CN113893363A

CN113893363A - Combined soil disinfection method for preventing and treating soil-borne diseases

Info

Publication number: CN113893363A
Application number: CN202111196795.4A
Authority: CN
Inventors: 宋兆欣; 曹坳程; 王秋霞; 颜冬冬; 方文生; 李园
Original assignee: Institute of Plant Protection of Chinese Academy of Agricultural Sciences
Current assignee: Institute of Plant Protection of Chinese Academy of Agricultural Sciences
Priority date: 2021-10-14
Filing date: 2021-10-14
Publication date: 2022-01-07

Abstract

The invention relates to a combined soil disinfection method for preventing and treating soil-borne diseases, and belongs to the technical field of soil pollution treatment and environment restoration. The soil disinfection method comprises the following steps: spreading an organic carbon source in the pretreated soil, laying a drip irrigation system, covering with a film, carrying out drip irrigation with clear water, applying a DMDS liquid medicine during the drip irrigation period, and uncovering the film after disinfection. The invention effectively combines the ASD soil disinfection technology and the DMDS soil disinfection technology, improves the application range, enlarges the soil-borne disease prevention and control spectrum of the disinfection technology, can effectively prevent and control the soil-borne diseases of various crops on the basis of greatly reducing the using amount of the fumigant, reduces the cost of soil disinfection, promotes the growth of plants, improves the yield of the crops, and is an effective soil-borne disease prevention and control method which is good and suitable for popularization and use.

Description

Combined soil disinfection method for preventing and treating soil-borne diseases

Technical Field

The invention relates to the technical field of soil pollution treatment and environmental remediation, in particular to a combined soil disinfection method for preventing and treating soil-borne diseases.

Background

As a big agricultural country, China plays a very important role in guaranteeing the national civilian life. With the popularization and promotion of protected-field cultivation techniques in China, the occurrence of soil-borne diseases caused by soil-borne pathogens such as bacteria, fungi, nematodes, weeds and the like is getting more and more serious under the condition of continuous planting of a single crop variety. The problem of continuous cropping of soil also becomes a key problem which restricts the sustainable development of agricultural economy in China more and more. Soil disinfection technology is the most direct, effective and rapid method to effectively control soil-borne diseases caused by fungi, bacteria, nematodes, weeds, etc. (cajangtheng et al, 2013). The soil disinfection can efficiently solve the problem of continuous cropping of crops, reduce the accumulation of pathogenic microorganisms in the soil, reduce the occurrence probability of soil diseases and reduce the economic loss of farmers caused by soil-borne diseases. The soil disinfection technology mainly comprises chemical disinfection, biological fumigation disinfection, physical disinfection, ASD disinfection technology (ASD) and the like.

An anaerobic disinfection technology (ASD) as a non-chemical-environment-friendly soil disinfection technology can effectively prevent and control soil-borne diseases caused by fungi, bacteria, nematodes, weeds and the like. The ASD technology mainly comprises the following operation steps: adding a certain amount of liquid or solid organic carbon source, including liquid such as maltose syrup, grape residue collecting liquid, animal waste, biogas liquid, wheat bran, rice hulls and the like, uniformly applying the easily obtained leftover materials of agriculture and animal husbandry into soil, applying a drip irrigation system or irrigating sufficient water by sprinkling irrigation, finally covering the surface of the soil by using a plastic film and completely sealing for 2-15 weeks, ensuring that an anaerobic environment within an effective time range is provided within a plough layer range in the soil, and thus playing a role in effectively preventing and treating pathogens such as fungi, bacteria, nematodes, weeds and the like in the soil. However, the disinfection effect of the ASD technology is limited by various factors such as soil type, soil temperature, soil humidity, kind of carbon source addition, type of mulching film, soil disinfection time, and the like. The time requirement for ASD disinfection is relatively long, usually around 2-15 weeks; the difference of the organic carbon source additives of the ASD technology can influence the use effect of soil disinfection, and the instability of the effect influences the expansion application of the soil disinfection. The effective range of adding solid carbon sources such as wheat bran and organic fertilizers and adding liquid carbon sources such as syrup and alcohol into soil for ASD disinfection is usually within the range of 20-60cm on the soil surface. The use effect of the ASD technology is 50-85% of the disinfection effect on soil-borne pathogenic fungi, bacteria, nematodes and weeds.

