Application of Span 20 in repelling solenopsis invicta

Abstract

The invention discloses application of Span 20 in repelling solenopsis invicta, and belongs to the technical field of pest repelling agents. The invention discloses a repelling effect of 1-octadecene and Span 20 on solenopsis invicta, in order to clarify a behavior regulation effect of two pheromones on the solenopsis invicta, ham sausages and filter paper sheets treated by the 1-octadecene and the Span 20 are placed around a solenopsis invicta nest, and contact, identification and behaviors of the solenopsis invicta on the ham sausages and the filter paper sheets are observed. Test results show that 1-octadecene and Span 20 can trigger contact and identification of solenopsis invicta so as to generate a repelling behavior, a burying behavior and a corpse burying behavior. According to different behavioristics differences of the solenopsis invicta, the behavior regulation and control effects of the 1-octadecene and the Span 20 on the solenopsis invicta are excavated and verified, and a new thought can be provided for prevention and control of the solenopsis invicta through excavation of the two pheromones.

Description

Technical Field

[0001] The present invention relates to the technical field of pest repellents, and particularly to the application of Span 20 in repelling Solenopsis invicta Buren. Background Art

[0002] Solenopsis invicta Buren has biological characteristics such as strong competitiveness, a wide range of food, a high reproduction rate, and a fast spread speed. It will endanger human health, affect agricultural production, threaten public safety, and damage the ecological balance. It is one of the world's recognized hundred most threatening alien invasive species. Common control methods include plant quarantine, chemical control, biological control, and physical control. However, these four methods have many deficiencies, such as high operation difficulty, drug resistance, environmental pollution, killing of non-target organisms, poor control effect, and species invasion. Insect pheromones have the advantages of strong pertinence, no environmental pollution, no drug resistance, and no killing of non-target organisms in the control of agricultural and forestry pests, and have broad application and development prospects in the research of new pesticides. Many behavioral activities of Solenopsis invicta Buren are regulated by pheromones. Therefore, using pheromones to control Solenopsis invicta Buren is a new exploration and also a research hotspot for Solenopsis invicta Buren control at present. Summary of the Invention

[0003] The purpose of the present invention is to provide the application of Span 20 in repelling Solenopsis invicta Buren to solve the problems existing in the above-mentioned prior art.

[0004] To achieve the above purpose, the present invention provides the following solutions:

[0005] One of the technical solutions of the present invention is the application of Span 20 in repelling Solenopsis invicta Buren.

[0006] Another technical solution of the present invention is the application of Span 20 as a Solenopsis invicta Buren repellent or in the preparation of a Solenopsis invicta Buren repellent.

[0007] A third technical solution of the present invention is a Solenopsis invicta Buren repellent comprising Span 20.

[0008] A fourth technical solution of the present invention is a method for repelling Solenopsis invicta Buren, which uses Span 20 or the Solenopsis invicta Buren repellent to repel Solenopsis invicta Buren.

[0009] Based on the above technical solutions, the present invention has the following technical effects:

[0010] The present invention discloses the repellent effects of 1-octadecene and Span 20 on red imported fire ants. In order to clarify the behavioral regulation effects of the two pheromones on red imported fire ants, the ham sausages and filter papers treated with 1-octadecene and Span 20 were placed around the red imported fire ant nests, and the contact, recognition and behaviors of red imported fire ants towards them were observed. The test results show that 1-octadecene and Span 20 can trigger the contact and recognition of red imported fire ants, thereby generating repellent behaviors, burying behaviors and corpse-burying behaviors. Based on the different behavioral differences of red imported fire ants, the present invention has explored and verified the behavioral regulation effects of 1-octadecene and Span 20 on red imported fire ants. The exploration of the two pheromones can provide new ideas for the prevention and control of red imported fire ants. Brief Description of the Drawings

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0012] Figure 1 Repellent effect of 1-octadecene with different dilution multiples on red imported fire ants (1 h).

[0013] Figure 2 Repellent effect of Span 20 with different dilution multiples on red imported fire ants (1 h).

[0014] Figure 3 Repellent rate of 1-octadecene with different dilution multiples on red imported fire ants (1 h).

