 2; further preferably 1: 1.

In a second aspect, the present invention provides a use of the soil for a bed for raising rice seedlings according to the aforementioned embodiment for raising rice seedlings.

In a third aspect, the invention provides a seedling raising method using the rice seedling raising bed soil according to the above embodiment, which includes the steps of placing rice sprouts in the rice seedling raising bed soil, adjusting the pH of the rice seedling raising bed soil to 4.5-5.5 by using a pH buffering agent, and then additionally spraying a nutrient solution during the growth period of the leaf age of rice seedlings. In the seedling bed period, the pH of the rice seedling growing environment is usually 4.5-5.5, and in order to obtain a stable rice seedling growing environment, the pH of the rice seedling bed soil needs to be controlled to be 4.5-5.5.

When the leaf age of rice seedlings reaches 1.5-2.0, spraying a simple substance nitrogen fertilizer and a simple substance potassium fertilizer; when the leaf age of rice seedlings reaches 2.0-3.5 leaves, spraying an inter-seedling bactericide and a simple substance nitrogen fertilizer; after the leaf age of rice seedlings reaches 3.5-4.0 leaves, hardening the seedlings and spraying a simple substance nitrogen fertilizer and an insect-resist agent; and (5) hardening off the seedlings and transplanting.

When the leaf age of rice seedlings reaches 1.5-2.0, endosperm nutrients in rice seeds are about to be exhausted, nutrients need to be supplied from the outside, the production is called a weaning period, fertilizers need to be additionally added, compared with nitrogen fertilizers and potassium fertilizers, phosphate fertilizers are not easy to run off, and for the rice seedlings just entering the weaning period, the nitrogen fertilizers and the potassium fertilizers are selectively added; when the leaf age of the rice reaches 2.0-3.5 leaves, the nutrient consumption in the seeds is completed in the period, and nutrients need to be obtained from the outside, the nitrogen fertilizer is selectively supplemented, the cultivation of strong seedlings is facilitated, the seedling quality is improved, meanwhile, the disease easily occurs in the period, and a bactericide needs to be applied in time; hardening off and transplanting are needed after the leaf age of the rice reaches 3.5-4.0 leaves, nitrogen fertilizer needs to be further supplemented to strengthen the seedlings so as to ensure the hardening off and transplanting quality, and meanwhile, insect damage is threatened after transplanting, so that an insect-resist agent needs to be sprayed.

In an optional embodiment, before the rice bud seedlings emerge, the water content of the soil of the rice seedling bed is adjusted to be 70% -80%; after the rice sprouts emerge and before hardening, the water content of the soil of the rice seedling bed is adjusted to be 30-40%.

Before emergence, it is desirable to ensure that the soil has a high moisture content, for example from 70% to 80%, in order to facilitate emergence. After seedling emergence, the moisture content is not easy to be too high, and is preferably kept at 30% -40%, the moisture content is too high, diseases are easy to occur, roots are not easy to breathe in bed soil, and the growth of the roots is inhibited. In addition, in production, seedling cultivation is generally finished from the middle and last ten days of 4 months to the middle and last ten days of 5 months, at the moment, the external temperature gradually rises, the humidity of seedling cultivation soil is too high, seedling leaves grow excessively, and seedling blight occurs, so that seedling cultivation needs to be performed in a dry way in production.

Preferably, the water content is adjusted using a pH buffer.

Preferably, the pH buffer comprises a citric acid pH buffer.

Preferably, the preparation method of the citric acid pH buffering agent comprises the step of measuring 0.2mol/L disodium hydrogen phosphate solution and 0.1mol/L citric acid solution according to the volume ratio of 51.5: 48.5.

The acid liquor has stable performance, can buffer strong acid and alkali substances, and provides a stable growth environment for rice seedlings. At present, in production, the sulfuric acid is prepared by adopting sulfuric acid, belongs to a high-risk chemical agent, has high use risk and toxicity, and the prepared acidity is unstable and is extremely difficult to master in production.

In an alternative embodiment, the nutrient solution is sprayed by first preparing a homogeneous solution of the desired spray components and then spraying the solution all at once.

Preferably, the elemental nitrogen fertilizer and the elemental potassium fertilizer comprise an aqueous solution containing ammonium sulfate and potassium dihydrogen phosphate.

