Field pesticide effect evaluation method of pesticide for preventing and treating potato bacterial wilt

Abstract

The invention provides a field pesticide effect evaluation method of a pesticide for preventing and treating potato bacterial wilt. The method comprises the following steps: breeding buds on a seedbed; districts are divided, test districts are arranged in random district groups, four times of repetition are set, the number of the districts is determined according to the test processing number, and meanwhile a blank control area is set; setting a protection row; fixing buds of the seed potatoes; fixed-point transplanting; scientific prevention and control of potato late blight are uniformly carried out according to a field management method; calculating disease index and plant control effect according to investigation results, calculating potato disease rate and potato block control effect, and evaluating the field pesticide effect of the potato bacterial wilt prevention and control agent according to the data. According to the method, the investigation difficulty in the pesticide effect identification process is simplified, the pesticide effect identification accuracy is improved, the direct economic loss caused by the disease is reduced, and the method has important significance on healthy growth of field potatoes.

Description

Technical Field

[0001] The invention relates to the technical field of potato bacterial wilt prevention and control, and in particular to a field efficacy evaluation method of a drug for preventing and controlling potato bacterial wilt. Background Art

[0002] Potato bacterial wilt, also known as potato blight, is a typical vascular disease caused by Ralstonia solanacearum, which can occur throughout the potato growth period. Ralstonia solanacearum proliferates and spreads in the xylem vessels, blocking the internal water and nutrient transport of potatoes, causing tuber rot and acute dehydration of plants, wilt and death. In my country's main potato producing areas, potato yields decreased by 10% to 15% or even 80% to 100% due to infection with bacterial wilt in epidemic years. Due to the wide distribution of the disease, a wide host range, and strong survival and transmission capabilities, the prevention and control of bacterial wilt has always been a global problem. At present, there is no agent that can achieve a good prevention and control effect on potato bacterial wilt, and the development of new agents is imminent. Conducting field efficacy evaluation tests is the most intuitive and accurate way to verify whether new agents are effective.

[0003] The efficacy evaluation method will directly affect the evaluation results of the efficacy of the pesticide. Therefore, it is very important to adopt a scientific and reliable efficacy evaluation method. At present, no systematic description of the field test method for the efficacy evaluation of potato bacterial wilt has been retrieved. The field efficacy test adopts the same test method as the efficacy test of other diseases. However, the characteristics of bacterial wilt are very different from other diseases. Using traditional test methods, it is impossible to accurately and quickly identify the efficacy. Summary of the invention

[0004] Technical problem to be solved: In view of the shortcomings of the prior art, the present invention provides a field efficacy evaluation method for a drug for preventing and controlling potato bacterial wilt. The method simplifies the difficulty of investigation during efficacy identification, improves the accuracy of efficacy identification, reduces the direct economic losses caused by the disease, and is of great significance to the healthy growth of potatoes in the field.

[0005] Technical solution: A field efficacy evaluation method for a drug for controlling potato bacterial wilt, the steps of the method are as follows:

[0006] Step 1: germination in the seedbed:

[0007] Plant 50-60g uniform-sized virus-free seed potatoes in the seedbed;

[0008] Step 2: Field Transplanting:

[0009] 1) Divide the plots. The experimental plots are arranged in a randomized complete block design with 4 replications. Determine the number of plots according to the number of experimental treatments. At the same time, set up a blank control plot. The area of each plot is not less than 20 m 2 , and a total of 120 potato plants are planted in each plot.

[0010] 2) Set up border rows. Plant 2 - 4 rows of border rows around the entire experimental area. Select a variety susceptible to bacterial wilt or a variety with poorer resistance than the experimental variety for the border rows.

[0011] 3) Determine the buds of the seed potatoes. When the buds of the seed potatoes planted on the seedbed in step 1 grow to a height of 3 - 5 cm, remove the film and transplant. Take out the seed potatoes and determine the buds. Only retain 4 strong buds of uniform size on each seed potato.

[0012] 4) Transplant at fixed points. According to the conventional planting pattern, transplant the seed potatoes with determined buds into the holes made in the corresponding experimental plots, with the buds facing up, and then cover the holes with fine soil.