[0015] Figure 4 Repellent rate of Span 20 with different dilution multiples on red imported fire ants (1 h).

[0016] Figure 5 Burying behavior of red imported fire ants towards 1-octadecene.

[0017] Figure 6 Burying behavior of red imported fire ants towards Span 20.

[0018] Figure 7 Burying behavior of red imported fire ants towards 1-octadecene with different dilution multiples. Among them, T1 is the original solution of 1-octadecene; T2 is the 1-octadecene solution diluted 3 times; T3 is the 1-octadecene solution diluted 6 times; CK1 is the water control; CK2 is the n-hexane control.

[0019] Figure 8 Burying behavior of red imported fire ants towards Span 20 with different dilution multiples. Among them, T1 is the original solution of Span 20; T2 is the Span 20 solution diluted 3 times; T3 is the Span 20 solution diluted 6 times; CK1 is the water control; CK2 is the n-hexane control.

[0020] Figure 9 To bury the red imported fire ants with different dilution multiples of 1-octadecene and observe the change in their numbers.

[0021] Figure 10 To bury the red imported fire ants with different dilution multiples of Span 20 and observe the change in their numbers.

[0022] Figure 11 To compare the numbers of red imported fire ants that participated in burying and those that did not participate in burying with different dilution multiples of 1-octadecene. Among them, A is the number of red imported fire ants that participated in burying, and B is the number of red imported fire ants that did not participate in burying.

[0023] Figure 12 To compare the numbers of red imported fire ants that participated in burying and those that did not participate in burying with different dilution multiples of Span 20. Among them, A is the number of red imported fire ants that participated in burying, and B is the number of red imported fire ants that did not participate in burying.

[0024] Figure 13 To show the proportion of red imported fire ants with different body sizes when burying 1-octadecene.

[0025] Figure 14 To show the proportion of red imported fire ants with different body sizes when burying Span 20.

[0026] Figure 15 For the burying behavior induced by the original solution of 1-octadecene.

[0027] Figure 16 For the burying behavior induced by the original solution of Span 20. Detailed implementation manners

[0028] Now, various exemplary implementation manners of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0029] It should be understood that the terms described in the present invention are only for describing specific implementation manners and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0030] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although this invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of this invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the said documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0031] Without departing from the scope or spirit of this invention, various modifications and variations can be made to the specific embodiments of the specification of this invention, which are obvious to those skilled in the art. Other embodiments obtained from the specification of this invention are obvious to those skilled in the art. The specification and examples of this application are merely exemplary.

[0032] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0033] The technical solutions described in this invention, unless otherwise specified, are all conventional solutions in the art, and the reagents or raw materials used, unless otherwise specified, are all purchased from commercial channels or have been made public.

[0034] The embodiments of this invention provide the application of Span 20 in repelling Solenopsis invicta.

[0035] The embodiments of this invention also provide the application of Span 20 as a Solenopsis invicta repellent or in the preparation of a Solenopsis invicta repellent.

[0036] The embodiments of this invention also provide a Solenopsis invicta repellent, comprising Span 20.

[0037] In some specific embodiments, the volume content of Span 20 is 8% - 100%.

[0038] The embodiments of this invention also provide a method for repelling Solenopsis invicta, using Span 20 or the said Solenopsis invicta repellent to repel Solenopsis invicta.

[0039] Example 1

[0040] 1 Test materials

[0041] 1.1 Test reagents and instruments

[0042] Ultra-pure water;

[0043] 1-Octadecene, CAS: 112 - 88 - 9; Span 20, CAS: 1338 - 39 - 2; n-Hexane, chromatographically pure. All were purchased from Shanghai Macklin Biochemical Co., Ltd.

[0044] Glass beakers coated with talcum powder (100 mL, 50 mL), square filter papers with a side length of 2.5 cm, wooden sticks, pipettes (1000 μL, 100 μL), 1 mL centrifuge tubes, medical absorbent cotton, paper cups with a bottom diameter of 52 mm, tweezers, knives, cabinet refrigerators (-20 °C), experimental record books, mobile phone cameras.