Preferably, the concentration of ammonium sulfate in the aqueous solution containing ammonium sulfate and potassium dihydrogen phosphate is 2-3 g/L, and the concentration of potassium dihydrogen phosphate is 2-3 g/L.

Preferably, the interspinous bactericide and elemental nitrogen fertilizer comprise a solution containing benazolin and ammonium sulfate formulated using a pH buffer as a solvent.

Preferably, the solution containing the benazolin and the ammonium sulfate, which is prepared by using the pH buffering agent as the solvent, comprises 2-2.5 g/L of the benazolin and the ammonium sulfate concentration is 7-8 g/L.

Preferably, the elemental nitrogen fertilizer and insect control agent comprise a solution containing ammonium sulfate and cola nut emulsion formulated using a pH buffer as a solvent.

Preferably, the concentration of ammonium sulfate in the solution containing ammonium sulfate and the omethoate missible oil prepared by using the pH buffering agent as the solvent is 5-6 g/L, and the concentration of the omethoate missible oil is 0.4-0.5 g/L.

Preferably, the preparation method of the citric acid pH buffering agent comprises the step of measuring 0.2mol/L disodium hydrogen phosphate solution and 0.1mol/L citric acid solution according to the volume ratio of 51.5: 48.5.

Preferably, when the leaf age of the rice seedlings reaches 2.0-3.5 leaves, the frequency of spraying the inter-seedling bactericide and the elemental nitrogen fertilizer is at least two times.

Preferably, when the leaf age of the rice seedlings reaches 3.0 leaves, the inter-seedling bactericide and the elemental nitrogen fertilizer are sprayed.

The invention has the following beneficial effects:

the invention provides rice seedling raising bed soil which comprises rice field soil, an elemental fertilizer, a bactericide and carbonized straws and/or rice hulls, and compared with the existing seedling raising materials, the rice seedling raising bed soil is easy to obtain raw materials and low in cost. The raw materials of the bed soil for raising the seedlings of the rice do not need to be fermented thoroughly, so that the production problem caused by insufficient fermentation is avoided, and the bed soil for raising the seedlings of the rice is prepared and used as it is, thereby saving time and labor.

Compared with the existing seedling culture method, the seedling culture bed soil pH is adjusted by selecting the pH buffering agent, so that the preparation of acid liquor by adopting sulfuric acid is avoided, the production risk is greatly reduced, and the seedling culture method is safe to people and livestock. In addition, different nutrient solutions are designed in the seedling raising method in a targeted manner at different leaf age stages of rice seedlings, so that the occurrence of soil-borne diseases is reduced, the soil consumption of a seedbed is reduced, and the straws can be effectively returned to the field under the action of the nutrient solutions.

Compared with the prior art, the seedling raising method disclosed by the invention has the advantages that the bed soil dosage can be reduced by adding the carbonized straws into the rice seedling raising bed soil, so that the risk of introducing grass seeds into the bed soil is reduced, the occurrence of phytotoxicity of the seedling bed is reduced, and the dosage of the herbicide is reduced.

Compared with the existing seedling raising method, the rice seedling raising bed soil is adopted, and the nutrient solution with different components is sprayed at different stages of rice seedlings, so that the rice seedlings can quickly emerge, and the operating efficiency of rice seedling raising is obviously improved.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The features and properties of the present invention are described in further detail below with reference to examples.

Example 1

1.1 preparation of carbonized straw

And (3) calcining the rice hulls at 200 ℃ for 180min to obtain carbonized straws.

1.2 preparing the soil of the bed for growing rice seedlings

250kg of rice field soil and 250kg of a mixture of carbonized straws and rice hulls, wherein the volumes of the carbonized straws and the rice hulls are equal, 500kg of rice seedling raising bed soil doped with the carbonized straws and the rice hulls is obtained by mixing, 0.16kg of urea, 0.4kg of diammonium hydrogen phosphate, 0.4kg of potassium sulfate, 20g of carbendazim (pure amount) and 20g of thiram (pure amount) are added into the rice seedling raising bed soil, and the mixture is uniformly mixed.

