A biological pesticide for preventing and controlling pineapple heart rot

Abstract

The present invention belongs to the technical field of pesticides, and specifically belongs to a biological pesticide for preventing and treating pineapple heart rot. A biological pesticide for preventing and treating pineapple heart rot, wherein the active ingredient is a compound of shinazomib and fluazole activated ester, fluoxastrobin or isoprenaline. After shinazomib is compounded with fluazole activated ester, fluoxastrobin or isoprenaline, the agent exhibits a synergistic effect when inhibiting the growth of tobacco phytophthora hyphae, and can be used to prevent and treat diseases such as pineapple heart rot caused by tobacco phytophthora, and can improve the prevention and treatment effect on tobacco phytophthora. In addition, compared with a single active ingredient, the generation of drug resistance of pathogens can be delayed.

Description

Technical Field

[0001] The invention belongs to the technical field of pesticides, and in particular belongs to a biological pesticide for preventing and treating pineapple heart rot. Background Art

[0002] Pineapple heart rot is a soil-borne disease that seriously harms pineapples. The pathogen can infect and harm pineapples throughout their entire growth period, mainly affecting seedlings. In the early stages of the disease, the leaves become slightly darker and duller, brown stripes begin to appear at the base of the stem, and the heart leaves are easily pulled up. In the later stages of the disease, the entire plant dies, affecting the yield and quality of the pineapple.

[0003] According to research reports, the pathogen of pineapple heart rot is mainly fungal diseases of the genus Phytophthora, mainly: tobacco phytophthora, camphor phytophthora, palm phytophthora and citrus brown rot phytophthora. Chemical pesticides have the advantages of wide application range and high control efficiency, and are widely used in the prevention and control of pests and diseases, and pineapple heart rot is no exception. Commonly used agents for pineapple heart rot include: carbendazim, methyl thiophanate, benomyl and difopidine. However, while chemical pesticides bring high control effects, they also cause many problems due to long-term and large-scale use: causing the continuous enrichment of pesticide residues in pineapple leaves and soil, which is harmful to animals and soil microbial environment; long-term use will also make pineapple heart rot prone to drug resistance. Now, due to the long-term single use of the same fungicide or several fungicides with the same fungicide mechanism, pineapple heart rot has developed different degrees of drug resistance, resulting in reduced control effect, and then increasing the amount of agent application, forming a vicious circle. Therefore, it is necessary to develop a new agent with high control effect and the ability to delay the development of pathogen resistance.

[0004] Compounding different pesticides is an effective way to develop new pesticides. At present, there are no reports on compounding sinocycline with fluazifop-butyl, fluoxastrobin or isoprene.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to provide a biological pesticide for preventing and treating pineapple heart rot, thereby overcoming the problems existing when a single agent is used.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] The first object of the present invention is to provide a biological pesticide for preventing and controlling pineapple heart rot, wherein the active ingredient is a compound of sinocycline and fluazifop-butyl, fluoxastrobin or isoprofenamide.

[0009] Preferably, the mass ratio of the shinazolinmycin to the fluazole activated ester is 1-10:10-1.

[0010] Preferably, the mass ratio of shinazomib to fluoxastrobin is 1-40:5-1.

[0011] Preferably, the mass ratio of the shinazomib to isoprenaline is 1-20:15-1.

[0012] The second object of the present invention is to provide a biological pesticide preparation, comprising the active ingredients and auxiliary ingredients allowed to be added in pesticide science.

[0013] Preferably, the mass of the active ingredient accounts for 1.5-60% of the total mass of the biopesticide preparation.

[0014] The third object of the present invention is to provide the use of the biopesticide preparation in preventing and controlling fungal diseases caused by tobacco phytophthora.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) After the present invention combines shinazomib with fluazifop-butyl, fluoxastrobin or isoprene, the agent exhibits a synergistic effect in inhibiting the growth of tobacco phytophthora hyphae, and can be used to prevent and control diseases such as pineapple heart rot caused by tobacco phytophthora, and can improve the control effect on tobacco phytophthora.

