A coating agent for preventing and treating poplar canker and its application method

Abstract

This invention relates to a topical agent for preventing and treating poplar canker and its application method. The topical agent, by weight percentage, comprises the following ingredients: 0.1-0.2% pyraclostrobin; 1-3% wetting and dispersing agent; 0.2%-0.8% thickener; 2-4% antifreeze agent; 0.01%-0.3% micronutrient fertilizer; 0.1%-0.3% defoamer; and the balance being deionized water. Before application, first use a scraper to clean the ulcerated areas on the poplar branches and trunks, thoroughly scraping away the rotten tissue, extending 2-3 cm beyond the diseased area on both the upper and lower surfaces. Then, evenly and promptly apply the topical agent to the treated wound surface, cover it with breathable non-woven fabric, and then apply another layer of topical agent over the non-woven fabric, ensuring close adhesion to the branches and trunk. The topical agent of this invention is simple to use, highly effective, and can effectively control canker, reduce the impact on poplar growth, and achieve efficient prevention and treatment of poplar canker.

Description

Technical Field

[0001] This invention belongs to the field of pesticide technology, specifically relating to a topical agent for preventing and treating poplar rot and its application method. Background Technology

[0002] Poplar canker is primarily caused by *Valsa sordida* Nit. (Ascomycota) and *Cytospora* sp. (Deuteromycota), resulting in a tree disease that severely damages urban greening trees, poplar plantations, and shelterbelts. The disease mainly presents in two forms: trunk rot and branch dieback. Trunk rot primarily affects the bark of the main trunk, large branches, and forks, leading to bark ulceration and tissue necrosis. Numerous small protrusions (conidiophores of the pathogen) often appear at the lesions, and in humid conditions, large amounts of orange-yellow, filamentous material (conidial horns) are secreted. Branch dieback mainly occurs on twigs; after infection, the twigs quickly die without obvious canker symptoms. In years with disease outbreaks, it can cause severe tree decline, branch and trunk dieback, and even the death of the entire tree, resulting in significant economic and ecological losses to urban greening, poplar plantations, and shelterbelts.

[0003] Currently, the control of poplar canker disease still mainly relies on chemical application, with the common procedure being to scrape off the lesions and then apply the medication to the wound. Existing topical medications can be mainly divided into two categories: The first is traditional agents, represented by lime sulfur and some sulfur-containing preparations (such as arsenic trioxide / traditional sulfur preparations), which, while able to inhibit pathogen spread to some extent, often suffer from short-lasting effects, poor resistance to rain washout, strong irritation to the bark, and potential environmental risks. The second category includes fungicides such as tebuconazole and pyraclostrobin. Although these have good inhibitory activity against pathogens, their conventional formulations, such as wettable powders and suspensions, are difficult to fully adhere to the bark wound and form a continuous, dense protective film, leading to easy loss of active ingredients and difficulty in building a long-term stable protective layer on the bark surface, thus affecting actual efficacy and control stability.

[0004] Furthermore, existing chemical agents primarily focus on killing pathogens, lacking the ability to promote healing of bark tissue damage caused by diseases. This makes it difficult for trees to repair themselves, leading to frequent disease recurrence. Therefore, developing a specialized, long-lasting protective coating that combines highly effective bactericidal action with wound-healing properties is of great significance for controlling poplar canker and promoting healthy forest growth.

[0005] In view of this, the present invention provides a novel topical agent for the prevention and control of poplar canker and its corresponding treatment method. This solution, by optimizing the formulation components and application method, aims to solve the problems of single function and short duration of effect in existing technologies, thereby achieving efficient and long-lasting control of poplar canker and promoting tree recovery. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a coating agent for preventing and treating poplar rot disease and its preparation method, which has the characteristics of simple processing and good prevention and treatment effect.

[0007] This invention provides a topical agent for preventing and treating poplar rot disease, comprising the following raw materials by weight percentage:

[0008] Pyraclostrobin 0.1-0.2%;

[0009] Wetting and dispersing agent 1-3%;

[0010] Thickener 0.2%-0.8%;

[0011] Antifreeze 2-4%;

[0012] Micronutrient fertilizer: 0.01%-0.3%;

[0013] Defoamer 0.1%-0.3%;

[0014] The remainder is deionized water.

[0015] The raw materials were wet-milled to obtain pyraclostrobin coating.

[0016] In this invention, the wetting and dispersing agent is sodium lignosulfonate, naphthalene sulfonate formaldehyde condensate (NNO), sodium dodecyl sulfate, phenylethylphenol polyoxyethylene ether phosphate, etc.

[0017] The thickener described in this invention is any one of xanthan gum, gum arabic, gelatin, and polyvinyl alcohol.

[0018] The antifreeze agent described in this invention is any one of ethylene glycol, propylene glycol, and glycerol.

[0019] The defoamer described in this invention is any one of polydimethylsiloxane, fluorosiloxane, and ethylene glycol siloxane.

[0020] The micronutrient fertilizer described in this invention is any one of zinc, copper, manganese, and copper soluble sulfate compound.

[0021] The pyraclostrobin coating obtained by this invention can be used to prevent and control poplar canker.