1.3 preparation of pH buffer (solution A)

Weighing Na₂HPO₄Adding into water with pH 7.0, dissolving sufficiently to obtain 0.2mol/L Na₂HPO₄And (3) solution. Citric acid was weighed and added to water having a pH of 7.0, and sufficiently dissolved to obtain a 0.1mol/L citric acid solution. According to Na₂HPO₄The volume ratio of the solution to the citric acid solution is 51.5:48.5, and acid solution with pH of 5.0 is prepared.

1.4 preparing nutrient solution

Preparation of aqueous solution (solution B) of ammonium sulfate and potassium dihydrogen phosphate: adding ammonium sulfate and potassium dihydrogen phosphate into clear water to make the concentrations of ammonium sulfate and potassium dihydrogen phosphate both 2.5 g/L.

Preparation of aqueous solution (solution C) of oxaziridine and ammonium sulfate: the A solution is used as a solvent, and benazolin and ammonium sulfate are added, so that the final concentration of the benazolin is 2.25g/L, and the final concentration of the ammonium sulfate is 7.5 g/L.

Preparation of aqueous solution of ammonium sulfate and gala missible oil (solution D): and (3) adding the omethoate missible oil and ammonium sulfate by taking the solution A as a solvent, so that the final concentration of the omethoate missible oil is 0.45g/L, and the final concentration of the ammonium sulfate is 5.5 g/L.

1.5 growing seedlings

1.5.1 evenly putting the rice seedling bed soil prepared in the step 1.2 into a seedling tray, enabling the rice seedling bed soil to be flush with the edge of the seedling tray, and thoroughly watering the seedling bed soil in the seedling tray by using the solution A through a spraying method, wherein the spraying can be stopped when the water content reaches 70-80%. Uniformly sowing 20 prepared rice sprouts in a tray in 2019, 4 and 15 days, covering the rice sprouts with a plastic film, compacting the rice sprouts with a roller, fully pressing the rice sprouts into bed soil, removing the film, starting covering the bed soil for the second time, controlling the thickness of the bed soil for the second time to be 0.7cm, and spraying the liquid A after uniform covering, wherein the liquid A can be sprayed discontinuously to achieve better effect, and the discontinuous time can be controlled within 1 hour. After the liquid A is sprayed, the sunlight film can be covered, and seedlings can emerge.

1.5.2 after the leaf age of rice seedling reaches 1.0 leaf, control and educate seedling tray in the water content 30 ~ 40%, can adopt A liquid, carry out the spraying, should adjust the atomizer shower nozzle, make spun liquid be the radiation state, can fully sneak into the seedbed soil like this in with liquid to avoid spouting on the blade.

When the leaf age of 1.5.3 rice seedlings reaches 1.5 leaves, the liquid B is adopted for spraying, and a sprayer nozzle is adjusted to enable the sprayed liquid to be in a radiation state, so that the liquid can be fully mixed into the bed soil, and the spraying to the leaves is avoided.

1.5.4 when the age of rice seedling reaches 2.0 leaves, the C liquid is sprayed, and the sprayer nozzle should be adjusted to make the sprayed liquid in radiation state, so that the liquid can be fully mixed into the soil of the seedling bed to avoid spraying onto the leaves.

When the leaf age of 1.5.5 rice seedlings reaches 3.0 leaves, the C liquid is adopted for spraying, and a sprayer nozzle is adjusted to enable the sprayed liquid to be in a radiation state, so that the liquid can be fully mixed into the bed soil, and the spraying to the leaves is avoided.

1.5.6 when the age of rice seedling reaches 3.5 leaves, it is sprayed once with D liquid to prevent and control leaf miner. After hardening off, transplanting can be carried out, and the rice seedling plants obtained after hardening off require the height of mechanically transplanted rice seedlings to be more than 15cm and the leaf age to be more than 3.5 in production, according to the overall actual standard reaching situation of 20 rice seedlings, in order to realize unified operation, 5-month and 11-day in 2019 is determined as the transplanting day, namely the seedling raising period is 26 days, and the plant height and the leaf age of the 20 rice seedling transplanting days are counted, as shown in table 1.

1.5.7 before transplanting, use Qianjin to comprehensively prevent and control weeds.

