A highly effective method for controlling citrus psylla

Abstract

The application belongs to the technical field of citrus psylla control, and particularly relates to a high-efficiency citrus psylla control method. The high-efficiency citrus psylla control method comprises the following steps: during the cultivation and growth of citrus, when citrus psylla appears on the citrus, a synergistic insecticide is sprayed, wherein the synergistic insecticide is prepared by compounding cycloprothrin, sulfluramid, spirodien, or ethyl spinosyn as active ingredients, and by adding auxiliary ingredients. In the high-efficiency citrus psylla control method, the active ingredients of the synergistic insecticide sprayed are compounded by cycloprothrin, sulfluramid, spirodien, or ethyl spinosyn. Through indoor joint action tests, it is found that the compounded active ingredients show a joint synergistic effect on killing citrus psylla pests within a certain mass ratio range, can improve the control effect on citrus psylla, and can greatly block the occurrence and spread of citrus Huanglongbing, thereby promoting the healthy development of the citrus industry.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of citrus psyllid prevention and control, and particularly relates to a high-efficiency citrus psyllid prevention and control method. BACKGROUND

[0002] Citrus Huanglongbing is a devastating disease that occurs on citrus trees throughout the year. After the disease occurs, it can cause young trees to die, mature or die, or lose the ability to bear fruit, and even destroy the entire garden. It is one of the most devastating citrus diseases in the world, which seriously restricts the healthy development of the citrus industry.

[0003] Diaphorina citri Kuwayama belongs to the family of Psylloidea in the order of Hemiptera, and is the main natural transmission medium of the citrus Huanglongbing pathogen. By preventing and controlling citrus psyllids, the occurrence and spread of citrus Huanglongbing can be largely prevented. Citrus psyllids have strong reproductive ability. Adult insects lay eggs on infected tender shoots, and after the larvae hatch, they start sucking the juice of the tender shoots, and then produce a large number of adult insects carrying the disease, which fly to new plants to spread the citrus Huanglongbing.

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

[0005] Cyproflanilide (English name: cyproflanilide, CAS: 2375110-88-4) is the first self-invented variety of Nantong Taiko. According to the IRAC classification, it belongs to the γ-aminobutyric acid (GABA) gate chloride channel allosteric modulator. By allosteric blocking of activated γ-aminobutyric acid chloride channels, pests are over-excited and spastic and eventually die. It can be used to control a variety of pests on vegetables, fruit trees, corn and soybean crops. The prior art has disclosed that cyproflanilide is mixed with emamectin benzoate to have a synergistic effect, which can be used to control pests in the orders of Hemiptera, Lepidoptera and Coleoptera; mixed with chlorbenzuron to have a synergistic effect, which is beneficial to delaying the development of resistance to cabbage worms; and mixed with dinotefuran to control thrips and diamondback moth and other pests, with less dosage and environmental friendliness.

[0006] However, there is no related report on the use of cyproflanilide mixed with sulfluramid, spirodines or spinosyn to control citrus psyllids. SUMMARY

[0007] The present application aims to provide a high-efficiency prevention and treatment method for citrus psylla, so as to solve the problems of different degrees of drug resistance of citrus psylla to existing chemical pesticides, reduced prevention and treatment effect of chemical pesticides, rampant disease, environmental pollution and pesticide residues caused by long-term, large-scale and unscientific use of chemical pesticides.

[0008] To achieve the above-mentioned purpose, the present application provides the following technical solutions.

[0009] A high-efficiency prevention and treatment method for citrus psylla, wherein when citrus psylla appears on citrus during the cultivation and growth of citrus, a synergistic insecticide is sprayed, the synergistic insecticide is prepared by compounding cycloprothrin, sulfoxaflor, spirodiclofen or spinetoram as active ingredients, and supplemented by auxiliary ingredients.

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

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

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

[0013] Preferably, the auxiliary ingredients are selected from one or more of inert fillers, dispersants, wetting agents, disintegrants, emulsifiers, solvents, thickening agents, antifoaming agents and antifreezing agents.

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

[0015] (1) The active ingredients of the synergistic insecticide sprayed in the high-efficiency prevention and treatment method for citrus psylla of the present application are compounded by cycloprothrin, sulfoxaflor, spirodiclofen or spinetoram, and through indoor joint action test, it is found that the compounded active ingredients show joint synergistic effect in a certain mass ratio range for killing citrus psylla pests, which can improve the prevention and treatment effect on citrus psylla, and further can greatly block the occurrence and spread of citrus Huanglongbing disease, and promote the healthy development of citrus industry.

[0016] (2) The synergistic insecticide sprayed in the high-efficiency prevention and treatment method for citrus psylla of the present application has good prevention and treatment effect on citrus psylla, which can reduce the amount of pesticide, reduce the prevention and treatment cost and pesticide residues, and reduce environmental pollution. DETAILED DESCRIPTION

[0017] The technical solutions of the present application are described below.

[0018] Example

[0019] 1. Test pests

[0020] The citrus psylla adults in the citrus orchard were collected, and continuously reared in the laboratory to form stable population for more than 10 generations. In the experiment, the citrus psylla adults with basically uniform size were transferred to the indoor citrus seedlings which were not contacted with pesticides, and the adults were transferred after oviposition. The nymphs were continuously reared after hatching, and the nymphs were used as the test pests.

