Attractant composition for diaphorina citri

Abstract

The invention provides a diaphorina citri attractant composition which is composed of 0.023%-0.977% of sabinene, 0.023%-0.977% of p-cymene and 99% of liquid paraffin, the sabinene and the p-cymene are diaphorina citri attractants with biological activity, and the liquid paraffin plays a role in dilution; when male diaphorina citri adults are specifically attracted, the composition is as follows: 0.977% of sabinene, 0.023% of p-cymene and 99% of liquid paraffin. When female diaphorina citri adults are specifically attracted, the composition is as follows: 0.023% of sabinene, 0.977% of p-cymene and 90% of liquid paraffin. The invention aims to provide the diaphorina citri attractant which is low in price and simple in formula, and the effective components of the diaphorina citri attractant are derived from volatile components of citrus leaves, so that the diaphorina citri attractant has the advantages of no pollution to the environment, no harm to a human body, no residue, no resistance and the like.

Description

Technical Field

[0001] The invention relates to the technical field of pest control, and in particular to application of volatiles from citrus leaves in attracting citrus psyllids and a citrus psyllid attractant combination. Background Art

[0002] The citrus psyllid (Diphorinitri Kuwym) belongs to the Psyllidae family of the order Hemiptera. It is the most serious pest in the citrus industry worldwide because it is the vector of the citrus Huanglongbing pathogen, causing the outbreak of citrus Huanglongbing and dealing a devastating blow to the citrus industry.

[0003] At present, the prevention and control of citrus psyllids mainly relies on chemical pesticides. The correct use of pesticides can effectively control citrus psyllids, but it will also cause harm to natural enemies and other beneficial insects; excessive use of pesticides will also cause problems such as drug resistance, environmental pollution, and pesticide residues, which will increase the cost of prevention and control while causing harm to the environment and people. Therefore, environmentally friendly prevention and control measures such as using plant secondary metabolites, parasitic wasps and natural enemies such as ladybugs, insect pathogenic fungi, and sticky insect boards have been developed. However, these measures have the problem of low efficiency. Summary of the invention

[0004] The present invention aims to provide a citrus psyllid attractant with low price and simple formula, the active ingredients of which are derived from the volatile components of citrus leaves themselves, so the attractant has the advantages of being pollution-free to the environment, harmless to human body, causing no residue, and not producing resistance.

[0005] In view of the deficiencies of the prior art, the present application provides a citrus psyllid attractant combination, which includes the following components in volume percentage: 0.023%-0.977% sabinene, 0.023%-0.977% p-cymene, and 99% liquid paraffin, wherein sabinene and p-cymene are citrus psyllid attractants with biological activity, and the liquid paraffin plays a diluting role.

[0006] Preferably, the citrus psyllid attractant combination, when used to specifically attract male citrus psyllid adults, is composed of: 0.977% sabinene, 0.023% p-cymene, and 99% liquid paraffin.

[0007] When the citrus psyllid attractant combination is used to specifically attract female citrus psyllid adults, the composition is as follows: 0.023% sabinene, 0.977% p-cymene, and 99% liquid paraffin.

[0008] The beneficial effects produced by the present invention are:

[0009] (1) The attractant active substances used in the present invention are all volatile substances from citrus leaves, which do not produce residues, are harmless to the human body, do not pollute the environment, and will not cause citrus psyllids to develop drug resistance.

[0010] (2) The attractant used in the present invention has strong specificity and does not harm other natural enemy insects. When the attractant is used to control citrus psyllids, it does not affect the control effects of biological control and other control measures.

[0011] (3) The attractant can not only be used to control citrus psyllids, but can also be used to detect the occurrence of citrus psyllids and provide timely guidance for control.

[0012] (4) The attractant has a simple formula, low price, and is easy to use, and can be better used in the prevention and control of citrus psyllids. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The number of attractants attracting male citrus psyllid adults;

[0014] Figure 2 The number of attractants attracting female citrus psyllid adults;

[0015] Figure 3 This is a schematic diagram of the structure of a "Y" type olfactometer.