Dimethyl disulfide (DMDS) has been officially registered as a soil fumigant in countries such as the united states, israel, turkey, libamon, jordan, egypt and morocco. A large number of studies at home and abroad find that the DMDS has high activity on various nematodes, but the activity of the DMDS on different soil-borne pathogenic fungi is greatly different, the effect is not ideal enough, and the field dosage of the 99.8 percent DMDS liquid for effectively preventing and killing fungi, bacteria and nematodes reaches 60-80g/m²The dosage is very large. Meanwhile, because the soil fumigant has different formulations, especially the factors needing to be considered when different fumigants are compounded and applied are more complex (such as direct mixing for chemical reaction, proper machinery, sequential application of medicines and the like), the methods suitable for the soil fumigant are different, and no soil fumigant application method suitable for the actual conditions according to local conditions exists in each region. Therefore, it is necessary to expand the application range of the DMDS disinfection technology, and avoid the mode effect difference and the popularization limitation of the ASD disinfection technology caused by the change of parameters such as weather, temperature, humidity, carbon source additives and the like.

Disclosure of Invention

The invention aims to provide a combined soil disinfection method for preventing and treating soil-borne diseases, which can effectively prevent and treat the soil-borne diseases of various crops on the basis of greatly reducing the using amount of a fumigant, reduce the cost of soil disinfection and improve the crop yield.

In order to solve the technical problems, the invention provides the following technical scheme:

a combined soil disinfection method for controlling soil-borne diseases, the method comprising the steps of:

spreading organic carbon source in soil, laying drip irrigation system, covering film, drip irrigation with clear water, applying DMDS liquid during drip irrigation, and uncovering the film after disinfection.

Preferably, the soil further comprises a pretreatment: the soil is rotary-tilled, and the rotary tillage depth of the soil is ensured to be 25-30cm without dead angles.

Preferably, the organic carbon source comprises one or more of wheat bran, rice hull or fermented chicken manure.

More preferably, the application amount of the organic carbon source is 500-1500 kg/mu.

Preferably, the DMDS liquid medicine is obtained by diluting 99.5 percent DMDS missible oil with water.

Preferably, the application amount of the DMDS liquid medicine is 15-30 kg/mu.

Preferably, the total water consumption of the drip irrigation clear water is 5-25 tons/mu.

Preferably, the time of covering the film is 7-21 days, and the time of uncovering the film is 7-21 days.

Preferably, the soil disinfection depth of the soil layer is 0-20 cm.

Preferably, the soil temperature for soil disinfection is 25.0-40.0 ℃.

The invention provides a combined soil disinfection method for preventing and treating soil-borne diseases, which creatively combines an ASD disinfection technology and a DMDS soil disinfection technology for use, improves the disinfection effect and the application range of the ASD and the DMDS, and greatly reduces the dosage of an organic carbon source and a DMDS medicament. Practice proves that the combined soil disinfection method can effectively prevent and treat soil-borne diseases of various crops such as cabbage, tomato, cucumber, strawberry, watermelon and the like, provides a green, low-toxicity and efficient soil disinfection technology suitable for crops such as vegetables, nurseries, Chinese herbal medicines and the like for broad farmers, and effectively solves the problem of the soil-borne diseases in agricultural production. Meanwhile, the method provided by the invention obviously reduces the consumption of the DMDS fumigant and the consumption of water, saves the cost of soil disinfection and the utilization of water resources, can promote the growth of crops, improves the yield of the crops, and is a good effective prevention and control method suitable for popularization and use.

Detailed Description

The invention provides a soil disinfection method by combining ASD and DMDS, which can enlarge the control effect of DMDS on pathogenic microorganisms such as bacteria, fungi, nematodes and the like, reduce the dosage of DMDS and reduce the fumigation cost of DMDS, and meanwhile, the ASD disinfection method is favorable for reducing DMDS into methyl mercaptan by key reductase (reductive nicotinamide adenine dinucleotide coenzyme I) generated under anaerobic condition, and then the methyl mercaptan finally generates CO under the action of a series of oxidases₂And sulfate, further reduce the residual amount of DMDS in soil, improve the environmental safety of DMDS use, and avoid the instability of the prevention and control effect of ASD disinfection method and DMDS disinfection method on soil diseases.