[0021] 2. Test agents

[0022] 98% cyflumetofen technical agent, 95% sulfluramid technical agent, 96% spirodiclofen technical agent, and 81.2% spinetoram technical agent were all commercially available.

[0023] The test agents were dissolved in dimethyl sulfoxide and then diluted with 0.1% Tween-80 aqueous solution to form single-dose stock solutions. Multiple groups of combinations were set, and each single dose and each group of combined agents were set with 7 mass concentration gradients according to the equal ratio method. Each mass concentration of the liquid was 50 mL, and the above agents were prepared immediately before use.

[0024] 3. Test method

[0025] The leaf dipping method was used. The citrus leaves with uniform distribution of citrus psylla nymphs and similar leaf size were selected, and the 1st instar, 2nd instar and 4th instar and above nymphs on the leaves were removed, and only the 3rd instar nymphs were reserved as the test objects, and it was ensured that each leaf had 15-20 3rd instar nymphs.

[0026] The citrus leaves with 3rd instar nymphs of citrus psylla were immersed in the liquid for 10s, taken out, and the excess liquid was absorbed with filter paper and then naturally dried. Then, the leaves were placed in a 9cm diameter culture dish padded with filter paper, and the leaves were kept moist with absorbent cotton and sealed with plastic wrap. The plastic wrap was punctured with an insect needle (the hole diameter was smaller than the size of the psylla to prevent escape). Each treatment was repeated 5 times, and a treatment with 0.1% Tween-80 solution was set as a blank control.

[0027] The sealed culture dishes were placed in an artificial climate chamber with a temperature of 25±1℃, a relative humidity of 70±5%, and a photoperiod of 14L / 10D. After 48h, the dead insects were recorded by microscopy, and the dead insects were recorded by touching the insect body with an insect needle. The total number of insects and the number of dead insects in each treatment were recorded, and the corrected mortality rate of each treatment was calculated.

[0028]

[0029] In the above formula, P represents the mortality rate, unit: %; K represents the number of dead insects; and N represents the total number of insects in the treatment.

[0030]

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

[0032] 4. Data analysis

[0033] The DPS software was used for regression analysis of the logarithmic values of the concentrations of each treatment agent and the corrected mortality probability values of each treatment, so as to calculate the LC 50 The co-toxicity coefficient (CTC value) of the mixed agent was calculated by using the co-toxicity coefficient method of Sun Yunpei, and the synergistic effect of the agent was evaluated according to the calculated co-toxicity coefficient (CTC), and the results are shown in Tables 1-3.

[0034] Table 1 Synergistic effect of cyflumetofen and sulfuryl fluoroxy ether on Diaphorina citri

[0035] Pesticide name and ratio LC 50 (mg / L) ATI TTI CTC Cycloprothrin 4.4265 100.0000 -- -- Sulfluramid 11.3916 38.8576 -- -- Cycloprothrin 1 : Sulfluramid 19 7.2746 60.8487 41.9147 145.1727 Cycloprothrin 1 : Sulfluramid 9 6.4671 68.4464 44.9718 152.1985 Cycloprothrin 1 : Sulfluramid 3 4.3320 102.1814 54.1432 188.7245 Cycloprothrin 1 : Sulfluramid 1 5.2759 83.9004 69.4288 120.8438 Cycloprothrin 3 : Sulfluramid 1 1.3209 335.1124 84.7144 395.5791 Cycloprothrin 9 : Sulfluramid 1 3.7007 119.6125 93.8858 127.4022

[0036] As shown in Table 1, the co-toxicity coefficients of cyflumetofen and sulfuryl fluoroxy ether in the mass ratio of 1-9:19-1 are all greater than 120, that is, cyflumetofen and sulfuryl fluoroxy ether after compounding show a synergistic effect on Diaphorina citri.

[0037] Table 2 Synergistic effect of cyflumetofen and spirodiametofen on Diaphorina citri

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

[0039] As shown in Table 2, the co-toxicity coefficients of cyflumetofen and spirodiametofen in the mass ratio of 1-12:12-1 are all greater than 120, that is, cyflumetofen and spirodiametofen after compounding show a synergistic effect on Diaphorina citri.

[0040] Table 3 Synergistic effect of cyflumetofen and spinetoram on Diaphorina citri

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

[0042] As shown in Table 3, the co-toxicity coefficients of cyflumetofen and spinetoram in the mass ratio of 1-20:15-1 are all greater than 120, that is, cyflumetofen and spinetoram after compounding show a synergistic effect on Diaphorina citri.

[0043] In summary, the active ingredients of the synergistic insecticide sprayed in the method for efficiently preventing and treating Diaphorina citri in the application are compounded by cyflumetofen and sulfuryl fluoroxy ether, spirodiametofen or spinetoram. Through indoor synergistic effect test, it is found that the compounded active ingredients show a synergistic effect on killing Diaphorina citri pests in a certain mass ratio range, can improve the prevention and treatment effect on Diaphorina citri, and can greatly block the occurrence and spread of citrus Huanglongbing, 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 trees, a synergistic insecticide is sprayed. The synergistic insecticide is prepared by combining cyprofen and thioflumezine as active ingredients, supplemented with auxiliary ingredients. The mass ratio of cyprofen to thioflumezine is 1-9:19-1.

2. The highly efficient control method for citrus psyllids according to claim 1, characterized in that, The auxiliary components are selected from one or more of inert fillers, dispersants, wetting agents, disintegrants, emulsifiers, solvents, thickeners, defoamers, and antifreeze agents.

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