[0022] This invention also specifically discloses a method for preparing a pyraclostrobin coating for preventing and controlling poplar canker, comprising the following steps:

[0023] (1) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0024] (2) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0025] (3) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0026] (4) Add the aqueous solution of trace element fertilizer to the paste obtained in step (3) and continue stirring until it is evenly mixed;

[0027] (5) Let the paste obtained in step (4) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0028] This invention also provides a method for using the aforementioned coating, namely a method for treating wounds infected with poplar canker, wherein the treatment is performed as follows:

[0029] (1) Clean the rotten parts of poplar branches with a sterilized scraper, and thoroughly scrape away the rotten tissue; gently scrape away the diseased outer bark, leaving the healthy bark layer;

[0030] (2) Apply the smear evenly to the ulcer, and use a breathable non-woven fabric to cover the wound. Apply a layer of smear on the outside of the non-woven fabric to make the non-woven fabric adhere tightly to the poplar branches.

[0031] Compared with existing technologies, this invention has the following advantages: the topical agent prepared by the above method has significant preventive and curative effects. Pyraclostrobin can effectively inhibit pathogenic fungi; xanthan gum has a thickening effect, which can enhance the adhesion and slow-release function of the agent on the bark surface; the added trace elements can promote the formation of callus tissue on branches and trunks and accelerate wound healing. Based on the treatment method of scraping off the affected area first, then applying the agent and covering it with non-woven fabric, the agent can act on the lesion for a long time, effectively preventing reinfection and achieving highly efficient and long-lasting control of this disease. Detailed Implementation

[0032] Example 1

[0033] A pyraclostrobin coating agent, the specific preparation steps of which are as follows:

[0034] (1) Prepare 200g of sample, by mass percentage: 0.2% pyraclostrobin, 2% wetting and dispersing agent naphthalene sulfonate formaldehyde condensate (NNO), 0.4% xanthan gum, 2% ethylene glycol, 0.1% polydimethylsiloxane, 0.01% zinc sulfate, and deionized water to make up to 100%;

[0035] (2) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0036] (3) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0037] (4) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0038] (5) Add the aqueous solution of trace element fertilizer to the paste obtained in step (4) and continue stirring until it is evenly mixed;

[0039] (6) Let the paste obtained in step (5) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0040] Example 2

[0041] A pyraclostrobin coating agent, the specific preparation steps of which are as follows:

[0042] (1) Prepare 200g of sample, by mass percentage: 0.15% pyraclostrobin, 3% sodium dodecyl sulfate (wetting and dispersing agent), 0.2% xanthan gum, 3% propylene glycol, 0.2% ethylene glycol siloxane, 0.1% ferric sulfate, and deionized water to make up to 100%;

[0043] (2) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0044] (3) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0045] (4) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0046] (5) Add the aqueous solution of trace element fertilizer to the paste obtained in step (4) and continue stirring until it is evenly mixed;

[0047] (6) Let the paste obtained in step (5) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0048] Example 3

[0049] A pyraclostrobin coating agent, the specific preparation steps of which are as follows:

[0050] (1) Prepare 200g of sample, by mass percentage: 0.1% pyraclostrobin, 1% sodium lignosulfonate (wetting and dispersing agent), 0.3% gum arabic, 3% ethylene glycol, 0.1% fluorosiloxane, 0.2% manganese sulfate, and deionized water to make up to 100%;

[0051] (2) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0052] (3) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0053] (4) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0054] (5) Add the aqueous solution of trace element fertilizer to the paste obtained in step (4) and continue stirring until it is evenly mixed;

[0055] (6) Let the paste obtained in step (5) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0056] Example 4

[0057] A pyraclostrobin coating agent, the specific preparation steps of which are as follows:

[0058] (1) Prepare 200g of sample, by mass percentage: 0.2% pyraclostrobin, 2.5% wetting and dispersing agent phenylethyl phenol polyoxyethylene ether phosphate salt, 0.6% gelatin, 4% glycerol, 0.1% polydimethylsiloxane, 0.3% ferric sulfate, and deionized water to make up to 100%;

[0059] (2) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0060] (3) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0061] (4) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0062] (5) Add the aqueous solution of trace element fertilizer to the paste obtained in step (4) and continue stirring until it is evenly mixed;

[0063] (6) Let the paste obtained in step (5) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0064] Example 5

[0065] A pyraclostrobin coating agent, the specific preparation steps of which are as follows:

[0066] (1) Prepare 200g of sample, by mass percentage: 0.1% pyraclostrobin, 2% lignin sulfonate wetting and dispersing agent, 0.8% polyvinyl alcohol, 4% glycerol, 0.3% fluorosiloxane, 0.05% magnesium sulfate, and deionized water to make up to 100%;

[0067] (2) Add pyraclostrobin technical and half the amount of wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A;

[0068] (3) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B;

[0069] (4) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste.

[0070] (5) Add the aqueous solution of trace element fertilizer to the paste obtained in step (4) and continue stirring until it is evenly mixed;

[0071] (6) Let the paste obtained in step (5) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the pyraclostrobin coating agent.

