A kind of bait for controlling black-winged termites

Abstract

This invention discloses a bait for controlling black-winged subterranean termites. The bait comprises a mixture of a lignocellulose bait matrix and an insecticidal active agent. The lignocellulose bait matrix is ​​formed by solid-state fermentation and degradation of lignocellulose substrate using white-rot fungi. The insecticidal active agent is selected from one of the following: bromutoxonil, flupyrrolidone, flonicamid, difenoconazole, and tetrazolium. The white-rot fungus is selected from one of the following: *Pterocarya stenoptera*, *Pterocarya stenoptera*, or *Pleurotus ostreatus*. The lignocellulose substrate is selected from one of the following: pine sawdust, sugarcane bagasse, corn cob, rice straw, or bamboo powder. This invention, by screening for the low-repellency, high-toxicity insecticidal active ingredient of bromutoxonil and combining it with the lignocellulose bait matrix degraded by solid-state fermentation of white-rot fungi, ensures the bait's palatability to black-winged subterranean termites and allows for effective diffusion of the agent through worker termite feeding behavior, achieving both environmental friendliness and colony eradication.

Description

Technical Field

[0001] This invention relates to the fields of agriculture, forestry and water technology, and in particular to a bait that can control black-winged subterranean termites. Background Technology

[0002] Black-winged subterranean termites are a type of subterranean termite widely distributed in areas south of the Yellow River in my country, seriously damaging agricultural and forestry crops, garden trees, and water conservancy projects. Termite damage is characterized by its insidious nature, widespread impact, and severity, especially causing major hazards such as seepage, piping, and even dam collapse in dikes. Currently, termite control methods mainly include dusting, pesticide application, and baiting. Among these, baiting has become an important termite control method due to its advantages such as lower pesticide dosage, less environmental impact, and effectiveness in eradicating the termite nest. Termite baits typically consist of a bait base and a slow-acting insecticidal active ingredient. Their mechanism of action involves termites ingesting the bait and then transmitting the pesticide to other individuals within the termite colony through cross-feeding behavior, thereby eradicating the termite nest.

[0003] However, existing termite baits still have some shortcomings. For example, some agents have repellent or antifeedant properties against termites, affecting their continued feeding; some agents, although possessing a certain degree of toxicity, have poor transmission effects and are difficult to effectively spread within the colony; in addition, the palatability of some baits is unstable under wild conditions, affecting the actual control effect. Therefore, screening for active ingredients with high toxicity, low repellency, effective transmission among worker termites, and good compatibility with bait substrate is of great significance for developing novel and highly effective black-winged subterranean termite baits. Therefore, this invention proposes a bait for controlling black-winged subterranean termites to solve the problems existing in the prior art. Summary of the Invention

[0004] To address the aforementioned problems, the present invention aims to provide a bait that can control black-winged subterranean termites. This bait, through screening for the low-repellency, high-toxicity insecticidal active ingredient of bromofenozide, is combined with a lignocellulose bait matrix degraded by solid-state fermentation of white-rot fungi. This ensures the bait's palatability to black-winged subterranean termites and allows for effective diffusion of the bait within the colony through worker termite feeding behavior. It effectively eradicates the entire termite colony while reducing the dosage and environmental risks, thus combining environmental friendliness with colony eradication.

[0005] To achieve the objective of this invention, the invention is implemented through the following technical solution: a bait for controlling black-winged subterranean termites, comprising a bait composed of a lignocellulose bait matrix and an insecticidal active agent. The bait matrix is ​​formed by solid-state fermentation and degradation of lignocellulose base material by white-rot fungi. The insecticidal active agent is one of bromfenac, flupyrrolidone, flonicamid, difenoconazole, and tetrazolium. The white-rot fungi are selected from one of *Pterocarya stenoptera*, *Pterocarya stenoptera*, or *Pleurotus ostreatus*. The lignocellulose base material is selected from one of pine sawdust, sugarcane bagasse, corn cob, rice straw, or bamboo powder.