The invention provides a combined soil disinfection method for preventing and treating soil-borne diseases, which comprises the following steps:

In the invention, the soil also comprises pretreatment; the pretreatment comprises the following steps: the soil is rotary-tilled, and the rotary tillage depth of the soil is ensured to be 25-30cm without dead angles. The rotary tillage equipment is not particularly limited by the invention, and can be realized by adopting the conventional rotary tillage equipment in the field, and in the specific embodiment of the invention, the rotary tillage equipment is preferably a 25 horsepower tractor for hanging a rotary cultivator. In the invention, the organic carbon source preferably comprises one or more of wheat bran, rice hull or fermented chicken manure; the application amount of the organic carbon source is preferably 500-1500 kg/mu, and more preferably 800-1200 kg/mu. In the invention, the pretreatment can greatly reduce the use amount of the organic carbon source by 30-70% in the ASD disinfection process, thereby reducing the use cost of soil disinfection. The source of the organic carbon source is not particularly limited, and wheat bran, rice hull or fermented chicken manure which is locally conveniently obtained or is conventionally sold in the market can be selected according to environmental conditions.

In the present invention, the capillary spacing when the drip irrigation system is installed is preferably 30 to 50cm, more preferably 40 cm. After the drip irrigation system is laid, the working state of the drip irrigation system is preferably detected, and if the drip irrigation system is blocked or leaks, the drip irrigation system is replaced or debugged in time until the drip irrigation system works normally. The method for laying the drip irrigation system and detecting the drip irrigation system is not particularly limited, and a method which is conventional in the field can be adopted.

In the present invention, the thickness of the film is preferably 0.03 to 0.06mm, more preferably 0.04 mm. In the present invention, the time period of the covering film is preferably 7 to 21 days, more preferably 10 to 14 days. The material of the film is not particularly limited in the present invention, and in a specific embodiment of the present invention, the film is preferably a PE plastic film. In the invention, the film is required to completely cover the surface of the disinfection plot, so that all the working drip irrigation capillaries are uniformly laid under the film, and the periphery of the disinfection plot is tightly buried to isolate the gas exchange inside and outside the film.

In the invention, the DMDS liquid medicine is obtained by diluting 99.5 percent DMDS missible oil with water; the DMDS liquid medicine is preferably applied through a venturi applicator. The source of the DMDS missible oil is not particularly limited, and in the specific embodiment of the invention, the DMDS missible oil is preferably purchased from New chemical engineering Limited company in Linhai city, Zhejiang. In the invention, the application amount of the DMDS liquid medicine is preferably 15-30 kg/mu, and more preferably 20-25 kg/mu. The invention greatly reduces the dosage of DMDS while ensuring the effect of preventing and controlling pathogens such as bacteria, fungi, nematodes and the like, is beneficial to protecting the environment and improves the input-output ratio of agricultural materials. In the invention, the total water consumption of the drip irrigation clear water is preferably 5-25 tons/mu, and more preferably 10-20 tons/mu. The invention applies the DMDS liquid medicine during the drip irrigation period, can finish the drip irrigation water consumption required by ASD disinfection and DMDS soil disinfection at one time by using a drip irrigation system, saves the water consumption by more than 50 percent in the disinfection process, is favorable for improving the utilization rate of water resources and reduces the waste of the water resources.

In the invention, the time for opening the film is preferably 7 to 21 days, and more preferably 10 to 14 days. In the invention, the soil layer depth for soil disinfection is preferably 0-20cm, more preferably 5-18 cm; the soil temperature for soil disinfection is preferably 25.0 ℃ to 40.0 ℃, more preferably 33.5 ℃ to 36.6 ℃. In the invention, pesticide residue is detected through a germination experiment after the film uncovering and the aeration are finished, and the planting production of the next crop can be carried out after the detection is qualified.

