Compound substrate formula for preventing and treating clubroot of cruciferae crops and application of compound substrate formula

Abstract

The invention relates to the technical field of plant disease prevention and treatment, and discloses a compound substrate for preventing and treating clubroot of cruciferae crops, which is prepared from the following raw materials in volume ratio: 10-30% of peat, 50-70% of calcined oyster shell powder and 10-30% of coconut shell charcoal. According to the formula of the compound substrate, the peat, the calcined oyster shell powder and the coconut shell biomass charcoal are combined according to a specific proportion, all the components play a synergistic role, the calcined oyster shell powder and the coconut shell biomass charcoal can adsorb pathogenic bacteria spores through a physical barrier, the pH value of soil can be adjusted to be slightly alkaline, growth of plasmodiophora brassicae is inhibited, and the soil quality is improved. Meanwhile, a good living environment is provided for beneficial microorganisms, and the biological antagonism is enhanced; peat provides good water and fertilizer retention performance, the peat and other components jointly construct a rhizosphere environment which is beneficial to crop growth and not beneficial to pathogenic bacterium reproduction, synergistic interaction of a single-function material combination is achieved, and the problem that in the prior art, single-function materials lack the synergistic effect is solved.

Description

Technical Field

[0001] The invention relates to the technical field of plant disease prevention and control, in particular to a composite matrix formula for preventing and controlling clubroot disease of cruciferous crops and application thereof. Background Art

[0002] Chinese cabbage clubroot is caused by Brassica rapa, a fungus belonging to the subphylum Mastigomycota. The pathogen prefers a warm and humid environment, with a suitable temperature range of 9-30°C and an optimal temperature of 19-25°C; the optimal soil water holding capacity is 70%, the relative humidity is 70-98%, and the optimal soil pH is 5.4-6.5[1][2]. The pathogen overwinters in soil, diseased debris, and uncomposted manure as dormant spores, and becomes the primary source of infection in the field. The pathogen can survive in the soil for 6-7 years[4](Yang Peiwen et al., 2002). In soil infected with clubroot, dormant spores may exist from the soil surface to a depth of 40 cm, especially in the soil layer above 30 cm, where the density is highest (Yan Honghai, 2009). Dormant spores can be spread over short distances in the field through rainwater, irrigation water, insects, soil nematodes, and agricultural activities. Dormant spores of clubroot can survive in water for 34 months. When the dormant spore concentration exceeds 10 spores / m⁻¹, prolonged irrigation with contaminated water can easily lead to clubroot. Dormant spores sink at a rate of 25 cm / day in still water, and spore sediments easily settle to the bottom of canals. Irrigation without pipes can also contribute to the spread and development of clubroot. Long-distance transmission is primarily through the transportation of infected plants or the transfer of contaminated soil.

[0003] Globally, there are 321 genera and 3,660 species of crucifers. Some of these plants are common crops with significant economic value. Clubroot has reportedly occurred in over 60 countries, causing yield losses of 10% to 15% in cruciferous crops. Furthermore, the disease can negatively impact the quality of agricultural products. For example, rapeseed seeds infected with clubroot can experience a 2% to 6% decrease in oil content, while the chlorophyll content in the oil increases by approximately 50%.

[0004] Currently, the common methods for preventing and controlling clubroot are breeding resistant varieties, using chemical agents, and utilizing agricultural measures and biological control. Of all these prevention and control methods, breeding resistant varieties is the safest and most effective. However, the development of resistant varieties is limited by the complex differentiation of pathogenic bacteria, the vulnerability of existing resistance genes (such as CRa and CRb) to strain mutation, and the difficulty of synergistically improving disease resistance and commercial traits (such as core compactness). This makes it difficult to cultivate long-term, effective, and disease-resistant varieties suitable for different regions.

[0005] Existing technologies generally have the following deficiencies (problems to be solved): the combination of single functional materials lacks a synergistic enhancement mechanism, the pH adjustment ability is insufficient (not reaching the optimal range of 7.2-7.5), and the dynamic balance between disease prevention and control and nutrient supply is not achieved. To this end, we proposed a composite matrix formula and its application for preventing and controlling clubroot in cruciferous crops. Summary of the Invention

[0006] The purpose of the present invention is to provide a composite matrix formula for preventing and treating clubroot of cruciferous crops and its application, which solves the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a composite matrix formula for preventing and treating clubroot of cruciferous crops, comprising the following raw materials in the following volume ratios: 10-30% peat, 50-70% calcined oyster shell powder, and 10-30% coconut shell biochar, wherein the calcined oyster shell powder is oyster shell crushed material treated at a high temperature of 800-1600°C, has a CaO content of ≥90%, a pH of 8-10, and a particle size of ≥30 mesh; the coconut shell biochar has a specific surface area of 600-1300 m 2 / g, particle size is 8-30 mesh.