[0045] 1.2 Test insects

[0046] The red imported fire ants used in the experiment were collected from the back mountain of Yunnan Agricultural University. When collecting, dig out the central part of the ant nest with a spade, and then put the dug ant nest soil blocks into a plastic bucket (the inner wall of the bucket needs to be coated with talcum powder in advance to prevent the red imported fire ants from climbing out). After the ant colony is collected, let it stand for one week. Wait until the ant colony returns to calm and builds a new ant nest. Then put the plastic bucket containing the red imported fire ant nest into a water tank, and use the water drop method to slowly drip tap water into the soil. When the ant colony is forced out, use a strainer to fish out the red imported fire ants that are clustered into a ball and floating on the water surface, and then transfer them to a plastic storage box coated with talcum powder. Store the storage box in an environment with an indoor temperature of 24 °C - 26 °C and a humidity of 65% - 80%, and prepare artificial feeding with honey water and chopped ham sausage.

[0047] 2 Behavioral studies of red imported fire ants under two pheromone treatments

[0048] 2.1 Exploration of the repellent behavior of 1-octadecene and Span 20 on red imported fire ants

[0049] Dilute 1-octadecene by volume ratios of 3 times, 6 times, 9 times, and 12 times respectively for standby. Cut 1 g of ham sausage into evenly sized pieces and put them into a 50 mL beaker. Use a 100 μL pipette to respectively suck 30 μL of 1-octadecene with different concentrations and drop them into the beaker, and soak the cut ham sausage for 10 min. Select ants with the same body size from the same ant nest using the wooden stick method, and put them into a 100 mL beaker coated with talcum powder. Put the processed ham sausage on the lid of a 1 mL centrifuge tube, and then use tweezers to put it into the beaker containing red imported fire ants. Observe and record the number of red imported fire ants after 1 h, and calculate the repellent rate of 1-octadecene with different dilution multiples. Use the ham sausage without any treatment as the control group. Each group treats 30 ants and repeats 3 times. The treatment method of Span 20 is the same as that of 1-octadecene.

[0050] Repellent rate (%) = (C - T) / (C + T) * 100;

[0051] Among them, C is the number of red imported fire ants in the control group, and T is the number of red imported fire ants in the treatment group.

[0052] The results show that within 1 h, 1-octadecene and Span 20 have a significant repellent effect on red imported fire ants ( Figure 1 , Figure 2)(P < 0.001, df = 1, F = 156.060), and as the solution concentration decreased, the repellency rates of both to Solenopsis invicta also decreased ( Figure 3 and Figure 4 ).

[0053] At 1 h, the repellency rates of 1-octadecene and Span 20 stock solutions were 88% and 90% respectively. When diluted 3-fold, the repellency rates were 78% and 83% respectively. When diluted 6-fold, the repellency rates were 68% and 73% respectively. When diluted 9-fold, the repellency rates were 51% and 65% respectively. When diluted 12-fold, the repellency rates were 43% and 51% respectively.

[0054] 2.2 Exploration of the effects of 1-octadecene and Span 20 on the burying behavior of Solenopsis invicta

[0055] Dilute 1-octadecene 3-fold and 6-fold respectively for standby. Use a 100 μL pipette to aspirate 50 μL of 1-octadecene at different concentrations respectively, moisten a filter paper with a side length of 2.5 cm, place the treated filter paper 5 cm away from the ant nest entrance, and observe and record the behavior process of Solenopsis invicta worker ants discovering and burying the treated filter paper. Use filter papers moistened with water and n-hexane as the control group, place them horizontally near the Solenopsis invicta nest together with the treated filter papers, and repeat three times. The treatment method of Span 20 is the same as that of 1-octadecene.

[0056] Percentage of Solenopsis invicta with different body sizes (%) = number of small worker ants / (number of small worker ants + number of large worker ants);

[0057] Among them, small worker ants are Solenopsis invicta with a body length of 2.0 - 4.0 mm; large worker ants are Solenopsis invicta with a body length of 4.0 - 7.0 mm.

[0058] During the process of 1-octadecene and Span 20 burying Solenopsis invicta, soil particles were first transported to the edge of the paper (15 - 30 min). After the edge was covered with particles, the soil particles were then transported onto the paper and around the paper (60 - 120 min)( Figure 5 and Figure 6 ). And the behavior of Solenopsis invicta burying Span 20 was significantly higher than that of burying 1-octadecene. (P < 0.001, df = 1, F = 24.850).