[0017] (2) Compared with a single active ingredient, the biopesticide of the present invention can delay the development of drug resistance in pathogens. DETAILED DESCRIPTION

[0018] The present invention can be better understood according to the following examples. However, it is easy for those skilled in the art to understand that the contents described in the examples are only used to illustrate the present invention, and should not and will not limit the present invention described in detail in the claims.

[0019] Example :Pharmaceutical Screening

[0020] 1. Test strain: isolated from pineapple heart rot strain, identified as tobacco phytophthora, and preserved on V8 juice agar medium.

[0021] 2. V8 juice agar medium: Add 200 mL of V8 juice and 3 g of CaCO3 to 800 mL of distilled water, mix well, adjust the pH to 7.2, add 15 g of agar, heat until the agar is completely dissolved, and sterilize with high-pressure steam at 121°C for 20 min.

[0022] 3. Test reagents

[0023] 95% sphenantheramycin technical, 98% fluazifop-butyl technical, 94% fluoxastrobin technical, 95% isoprofenamide technical, all of the above agents are commercially available.

[0024] The test agent was first dissolved in dimethyl sulfoxide and then diluted with 0.1% Tween-80 aqueous solution to prepare a single-dose stock solution. Multiple groups of proportions were set, and each single dose and proportioned mixture was set with 5 mass concentration gradients according to the equal ratio method.

[0025] 4. Test methods

[0026] The mycelium growth rate method was used. 9 mL of pre-melted V8 juice agar medium was added to a sterile conical flask, and 1 mL of the drug solution was quantitatively drawn from low concentration to high concentration, respectively, and added to the above conical flasks, and then poured into a culture dish with a diameter of 9 cm after being fully shaken to prepare drug-containing plates of corresponding concentrations; and a treatment without drug was set as a blank control, and 10 replicates were set for each treatment.

[0027] Use a 5mm diameter puncher to cut a bacterial cake at the edge of the test strain colony, inoculate it in the center of the drug-containing plate and the blank control plate, cover the plate with a lid and culture it in a 26℃ constant temperature box for 7 days. Measure the colony diameter using the cross method and calculate the inhibition rate of mycelium growth under different treatments.

[0028]

[0029] 5. Data analysis: DPS software was used for data statistical analysis. The logarithmic value of fungicide concentration was taken as x and the corresponding probability value of mycelium growth inhibition rate was taken as y for linear regression. The toxicity regression equation and the toxicity EC value of the agent to the target pathogen were obtained. 50 The co-toxicity coefficient (CTC) was calculated according to the Sun Yunpei method.

[0030]

[0031] In the above formula: ATI--the toxicity index of the mixture; S--the LC of the standard agent 50 , the unit is mg / L; M--LC of the mixture 50 , unit is mg / L.

[0032] TTI=TI A ×P A +TI B ×P B

[0033] In the above formula: TTI-theoretical toxicity index of the mixture; TI A --Toxicity index of A agent; P A --The percentage of agent A in the mixture, in percentage (%); TI B --Toxicity index of agent B; PB --The percentage of agent B in the mixture, in percentage (%).

[0034]

[0035] In the above formula: CTC--co-toxicity coefficient; ATI--actual toxicity index of the mixture; TTI--theoretical toxicity index of the mixture.

[0036] 6. Measurement results

[0037] The synergistic effect of the drug was evaluated based on the calculated co-toxicity coefficient (CTC), CTC≤80 was antagonistic, 80<CTC<120 was additive, and CTC≥120 was synergistic. The results are shown in Table 1-3.