[0013] 5) Field management. Carry out artificial root irrigation treatment or chemical spraying treatment according to the treatment plan of the tested chemicals for controlling potato bacterial wilt. When the seedlings are 15 - 20 cm tall, carry out intertillage and weed control, and topdress with nitrogen fertilizer. At the same time, according to the occurrence time and incidence pattern of potato late blight in this region, carry out scientific prevention and control of potato late blight uniformly according to the field management method.

[0014] Step 3, Experimental investigation and result analysis:

[0015] 1) Method for investigating potato plants in the field for bacterial wilt. The severity (R) of potato bacterial wilt is divided into 5 grades. Grade 0 means healthy and asymptomatic. Grade 1 means that the leaves wither with 0 < R ≤ 1 / 4. Grade 2 means that the leaves wither with 1 / 4 < R ≤ 1 / 2. Grade 3 means that the leaves wither with 1 / 2 < R ≤ 3 / 4. Grade 4 means that the leaves wither with 3 / 4 < R ≤ 1. Investigate all the plants in each plot. The investigation time starts from the initial stage of disease occurrence in the blank control plot, at intervals of 7 - 15 days. The investigation ends when the disease index in the control plot reaches 90 - 100. Calculate the disease index and the control effect of the plants. The formulas are as follows:

[0016] Disease index = ∑[Number of diseased plants at each grade × Representative value at each grade] / [Total number of investigated plants × 4] × 100,

[0017] Control effect of plants (%) = (Disease index of the control - Disease index of the treatment) / Disease index of the control × 100,

[0018] 2) Method for measuring potato yields in the field for bacterial wilt. After the plants in the field are mature, harvest all the experimental plots, distinguish the healthy potato tubers from the potato tubers infected with bacterial wilt, weigh them separately, and calculate the disease tuber rate and the control effect of the potato tubers. The formulas are as follows:

[0019] Diseased potato rate (%) = diseased potato weight / total weight of investigated tubers × 100,

[0020] Tuber control effect (%) = (disease rate of tubers in the control area - disease rate of tubers in the treatment area) / disease rate of tubers in the control area × 100,

[0021] 3) Result analysis: Based on the calculation results of the disease index and plant control effect in step 1) and the calculation results of the diseased potato rate and tuber control effect in step 2), the field efficacy of the tested agent for controlling potato bacterial wilt is evaluated.

[0022] The specific steps of step one described above are:

[0023] 1) Selection of test sites: select test sites with good geographical isolation, convenient transportation, and fertile soil where potato bacterial wilt is likely to occur.

[0024] 2) Seed potato selection: select virus-free seed potatoes of uniform size of 50-60g.

[0025] 3) Seedbed preparation: Choose a sunny slope plot with flat terrain, healthy and fertile soil, close to the experimental field and easy to manage as the bud raising bed. Level the seedbed, with the bed surface 3-5cm above the ground and 1.2m wide.

[0026] 4) Place the seed potatoes, remove the rotten, mixed, diseased, inferior and cracked ones, wipe off the sprouted buds on the tubers, place the seed potatoes with the buds facing upwards, and place them neatly one by one, so that the seed potatoes form a flat surface at the top, with 1cm between each tuber, 0.8m wide, and 0.2m away from the edge of the arch shed.

[0027] 5) Cover with soil and film. After placing the seed potatoes, use a sieve to sift high-quality fertile fine soil, cover it evenly on the surface of the seed potatoes while sieving, with a soil thickness of 3cm. Use a 2.1-2.3m bamboo arch shed, cover it with white plastic film, seal the edges around, clean the drainage ditch, and keep the soil moisture in the shed at 70%-75%.

[0028] In the above-mentioned step 2) the test variety is the susceptible variety Mira, and the protected row variety is the susceptible E-potato No. 9.

[0029] In the technical solution of the present invention, the accuracy of drug efficacy evaluation is improved by the following measures, specifically:

[0030] (1) Guarantee the germination rate. Direct seeding of sterile buds will cause problems such as lack of seedlings and uneven germination. Through fixed bud transplanting, diseased potatoes, rotten potatoes, mixed potatoes, and ungerminated or thinly germinated potatoes are eliminated, which can ensure that the test germination rate is 100%. At the same time, the germination of seedlings is uniform and strong, ensuring that the test treatments are at the same level. Fixed-point drilling and transplanting can ensure that the seed potatoes are arranged neatly, which is convenient for later root irrigation treatment.