[0006] A further improvement is that the insecticidal active agent has a mass percentage content of 0.0001% to 0.01% in the bait.

[0007] A further improvement is that the preparation of the lignocellulose bait matrix includes the following steps: S1. Base material pretreatment: Crush the lignocellulose base material through a 20-60 mesh sieve, adjust the moisture content to 60%-70%, transfer the crushed base material to a mixing tank, add bran or rice bran as a nitrogen source regulator in proportion, and adjust the carbon-nitrogen ratio to (15-30):1. S2. Solid-state fermentation: Inoculate the pretreated substrate with liquid or solid white rot fungi from wood chips. The inoculation amount is 10% to 15% of the dry weight of the substrate. Ferment and cultivate in the dark for 15 to 25 days at a temperature of 25 to 28°C and a relative humidity of 70% to 80% until the mycelium completely covers the surface of the substrate to obtain a bait for killing black-winged termites.

[0008] A further improvement is that the dry weight of the mycelium of the white rot fungus liquid strain in S2 is 5~15 g / L.

[0009] A further improvement is that the preparation of the insecticidal active agent includes the following steps: A1. Dissolving the active ingredient and preparing the mother liquor: Weigh 98% of the active ingredient by mass, add 2% by mass of analytical grade acetone as a co-solvent, and stir on a magnetic stirrer at a speed of 300-500 rpm for 15-20 minutes until the active ingredient crystals are completely dissolved and a clear and transparent mother liquor is formed. A2. Base material mixing and loading: The concentration of the working solution is uniformly diluted and stirred on the prepared base material at a mass fraction ratio of 0.0001%~0.01%. After mixing, it is dried at room temperature and ventilated for 12-24 hours, turning it over once every 2 hours to obtain a solid bait base material loaded with insecticidal active ingredients.

[0010] A further improvement is made in that the bait monitoring and trapping method includes the following steps: B1. Load the prepared bait into the carrier device; B2. Visually locate and identify signs of activity or affected areas of black-winged subterranean termites; B3. Place the carrier device near the identified signs of activity and regularly check or remotely monitor the termite feeding until the termite activity disappears.

[0011] A further improvement is that the carrier device in B1 includes a paper bait bucket and a monitor. The paper bait bucket is used to attract and collect termites, and the monitor is used to periodically photograph the feeding traces and mud coverage on the bait surface.

[0012] Further improvements are made in that the signs of activity in B2 include mud cover, mud lines, ant trails, swarming holes, and tree bases.

[0013] The beneficial effects of this invention are as follows: By screening the low-repellent and high-toxicity insecticidal active ingredients of bromfenac-methyl and combining them with the lignocellulose bait matrix degraded by solid-state fermentation of white-rot fungi, this invention not only ensures the palatability of the bait to black-winged subterranean termites, but also achieves effective diffusion of the agent within the colony by relying on the feeding behavior of worker ants. This reduces the amount of pesticide used and environmental risks while efficiently killing all termites in the colony, thus combining environmental friendliness with colony eradication. Attached Figure Description

[0014] Figure 1 This is a flowchart illustrating the preparation process of the lignocellulose bait matrix of the present invention. Figure 2 This is a flowchart illustrating the preparation process of the insecticidal active agent of the present invention; Figure 3 This is a flowchart of the bait monitoring and trapping method of the present invention; Figure 4 A bar chart showing the repellent effect of the bromoxynil dimethamide of the present invention on black-winged subterranean termites; Figure 5 Line graph showing the mortality rate of termites in the bromoxynil-fluorinated soil treatment group according to the present invention. Figure 6 Line graph showing the mortality rate of termites transmitting poison in the bromoxynil-fluorinated soil treatment group of the present invention. Figure 7 This is a bar chart showing the feeding rate of the bromoxynil dimethamide bait of the present invention; Figure 8 This is a line graph showing the mortality rate of poisoned termites in the bromoxynil dimethamide bait treatment group of the present invention. Figure 9 This is a line graph showing the mortality rate of termites transmitting the poison in the bromoxynil dimethicone bait treatment group of the present invention. Figure 10 A bar chart showing the feeding rate of 5 μg / g bromofenofibrate bait in the paper baiting bucket of the present invention; Figure 11This is a bar chart showing the feeding rate of 10 μg / g bromofenofibrate bait in the paper bait bucket of the present invention. Detailed Implementation

