Efficient control method for diaphorina citri

Abstract

The invention belongs to the technical field of diaphorina citri prevention and control, and particularly relates to an efficient diaphorina citri prevention and control method. According to the efficient prevention and control method for diaphorina citri, in the citrus planting and growing process, when diaphorina citri appears on citrus, a synergistic insecticide is sprayed, and the synergistic insecticide is prepared by compounding cyprosulfuron, sulfur-fluorine oxime ether, guadipyr or spinetoram as active ingredients and assisting with auxiliary ingredients. According to the efficient prevention and control method for diaphorina citri, active ingredients of a sprayed synergistic insecticide are formed by compounding cyprosulfuron, sufluoxime ether, guadipyr or spinetoram, and an indoor combined effect test shows that the compounded active ingredients show a combined synergistic effect on killing diaphorina citri pests within a certain mass ratio range, so that the effect of preventing and controlling the diaphorina citri is obvious, and the effect of preventing and controlling the diaphorina citri is obvious. The prevention and treatment effect on diaphorina citri can be improved, so that the occurrence and spreading of the citrus liberobacter asiaticum can be blocked to a great extent, and the healthy development of the citrus industry is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of citrus psyllid control, and in particular belongs to a highly efficient citrus psyllid control method. Background Art

[0002] Citrus Huanglongbing is a devastating disease that occurs on citrus throughout the year. Once the disease occurs, it causes the death of young trees, the withering or loss of fruit-bearing ability of mature trees, and even the destruction of the entire orchard. It is one of the most devastating citrus diseases in the world, seriously restricting the healthy development of the citrus industry.

[0003] Citrus psyllid (Diaphorina citriKuwayama) belongs to the family Psyllidae of the order Hemiptera and is the main natural vector of citrus Huanglongbing pathogen. The occurrence and spread of citrus Huanglongbing can be largely prevented by controlling citrus psyllid. Citrus psyllid has a strong reproductive capacity. Adults lay eggs on the young branches of infected trees. After hatching, nymphs begin to suck the sap of the young branches, and then produce a large number of adult carriers. These adult carriers then fly to new plants to spread citrus Huanglongbing.

[0004] At present, chemical control is still the main method for citrus psyllids. However, with the long-term, large-scale and unscientific use of chemical pesticides, citrus psyllids have developed different degrees of resistance to many existing chemical pesticides, resulting in reduced control effects of chemical pesticides, and the disease is rampant again. At the same time, there are also problems of environmental pollution and pesticide residues. Therefore, it is urgent to develop new and efficient agents for the control of citrus psyllids.

[0005] Cyproflanilide (English name: cyproflanilide, CAS: 2375110-88-4) is the first self-created variety of Nantong Taihe. According to the IRAC classification, it belongs to the γ-aminobutyric acid (GABA) gated chloride channel allosteric modulator. It blocks the activated γ-aminobutyric acid chloride channel by allosteric blocking, causing pests to become overexcited and spasm and eventually leading to the death of pests. It can be used to control various pests on crops such as vegetables, fruit trees, corn and soybeans. The existing technology has disclosed that cyproflanilide is mixed with avermectin, which has a synergistic effect and can be used to control hemiptera, lepidoptera and coleoptera pests; it is mixed with diflubenzuron, which has a synergistic effect and is conducive to delaying the resistance of cabbage worms; it is mixed with dinotefuran, which can be used to control pests such as thrips and diamondback moths, with a small amount of medicine and environmentally friendly.

[0006] However, there are no reports on the use of cyfluthrin in combination with thiofluanid, pyraclostrobin or spinetoram for the control of citrus psyllids. Summary of the invention

[0007] The purpose of the present invention is to provide an efficient control method for citrus psyllid, so as to solve the problem that with the long-term, large-scale and unscientific use of chemical pesticides, citrus psyllid has developed different degrees of resistance to many existing chemical pesticides, resulting in reduced control effects of chemical pesticides and the disease becoming rampant again. At the same time, there are also problems of environmental pollution and pesticide residues.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A highly effective method for preventing and controlling citrus psyllids comprises spraying a synergistic insecticide when citrus psyllids appear on citrus during the planting and growth process of citrus. The synergistic insecticide is prepared by combining cyflumifenamide with thiofluanid, pyraclostrobin or spinetoram as active ingredients and supplemented with auxiliary ingredients.

[0010] Preferably, the mass ratio of cyfluthrin to thiofluanid is 1-9:19-1.

[0011] Preferably, the mass ratio of cyfluthrin to pyraclostrobin is 1-12:12-1.

[0012] Preferably, the mass ratio of cyfluthrin to spinetoram is 1-20:15-1.