In the invention, the raw materials and equipment are known products, and the conventional commercial products are adopted.

In order to further illustrate the present invention, the following embodiments are described in detail, but they should not be construed as limiting the scope of the present invention.

Example 1

1. Pretreatment of soil

Selecting a planting land for planting cucumbers, cleaning out cucumber residues and main roots after seedling pulling of the last-stubbled cucumbers, controlling soil humidity to be kept at 50%, then scattering cucumber ridges by using a hand tractor, then hanging a rotary cultivator by using a 25-horsepower tractor to carry out rotary tillage on the soil for 2 times, and ensuring that the rotary tillage depth of the soil is 25 cm.

2. Disinfection treatment

1) Uniformly spreading wheat bran on the surface of the treated soil according to the application amount of 500 kg/mu, and then using a 25-horsepower tractor to hang a rotary cultivator to completely carry out rotary tillage, so that the rotary tillage depth of the soil is 25cm and no dead angle exists.

2) A drip irrigation system (available from israel nomenclat, product specifications: the diameter of each capillary tube is 3mm, the flow rate of each drip irrigation system under normal pressure is 1.9L/h), the interval of the capillary tubes is 30cm, clear water is applied immediately after the drip irrigation system is installed to detect the working state of the drip irrigation system, and the drip irrigation system is replaced or debugged in time until the drip irrigation system works normally if a pipeline is blocked or leaks. Then, 0.04mm of PE plastic film (purchased from Shandong Shouguanglongxing plastics Co., Ltd.) is covered on the disinfection plot, the plastic film completely covers the surface of the disinfection plot, all the working drip irrigation capillaries are ensured to be uniformly laid under the film, and the periphery of the film is tightly buried by soil after the film covering is finished.

3) And opening a drip irrigation system for dripping water for 1 hour, and then dissolving the diluted 99.5 percent DMDS emulsifiable solution in water to apply the solution through a Venturi applicator, wherein the using amount of the DMDS liquid pesticide in a field is 15 kg/mu. And (3) continuously dropwise adding clear water after the DMDS drip irrigation is finished, wherein the clear water drip irrigation time is 4 hours, and the total water consumption is guaranteed to be 10 tons/mu. And (3) covering a film for sterilization for 7 days, uncovering the film after the sterilization is finished, and exposing the film to air for 7 days, wherein the soil temperature is 31.3 ℃ during the soil sterilization period. After the open air is finished, a 'germination test' is carried out to detect residues, and if no residues exist, the production of the next crop can be arranged.

Example 2

1. Pretreatment of soil

Selecting a planting land block for planting the cabbage, cleaning sundries such as cabbage residues and the like after seedling pulling of the cabbage in the previous stubble, controlling the soil humidity to be 60%, then using a 25 horsepower tractor to hang a rotary cultivator for carrying out rotary tillage on the soil for 1 time, and ensuring that the rotary tillage depth of the soil is 28 cm.

2. Disinfection treatment

1) And (3) uniformly spreading rice husks on the surface of the treated soil according to the application amount of 1000 kg/mu, and then using a 25-horsepower tractor to hang a rotary cultivator to carry out rotary tillage completely, so as to ensure that the rotary tillage depth of the soil is 30 cm.

2) A drip irrigation system (available from israel nomenclat, product specifications: the diameter of each capillary tube is 3mm, the flow rate of each drip irrigation system under normal pressure is 1.9L/h), the interval of the capillary tubes is 40cm, clear water is applied immediately after the drip irrigation system is installed to detect the working state of the drip irrigation system, and the drip irrigation system is replaced or debugged in time until the drip irrigation system works normally if the pipeline is blocked or leaks. Then, 0.04mm of PE plastic film (purchased from Shandong Shouguanglongxing plastics Co., Ltd.) is covered on the disinfection plot, the plastic film completely covers the surface of the disinfection plot, all the working drip irrigation capillaries are ensured to be uniformly laid under the film, and the periphery of the film is tightly buried by soil after the film covering is finished.