[0038] Table 1 Indoor bioactivity test of the combination of shinazolin and fluazifop-activated ester against Phytophthora nicotianae

[0039] Drug name and ratio EC50(mg / L) ATI TTI CTC Shinqin 6.5198 100.0000 -- -- Fluorazole activated ester 16.6141 39.2426 -- -- Shenqinomycin 1: Fluoxetine activated ester 10 11.2873 57.7623 44.7660 129.0316 Shenqinomycin 1: Fluoxetine activated ester 5 9.2486 70.4950 49.3688 142.7926 Shenqinomycin 1: Fluoxetine activated ester 3 4.9756 131.0355 54.4319 240.7327 Shenqinomycin 1: Fluoxetine activated ester 1 5.9073 110.3685 69.6213 158.5270 Shenqinomycin 3: Fluoxetine activated ester 1 2.6587 245.2251 84.8106 289.1443 Shenqinomycin 5: Fluoxetine activated ester 1 4.1639 156.5792 89.8738 174.2212 Shenqinomycin 10: Fluoxetine activated ester 1 1.6192 402.6556 94.4766 426.1962

[0040] As shown in Table 1, after the combination of shinazolin and fluazole activated ester, the co-toxicity coefficient to tobacco phytophthora was greater than 120 within the mass ratio of 1-10:10-1, showing a synergistic effect.

[0041] Table 2 Indoor bioactivity test of the combination of shinazomib and fluoxastrobin against Phytophthora nicotianae

[0042] Drug name and ratio EC50(mg / L) ATI TTI CTC Shinqin 6.5198 100.0000 -- -- Fluoxastrobin 2.7643 235.8572 -- -- Shenqinmycin 1: Fluoxastrobin 5 2.2555 289.0623 213.2143 135.5736 Shenqinmycin 1: Fluoxastrobin 1 1.9104 341.2793 167.9286 203.2288 Shenqinomycin 5: Fluoxastrobin 1 1.4331 454.9438 122.6429 370.9501 Shenqinmycin 10: Fluoxastrobin 1 3.0724 212.2054 112.3507 188.8778 Shenqinmycin 20: Fluoxastrobin 1 4.1290 157.9026 106.4694 148.3080 Shenqinmycin 30: Fluoxastrobin 1 2.5889 251.8367 104.3825 241.2633 Shenqinmycin 40: Fluoxastrobin 1 4.7924 136.0446 103.3136 131.6812

[0043] As shown in Table 2, after the combination of shinazomib and fluoxastrobin, the co-toxicity coefficient against tobacco phytophthora was greater than 120 within the mass ratio of 1-40:5-1, showing a synergistic effect.

[0044] Table 3 Indoor bioactivity test of the combination of shinazomib and isoprofenamide against Phytophthora nicotianae

[0045] Drug name and ratio EC50(mg / L) ATI TTI CTC Shinqin 6.5198 100.0000 -- -- Iprothiocarb 10.9935 59.3060 -- -- Shenqinomycin 1: Iprofen 15 7.5556 86.2910 61.8493 139.5180 Shenqinomycin 1: Iprofenamide 10 4.8049 135.6906 63.0054 215.3635 Shenqinomycin 1: Iprofen 5 3.5937 181.4230 66.0883 274.5162 Shenqinomycin 1: Iprofen 1 6.6882 97.4821 79.6530 122.3835 Shenqinomycin 5: Iprofen 1 1.3554 481.0241 93.2177 516.0225 Shenqinomycin 10: Iprofen 1 5.2330 124.5901 96.3005 129.3763 Shenqinomycin 20: Iprofen 1 2.6764 243.6033 98.0622 248.4172

[0046] As shown in Table 3, after the combination of sinocycline and isoprenaline, the co-toxicity coefficients against tobacco phytophthora were greater than 120 within the mass ratio of 1-20:15-1, showing a synergistic effect.

[0047] In summary, after the present invention combines shinazolin with fluazole activated ester, fluoxastrobin or isoprene, the agent shows a synergistic effect in inhibiting the growth of tobacco phytophthora hyphae, and can be used to prevent and control diseases such as pineapple heart rot caused by tobacco phytophthora, and can improve the control effect on tobacco phytophthora.

[0048] The above is only a preferred embodiment of the present invention. Those skilled in the art may make appropriate improvements without departing from the principle of the present invention. These improvements are also within the protection scope of the present invention.

Claims

1. A biological pesticide for preventing and treating pineapple heart rot, characterized in that: The effective component is prepared by compounding shinazolinmycin and fluazole activated ester, and the mass ratio of shinazolinmycin to fluazole activated ester is 1-10:10-1.

Images