TABLE 1 size comparison Table for leaf age and plant height at transplanting date of 20 rice seedlings obtained in example 1

As can be seen from table 1, when the rice seedling raising bed soil provided by the embodiment is used for raising rice seedlings, 20 rice seedlings all meet the transplanting requirement through a seedling raising period of 26 days, and the average plant height of the 20 rice seedlings is 15.38cm and the average leaf age is 3.62 leaves, which completely meets the transplanting requirement.

The above-mentioned determination of the seedling growing period of 26 days is to ensure that all of the 20 rice seedlings reach the transplanting standard, and as can be seen from table 1, the rice seedling with the number of 10 grows most slowly. The growth conditions in the seedling raising period are shown in table 2.

Table 2 shows the seedling growth period comparison table of seedling with number 10

Example 2

The difference between this example and example 1 is that the soil of the seedling bed does not contain the carbonized straws and contains rice husk with the amount of 250m³。

Example 3

The difference between this example and example 1 is that the soil of the seedling bed does not contain rice hulls and contains carbonized straws with the dosage of 250m³。

Example 4

The difference between the embodiment and the embodiment 1 is that the dosage of the urea, the diammonium phosphate and the potassium sulfate in the elemental fertilizer used for the soil of the seedling bed is 0.15kg, 0.3kg and 0.3 kg.

Example 5

The difference between the embodiment and the embodiment 1 is that the dosage of the urea in the elemental fertilizer used by the soil of the seedling bed is 0.26kg, the dosage of the diammonium phosphate is 0.37kg, and the dosage of the potassium sulfate is 0.37 kg.

Example 6

The difference between the embodiment and the embodiment 1 is that the dosage of carbendazim in the bactericide used for the soil of the seedling bed is 12.5g, and the dosage of thiram is 12.5 g.

Example 7

The difference between the present example and example 1 is that the amount of carbendazim in the bactericide used for the soil of the seedling bed was 37.5g, and the amount of thiram was 37.5 g.

Example 8

The difference between the example and the example 1 is that the amount of carbonized straw used for the bed soil for raising rice seedlings is 160m³The rice husk is 80m³。

Example 9

The difference between the example and the example 1 is that the amount of the carbonized straw used for the soil of the bed for raising seedlings is 160m³The rice husk is 480m³。

Comparative example 1

The difference between the comparative example and the example 1 is that the soil of the seedling bed does not contain the rice husk and the carbonized straws, and contains vermiculite, grass carbon and perlite with the volume of 50m respectively³，100m³，100m³。

Experimental example 1

In this experimental example, the seedling bed soils provided in example 1, example 2, example 3 and comparative example 1 were used to grow 20 rice seedlings according to the seedling growing process provided in example 1, and three rice seedlings were randomly selected per group to measure the sizes of the seedlings after a seedling growing period of 26 days, and the results are shown in the following table.

Table 3 time table of seedling raising process of example 1, example 2, example 3 and comparative example 1

Compared with the comparative example 1, the components used in the experimental example 1, the experimental example 2 and the experimental example 3 are simple and easy to obtain, farmers can obtain the seedlings by themselves in production, vermiculite, perlite and the like are not needed to be used for preparing the bed soil, the production time is saved, the investment is reduced, the seedlings cultured by the bed soil for seedling culture provided by the experimental examples 1, 2 and 3 reach the transplanting standard after the seedlings are cultured for 26 days, and the seedlings obtained by the comparative example 1 cannot be used for transplanting.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The rice seedling raising bed soil is characterized by comprising rice field soil, an elemental fertilizer, a bactericide and carbonized straws and/or rice hulls, wherein the carbonized straws are prepared by calcining straws at 160-280 ℃ for 150-200 min, and the straws comprise corn straws and/or rice straws.

2. A bed soil for raising rice seedlings according to claim 1, wherein the bed soil for raising rice seedlings comprises paddy field soil, carbonized straw, rice husk, elemental fertilizer and bactericide; the sum of the mass of the carbonized straws and the rice hulls is equal to the mass of the rice field soil; the mass ratio of the elemental fertilizer to the rice seedling bed soil is 1-2: 1000; the mass ratio of the bactericide to the rice seedling bed soil is 0.5-1.5: 10000.

3. A seedling raising bed soil for rice as claimed in claim 1 or 2, wherein the elemental fertilizer comprises one or a combination of two or more of urea, diammonium hydrogen phosphate or potassium sulfate.

