Plant essential oil for preventing and controlling stored product pests and application thereof

Abstract

The present invention provides plant essential oils for controlling stored product pests and their uses. The plant essential oils, dill oil and / or chelonia oil, have excellent fumigation, contact, and repellent activity against red flour beetles. The dill oil and chelonia oil provided by the present invention exhibit significant efficacy in controlling stored product pests, effectively inhibiting the occurrence and infestation of stored product pests.

Description

Technical Field

[0001] The invention belongs to the field of plant protection, and in particular relates to a plant essential oil for preventing and controlling stored product pests and an application thereof. Background Art

[0002] my country boasts abundant plant resources. Effectively developing and refining these resources into meaningful botanical pesticides not only enhances their inherent application value but also enables the creation of novel biopesticides to replace chemical pesticides, contributing to the sustainable development of green agriculture. Combining the volatility of essential oils with these new green biopesticides for controlling stored-grain pests, sanitary pests, food pests, and other stored-food pests offers significant potential, effectively driving a major shift in green pest control in my country's storage projects.

[0003] The red flour beetle, Tribolium castaneum (Herbst), is an economically important stored-food pest of the family Herbaceae in the order Coleoptera. It occurs and causes damage in most parts of my country. Adult red flour beetles secrete quinones, a highly unpleasant, yellowish-brown liquid, through glands on their thorax and abdomen. These substances seriously contaminate grain crops and other products, causing them to turn yellow and smelly, and even to clump and mold, reducing their quality and value, resulting in immeasurable economic losses. Quinones are also carcinogens that harm human health, and accidentally consuming food containing them can cause significant harm. Furthermore, red flour beetles serve as intermediate hosts for the tapeworm Pseudocercocephalus cruzi. Accidentally ingesting contaminated grain can lead to infection, resulting in symptoms such as diarrhea and vomiting. Plant essential oils are recognized as a new, environmentally friendly insecticide because they are less likely to induce insecticide resistance and are environmentally friendly. Summary of the Invention

[0004] In order to solve the problem of long-term use of chemical fumigants to control stored product pests, which is not conducive to the green development of storage projects, the present invention develops a low-toxic, safe and highly effective botanical insecticide.

[0005] The specific technical solutions are as follows:

[0006] The plant essential oil provided by the present invention can be used for preventing and controlling stored product pests. The plant essential oil is dill oil and / or terrapin oil; and the stored product pest is red flour beetle.

[0007] The plant essential oil has excellent fumigation activity, contact activity and repellent activity against red flour beetle.

[0008] The plant essential oil provided by the present invention is combined with an adjuvant to prepare a pesticide preparation, which is an emulsifiable concentrate, a microemulsion, or an aqueous emulsion.

[0009] Beneficial effects

[0010] The present invention provides dill oil and turmeric leaf oil, which have a significant effect on preventing and controlling stored product pests and can effectively inhibit the occurrence and damage of stored product pests. DETAILED DESCRIPTION

[0011] The present invention will be further described below with reference to specific embodiments.

[0012] Example 1:

[0013] Fumigation Effects of Dill Oil and Herba Glechomae Oil on Tribolium castaneum

[0014] 1. Test insects:

[0015] Red flour beetles were collected from farmers' granaries and artificially subcultured in the insectary of the College of Plant Protection, Anhui Agricultural University. Artificial rearing conditions were as follows: temperature (27 ± 1)°C, relative humidity (70 ± 5)%, light intensity (L:D) = 0 h:24 h. The artificial diet consisted of wheat ground in a crusher and yeast powder mixed in a mass ratio of 10:1. The wheat was cleaned and dried in an oven at 80°C for at least 2 h, ensuring a moisture content of (13 ± 1)%. After drying, the wheat was crushed using a clean crusher to produce a mixture of coarse and fine particles. A certain proportion of yeast powder was then added, shaken, and aliquoted into 300 mL glass bottles to the 1 / 3 mark. Approximately 80 to 100 adult red flour beetles were then inoculated and reared in the insectary under the aforementioned temperature, humidity, and light intensity conditions for 7 days. Adults were then screened out. About 5 to 7 days after a large number of adults are observed in the glass bottle, the above operation is repeated until three generations of artificially reared red flour beetle adults are completed, and then adults with high vitality and consistent size and shape are selected for testing.

[0016] 2. Test reagents:

[0017] Dill oil and turtle grass oil (both purchased from Jiangxi Hualong Plant Spice Co., Ltd.) are pure natural plant essential oils.