[0015] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0016] Example 1 according to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 As shown, this embodiment provides a bait that can control black-winged subterranean termites. The bait consists of a mixture of a lignocellulose bait matrix and an insecticidal active agent. The lignocellulose bait matrix is ​​made by solid-state fermentation and degradation of lignocellulose base material by white-rot fungi. The insecticidal active agent is bromfenacin, the white-rot fungi are selected from *Phellinus hemlock*, and the lignocellulose base material is selected from pine sawdust.

[0017] The insecticidal active agent in the bait contains 0.0005% by mass, and the mass ratio of the lignocellulose bait matrix degraded by white rot fungi is 99.9995%.

[0018] The preparation of lignocellulose bait matrix includes the following steps: S1. Base material pretreatment: Crush the lignocellulose base material through a 20-mesh sieve, adjust the moisture content to 60%, transfer the crushed base material to a mixing tank, add bran or rice bran as a nitrogen source regulator in proportion, and adjust the carbon-nitrogen ratio to 25:1. S2. Solid-state fermentation: Inoculate the pretreated substrate with liquid or solid white rot fungi from wood chips. The inoculation amount is 10% of the dry weight of the substrate. Ferment and cultivate in the dark for 15 days at a temperature of 25℃ and a relative humidity of 80% until the mycelium completely covers the surface of the substrate to obtain a bait for killing black-winged termites.

[0019] The dry weight of mycelium in the liquid culture of white rot fungi in S2 is 5~15 g / L.

[0020] The preparation of insecticidal active agents includes the following steps: A1. Dissolving the active ingredient and preparing the mother liquor: Weigh 98% of the active ingredient by mass, add 2% by mass of analytical grade acetone as a co-solvent, and stir on a magnetic stirrer at 300 rpm for 15 minutes until the active ingredient crystals are completely dissolved and a clear and transparent mother liquor is formed. A2. Base material mixing and loading: The concentration of the working solution is uniformly diluted and stirred on the prepared base material at a mass fraction ratio of 0.0005%. After mixing, it is dried at room temperature and ventilated for 12 hours, turning it over once every 2 hours to obtain a solid bait base material loaded with insecticidal active ingredients.

[0021] The baiting and trapping method includes the following steps: B1. Load the prepared bait into the carrier device; B2. Visually locate and identify signs of activity or affected areas of black-winged subterranean termites; B3. Place the carrier device near the identified signs of activity and regularly check or remotely monitor the termite feeding until the termite activity disappears.

[0022] The carrier device in B1 includes a paper bait bucket and a monitor. The paper bait bucket is used to attract and collect termites, and the monitor is used to periodically photograph the feeding traces and mud coverage on the bait surface.

[0023] Signs of activity in B2 include mud cover, mud lines, ant trails, swarming holes, and tree bases.

[0024] Example 2: according to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 , Figure 11 As shown, this embodiment provides a bait that can control black-winged subterranean termites. The bait consists of a mixture of a lignocellulose bait matrix and an insecticidal active agent. The lignocellulose bait matrix is ​​made by solid-state fermentation and degradation of lignocellulose base material by white-rot fungi. The insecticidal active agent is bromfenacin, the white-rot fungi are selected from *Pterygospermum jasminoides*, and the lignocellulose base material is selected from pine sawdust.

[0025] The insecticidal active agent in the bait contains 0.001% by mass, and the mass ratio of the lignocellulose bait matrix degraded by white-rot fungi is 99.999%.