[0016] Explanation of the reference numerals: 1. Insect entrance; 2. Main arm; 3. Selection arm; 4. Flavor source bottle; 5. Distilled water washing bottle; 6. Flow meter; 7. Activated carbon; 8. Air pump. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0018] A citrus psyllid attractant combination, using a headspace adsorption-solid phase microextraction method to collect volatile substances released by citrus tender shoots and leaves during the shoot period, and analyzed by gas chromatography-mass spectrometry, and dozens of volatile substance components were identified based on the spectral library map and standard sample retention time comparison analysis, and then these components were used to attract citrus psyllid adults one by one. As a result, two chemical components that can specifically attract citrus psyllids were found, and these two substances are sabinene and p-cymene. In the existing patented technology, myrcene can also be used as an attractant component for citrus psyllids, and the ratio between the components is determined by conducting a mixed experimental test on sabinene and cymene.

[0019] Sabinene, molecular formula: C 10 H 16 , molecular weight: 136.23; CAS number: 3387-41-5; its structural formula is shown below. Sabinene is a natural product that is widely present in volatile compounds of plants. It is a compound with a unique aroma and is often used as a component of spices or flavors.

[0020]

[0021] p-Cymene, molecular formula: C 10 H 14 , molecular weight: 134.22; CAS number: 99-87-6; it is a colorless transparent liquid, insoluble in water, soluble in organic solvents such as ethanol, ether, acetone, chloroform, etc., mainly used in organic synthesis and preparation of paint thinners.

[0022]

[0023] The present invention adopts a "Y"-shaped olfactometer method to carry out a directional behavior reaction test on citrus psyllids in a laboratory.

[0024] When in use, first turn on the vacuum pump, control the air flow rate of the left and right selection arms 3 of the Y-tube to be 100mL / min, and start the test after ventilation for 3 minutes. The two selection arms 3 of the Y-tube are the treatment group and the control group respectively. The treatment group is 20ul of active substance dripped into the center of the cotton ball. Each active substance is prepared into three concentrations of 0.1ul / ml, 1ul / ml, and 10ul / ml with liquid paraffin. The control group is dripped into the center of the cotton ball. The male and female citrus psyllids used are 15 days old or older. Each insect is connected to the main arm. When it crawls into more than one-third of the selection arm and stays for more than 1min, it is considered to be a choice. If it does not make a choice within 5 minutes after being connected, it is considered to be no choice. Every 20 heads are repeated in a group, and a total of three groups are repeated. After each test of 10 heads, the olfactometer is rotated 180°. After one repetition, the olfactometer is cleaned with 75% ethanol and allowed to dry naturally before the next experiment.

[0025] The same concentration of sabinene and cymene were used in a comparative experiment with liquid paraffin to attract citrus psyllids. The previous test results showed that sabinene had a significantly higher attracting effect on citrus psyllids than cymene. Therefore, in the subsequent attractant mixing ratio exploration test, sabinene was selected as a control. Myrcene in the prior art can also be used as an attractant for citrus psyllids. In the following test, myrcene and the combination of myrcene and the two attractants of the present invention were used as a comparison group for attractant experiments.

[0026] Two combinations of myrcene and sabinene, and myrcene and cymene with different concentration ratios were used for attraction experiments. In the experiment, the ratio of myrcene to sabinene was , and the ratio of myrcene to cymene was .

[0027] Example 1

[0028] The treatment groups were prepared with cymene and sabinene in liquid paraffin as solvents at concentrations of 0.1ul / ml, 1ul / ml, and 10ul / ml, respectively, and the control group was an equal volume of liquid paraffin. The treatment group and the control group were added to the center of the cotton ball, and the cotton ball was placed in the odor source bottle 4. Then, the selectivity was determined using a "Y" type olfactometer. The selectivity effects of male and female adults of citrus psyllids on different compounds are shown in Tables 1 and 2.

[0029] Table 1 Selectivity of male citrus psyllids to different compounds

[0030] Serial number Name of volatile matter Concentration (ul / ml) Treatment selection rate (%) Control selection rate (%) 1 Sabinene 0.1 52 48 2 Sabinene 1 67 33 3 Sabinene 10 73 27 4 p-Cymene 0.1 55 45 5 p-Cymene 1 77 23 6 p-Cymene 10 75 25

[0031] Table 2 Selectivity of female citrus psyllids to different compounds

[0032] Serial number Name of volatile matter Concentration (ul / ml) Treatment selection rate (%) Control selection rate (%) 1 Sabinene 0.1 55 45 2 Sabinene 1 55 45 3 Sabinene 10 72 28 4 p-Cymene 0.1 47 53 5 p-Cymene 1 57 43 6 p-Cymene 10 80 20