3) And opening a drip irrigation system for dripping water for 1.5h, and then dissolving the diluted 99.5 percent DMDS emulsifiable solution in water to apply the diluted DMDS emulsifiable solution through a Venturi applicator, wherein the using amount of the DMDS liquid pesticide in a field is 20 kg/mu. And (3) continuously dropwise adding clear water after the DMDS drip irrigation is finished, wherein the clear water drip irrigation time is 2 hours, and the total water consumption is ensured to be 15 tons/mu. The disinfection time of the covering film is 10 days, the covering film is uncovered after the disinfection is finished, the open air time is 12 days, and the soil temperature is 33.5 ℃ during the soil disinfection period. After the open air is finished, a 'germination test' is carried out to detect residues, and if no residues exist, the production of the next crop can be arranged.

Example 3

1. Pretreatment of soil

Selecting a planting land for planting tomatoes, cleaning tomato residues and main roots after seedling pulling of the previous-stubble tomatoes, and then hanging a rotary cultivator by using a 25 horsepower tractor to carry out soil rotary tillage for 3 times, thereby ensuring that the soil rotary tillage depth is 30 cm.

2. Disinfection treatment

1) And uniformly spreading the fermented chicken manure on the surface of the treated soil according to the application amount of 1500 kg/mu, and then using a 25-horsepower tractor to hang a rotary cultivator to carry out rotary tillage completely, so as to ensure that the rotary tillage depth of the soil is 25 cm.

2) A drip irrigation system (available from israel nomenclat, product specifications: the diameter of each capillary tube is 3mm, the flow rate of each drip irrigation system under normal pressure is 1.9L/h), the interval of the capillary tubes is 50cm, clear water is applied immediately after the drip irrigation system is installed to detect the working state of the drip irrigation system, and the drip irrigation system is replaced or debugged in time until the drip irrigation system works normally if the pipeline is blocked or leaks. Then, 0.04mm of PE plastic film (purchased from Shandong Shouguanglongxing plastics Co., Ltd.) is covered on the disinfection plot, the plastic film completely covers the surface of the disinfection plot, all the working drip irrigation capillaries are ensured to be uniformly laid under the film, and the periphery of the film is tightly buried by soil after the film covering is finished.

3) Opening a drip irrigation system for dripping water for 2 hours, and then dissolving the diluted 99.5 percent DMDS emulsifiable solution in water to apply the solution through a Venturi applicator, wherein the using amount of the DMDS liquid pesticide in a field is 30 kg/mu. And continuously dripping clear water after the DMDS drip irrigation is finished, wherein the time of dripping the clear water is 0.5h, and the total water consumption is ensured to be 25 tons/mu. The time for covering membrane to sterilize is 14 days, the membrane is uncovered after the sterilization is finished, the open air time is 21 days, and the soil temperature is 37.8 ℃ during the soil sterilization period. After the open air is finished, a 'germination test' is carried out to detect residues, and if no residues exist, the production of the next crop can be arranged.

Comparative example 1

After rotary tillage, 1000 kg/mu of wheat bran is applied, and then a rotary cultivator is hung by using a 25 horsepower tractor to complete rotary tillage. And (3) sealing watering, spraying a proper amount of water after rotary tillage, wherein the water spraying amount per mu is 15 tons, so that the soil surface layer is completely watered within the range of 5 cm.

Then, the film is covered by a TIF film with the thickness of 0.04mm and complete impermeability, furrows are dug around the sterilized land before the film is covered, then the TIF film is completely sealed by soil, the TIF film covering time is 30 days, and the ambient temperature is 25 ℃. After the disinfection is finished, the TIF film is uncovered, and the next crop can be planted after 7 days of air dissipation.

Comparative example 2

Selecting a planting land for planting cucumbers, deeply ploughing soil by using a 25 horsepower tractor, uniformly laying a dropper system capillary tube, and checking whether a main pipe and the capillary tube of the drip irrigation system work normally by using clear water after laying a pipeline. After the drip irrigation system works normally, clear water is firstly dripped for 2 hours, and during the period, the sterilized land is covered and sealed by using a plastic PE film.