[0018] 3. Experimental methods:

[0019] Using a micropipette, dill oil and turmeric oil were pipetted at varying concentrations to create solutions. A closed-flask fumigation method was used to test the fumigation effect of red flour beetles. The procedure was as follows: To prevent red flour beetles from climbing onto the flask opening, a layer of polytetrafluoroethylene (PTFE dispersion) was applied to the inner wall of a 250 mL flask before the experiment began. After drying, 30 adult red flour beetles of uniform size were placed into the flask. A 10 cm filter paper strip was cut into 5 cm long and 1 cm wide strips. These were threaded with cotton thread and hung approximately 5 cm from the bottom of the flask, ensuring they did not come into contact with the inner wall. A micropipette was used to dispense a dose of the test plant essential oil onto the lower end of the filter paper strip. The flask opening was quickly sealed with sealing film and transparent tape. Finally, the triangular flask was placed in a completely dark light incubator at a temperature of (27±1)°C and a relative humidity of (70±5). The activity of the test insects was observed at 12h, 24h, 36h, 48h, 60h and 72h, and then the bottle mouth was opened to allow the air to dissipate for 24h, and the death of the red flour beetle was recorded. The blank control group was set as the control group without adding essential oil, and each essential oil treatment group and the blank control group were repeated 3 times. The mortality rate and the corrected mortality rate were calculated using the following formula:

[0020]

[0021]

[0022] 4. Results and Analysis

[0023] A pilot study designed five concentration gradients of the two essential oils to determine the dose-effect of their fumigation toxicity on Tribolium castaneum. Observations were also made at each concentration, with three replicates for each treatment, to determine the time-dependent toxicity of the two essential oils to Tribolium castaneum. The results are shown in Table 1. In the control group, no insects died within 72 hours, resulting in a corrected mortality rate of 0%. Table 1 shows that the corrected mortality rates of Tribolium castaneum increased with increasing fumigation concentrations at 12, 24, 36, 48, 60, and 72 hours of treatment with dill oil and chelonia oil. Furthermore, at the same concentration, dill oil and chelonia oil, respectively, increased with increasing fumigation duration. Among them, after 72 hours of dill oil treatment, the corrected mortality rates of red flour beetle caused by fumigation concentrations of 2μL / L, 4μL / L, 6μL / L, 8μL / L and 10μL / L were 15.55%, 38.89%, 47.78%, 55.55% and 77.78% respectively; after 72 hours of chelonia oil treatment, the corrected mortality rates of red flour beetle caused by fumigation concentrations of 4μL / L, 8μL / L, 12μL / L, 16μL / L and 20μL / L were 24.45%, 42.22%, 62.22%, 74.45% and 90.00% respectively, indicating that the fumigation effects of dill oil and chelonia oil on red flour beetle at different treatment concentrations at the same time have a certain dose effect. When treated with dill oil at a concentration of 10 μL / L, the adjusted mortality rates against Tribolium castaneum were 21.11%, 33.33%, 37.78%, 54.45%, 63.33%, and 77.78% at 12, 24, 36, 48, 60, and 72 hours, respectively. This indicates that dill oil has a time-dependent fumigation effect on Tribolium castaneum at the same concentration but different treatment times, providing a theoretical basis for the development of new botanical insecticides. To further illustrate the fumigation effects of dill oil and kelp oil on Tribolium castaneum, toxicity regression analysis was performed.

[0024] According to the fumigation results of dill oil and turmeric leaf oil on red flour beetle in Table 1, the logarithm of fumigation concentration and the corrected mortality value were fitted to obtain the toxicity regression equation, the median lethal concentration (LC) and the fumigation effect of dill oil and turmeric leaf oil on red flour beetle at different treatment times. 50 ) and correlation coefficient r, etc., the results are shown in Table 2. As shown in Table 2, when dill oil was fumigated to Tribolium castaneum for 12h, 24h, 36h, 48h, 60h and 72h, its LC 50 They were 14.00μL / L, 11.98μL / L, 10.58μL / L, 8.57μL / L, 7.00μL / L and 5.76μL / L respectively; among them, the LC of Tribolium castaneum after 12h of dill oil fumigation treatment was 50It is more than twice as long as 72 hours.