[0026] The preparation of lignocellulose bait matrix includes the following steps: S1. Base material pretreatment: Crush the lignocellulose base material through a 50-mesh sieve, adjust the moisture content to 70%, transfer the crushed base material to a mixing tank, add bran or rice bran as a nitrogen source regulator in proportion, and adjust the carbon-nitrogen ratio to 30:1. S2. Solid-state fermentation: Inoculate the pretreated substrate with liquid or solid white rot fungi from wood chips. The inoculation amount is 15% of the dry weight of the substrate. Ferment and cultivate in the dark for 25 days at a temperature of 28℃ and a relative humidity of 70% until the mycelium completely covers the surface of the substrate to obtain a bait for killing black-winged termites.

[0027] The dry weight of mycelium in the liquid culture of white rot fungi in S2 is 5 g / L.

[0028] The preparation of insecticidal active agents includes the following steps: A1. Dissolving the active ingredient and preparing the mother liquor: Weigh 98% of the active ingredient by mass, add 2% by mass of analytical grade acetone as a co-solvent, and stir on a magnetic stirrer at 300 rpm for 15 minutes until the active ingredient crystals are completely dissolved and a clear and transparent mother liquor is formed. A2. Base material mixing and loading: The concentration of the working solution is uniformly diluted and stirred on the prepared base material at a mass fraction ratio of 0.0001%. After mixing, it is dried at room temperature and ventilated for 20 hours, turning it over once every 2 hours during the period to obtain a solid bait base material loaded with insecticidal active ingredients.

[0029] The baiting and trapping method includes the following steps: B1. Load the prepared bait into the carrier device; B2. Visually locate and identify signs of activity or affected areas of black-winged subterranean termites; B3. Place the carrier device near the identified signs of activity and regularly check or remotely monitor the termite feeding until the termite activity disappears.

[0030] The carrier device in B1 includes a paper bait bucket and a monitor. The paper bait bucket is used to attract and collect termites, and the monitor is used to periodically photograph the feeding traces and mud coverage on the bait surface.

[0031] Signs of activity in B2 include mud cover, mud lines, ant trails, swarming holes, and tree bases.

[0032] Using lignocellulose bait degraded by white-rot fungi as the base material and bromonantrol as the main insecticidal active ingredient, a bait suitable for feeding on black-winged subterranean termites was prepared. To screen suitable active ingredients, indoor toxicity comparisons, repellency tests, and toxin transfer tests were conducted on bromonantrol, flupyrrolidone, flonicamid, difenoconazole, and tetrazolium. The results are shown in Table 1. In the repellency test at 100 μg / g, there was no significant difference in the number of worker termites between the bromonantrol treatment area and the control area at 2h, 4h, and 6h, indicating that bromonantrol had no significant repellent effect on termites. The toxin transfer test results showed that under toxic soil treatment conditions, after 5 days of treatment with 5 μg / g and 10 μg / g bromonantrol, the mortality rates of poisoned worker termites were 51.67% and 58.33%, respectively, significantly higher than the control group. The results are shown in Table 2.

[0033] Table 1. Indoor poisoning effects of five pesticides on black-winged subterranean termites. Table 2. Indoor toxicity of five pesticides against black-winged subterranean termites. Experimental Example 1 Indoor poisoning tests were conducted on the baits obtained in Examples 1 and 2. Fifty healthy, highly active black-winged subterranean termite worker ants of uniform size were placed in a 28 cm × 18.5 cm plastic box. 3 g of the tested bait was added to each box, with 3 g of untreated bait serving as a control. The boxes were placed in the dark at room temperature for the termites to feed on. The number of termite deaths was recorded every 24 hours for 96 consecutive hours. After treatment with 5 μg / g bromofenac sodium bait for 24 h, 48 h, 72 h, and 96 h, the worker ant mortality rates were 24.00%, 38.67%, 60.00%, and 80.67%, respectively. After treatment with 10 μg / g bromofenac sodium bait for 24 h, 48 h, 72 h, and 96 h, the worker ant mortality rates were 36.67%, 59.33%, 73.33%, and 86.67%, respectively. The results showed that the bait of the present invention had a significant toxic effect on black-winged subterranean termites. The mortality rate of the 10 μg / g treatment was higher than that of the 5 μg / g treatment at 48 h and 72 h, and the mortality rate of both treatment groups reached more than 80% after 96 h.