[0013] Preferably, the auxiliary component is selected from one or more of an inert filler, a dispersant, a wetting agent, a disintegrant, an emulsifier, a solvent, a thickener, a defoaming agent and an antifreeze agent.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] (1) The active ingredients of the synergistic insecticide sprayed in the high-efficiency control method of citrus psyllid of the present invention are compounded by cyfluthrin and thiofluanid, pyraclostrobin or spinetoram. It is found through indoor combined action tests that the compounded active ingredients show a combined synergistic effect on killing citrus psyllid pests within a certain mass ratio range, which can improve the control effect on citrus psyllid, and further can block the occurrence and spread of citrus Huanglongbing to a large extent, and promote the healthy development of the citrus industry.

[0016] (2) The synergistic insecticide sprayed in the high-efficiency control method of citrus psyllid of the present invention has a good control effect on citrus psyllid, can reduce the amount of pesticides used, reduce the control cost and pesticide residues, and alleviate environmental pollution. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is described clearly and completely below.

[0018] Example

[0019] 1. Test pests

[0020] Adult citrus psyllids were collected from citrus plantations and continuously reared in the laboratory for more than 10 generations to form a stable population. During the experiment, adult citrus psyllids of basically the same size were transferred to indoor citrus seedlings that had not been exposed to pesticides. After laying eggs, the adults were transferred and continued to be reared after hatching, with the nymphs being used as test pests.

[0021] 2. Test reagents

[0022] 98% cyfluthrin technical drug, 95% thiofluanid technical drug, 96% pyraclostrobin technical drug, 81.2% spinetoram technical drug, all of the above agents are commercially available.

[0023] The test agent was dissolved in dimethyl sulfoxide and then diluted with a 0.1% Tween-80 aqueous solution to form a single-dose stock solution; multiple groups of ratios were set, and each single dose and each group of mixed ratios were set to 7 mass concentration gradients according to the equal proportion method, with 50 mL of drug solution for each mass concentration. The above agents were prepared and used immediately.

[0024] 3. Test methods

[0025] The leaf dipping method was used. Citrus leaves with uniform distribution of citrus psyllid nymphs and similar leaf sizes were selected, and 1st, 2nd and 4th instar nymphs on the leaves were removed, leaving only 3rd instar nymphs as test objects, and ensuring that there were 15-20 3rd instar nymphs on each leaf.

[0026] The citrus leaves with the third-instar nymphs of the citrus psyllid were immersed in the liquid for 10 seconds, taken out, and the excess liquid was absorbed with filter paper and dried naturally, and then placed in a 9 cm diameter culture dish padded with filter paper, and moisturized with absorbent cotton, sealed with plastic wrap, and holes were pierced in the plastic wrap with an insect pin (the hole diameter was smaller than the body size of the psyllid to prevent escape). Each treatment was repeated 5 times, and the treatment with 0.1% Tween-80 solution was set as a blank control.

[0027] The sealed culture dishes were placed in an artificial climate box at 25±1℃, relative humidity of 70±5%, and a photoperiod of 14L / 10D. After 48 hours, the insects were examined under a microscope. The insects that did not move at all were considered dead if they were touched with an insect pin. The total number of insects and the number of dead insects in each treatment were recorded, and the adjusted mortality rate of each treatment was calculated based on this.

[0028]

[0029] In the above formula: P--mortality rate, unit is %; K--number of dead insects; N--total number of insects treated.

[0030]

[0031] In the above formula: P1--corrected mortality rate, unit is %; P t--Treatment mortality rate, in %; P0--blank control mortality rate, in %.

[0032] 4. Data Analysis

[0033] DPS software was used to perform regression analysis on the logarithmic values ​​of the concentration of each treatment agent and the corrected mortality probability value of each treatment to calculate the LC of each treatment agent. 50 The co-toxicity coefficient (CTC value) of the mixture was calculated using Sun Yunpei's co-toxicity coefficient method, and the synergistic effect of the agent was evaluated based on the calculated co-toxicity coefficient (CTC). The results are shown in Table 1-3.

[0034] Table 1 The combined effect of cyprodinil and thiofluanid on citrus psyllids

[0035] Drug name and ratio <![CDATA[LC 50 (mg / L)]]> ATI TTI CTC Ciprofloxacin 4.4265 100.0000 -- -- Thiofuroxime 11.3916 38.8576 -- -- Cyprodinil fluazifop 1: thiofluanid 19 7.2746 60.8487 41.9147 145.1727 Cyprodinil fluazifop 1: thiofluanid 9 6.4671 68.4464 44.9718 152.1985 Cyprodinil fluazifop 1: thiofluanid 3 4.3320 102.1814 54.1432 188.7245 Cyprodinil fluazifop 1: thiofluanid 1 5.2759 83.9004 69.4288 120.8438 Cyprodinil fluazifop 3: thiofluanid 1 1.3209 335.1124 84.7144 395.5791 Cyprodinil 9: thiofluanid 1 3.7007 119.6125 93.8858 127.4022

[0036] As shown in Table 1, the co-toxicity coefficients of ciprofloxacin and thiofluanid in the mass ratio of 1-9:19-1 were all greater than 120, that is, the combination of ciprofloxacin and thiofluanid showed a synergistic effect on citrus psyllids.