[0025] The LC values ​​of Tribolium castaneum oil on Tribolium castaneum were 12h, 24h, 36h, 48h, 60h and 72h respectively. 50 The LC values ​​of Tribolium castaneum after fumigation with turmeric leaf oil for 12 hours were 20.71μL / L, 16.58μL / L, 13.61μL / L, 11.57μL / L, 10.29μL / L and 8.38μL / L respectively. 50 The results showed that as the fumigation time increased, the LC of dill oil and turmeric oil on red flour beetle 50 It shows a gradually decreasing trend. As can be seen from Table 2, the correlation coefficients r in the regression equations of the toxicity of dill oil and turmeric leaf oil to red flour beetle are both above 0.90, indicating that the regression equations of the toxicity of the two plant essential oils to red flour beetle have a good fitting degree, which is consistent with the actual situation. At the same time, the LC 50 The fumigation toxicity of dill oil to red flour beetle is stronger than that of turmeric oil.

[0026] Table 1 Fumigation effects of dill oil and turmeric oil on Tribolium castaneum (mean ± standard error)

[0027]

[0028] Table 2 Regression analysis of the fumigation toxicity of dill oil and turmeric oil to Tribolium castaneum

[0029]

[0030] Note: Data in the table are means ± standard errors. Different letters in the same column indicate significant differences at the P < 0.05 level using Tukey's new multiple range test for the same concentration of essential oils under different treatments. Same below.

[0031] Example 2:

[0032] Contact toxicity of dill oil and turmeric oil against red flour beetle

[0033] 1. Test insects:

[0034] Same as Example 1.

[0035] 2. Test reagents:

[0036] Same as Example 1.

[0037] Acetone (analytical grade) was purchased from Shanghai Zhenqi Chemical Co., Ltd.

[0038] 3. Experimental methods:

[0039] The contact toxicity test was conducted using the filter paper coating method. To prevent red flour beetles from climbing onto the edges of the Petri dishes, a layer of polytetrafluoroethylene (PTFE dispersion) was applied to the inner walls of a 9 cm Petri dish before the test began. After drying, 30 adult red flour beetles of uniform size were placed on filter paper containing different concentrations of essential oil in 9 cm Petri dishes. Preliminary tests were conducted with decreasing concentrations of 50%, 30%, 10%, 5%, and 2%. Based on the contact mortality results of the preliminary tests, five appropriate contact toxicity concentrations were set for the final test. The procedure was as follows: 1 mL of each essential oil diluted in acetone was evenly applied to a 9 cm diameter filter paper from the outside inward. After 1 minute, the paper was glued to the bottom of the Petri dish using glue. The 30 adult red flour beetles were then evenly placed on the filter paper and the dish lid was closed. Place the Petri dishes in a dark, light-incubator at (27±1)°C and (70±5)% relative humidity. Observe the activity of the test insects at 12, 24, 36, 48, 60, and 72 hours of treatment. Record the number of dead insects and calculate the mortality rate and corrected mortality rate. Acetone treatment served as the control group. Repeat three times for each essential oil treatment group and the control group.

[0040] 4. Results and Analysis

[0041] Using the FAO-recommended filter paper film method, a pilot study designed five concentration gradients of two plant essential oils to determine their contact toxicity against red flour beetles (Triticum castaneum). The dose-response effect and time-dependent contact toxicity of the oils were determined at the same concentration for 12, 24, 36, 48, 60, and 72 hours. The contact toxicity test results are shown in Table 3. In the control group, no insects died within 72 hours, resulting in a corrected mortality rate of 0%. Table 3 shows that both dill oil and kelp oil exhibited strong contact toxicity against red flour beetles at certain concentrations. At the same treatment concentrations of 12, 24, 36, 48, 60, and 72 hours, the corrected mortality rates gradually increased with increasing contact concentration. At the same concentration, dill oil and kelp oil exhibited increasing contact toxicity against red flour beetles over time. After 72 hours of dill oil treatment, the corrected mortality rate of red flour beetles at 0.177 μL / cm 2 , 0.354μL / cm 2 , 0.531μL / cm 2 , 0.708μL / cm 2 and 0.885 μL / cm 2 The corrected mortality rates of Tribolium castaneum at the contact concentrations of 0.885 μL / cm 2 , 1.327μL / cm2 , 1.769μL / cm 2 , 2.212μL / cm 2 and 2.654 μL / cm 2 The corrected mortality rates at the contact killing concentrations of 0.885 μL / cm were 53.33%, 77.78%, 91.11%, 100.00% and 100.00%, respectively, indicating that at different treatment concentrations at the same time, the contact killing effects of dill oil and turmeric oil on red flour beetle had a certain dose effect. 2 The corrected mortality rates of red flour beetle at 12h, 24h, 36h, 48h, 60h and 72h were 24.33%, 56.67%, 71.11%, 82.22%, 92.22% and 100.00% respectively; the contact toxicity of turmeric leaf oil at the concentration of 2.654μL / cm 2 The corrected mortality rates of red flour beetle at 12h, 24h, 36h, 48h, 60h and 72h of treatment were 22.22%, 45.56%, 73.33%, 87.78%, 100.00% and 100.00%, respectively, indicating that at the same concentration but different treatment times, dill oil and turtle leaf oil have a certain time effect in their contact killing effect on red flour beetle.