[0031] (2) Improve the accuracy of the results. Direct seeding will cause each seed potato to have an uneven number of tillers on the main stem, which makes it difficult to count the disease level of bacterial wilt, increases the statistical workload, and also has a certain impact on the results due to differences between individuals. Through fixed bud transplanting, it is ensured that 4 strong buds are left on each seed potato, ensuring that the entire test is tested at the same level; manual judgment of the disease level will increase the error due to differences between individual plants; by retaining 4 strong buds and comparing with the disease grading standard, the disease level of the plant can be quickly determined, reducing the difficulty of the investigation.

[0032] (3) Increase operating space. When potato plants are infected with bacterial wilt, the entire tillering stem will wilt. By raising seedlings and determining the number of tillering stems of each plant, the disease level can be quickly counted. By removing excess buds and reducing the number of stems, ventilation can be increased and the incidence of late blight in the field can be reduced. At the same time, the operating space can be increased to facilitate later root irrigation operations and survey statistics.

[0033] (4) Seed potato selection: Use virus-free seed potatoes to reduce plant wilting caused by other diseases, which in turn affects statistical data.

[0034] (5) Fairness of the experiment. Grow buds in healthy soil to avoid disease infection during the budding period and ensure that they are at the same level before transplanting to avoid affecting the experiment. Conduct the experiment in a diseased field to ensure that the disease is uniform in the field.

[0035] (6) Setting of early warning varieties. Setting of early warning varieties can predict the time of field disease in advance and provide a reference for the start time of later experimental pesticide treatment.

[0036] Beneficial effects: The field efficacy evaluation method of a drug for preventing and controlling potato bacterial wilt provided by the present invention has the following beneficial effects:

[0037] 1. The efficacy evaluation method of the present invention makes some changes on the basis of the conventional planting method, which reduces the difficulty of investigation during the efficacy identification process and improves the accuracy of efficacy identification.

[0038] 2. The efficacy evaluation method of the present invention plays a key role in the research and development of new agents for preventing and controlling potato bacterial wilt. There is a big difference between indoor identification and field identification. Conducting field efficacy identification can accurately reflect the control effect of the agent.

[0039] 3. Through the efficacy evaluation method of the present invention, it is possible to discover and screen out agents that are effective in preventing and controlling bacterial wilt, effectively prevent and control potato bacterial wilt in the field, reduce the direct economic losses caused by the disease, and have important significance for the healthy growth of potatoes in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1This is a block arrangement diagram for the 4-repetition test plot. DETAILED DESCRIPTION

[0041] The specific steps of the field efficacy evaluation method for potato bacterial wilt of the implementation method are as follows:

[0042] Step 1: germination in the seedbed:

[0043] 1) Selection of test sites: select test sites with good geographical isolation, convenient transportation, and fertile soil where potato bacterial wilt is likely to occur.

[0044] 2) Seed potato selection: select virus-free seed potatoes of uniform size of 50-60g.

[0045] 3) Seedbed preparation: Choose a sunny slope plot with flat terrain, healthy and fertile soil, close to the experimental field and easy to manage as the bud-raising bed. Level the seedbed, with the bed surface 3-5cm above the ground and 1.2m wide. Do not apply chemical fertilizers.

[0046] 4) Place the seed potatoes, remove the rotten, mixed, diseased, inferior and cracked ones, wipe off the sprouted buds on the tubers, place the top of the seed potatoes with buds facing upwards, and place them neatly one by one so that the seed potatoes form a flat surface at the top. There is a 1cm interval between each tuber, the sowing surface is 0.8m wide, and the distance from the edge of the arch shed is 0.2m to avoid marginal effects and ensure that the water and heat of the seed potatoes on the germination bed are uniform.

[0047] 5) Cover with soil and film. After placing the seed potatoes, sieve high-quality fertile fine soil with a sieve, cover the surface of the seed potatoes evenly while sieving, with a soil thickness of 3cm. Use a 2.1-2.3m bamboo arch shed, cover with white plastic film, seal the edges around, and clean the drainage ditch (keep the soil moisture in the shed at 70-75%).