[0072] Example 6: Prevention and Control Efficacy Test

[0073] To evaluate the efficacy of the pyraclostrobin topical application of this invention against poplar canker, poplar trees with uniform vigor and severe disease incidence were selected for the experiment. A randomized block design was used with three treatments: Treatment 1 received the pyraclostrobin topical application of this invention; Treatment 2 received 0.15% pyraclostrobin ointment; and Treatment 3 served as a blank control (no treatment). Each treatment had three replicates, with four trees per replicate, and a 3-meter isolation zone between replicates. Before application, canker lesions were uniformly scraped down to the healthy bark, and the lesion area was recorded. Two applications of the agent were applied, 10 days apart. Ninety days after treatment, the lesion area was reassessed, and the lesion expansion rate and inhibition rate were calculated using the following formulas:

[0074] Expansion rate = (Lesion area after application - Lesion area before application) × 100 / Lesion area before application

[0075] Inhibition rate = (Control lesion expansion rate - Treatment lesion expansion rate) × 100 / Control lesion expansion rate.

[0076] The experimental results are expressed as the average of each treatment and each replicate. One-way ANOVA was performed to compare the lesion expansion rates between different treatments. When the differences between treatments reached a significant level, Duncan's new multiple range test was used to perform multiple comparisons at the P < 0.05 level. Different lowercase letters indicate significant differences between treatments.

[0077] The efficacy of the topical agents prepared in the above five embodiments was tested, and the results are shown in Table 1:

[0078] Table 1. Test results of the efficacy of the topical coating in controlling poplar canker.

[0079] deal with Inhibition rate (%) control drug 73.8±2.2d Example 1 88.6±0.6a Example 2 86.1±1.7bc Example 3 84.8±2.5c Example 4 87.7±1.9ab Example 5 85.0±1.3c

[0080] The topical agent prepared by the above method has significant preventive and therapeutic effects. During treatment, first, use a scraper to clean the rotten area of ​​the poplar branch, thoroughly removing the decayed tissue; gently scrape away the diseased outer bark, being careful to extend it 2-3 cm beyond the diseased area, leaving the healthy bark intact; then, apply the topical agent evenly to the rotten area, and place a breathable non-woven fabric over the wound, applying another layer of topical agent over the non-woven fabric, ensuring the non-woven fabric adheres tightly to the poplar branch. This treatment method is simple, quick, and effective, reducing the impact of the disease on poplar growth and achieving long-term prevention and control of poplar canker.

Claims

1. A topical agent for preventing poplar canker, characterized in that, By weight percentage, it contains the following ingredients: Pyraclostrobin 0.1-0.2%; Wetting and dispersing agent 1-3%; Thickener 0.2%-0.8%; Antifreeze 2-4%; Micronutrient fertilizer: 0.01%-0.3%; Defoamer 0.1%-0.3%; The remainder is deionized water.

2. The topical agent for preventing poplar rot according to claim 1, characterized in that, The wetting and dispersing agents are sodium lignosulfonate, naphthalene sulfonate formaldehyde condensate (NNO), sodium dodecyl sulfate, and phenylethyl phenol polyoxyethylene ether phosphate.

3. The topical agent for preventing poplar rot according to claim 1, characterized in that, The thickener is any one of xanthan gum, gum arabic, gelatin, and polyvinyl alcohol.

4. The topical agent for preventing poplar rot according to claim 1, characterized in that, The antifreeze is any one of ethylene glycol, propylene glycol, and glycerol.

5. The topical agent for preventing poplar rot according to claim 1, characterized in that, The defoamer is any one of polydimethylsiloxane, fluorosiloxane, and ethylene glycol siloxane.

6. The topical agent for preventing poplar rot according to claim 1, characterized in that, The micronutrient fertilizer is any one of zinc, copper, manganese, or copper soluble sulfate compound.

7. A method for preparing the coating for preventing poplar canker as described in claim 1, characterized in that, Includes the following steps: (1) Add pyraclostrobin technical and half of the wetting and dispersing agent to a portion of deionized water, and pre-disperse by high-speed shearing to obtain suspension A; (2) Slowly add the thickener and antifreeze to the remaining deionized water, stir thoroughly to swell, and form a uniform gel to obtain solution B; (3) Mix suspension A with solution B, add the remaining wetting and dispersing agent and defoamer, and perform wet grinding using a vertical sand mill to control the particle size to below 5 µm to obtain a uniform paste. (4) Add the aqueous solution of trace element fertilizer to the paste obtained in step (3) and continue stirring until it is evenly mixed; (5) Let the paste obtained in step (4) stand to defoam, and filter the zirconium oxide beads with gauze to obtain the coating agent.

8. The method of using the coating agent for preventing poplar canker as described in claim 1, characterized in that: Process it as follows: (1) Clean the rotten parts of poplar branches with a sterilized scraper, and thoroughly scrape away the rotten tissue; gently scrape away the diseased outer bark, leaving the healthy bark layer; (2) Apply the smear evenly to the ulcer, and use a breathable non-woven fabric to cover the wound. Apply a layer of smear on the outside of the non-woven fabric to make the non-woven fabric adhere tightly to the poplar branches.