4. A seedling raising bed soil for rice as claimed in claim 3, wherein the elemental fertilizer comprises, by mass, 1: 1-4: 1-6 parts of urea, diammonium hydrogen phosphate and potassium sulfate; preferably 1:2.5: 2.5.

5. A rice seedling raising bed soil as claimed in claim 1 or 2, wherein the volume ratio of the carbonized straw to the rice husk is 1: 0.5 to 3; preferably 1: 1.

6. The rice seedling raising bed soil as claimed in claim 1 or 2, wherein the bactericide comprises carbendazim and/or thiram;

preferably, the mass ratio of the carbendazim to the thiram is 1: 0.1 to 2; further preferably 1: 1.

7. A method for growing seedlings of rice, comprising applying the soil to a growing bed of rice seedlings according to any one of claims 1 to 6.

8. A seedling raising method using the rice seedling raising bed soil as claimed in any one of claims 1 to 6, comprising the steps of placing rice sprouts in the rice seedling raising bed soil, adjusting the pH of the rice seedling raising bed soil to 4.5 to 5.5 using a pH buffering agent, and then additionally spraying a nutrient solution during the growth of the leaf age of rice seedlings:

when the leaf age of rice seedlings reaches 1.5-2.0, spraying a simple substance nitrogen fertilizer and a simple substance potassium fertilizer; when the leaf age of rice seedlings reaches 2.0-3.5 leaves, spraying an inter-seedling bactericide and a simple substance nitrogen fertilizer; after the leaf age of rice seedlings reaches 3.5-4.0 leaves, hardening the seedlings and spraying a simple substance nitrogen fertilizer and an insect-resist agent; and (5) hardening off the seedlings and transplanting.

9. A seedling raising method according to claim 8, wherein the water content of the soil of the seedling raising bed of the rice is adjusted to 70-80% before the rice sprouts emerge; after the rice sprouts emerge and before hardening, adjusting the water content of the soil of a rice seedling bed to be 30-40%;

preferably, the water content is adjusted using a pH buffer;

preferably, the pH buffer comprises a citric acid pH buffer;

preferably, the preparation method of the citric acid pH buffering agent comprises the step of measuring 0.2mol/L disodium hydrogen phosphate solution and 0.1mol/L citric acid solution according to the volume ratio of 51.5: 48.5.

10. A seedling raising method according to claim 8, characterized in that in the process of spraying the nutrient solution, firstly, the required spraying components are prepared into a uniform solution and then are sprayed at one time;

preferably, the elemental nitrogen fertilizer and the elemental potassium fertilizer comprise aqueous solution containing ammonium sulfate and potassium dihydrogen phosphate;

preferably, the concentration of ammonium sulfate in the aqueous solution containing ammonium sulfate and potassium dihydrogen phosphate is 2-3 g/L, and the concentration of potassium dihydrogen phosphate is 2-3 g/L;

preferably, the interspinous bactericide and elemental nitrogen fertilizer comprise a solution containing benazolin and ammonium sulfate formulated using a pH buffer as a solvent;

preferably, the solution which is prepared by using the pH buffering agent as the solvent and contains the benazolin and the ammonium sulfate comprises 2-2.5 g/L of the benazolin, and the concentration of the ammonium sulfate is 7-8 g/L;

preferably, the elemental nitrogen fertilizer and insect control agent comprise a solution containing ammonium sulfate and cola nut emulsion formulated using a pH buffer as a solvent;

preferably, the concentration of ammonium sulfate in the solution containing ammonium sulfate and the omethoate missible oil prepared by using the pH buffering agent as the solvent is 5-6 g/L, and the concentration of the omethoate missible oil is 0.4-0.5 g/L;

preferably, the preparation method of the pH buffering agent comprises the steps of measuring 0.2mol/L disodium hydrogen phosphate solution and 0.1mol/L citric acid solution according to the volume ratio of 51.5: 48.5;

preferably, when the leaf age of the rice seedlings reaches 2.0-3.5 leaves, the frequency of spraying the inter-seedling bactericide and the elemental nitrogen fertilizer is at least two times;

preferably, when the leaf age of the rice seedlings reaches 3.0 leaves, the inter-seedling bactericide and the elemental nitrogen fertilizer are sprayed.