[0048] Step 2: Field Transplanting:

[0049] 1) Divide the plots, arrange the experimental plots in random blocks, set 4 replicates, determine the number of plots according to the number of experimental treatments, and set a blank control area. Each plot has an area of ​​20m 2 (can be greater than or equal to 20m 2 ), 3.6m wide, 5.56m long, 27.8cm plant spacing, 60cm row spacing, 6 rows, 20 plants per row, 120 plants per plot, a circle of protection rows planted around each plot to reduce the marginal effect of the test area and reduce the test error. Walkways with a width of 70cm were set between strips and plots. Figure 1 As shown, I, II, III, and IV represent four repetitions, respectively.

[0050] 2) Set up protective rows. Plant 2 - 4 rows of protective rows around the entire experimental area. For the protective row varieties, choose varieties susceptible to bacterial wilt or varieties with lower resistance than the experimental varieties (for the experimental area, the susceptible variety Mira can be selected, and for the protective row, the susceptible variety E-potato 9 can be selected as the early warning variety). The early warning variety can be used for early disease warning, predicting in advance the disease onset time of the experimental plots, thereby clarifying the time node for conducting chemical treatments on the experimental plots and ensuring that each experimental plot is at the same disease level during treatment.

[0051] 3) Determine the buds of the seed potatoes. When the bud length of the seed potatoes planted on the seedbed in step one reaches 3 - 5 cm, uncover the film and transplant. Take out the seed potatoes and determine the buds. Only retain 4 strong buds of uniform size on each seed potato, and wipe off the rest of the buds.

[0052] 4) Fixed-point transplanting. According to the conventional planting mode, first form ridges with a ridge width of 30 cm and a ridge height of 15 - 20 cm, then make fixed-point holes with a hole spacing of 27.8 cm. Then transplant the seed potatoes with determined buds into the holes made in the corresponding experimental plots, with the buds facing upwards, and then cover the holes with fine soil.

[0053] 5) Field management. Conduct artificial root irrigation or chemical spraying treatments according to the treatment plan of the tested chemicals for controlling potato bacterial wilt. When the seedling height is 15 - 20 cm, carry out intertillage and weed control, and top-dress with nitrogen fertilizer. At the same time, according to the occurrence time and incidence pattern of potato late blight in this region, carry out scientific prevention and control of potato late blight in accordance with the field management method to avoid plant death caused by late blight, which may affect the test results and introduce errors.

[0054] Step three, experimental investigation and result analysis:

[0055] 1) Field plant investigation method for potato bacterial wilt. The severity (R) of potato bacterial wilt is divided into 5 grades. Grade 0 is healthy and asymptomatic, grade 1 is with leaf wilting where 0 < R ≤ 1 / 4, grade 2 is with leaf wilting where 1 / 4 < R ≤ 1 / 2, grade 3 is with leaf wilting where 1 / 2 < R ≤ 3 / 4, and grade 4 is with leaf wilting where 3 / 4 < R ≤ 1. Investigate all the plants in each plot. The investigation time starts from the initial stage of disease occurrence in the blank control plot, at intervals of 7 - 15 days, and the investigation ends when the disease index in the control plot reaches 90 - 100. Calculate the disease index and plant control effect. The formulas are as follows:

[0056] Disease index = ∑[number of diseased plants at each level × representative value at each level] / [total number of investigated plants × 4] × 100,

[0057] Plant control effect (%) = (control disease index - treatment disease index) / control disease index × 100,

[0058] 2) The method of measuring potato tuber yield in the field for potato bacterial wilt is to harvest all the test plots after the field plants mature, and distinguish healthy tubers from tubers with bacterial wilt, weigh them separately, and calculate the diseased tuber rate and tuber control effect. The formula is:

[0059] Diseased potato rate (%) = diseased potato weight / total weight of investigated tubers × 100,

[0060] Tuber control effect (%) = (disease rate of tubers in the control area - disease rate of tubers in the treatment area) / disease rate of tubers in the control area × 100,

[0061] 3) Result analysis: Based on the calculation results of the disease index and plant control effect in step 1) and the calculation results of the diseased potato rate and tuber control effect in step 2), the field efficacy of the tested agent for controlling potato bacterial wilt is evaluated.

[0062] Example 1

[0063] 1. Test purpose:

[0064] This embodiment carried out a field efficacy test on two drug treatments according to the above method, and set a blank control CK to analyze the efficacy of the two drug treatments. The drug treatment requires seed potatoes and soil treatment during transplanting and sowing, and root irrigation is performed at the seedling stage (when the susceptible varieties in the protection row begin to develop the disease), bud stage, flowering stage, and tuber expansion mid-term, with 300 mL per plant. The blank control was investigated from the early stage of the disease, and the investigation was conducted every 10 days, for a total of 4 times.