[0008] Preferably, the pH value of the composite matrix is 7.2-7.8.

[0009] Preferably, the coconut shell biochar has an iodine adsorption value of 900-1250 mg / g, a methylene blue adsorption value of 135-210 mg / g, and a micropore ratio of ≥90% in the pore structure.

[0010] A method for preparing a composite matrix for preventing and treating clubroot of cruciferous crops comprises the following steps:

[0011] S1. After cleaning, calcine the oyster shells at 800-1600°C for 2-4 hours and crush them into ≥30 mesh;

[0012] S2. Carbonize the coconut shell at 500-700℃ under anoxic conditions for 3-5 hours to obtain a specific surface area of ≥600m 2 / g of biochar;

[0013] S3. Evenly mix the peat, calcined oyster shell powder and coconut shell biochar according to proportion.

[0014] Preferably, the application includes applying 100-200g of composite matrix per hole during transplanting, covering the root of the seedlings, and planting density is 70cm in row and 40cm in plant, and every 667m 2 2,380 plants were planted.

[0015] Preferably, the application increases the pH value of the rhizosphere soil to 7.5-7.9, and the exchangeable calcium ion content is ≥25 cmol / kg.

[0016] Preferably, application of the composite matrix reduces the cabbage clubroot disease index by 50-70% and increases the yield by 80-180%.

[0017] The present invention provides a composite matrix formula for preventing and treating clubroot disease in cruciferous crops. The composite matrix formula for preventing and treating clubroot disease in cruciferous crops has the following beneficial effects:

[0018] (1) Effectively regulating soil pH: The composite matrix of the present invention can significantly increase the pH value of the rhizosphere soil. For example, for the cabbage variety "Nongda Rouhong" (variety A), the pH value of the A2 treatment (using the composite matrix) was 7.84, which increased by 0.94 compared with the control CKA; for the "Hongshengbai" (variety B), the pH value of the B2 treatment was 7.9, which increased by 0.96 compared with the control CKB, making the soil pH closer to the appropriate range for clubroot inhibition and effectively inhibiting the growth of pathogens.

[0019] (2) Good disease control effect: It has a significant control effect on cabbage clubroot. In variety A, the incidence rate of treatment A2 is 63.6%, the disease index is 12.01, and the control effect is 58.84%; in variety B, the incidence rate of treatment B2 is 72.0%, the disease index is 10.51, and the control effect is 68.97%.

[0020] (3) Improve soil nutrient status: It can effectively increase the content of total nitrogen, available phosphorus, available potassium, organic matter, and exchangeable calcium ions in the soil, providing sufficient nutrients for crop growth. For example, the total nitrogen content of the A2 treatment of variety A was 1.72±0.05g / kg, available phosphorus was 195.30±37.3mg / kg, available potassium was 404.52±6.8mg / kg, organic matter was 63.82±2.14g / kg, and exchangeable calcium ions were 25.89±2.1cmol / kg, all significantly higher than the control CKA. The B2 treatment of variety B was also significantly better than the control CKB in terms of various nutrient indicators.

[0021] (4) Significantly increased crop yield: The plant height, plant weight, and yield of cabbage were significantly increased. Variety A2 treatment showed a plant height of 29.9±2.1 cm, a plant weight of 1.56±0.5 kg, and a yield of 3730.2 kg / mu; variety B2 treatment showed a plant height of 32.2±2.8 cm, a plant weight of 2.15±0.4 kg, and a yield of 5060.4 kg / mu, all significantly higher than their respective controls CKA and CKB.

[0022] (5) Synergistic effect: The combination of peat, calcined oyster shell powder and coconut shell biochar brings out the advantages of each component and forms a synergistic effect mechanism, which not only achieves disease prevention and control, but also ensures the nutritional supply of crops and achieves a dynamic balance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is an application flow chart of the present invention. DETAILED DESCRIPTION

[0024] 1. Test methods

[0025] 1.1 Experimental Reagents

[0026] Calcined oyster shell powder: produced by Taikang Pearl Products Factory, Tieshan Port District, Beihai City, particle size ≥30 mesh; CaO content ≥90%; pH 8.75, moisture ≤5.0%.