And then, a drip irrigation system is used for applying the DMDS, the field dosage of the DMDS is 60 kg/mu, the DMDS soluble water agent is diluted by 30kg of clear water before use, and then the DMDS agent is uniformly applied to the ground through a Venturi applicator and a dropper system. After the DMDS liquid medicine is uniformly applied to the sterilized land, the drip irrigation is continuously opened, and clear water is dripped, wherein the clear water dosage is 30 tons/mu. And (4) uncovering the film for aeration for 7 days after the film is sealed for 15 days, and normally transplanting the cucumber seedlings after the drip irrigation pipe is removed.

Comparative example 3

The disinfection procedure and the plots were similar to comparative example 2, except that: a drip irrigation system is not required to be paved, and the Jixi SYD-2T soil is used for disinfection and injection, the agent is a chloropicrin preparation with the concentration of 99.8 percent, and the dosage is 30 kg/mu; covering the soil surface layer with PE film, uncovering the film after 7 days of covering, and then ventilating for 7 days. After the open air is finished, sensitive lettuce seedlings are used for carrying out a germination test to detect pesticide residues, and if no pesticide residues are left, next crop production can be arranged.

Comparative example 4

Blank control, soil was not treated at all.

Example 4

Evaluation of soil disinfecting Effect

The method of the embodiment 1 and the comparative examples 1 to 3 are utilized to respectively disinfect the soil of the same number of experimental fields in the northern service town of the cis-district in Beijing, after the soil disinfection is finished, a five-point sampling method is adopted to extract soil samples, namely 5 points are randomly extracted from the experimental fields according to the shape of Chinese character 'zhi' or Chinese character 'mi', the soil samples of the plough layer within the range of 0 to 20cm are collected at each point, after the samples are completely mixed, 500g of fresh soil samples are reserved and sent to a laboratory for separation and detection of pathogenic microorganisms, and the detection results are shown in the table 1.

The investigation content is separation detection of soil-borne pathogenic microorganisms (nematodes, fusarium and phytophthora) before and after disinfection, and pathogenic microorganisms subjected to experimental separation detection mainly comprise nematodes, fusarium and phytophthora. Meloidogyne spp (Meloidogyne spp.) was isolated by centrifugation (Liu Wei Shi, 2000). The soil-borne pathogen Fusarium (Fusarium spp.) was isolated using the Komada's method (Komada et al 1975). Phytophthora (Phytophthora spp.) was isolated using the Masago's method (Masago et al 1977).

The calculation formula of the control effect of the soil-borne pathogenic fungi is as follows:

TABLE 1 Effect of different methods on soil-borne pathogenic microorganisms

Note: each column of data is an average of 3 replicates, with the same letter following the average indicating no significant differences between treatments (p ═ 0.05)

Compared with a blank control, the method provided by the invention has the advantages that the quantity of soil-borne pathogens such as nematodes, phytophthora and fusarium in the soil is remarkably reduced, and the inhibition effects on the soil-borne pathogens are respectively 94.69%, 97.79% and 97.64%. The combined soil disinfection method has the advantages that the inhibition effect on the quantity of nematodes, phytophthora and fusarium is obviously higher than that of ASD disinfection treatment and DMDS disinfection treatment, and the combined soil disinfection method has strong killing activity on soil-borne pathogenic microorganisms, and the killing activity is obviously higher than that of ASD disinfection treatment and DMDS disinfection treatment which are used independently. The inhibiting effect of the ASD technology and the DMDS compound soil disinfection method on soil-borne pathogens is not dominant different from that of a chemical control fumigant chloropicrin.

Example 5

Cucumber planting trials were performed on the sterilized test fields described in example 4:

1. and after the disinfection is finished and before the cucumber is planted, applying 1000 kg/mu of organic fertilizer and 80 kg/mu of compound fertilizer required by the growth of next-stubble cucumber, making ridges after complete rotary tillage, and planting the cucumber. The cucumber varieties are as follows: zhongzhan No. 19, planting density is 3000 plants/mu, and ridge spacing of cultivated cucumber is 70 cm.

2. Measuring cucumber growth indexes at the initial stage, the middle stage and the later stage of field planting of cucumber respectively, wherein the indexes comprise: survival rate in seedling stage, root-knot index, cucumber yield, plant height of cucumber, stem thickness and seedling death rate. Tables 2 to 4 were obtained by measurement and calculation.