[0059] When using the 1-octadecene stock solution, the burying behavior of Solenopsis invicta started at about 5 min and ended at about 120 min( Figure 7 and Figure 9 ). When diluted 3-fold and 6-fold, the burying behavior started at 10 - 15 min and ended at about 90 min( Figure 7 and Figure 9)。And within the same time period, the red imported fire ants preferentially perform burial behavior towards 1-octadecene at high concentrations; under different concentration treatments, the burial behavior of the red imported fire ants towards the high-concentration 1-octadecene treatment is significantly higher than that of the low-concentration treatment (P<0.001, df = 2, F = 13.396).

[0060] When it comes to the original solution of Span 20, the burial behavior of the red imported fire ants starts at around 5 minutes, and there are still red imported fire ants performing burial behavior at 120 minutes. Around 150 minutes, the burial behavior gradually stops( Figure 8 、 Figure 10 ). When diluted 3 times and 6 times, the burial behavior starts at around 10 - 15 minutes and ends at around 135 minutes( Figure 8 、 Figure 10 ). And within the same time period, the red imported fire ants preferentially perform burial behavior towards the high-concentration Span 20.

[0061] Under different dilution multiples of 1-octadecene and Span 20, the number of red imported fire ants participating in burial gradually increases over time, and the number of accumulated soil particles also gradually increases. Around 60 - 75 minutes, the number of red imported fire ants participating in burial gradually decreases, and the burial behavior also gradually stops( Figure 9 、 Figure 10 ). And the number of red imported fire ants participating in burying high-concentration 1-octadecene and Span 20 is significantly higher than the number of red imported fire ants participating in burying low-concentration 1-octadecene and Span 20.

[0062] (P<0.001, df = 2, F = 5.590).

[0063] During the occurrence of the burial behavior, only a small number of red imported fire ants participate in carrying soil particles, which is significantly less than the number of red imported fire ants not participating in carrying soil particles( Figure 11 、 Figure 12 )(P<0.001).

[0064] Most of the red imported fire ants participating in the burial behavior are small worker ants, which is significantly more than the large worker ants (P<0.001, df = 1, F = 17.794). When burying 1-octadecene, the number of small worker ants is about 200, and the number of large worker ants is about 25. During the burial process, the number of small worker ants accounts for about 89% of the total number of red imported fire ants participating in burial( Figure 13 ), when burying Span 20, the number of small worker ants is about 871, and the number of large worker ants is about 130. During the burial process, the number of small worker ants accounts for about 87% of the total number of red imported fire ants participating in burial( Figure 14 ).

[0065] 2.3 Exploration on the Influence of 1-octadecene and Span 20 on the Ant's Corpse-carrying Behavior

[0066] Cut a paper cup with a bottom diameter of 52 mm into a cylinder with a height of 1 cm for later use. Select ants of the same size from the same ant nest using the spring label method, put them into a 100 mL beaker coated with talcum powder, and then place them in a -20 °C refrigerator for 15 min to freeze and prepare for later use; use a 1000 μL pipette to aspirate 300 μL of 1-octadecene into the beaker, and put 5 g of frozen red imported fire ants into the beaker and soak for 24 h. Put the processed red imported fire ant corpses into the cut paper cup, and then use tweezers to place them near the red imported fire ant nest. Observe and record the behavior process of red imported fire ant workers burying the corpses of the ants. Use the red imported fire ant corpses that were frozen and placed for 24 h but not treated in any way as the control group, and conduct three replicates. The treatment method of Span 20 is the same as that of 1-octadecene.

[0067] Results of the behavior of red imported fire ant workers carrying the corpses of the treated ants( Figure 15 、 Figure 16 ) showed that only the corpses of red imported fire ants soaked in 1-octadecene and Span 20 had the phenomenon of workers burying the corpses, while the corpses of red imported fire ants that were not soaked were carried by the workers to the refuse pile. The burying behavior of red imported fire ant workers started around 15 min. As time went by, the number of red imported fire ants participating in burying the corpses gradually increased, and the number of accumulated soil particles gradually increased, and it basically ended at 90 min.