[0037] Table 2 The combined effect of cyprodinil and pyraclostrobin on citrus psyllids

[0038] Drug name and ratio <![CDATA[LC 50 (mg / L)]]> ATI TTI CTC Ciprofloxacin 4.4265 100.0000 -- -- Pentometabolic acid 16.3291 27.1080 -- -- Ciprofloxacin 1: Pentofenac 12 11.2051 39.5043 32.7151 120.7525 Ciprofloxacin 1: Pentofenac 9 8.7002 50.8781 34.3972 147.9134 Ciprofloxacin 1: Pentofenac 3 5.6307 78.6137 45.3310 173.4213 Ciprofloxacin 1: Pentofenac 1 5.1114 86.6005 63.5540 136.2629 Ciprofloxacin 3: Pentofenac 1 4.4209 100.1267 81.7770 122.4387 Ciprofloxacin 9: Pentofenac 1 2.2184 199.5357 92.7108 215.2238 Ciprofloxacin 12: Pentofenac 1 2.9569 149.7007 94.3929 158.5931

[0039] As shown in Table 2, the co-toxicity coefficients of ciprofloxacin and pentamethylenetetracycline in the mass ratio of 1-12:12-1 were all greater than 120, that is, the combination of ciprofloxacin and pentamethylenetetracycline showed a synergistic effect on citrus psyllids.

[0040] Table 3 The combined effect of cyfluthrin and spinetoram on citrus psyllids

[0041] Drug name and ratio <![CDATA[LC 50 (mg / L)]]> ATI TTI CTC Ciprofloxacin 4.4265 100.0000 -- -- Spinetoram 8.7103 50.8191 -- -- Cyprodinil 1: Spinetoram 15 4.2153 105.0103 53.8929 194.8498 Cyprodinil 1: Spinetoram 9 1.8045 245.3034 55.7372 440.1069 Cyprodinil 1: Spinetoram 3 2.6363 167.9058 63.1144 266.0342 Cyprodinil 1: Spinetoram 1 3.4478 128.3862 75.4096 170.2519 Cyprodinil 3: Spinetoram 1 1.9009 232.8634 87.7048 265.5082 Cyprodinil 9: Spinetoram 1 0.8654 511.4976 95.0819 537.9546 Cyprodinil 15: Spinetoram 1 3.1919 138.6792 96.9262 143.0771 Ciprofloxacin 20: Spinetoram 1 3.2577 135.8781 97.6581 139.1366

[0042] As shown in Table 3, the co-toxicity coefficients of ciflumizone and spinetoram in the mass ratio of 1-20:15-1 were all greater than 120, that is, the combination of ciflumizone and spinetoram showed a synergistic effect on citrus psyllids.

[0043] In summary, the active ingredients of the synergistic insecticide sprayed in the efficient control method of citrus psyllid of the present invention are compounded by cyfluthrin and thiofluanid, pyraclostrobin or spinetoram. Through indoor combined action tests, it is found that the compounded active ingredients show a combined synergistic effect on killing citrus psyllid pests within a certain mass ratio range, which can improve the control effect on citrus psyllid, and further can block the occurrence and spread of citrus Huanglongbing disease to a large extent, and promote the healthy development of the citrus industry.

Claims

1. A highly effective method for controlling citrus psyllids, characterized in that: During the planting and growth of citrus, when citrus psyllids appear on citrus, a synergistic insecticide is sprayed. The synergistic insecticide is prepared by combining cyfluthrin with thiofluanid, pyraclostrobin or spinetoram as active ingredients and supplemented with auxiliary ingredients.

2. The highly effective method for controlling citrus psyllid according to claim 1, characterized in that: The mass ratio of cyfluthrin to thiofluanid is 1-9:19-1.

3. The highly effective method for controlling citrus psyllid according to claim 1, characterized in that: The mass ratio of cyfluthrin to pyraclostrobin is 1-12:12-1.

4. The highly effective method for controlling citrus psyllid according to claim 1, characterized in that: The mass ratio of cyfluthrin to spinetoram is 1-20:15-1.

5. The highly effective method for controlling citrus psyllid according to claim 1, characterized in that: The auxiliary components are selected from one or more of an inert filler, a dispersant, a wetting agent, a disintegrant, an emulsifier, a solvent, a thickener, a defoaming agent and an antifreeze agent.

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