The cucumber survival rate investigation method comprises the following steps: and investigating 5-furrow cucumbers in each treatment area, recording the number of live seedlings and the number of dead seedlings of each furrow of cucumbers, and calculating the survival rate of the cucumbers in each treatment area.

In the early stage of field planting of cucumber, the plant height and stem thickness of the cucumber are respectively counted, and the investigation method comprises the following steps: 40 cucumbers were randomly selected for each site for data determination. Collecting cucumber plant samples of different processing areas in the seedling pulling stage of the cucumber to investigate the root knot index and the root disease index of the cucumber in the later growth stage of the cucumber. And (4) surveying 5 ridges in each treatment area, respectively counting the total number of cucumber plants in the 5 ridges and the number of dead seedlings, and then calculating the dead seedling rate.

The cucumber root knot index investigation period and the method are as follows: when pulling seedlings, 20 plants are selected in each treatment area, the whole root system of the cucumber is carefully dug out, and the root knot index of the cucumber is investigated. The root node is divided into 5 grades (0-4) according to the severity of the root node and the proportion of the root node in the whole root system:

0 to 0 percent, namely the root system is complete and has no root knots;

1-25%, namely, a small amount of root knots (the percentage of the root knots is less than 25%);

2-26-50%, namely, the root knots form a medium amount (accounting for 26-50% of the root system amount);

51-75 percent of 3, namely, more root knots (accounting for 51-75 percent of the root system quantity);

76% -100%, i.e. the root knot is extremely large and large (accounting for 76% -100% of the root system amount) (Desaeger et al, 2008).

The cucumber yield and income investigation method comprises the following steps: and (4) at least 2 ridges of fixed monitoring are selected in each treatment area, and the cucumber yield of each treatment area in each picking process is recorded. And finally, accumulating and converting the total yield per unit area of each treatment area.

In order to ensure the consistency of the data, all the data are measured on the spot by professional fixers; and data acquisition is carried out on the same day.

In addition, the survival rate (%) of cucumber plants is live seedling number/total seedling number × 100;

the dead plant rate (%) of cucumber plants is equal to the number of dead plants/total number of plants multiplied by 100;

the root-knot index Y% ((R1 + R2+ · + Rx)/(R × X) × 100), where Y is the root-knot index (%), Rx is the root-knot rating of the X-th strain, R is the highest-ranking value, and X is the total number of strains investigated.

The data analysis method comprises the following steps: all data were analyzed using SAS analysis software (SAS v.8.0for Windows). Necessary original data conversion is carried out before data analysis, and if the original data is less than 100, a square root value is taken for analysis; if the original data is larger than 100, the analysis should be carried out after the value (log 10). The data given in the tables below are raw data that were not converted. The Fisher's LSD method was used to test the significance of data differences (P ═ 0.05).

TABLE 2 influence of different soil sterilization treatment methods on survival rate of cucumber in seedling-returning period

Soil treatment technology	Average survival Rate (%)
		Comparative example 1	86.56a
Comparative example 2	88.98a
		Example 1	99.85a
Comparative example 3	98.46a
		Comparative example 4	97.98a

Note: each column of data is an average of 3 replicates, and if the letters are the same after the average, it indicates that the differences between treatments are not significant (p ═ 0.05).

As can be seen from Table 2, the difference between the survival rate of the cucumber in the seedling returning stage and the survival rate in the blank control area is not obvious in different soil disinfection treatment modes. The highest survival rate in the seedling stage of cucumber was 99.85% in the treatment area of the present invention, which is higher than the soil sterilization treatment of comparative example 1 and comparative example 2.

TABLE 3 influence of different soil disinfection treatment methods on cucumber plant height and stem thickness and root index

As shown in Table 3, the cucumber plants treated in the present application and comparative example 3 have a significant advantage in high stem thickness compared to comparative example 4, which is a blank control area. Comparative example 3 the plant height of cucumber in the treatment area was 82.51% higher than that in comparative example 4 in the control area, and the stem thickness was increased by 6.90%. The plant height of the cucumber in the treatment area reaches 187.6cm, the plant height is increased by 89.69% compared with that in a blank control area, the diameter of the stem is 1.25cm, and the plant height is increased by 7.75% compared with that in the blank control area. And the plant height of the cucumber of the example 1 is obviously higher than that of the cucumber of the comparative example 1 and the comparative example 2.