[0065] 2. Test methods:

[0066] 2.1. Prepare medicine 1 and medicine 2

[0067] Agent 1 is composed of Pseudomonas fluorescens and thiophanate-methyl, and agent 2 is composed of Bacillus amyloliquefaciens HT2003 and sinoprotinin.

[0068] The fluorescein Pseudomonas was purchased from Shandong Huimin Zhonglian Biotechnology Co., Ltd., with a dosage of 600 g / mu; thiophanate-methyl was purchased from Zhejiang Longwan Chemical Co., Ltd., with a dosage of 120 mL / mu; Bacillus amyloliquefaciens HT2003 was purchased from Shaanxi Hengtian Bio-Agriculture Co., Ltd., with a dosage of 100 g / mu; and sinomenine was purchased from Fujian Kaili Biological Products Co., Ltd., with a dosage of 3000 g / mu.

[0069] Select 50-60g virus-free seed potatoes for germination in a healthy nursery, place the selected seed potatoes evenly on the seedbed, cover with soil and film after placement; when the height of the seed potato buds on the seedbed is about 3-5cm, remove the film, and fix the seed potatoes. Keep 4 strong buds and transplant them to the potato bacterial wilt disease nursery. The diseased nursery field should be divided into test plots in advance. First, divide the seed potatoes with fixed buds into 3 parts, 480 in each, named treatment 1, treatment 2, and CK respectively; the remaining seed potatoes do not need to be fixed, and are directly transplanted to the protection row. Spray the prepared agent 1 evenly on the seed potatoes and test plots of treatment 1, and spray the prepared agent 2 evenly on the seed potatoes and test plots of treatment 2. Spray the CK group with the same volume of clean water. Transplant the treated seed potatoes to the corresponding test plots that have been divided in the potato bacterial wilt disease nursery test site. According to the requirements of the agent treatment, root irrigation is carried out at the seedling stage, budding stage, flowering stage, and mid-stage of tuber expansion.

[0070] Test results:

[0071] The disease index and control effect of the plants in the field are shown in Table 1 below.

[0072] Table 1

[0073]

[0074] As shown in Table 1, from June 10 to July 9, the average disease index of field plants in treatment 1 was 2.60-59.54, the average disease index of treatment 2 was 2.24%-59.43%, and the average disease index of control CK was 7.03-98.28; the control effect of field plants in treatment 1 was 39.32%-75.67%, and the control effect of field plants in treatment 2 (%) was 39.53%-77.50%. The control effect of field plants in both treatments reached the highest on June 20.

[0075] The situation of diseased potatoes in the field is shown in Table 2.

[0076] Table 2

[0077]

[0078] As shown in Table 2, the diseased potato rates (%) of treatment 1 and treatment 2 were 45.26% and 42.83%, respectively, both lower than the diseased potato rate of the control CK (70.11%); the tuber control effect (%) of treatment 1 and treatment 2 was 35.45% and 38.91%, respectively.

[0079] In summary, both treatments 1 and 2 have certain control effects on potato bacterial wilt in the field, especially in the early and middle stages of potato growth, and the control effect of treatment 2 is slightly better than that of treatment 1. Treatments 1 and 2 have certain control effects on potato tuber bacterial wilt infection, among which the control effect of treatment 2 on potato tubers is slightly higher than that of treatment 1.