[0068] In summary, for the ham sausages soaked in 1-octadecene and Span 20 at different dilution multiples for 10 min, red imported fire ants showed repellency to them. After the foraging workers came into contact with the two pheromones, they would send signals to prevent other red imported fire ants from approaching the treated ham sausages, and the repellency rate decreased with the decrease of the pheromone concentration. That is, 1-octadecene and Span 20 would induce the repellency behavior of red imported fire ants, and the degree of repellency was related to the pheromone concentration. The greater the concentration, the stronger the repellency effect, and the lower the concentration, the weaker the repellency effect. In addition, red imported fire ants tended to stay away from the ham sausages treated with 1-octadecene and Span 20, but still actively fed on the ham sausages in the control group, which indicated that the use of the two pheromones affected the foraging behavior of red imported fire ants.

[0069] The filter paper soaked with 1-octadecene and Span 20 at different concentrations and the bodies of red fire ants soaked with them were buried by other red fire ants. The identification and burying behaviors of red fire ants were different at different concentrations. The burying behavior of red fire ants with high concentration of pheromones was earlier than that of pheromones with low concentration, and the burying behavior was more active. That is, the number of red fire ants involved in identifying and burying high-concentration pheromones was greater, and the burying time was longer. This shows that the use of the two pheromones affected the behavior of other red fire ants. In addition, during the burying behavior of red fire ants, only a small number of small red fire ants participated in carrying soil particles. These ants usually completed the burying task many times, which shows that there is a clear division of labor among red fire ants, and the burying behavior is carried out by worker ants of a specific group. The red fire ants buried the corpses of the red fire ants soaked in 1-octadecene and Siban-20, but carried the corpses that were not soaked to the corpse dump. These two completely different reactions indicate that the use of the two pheromones may have caused the corpses of the red fire ants to produce new pheromones, thereby changing the behavioral activities of the red fire ants.

[0070] Red fire ants are social animals, and the communication between ants is mediated by pheromones, so different pheromones have different effects on the behavior of red fire ants. Many researchers have previously focused on the repellent pheromones of red fire ants, but because most repellent pheromones are highly volatile, the repellent effect does not last long, and most of them have a pungent smell, so no repellent pheromones suitable for the prevention and control of red fire ants have been found. However, the filter paper and red fire ant corpses treated with the two pheromones 1-octadecene and Span 20 will cause red fire ants to have obvious repellent behavior, bury behavior, and bury corpses. After 24 hours, they will still interfere with the behavior of red fire ants, and the smell of the two is not irritating, which is a relatively ideal repellent pheromone. In addition, when the behavior of red fire ants is inhibited, they will move soil particles to bury the pheromones that inhibit their behavior, and the particles moved around or on the pheromones may act as a physical barrier to prevent the odor of pheromones from interfering with their behavior.

[0071] 1-Octadecene and Sban 20 are usually used as surfactants. The present invention finds that 1-Octadecene and Sban 20 at different dilution ratios can induce contact and recognition of red fire ants, thereby causing them to repel, bury and bury corpses, thereby achieving the purpose of regulating the behavior of red fire ants. 1-Octadecene and Sban 20 have a significant repellent effect on red fire ants. When their behavior is inhibited by pheromones, red fire ant workers will carry soil particles to bury pheromones. The functional excavation of the two pheromones, 1-Octadecene and Sban 20, and the study of the behavioral regulation effect can lay a foundation for the study of pheromone control of red fire ants and provide new ideas for the ecological regulation of red fire ants in real life.

[0072] Obviously, the above embodiments of the present invention are merely examples given to clearly illustrate the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. Application of Siban 20 in repelling red fire ants.

2. Use of Siban 20 as a red fire ant repellent or in the preparation of a red fire ant repellent.

3. A red fire ant repellent, characterized in that: Including Siban 20.

4. The red fire ant repellent according to claim 3, characterized in that: The volume content of Siban 20 is 8% to 100%.

5. A method for avoiding red fire ants, characterized in that: Use Siban 20 or the red fire ant repellent described in claim 3 to repel red fire ants.

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