As can be seen from table 3, the cucumber yields after different sterilization treatments differed significantly. In the experiment, the lowest cucumber yield was 2.78kg/m compared to comparative example 4²All significantly lower than other treatments. The cucumber yields after the treatments of the present invention and comparative example 3 were 6.76kg/m, respectively²And 6.65kg/m²And the data difference between the two sterilization treatments is not significant. The cucumber yield after the soil treatment of the invention is significantly higher than that of comparative example 1 and comparative example 2.

Meanwhile, as can be seen from table 3, the root-knot index of comparative example 4 was the highest as high as 54.53% in the test. The root knot index and the root disease index of each soil after the disinfection treatment are both obviously lower than those of comparative example 4, but the difference between the disinfection treatments is not obvious. The cucumber root knot index of the soil disinfection treatment method of the invention is lower than that of the soil disinfection treatment method of the comparative example 1 and the comparative example 2.

TABLE 4 influence of different soil disinfection treatment techniques on the plant death rate of cucumber

Soil treatment technology	Mean plant death rate (%)
		Comparative example 1	12.32b
Comparative example 2	10.34b
		Example 1	2.45c
Comparative example 3	3.23c
		Comparative example 4	22.34a

As can be seen from Table 4, different soil disinfection treatment areas have certain difference in the later-stage plant death rate of the cucumbers. The cucumber seedling death rate in the blank control area reaches 22.34 percent, and the plant death rate is highest in all test treatments. Compared with a blank control, the treatment of the invention can obviously reduce the dead plant rate of cucumber (2.45%), and the dead plant rate of cucumber is obviously lower than that of the soil disinfection treatment methods of comparative example 1 and comparative example 2.

From the above examples, the results of field soil disinfection tests on cucumber crops show that: after the ASD disinfection method and the DMDS disinfection method are used in a combined mode, the quantity of the cucumber cultivation plot nematodes can be remarkably reduced, the later-stage root knot index and the root disease index of the cucumber are remarkably reduced, the harm of fungi such as soil-borne nematodes, fusarium and phytophthora is successfully inhibited, farmers are helped to improve the cucumber yield, and the income of the farmers is increased. The combined soil disinfection method provided by the invention is superior to the single use of the ASD disinfection technology and the DMDS soil disinfection technology in the aspects of preventing and treating cucumber soil-borne diseases, promoting plant growth, improving cucumber yield, increasing farmer income and the like. Therefore, the soil disinfection method provided by the invention can be popularized and applied as an effective prevention and control technology for preventing and controlling the nematode and the fungal diseases of the cucumber crops.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A combined soil disinfection method for controlling soil-borne diseases, comprising the steps of:

2. The soil disinfecting method of claim 1, wherein the soil further comprises a pretreatment: the soil is rotary-tilled, and the rotary tillage depth of the soil is ensured to be 25-30cm without dead angles.

3. The method of disinfecting soil as claimed in claim 1, wherein said organic carbon source comprises one or more of wheat bran, rice hulls, or fermented chicken manure.

4. The soil disinfecting method of claim 3, wherein the application amount of the organic carbon source is 500-1500 kg/acre.

5. The soil disinfecting method of claim 1, wherein the DMDS solution is obtained by diluting 99.5% DMDS emulsifiable concentrate with water.

6. The soil disinfecting method of claim 1, wherein the DMDS solution is applied in an amount of 15-30 kg/acre.

7. The soil disinfecting method of claim 1, wherein the total water usage of the drip irrigation clear water is 5-25 tons/acre.

8. The soil disinfecting method of claim 1, wherein the time period for covering the film is 7 to 21 days, and the time period for uncovering the film is 7 to 21 days.

9. The soil disinfecting method of claim 1, wherein the soil is disinfected to a depth of 0 to 20 cm.

10. The soil disinfecting method of claim 1, wherein the soil disinfected has a soil temperature of 25.0 ℃ to 40.0 ℃.