[0027] Coconut shell biochar: SC-104 coconut shell charcoal produced by Pingdingshan Tanernuo New Materials Co., Ltd., 6.72 yuan / kg, particle size 8-30 mesh, bulk density 500-550g / L, specific surface area 600-1300m 2 / g, ash content 5-10%, C content ≥93%.

[0028] Peat: Mixed by agricultural supply store.

[0029] 1.2 Test varieties: The test cabbage varieties were A: “Nongda Rouhong” and B: “Hongshengbai” from Jiaozhou Chinese Cabbage Research Institute.

[0030] 1.3 Experimental site: The experimental plots were selected from plots with a high incidence of clubroot and continuous cultivation of mustard tuber for more than 10 years. The planting density of cabbage was 70 cm in row and 40 cm in plant, with an average of 10000 square meters per 667 m. 2 2,380 plants were planted.

[0031] 1.4 Cultivation Conditions: The cabbage seedlings used in the experiment were grown in plug trays and transplanted on September 11, 2024. The bottom and edges of the pits were covered with 150 g of a substrate consisting of peat, oyster shell powder, and biochar in a mass ratio of 2:6:2. One seedling was planted in each hole, and the seeds were harvested on November 23. Uniform water and fertilizer management was implemented throughout the growth period.

[0032] 1.5 Cabbage clubroot survey: During the cabbage harvest period, a random sampling method was used to survey 30 plants at each location. The plants were graded according to the standards of NY / T1460.53-2014 "Guidelines for Field Efficacy Tests of Pesticides Part 52: Control of Clubroot of Cruciferous Vegetables with Fungicides". The number of diseased plants and the disease level in each plot were recorded. The incidence rate and disease index were calculated using formulas (1) and (2) respectively, and the control effect was calculated using formula (3). The disease grading standards are as follows:

[0033] Level 0: root growth, no tumor;

[0034] Grade 1: Only a small amount of tumor is present at the rootlet tip;

[0035] Grade 3: Small tumor on the lateral root;

[0036] Grade 5: The lateral root tumors are enlarged, and there are small tumors at the end of the main root, but the plant has no obvious deformity;

[0037] Level 7: The main root is completely swollen, the surface of the root is cracked, and the leaves of the plant wilt and turn yellow;

[0038] Level 9: The tumor-bearing part of the main root begins to crack and rot, and the plant wilts and dies;

[0039]

[0040]

[0041]

[0042] 1.6 Cabbage yield determination

[0043] Sample site selection: Random sampling ensures sample representativeness.

[0044] Measuring planting density: Use a tape measure to measure the distance between adjacent rows (an average of 3-5 rows) and the distance between plants (the average of 10 consecutive plants) to calculate the planting density.

[0045] Sample collection and weighing: 10-20 whole cabbages were dug up continuously at each sampling point, the soil at the roots and the outer yellow leaves were removed, the net weight of each plant was weighed, and the theoretical yield was calculated.

[0046] 2. Experimental Design

[0047] In this experiment, treatment groups A2 and B2 (peat: oyster shell powder: biochar = 2:6:2) were set up for two cabbage varieties, and control groups CKA and CKB (peat: oyster shell powder: biochar = 0:0:0) were set up. That is, the seeds were directly transplanted from the seedling pots into the field.

[0048] 2.1 Effects on rhizosphere soil pH

[0049] A2pH7.84, B2pH7.9. Compared with the respective variety controls, the pH value of A2 treatment increased by 0.94, and the pH value of B2 treatment increased by 0.96.

[0050] 2.2 The control effect of cabbage clubroot

[0051] The cultivation substrates were mixed in different proportions, and the incidence rate, disease index and control effect of cabbage clubroot were calculated by the formula. The results are shown in the table.