[0034] Table 3. Indoor poisoning effect of bromoxynil dimethamide bait on black-winged subterranean termite workers. Note: The table shows mean ± standard deviation. Different letters indicate significant differences. P <0.05) Experimental Example 2 The baits prepared in Examples 1 and 2 were stained with 0.1% neutral red dye. Fifty healthy black-winged subterranean termite worker ants were placed in a 28 cm × 18.5 cm plastic box. The stained bait was placed in the center of the box, and the termites were allowed to feed under dark conditions at room temperature. Five worker ants whose intestines were successfully stained were selected as vectors, and 15 unstained worker ants were selected as recipients. The vector and recipient worker ants were transferred together to a plastic box lined with soil. Each treatment was repeated three times, and the number of deceased recipient worker ants was recorded every 24 hours. After 5 days of treatment, the mortality rate of poisoned worker ants in the 5 μg / g bromfenac bait group was 51.11%, and the mortality rate in the 10 μg / g bromfenac bait group was 66.67%, both significantly higher than the control group (13.33%), and the 10 μg / g treatment group had a higher mortality rate than the 5 μg / g treatment group. The mortality rates of the termites in both the 5 μg / g and 10 μg / g treatment groups reached 100%, significantly higher than the control group. This demonstrates that 5 μg / g and 10 μg / g bromfenac in the bait can effectively transfer the poison among worker ants of the black-winged subterranean termite.

[0035] Experimental Example 3 The baits obtained in Examples 1 and 2 were placed into paper bait containers and placed near the base of garden trees, mud lines, or termite tunnels where black-winged subterranean termites were active. A control without bait was set up. After the experiment, the remaining bait and its surface mud were removed, and the termites' feeding was observed and the consumption rate was calculated. Under the treatment condition of 5 μg / g bromofenofibrate bait, varying degrees of feeding traces and mud coverage were observed on the surface of the bait in the bait containers at different monitoring points, with some monitoring points showing complete consumption of the bait. Under the treatment condition of 10 μg / g bromofenofibrate bait, significant consumption of the bait was also observed in the bait containers, with most or even all of the bait in some monitoring points being consumed, and the surface covered with mud. This demonstrates that the bait of the present invention can attract black-winged subterranean termites to feed under field conditions. Further testing of the predation rate showed that the average predation rate of the 5 μg / g bromufenproxil fumarate bait was 61.90%, compared to 42.22% in the control group without the bait, with no significant difference between the two. Similarly, the average predation rate of the 10 μg / g bromufenproxil fumarate bait was 63.13%, compared to 72.71% in the control group without the bait, also with no significant difference between the two. These results indicate that, under field conditions, the 5 μg / g and 10 μg / g bromufenproxil fumarate baits were effective in attracting and controlling black-winged subterranean termites. After 75 days of application of the 5 μg / g and 10 μg / g bromufenproxil fumarate baits in paper bait containers, Table 4 shows that the termite climbing rate decreased by 66.67%. Therefore, the 5 μg / g and 10 μg / g bromufenproxil fumarate baits have a good control effect on black-winged subterranean termites in gardens.