[0033] Example 2

[0034] Use indoors Figure 3 The Y-type olfactometer shown in the figure detects the attractant effect on citrus psyllid adults. Use a pipette to draw 100ul of attractants of different ingredients and ratios and drop them in the center of a cotton ball and place it at one end of the Y-type olfactometer. Use reagent No. 1 in Table 3 as a control at the other end to capture citrus psyllid adults. Select an adult with better crawling ability each time. When the adult crawls into more than one-third of the selection arm and stays for more than 1 minute, it is considered a choice. If no choice is made within 5 minutes after access, it is considered no choice. Male and female insects are tested separately, with 20 heads as a group and repeated for a total of three groups. The olfactometer is rotated 180° for every 10 heads tested. After one repetition, the olfactometer is cleaned with 75% ethanol and allowed to dry naturally before the next experiment. The results are shown in Tables 3 to 5.

[0035] Table 3 Mixed reagent ingredients and ratios

[0036] Reagent No. Mixed reagent ingredients and ratio 1 Sabinene 1%, liquid paraffin 99% 2 Myrcene 1%, liquid paraffin 99% 3 Myrcene 0.5%, sabinene 0.5%, liquid paraffin 99% 4 Sabinene 0.5%, p-cymene 0.5%, liquid paraffin 99% 5 Sabinene 0.865%, p-cymene 0.135%, liquid paraffin 99% 6 Sabinene 0.135%, p-cymene 0.865%, liquid paraffin 99% 7 Sabinene 0.977%, p-cymene 0.023%, liquid paraffin 99% 8 Sabinene 0.023%, p-cymene 0.977%, liquid paraffin 99%

[0037] Table 4 Olfactory responses of male citrus psyllids to mixed reagents

[0038] Reagent No. Treatment selection rate (%) Control selection rate (%) 2 54 46 3 52 48 4 58 42 5 63 37 6 37 63 7 63 37 8 52 48

[0039] Table 5 Selectivity of female citrus psyllids to different mixed reagents

[0040]

[0041]

[0042] Example 3

[0043] The results in Example 2 show that reagents 5, 7, and 8 have good attracting effects on citrus psyllid adults. Therefore, reagents 5, 7, and 8 are selected for comparison to determine the best attracting effect and ratio for citrus psyllids. The implementation method is the same as that in Example 1. The treatment group and the control group are added to the center of the cotton ball, and the cotton ball is placed in the odor source bottle 4. Then, the selectivity is determined using a "Y" type olfactometer. The selectivity of male and female citrus psyllid adults to different compounds is shown in Table 1. Figure 1 and Table 6 with Figure 2 and Table 7.

[0044] Table 6 Selectivity of male citrus psyllids to different compounds

[0045] Treatment Group Control group Treatment selection rate (%) Control selection rate (%) 5 8 39 21 7 8 38 22 7 5 40 20

[0046] Table 7 Selectivity of female citrus psyllids to different compounds

[0047] Treatment Group Control group Treatment selection rate (%) Control selection rate (%) 5 8 21 39 7 8 25 35 7 5 36 24

[0048] The above results show that the attractant No. 7 has the best attracting effect on male citrus psyllid adults, and the attractant No. 8 has the best attracting effect on female citrus psyllid adults.

[0049] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A citrus psyllid attractant combination, characterized in that: The citrus psyllid attractant comprises the following components in volume percentage: 0.023%-0.977% of sabinene, 0.023%-0.977% of p-cymene and 99% of liquid paraffin.

2. The citrus psyllid attractant combination according to claim 1, characterized in that: The citrus psyllid attractant comprises the following components in percentage by volume: 0.977% sabinene, 0.023% p-cymene and 99% liquid paraffin.

3. The citrus psyllid attractant combination according to claim 1, characterized in that: The citrus psyllid attractant comprises the following components in volume percentage: 0.023% sabinene, 0.977% p-cymene and 99% liquid paraffin.

4. Use of the citrus psyllid attractant combination as claimed in claim 2 as an attractant for male citrus psyllid.

5. Use of the citrus psyllid attractant combination as claimed in claim 3 as an attractant for female citrus psyllid.

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