[0052]

[0053] * The same letters in each column indicate that the difference is not significant (P>0.05), and the different letters indicate that the difference is significant (P<0.05)

[0054]

[0055] 2.4 Effect of substrate ratio on cabbage yield

[0056] As shown in the table, the plant height and plant weight of the A2 treatment were significantly higher than those of the CKA treatment; the plant height and plant weight of the B2 treatment were significantly higher than those of the CKB treatment. The SPAD value of the A2 treatment for variety A was 34.3, higher than that of the CKA treatment, and the SPAD value of the B2 treatment for variety B was 38.6. Both treatments were significantly higher than the control group. Plant height directly affects the photosynthetic efficiency of cabbage. Appropriate plant height can ensure that the leaves receive sufficient sunlight, increase the photosynthetic rate, and thus increase dry matter accumulation. These differences may affect yield performance. For example, taller varieties generally have higher yield potential.

[0057] deal with Plant height / cm Single plant weight / kg SPAD A2 29.9±2.1ab 1.56±0.5ab 34.3±6.4ab CKA 28.4±3.0bc 0.86±0.1c 31.2±6.0b B2 32.2±2.8a 2.15±0.4a 38.6±4.4a CKB 22.9±2.5b 0.75±0.2b 27.1±3.9c

[0058] 2.3 Cabbage yield determination

[0059] Sample site selection: Random sampling ensures sample representativeness.

[0060] Measuring planting density

[0061] Row spacing and plant spacing: Use a tape measure to measure the distance between adjacent rows (average of 3-5 rows) and plant spacing (average of 10 consecutive plants)

[0062] Calculate density: Sample collection and weighing

[0063] Weight of single plant: 10-20 whole cabbages were dug up continuously at each sampling point, the soil at the roots and the outer yellow leaves were removed, and the net weight of each plant was measured.

[0064] Theoretical yield calculation:

[0065] The yield of A2 is 3730.2kg / mu, which is higher than that of CKA by 2063kg / mu.

[0066] The yield of B2, 5060.4 kg / mu, was higher than that of CKB, which was 1801 kg / mu.

[0067] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any person skilled in the art without departing from the concept and principle of the present invention should fall within the scope of protection of the present invention. It should also be noted that the various components of the present invention are not limited to the above-mentioned overall application. The various technical features described in the specification of the present invention can be selected one by one or multiple by multiple combinations according to actual needs. Therefore, the present invention should naturally cover other combinations and specific applications related to this case.

Claims

1. A composite matrix formula for preventing and treating clubroot of cruciferous crops, characterized in that: The invention is composed of the following raw materials in the following volume ratios: 10-30% peat, 50-70% calcined oyster shell powder, and 10-30% coconut shell biochar. The calcined oyster shell powder is oyster shell crushed material treated at a high temperature of 800-1600°C, with a CaO content of ≥90%, a pH value of 8-10, and a particle size of ≥30 mesh. The coconut shell biochar has a specific surface area of 600-1300m 2 / g, particle size is 8-30 mesh.

2. The composite matrix formula for preventing and treating clubroot of cruciferous crops according to claim 1, characterized in that: The pH value of the composite matrix is 7.2-7.

8.

3. The composite matrix formula for preventing and treating clubroot of cruciferous crops according to claim 1, characterized in that: The iodine adsorption value of the coconut shell biochar is 900-1250 mg / g, the methylene blue adsorption value is 135-210 mg / g, and the micropores in the pore structure account for ≥90%.

4. A method for preparing a composite matrix for preventing and treating clubroot of cruciferous crops, comprising preparing the composite matrix for preventing and treating clubroot of cruciferous crops according to any one of claims 1 to 3, wherein: The following steps are involved: S1. After cleaning, calcine the oyster shells at 800-1600°C for 2-4 hours and crush them into ≥30 mesh; S2. Carbonize the coconut shell at 500-700℃ under anoxic conditions for 3-5 hours to obtain a specific surface area of ≥600m 2 / g of biochar; S3. Evenly mix the peat, calcined oyster shell powder and coconut shell biochar according to proportion.

5. Use of the composite matrix according to any one of claims 1 to 3 in cabbage transplanting cultivation, characterized in that: The application includes applying 100-200g of composite matrix per hole during transplanting, covering the root of the seedlings, and planting density of 70cm in row and 40cm in plant. 2 2,380 plants were planted.

6. The use according to claim 5, characterized in that The application increases the pH value of the rhizosphere soil to 7.5-7.9, and the exchangeable calcium ion content is ≥25 cmol / kg.

7. The use according to claim 5, characterized in that Application of the composite matrix reduces the disease index of cabbage clubroot by 50-70% and increases the yield by 80-180%.

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