[0036] Table 4. Effects of bromoxynil dimethoate bait in paper bait barrels on the tree-climbing activity of black-winged subterranean termites. Note: 1. If termite activity is still present on the tree surface, but no new mud or mud lines are found, and the existing mud or mud lines have become dry, hard, and broken, then the termite activity at this application point is considered reduced. If termite activity is still present, and the existing mud or mud lines remain moist and intact, without becoming dry, hard, or broken, and obvious repair marks are visible, then the termite activity at this application point is considered normal. 2. Termite infestation rate (%) = Number of trees infested with termites × 100 / Total number of trees where bromoxynil dimethyl methacrylate bait was applied. The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A bait agent for controlling black-winged subterranean termites, characterized in that: The product includes a baiting agent, which is a mixture of a lignocellulose bait matrix and an insecticidal active agent. The lignocellulose bait matrix is ​​formed by solid-state fermentation and degradation of a lignocellulose base material by white-rot fungi. The insecticidal active agent is one of bromfenac, flupyrrolidone, flonicamid, difenoconazole, and tetrazolium. The white-rot fungi are selected from one of *Pterocarpus sanguinalis*, *Pterocarpus spp.*, or *Pleurotus ostreatus*. The lignocellulose base material is selected from one of pine sawdust, sugarcane bagasse, corn cob, rice straw, or bamboo powder.

2. The bait agent for controlling black-winged subterranean termites according to claim 1, characterized in that: The insecticidal active agent has a mass percentage content of 0.0001% to 0.01% in the bait.

3. The bait agent for controlling black-winged subterranean termites according to claim 1, characterized in that: The preparation of the lignocellulose bait matrix includes the following steps: S1. Base material pretreatment: Crush the lignocellulose base material through a 20-60 mesh sieve, adjust the moisture content to 60%-70%, transfer the crushed base material to a mixing tank, add bran or rice bran as a nitrogen source regulator in proportion, and adjust the carbon-nitrogen ratio to (15-30):

1. S2. Solid-state fermentation: Inoculate the pretreated substrate with liquid or solid white rot fungi from wood chips. The inoculation amount is 10% to 15% of the dry weight of the substrate. Ferment and cultivate in the dark for 15 to 25 days at a temperature of 25 to 28°C and a relative humidity of 70% to 80% until the mycelium completely covers the surface of the substrate to obtain a bait for killing black-winged termites.

4. The bait agent for controlling black-winged subterranean termites according to claim 3, characterized in that: The dry weight of the mycelium of the white-rot fungus liquid strain in S2 is 5~15 g / L.

5. The bait agent for controlling black-winged subterranean termites according to claim 1, characterized in that: The preparation of the insecticidal active agent includes the following steps: A1. Dissolving the active ingredient and preparing the mother liquor: Weigh 98% of the active ingredient by mass, add 2% by mass of analytical grade acetone as a co-solvent, and stir on a magnetic stirrer at a speed of 300-500 rpm for 15-20 minutes until the active ingredient crystals are completely dissolved and a clear and transparent mother liquor is formed. A2. Base material mixing and loading: The concentration of the working solution is uniformly diluted and stirred on the prepared base material at a mass fraction ratio of 0.0001%~0.01%. After mixing, it is dried at room temperature and ventilated for 12-24 hours, turning it over once every 2 hours to obtain a solid bait base material loaded with insecticidal active ingredients.

6. The bait agent for controlling black-winged subterranean termites according to claim 1, characterized in that: The bait monitoring and trapping method includes the following steps: B1. Load the prepared bait into the carrier device; B2. Visually locate and identify signs of activity or affected areas of black-winged subterranean termites; B3. Place the carrier device near the identified signs of activity and regularly check or remotely monitor the termite feeding until the termite activity disappears.

7. The bait agent for controlling black-winged subterranean termites according to claim 6, characterized in that: The carrier device in B1 includes a paper bait bucket and a monitor. The paper bait bucket is used to attract and collect termites, and the monitor is used to periodically photograph the feeding traces and mud coverage on the bait surface.

8. The bait agent for controlling black-winged subterranean termites according to claim 6, characterized in that: The signs of activity in B2 include mud cover, mud lines, ant trails, swarming holes, and tree bases.

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