[0080] The embodiments of the present invention are described in detail above. For those skilled in the art, according to the ideas of the embodiments of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for evaluating the efficacy of a drug for preventing and controlling potato bacterial wilt, characterized in that The steps of this method are as follows: Step 1: Seedling bed germination: Plant 50 - 60 g of virus-free seed potatoes of uniform size on the seedling bed; Step 2: Field transplantation: 1) Divide the plots into small areas, arrange the experimental plots in random blocks, set up 4 replicates, determine the number of plots according to the number of experimental treatments, and set up a blank control area. The area of ​​each plot should not be less than 20m 2 , a total of 120 potato plants were planted in each plot. 2) Set up protective rows. Plant 2 - 4 rows of protective rows around the entire test area. For the protective row variety, select a variety susceptible to bacterial wilt or a variety with worse resistance than the test variety. 3) Determine the buds of the seed potatoes. When the bud length of the seed potatoes planted on the seedling bed in Step 1 reaches 3 - 5 cm, uncover the film and transplant. Take out the seed potatoes to determine the buds, and only keep 4 strong buds of uniform size on each seed potato. 4) Fixed-point transplantation. According to the conventional planting pattern, transplant the seed potatoes with determined buds into the holes dug in the corresponding test plots, with the buds facing upwards, and then cover the holes with fine soil. 5) Field management. Carry out artificial root irrigation treatment or chemical spraying treatment according to the test chemical treatment plan for controlling potato bacterial wilt. When the seedling height is 15 - 20 cm, carry out intertillage and weeding and topdress with nitrogen fertilizer. At the same time, according to the occurrence time and incidence pattern of potato late blight in this region, carry out scientific prevention and control of potato late blight uniformly according to the field management method. Step 3: Experimental investigation and result analysis: 1) Method for investigating potato plants in the field for bacterial wilt. The severity of potato bacterial wilt (R) is divided into 5 grades. Grade 0 means healthy and asymptomatic. Grade 1 means leaf wilting with 0 < R ≤ 1 / 4. Grade 2 means leaf wilting with 1 / 4 < R ≤ 1 / 2. Grade 3 means leaf wilting with 1 / 2 < R ≤ 3 / 4. Grade 4 means leaf wilting with 3 / 4 < R ≤ 1. Investigate all plants in each plot. The investigation time starts from the initial stage of disease occurrence in the blank control plot, with an interval of 7 - 15 days. The investigation end time is when the disease index in the control plot reaches 90 - 100. Calculate the disease index and plant control effect. The formulas are as follows: Disease index = ∑[Number of diseased plants at each level × Representative value at each level] / [Total number of investigated plants × 4] × 100 Plant control effect (%) = (Control disease index - Treatment disease index) / Control disease index × 100 2) Method for measuring potato tuber yield in the field for bacterial wilt. After the plants in the field are mature, harvest all the test plots, distinguish healthy potato tubers from those infected with bacterial wilt, weigh them separately, and calculate the diseased tuber rate and tuber control effect. The formulas are as follows: Diseased tuber rate (%) = Weight of diseased tubers / Total weight of investigated tubers × 100 Tuber control effect (%) = (Diseased tuber rate in the control plot - Diseased tuber rate in the treatment plot) / Diseased tuber rate in the control plot × 100 3) Result analysis. According to the calculation results of the disease index and plant control effect in Step 1) and the calculation results of the diseased tuber rate and tuber control effect in Step 2), evaluate the field efficacy of the test chemicals for controlling potato bacterial wilt.

2. The method for evaluating the field efficacy of a drug for controlling potato bacterial wilt according to claim 1, characterized in that: The specific steps of Step 1 are as follows: 1) Selection of the test plot. Select a high-incidence disease nursery test plot for potato bacterial wilt with good geographical isolation conditions, convenient transportation, and fertile soil. 2) Selection of seed potatoes. Select virus-free seed potatoes of 50 - 60 g with uniform size. 3) Preparation of the seedling bed. Select a sunny slope plot with flat terrain, healthy and fertile soil, close to the test field, and convenient for management as the germination bed. Level the seedling bed. The bed surface is 3 - 5 cm higher than the ground, and the width of the bed surface is 1.2 m. 4) Place the seed potatoes, remove the rotten, mixed, diseased, inferior and cracked ones, wipe off the sprouted buds on the tubers, place the top of the seed potatoes with buds facing upwards, and place them neatly one by one so that the seed potatoes form a flat surface at the top. There is a 1cm interval between each tuber, the sowing surface is 0.8m wide, and the distance from the edge of the arch shed is 0.2m. 5) Cover with soil and film. After placing the seed potatoes, use a sieve to sift high-quality fertile fine soil, cover it evenly on the surface of the seed potatoes while sifting, with a soil thickness of 3cm. Use a 2.1-2.3m bamboo arch shed, cover it with white plastic film, seal the edges around, clean the drainage ditch, and keep the soil moisture in the shed at 70%-75%.

3. The method for evaluating the field efficacy of a drug for controlling potato bacterial wilt according to claim 1, characterized in that: In step 2) of the present invention, the test variety is the susceptible variety Mira, and the protected row variety is the susceptible E-potato No. 9.

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