[0042] Table 3 Contact toxicity of dill oil and turmeric oil to red flour beetle (mean ± standard error)

[0043]

[0044] Example 3:

[0045] Repellent effects of dill oil and turmeric oil on red flour beetle

[0046] 1. Test insects:

[0047] Same as Example 1.

[0048] 2. Test reagents:

[0049] Same as Example 1.

[0050] Acetone (analytical grade) was purchased from Shanghai Zhenqi Chemical Co., Ltd.

[0051] 3. Experimental methods:

[0052] The filter paper film method was used to conduct the repellent test. In order to prevent the red flour beetle test insects from climbing up the edge of the culture dish, before the start of the experiment, a layer of polytetrafluoroethylene (PTFE dispersion) was first applied on the inner wall of the 9cm culture dish and left to dry before use. Dill essential oil and turtle grass essential oil were diluted with acetone to different essential oil concentrations of 5μL / mL, 1μL / mL, 0.2μL / mL, 0.04μL / mL and 0.008μL / mL and placed in a 50mL centrifuge tube for use. Then select a filter paper with a diameter of 9cm and cut it in half into two semicircles. Apply 500μL of the above-mentioned essential oils of different concentrations on one half. The concentrations at this time are: 78.63nL / cm 2 、15.73nL / cm 2 、3.15nL / cm 2 , 0.63nL / cm 2 and 0.13 nL / cm 2 , and the other half is smeared with 500μL of acetone solvent as the control side. After the acetone evaporates, stick the two and a half filter paper pieces to the bottom of a culture dish with a diameter of 9cm (make sure there is a little distance between the centers of the two filter paper pieces to prevent the essential oil treatment side from spreading to the control side). Finally, place 30 red flour beetles in the center of the culture dish and cover it with a lid. Then place the culture dish in a completely dark incubator with a temperature of (27±1)℃ and a relative humidity of (70±5)% for repellent treatment for 12h, 24h, 36h, 48h, 60h and 72h. Check the repellency of the test. Repeat 3 times for each essential oil treatment group and control group. Calculate the repellency rate (PR). The specific calculation formula is as follows:

[0053]

[0054] The grading standards for repellency are:

[0055] Level 0: repellency rate is 0%; Level I: repellency rate is 0.1% to 20%;

[0056] Level II: repellency rate is 20.1% to 40%; Level III: repellency rate is 40.1% to 60%;

[0057] Level IV: repellency rate is 60.1% to 80%; Level V: repellency rate is 80.1% to 100%.

[0058] 4. Results and Analysis

[0059] The repellent activity of dill oil and turmeric leaf oil against red flour beetle was determined. The repellent results of the two plant essential oils against red flour beetle at different treatment times and concentrations are shown in Table 4. As can be seen from Table 4, dill oil and turmeric leaf oil had a low repellent effect at a concentration of 0.13 nL / cm 2Under the treatment of 12h, 24h, 36h and 48h, the dill oil showed a repellent effect on the red flour beetle; however, at 60h, the dill oil showed a repellent effect on the red flour beetle, and at 72h, it showed an attracting effect. The turtle grass showed an attracting effect at 60h and 72h. At the same time, the repellent effect of the two plant essential oils on the red flour beetle gradually increased with the increase of treatment concentration. At the maximum treatment concentration of 78.63nL / cm 2 Under the same repellent concentration, the repellent effect of dill oil on red flour beetle remained at level V as time went on, while the repellent level of turkey leaf oil remained above level IV, indicating that the repellent effects of the two plant essential oils were relatively stable. At 72 hours, the repellent rates of dill oil and turkey leaf oil on red flour beetle were 93.92% and 67.42%, respectively, with repellent levels of V and IV, respectively. At the same repellent concentration, the repellent effect of the two plant essential oils on red flour beetle showed a downward trend as time went on; among them, at the repellent concentration of 78.63nL / cm 2 Under the condition of 72h treatment, the repellency rate of dill oil and turmeric leaf oil against red flour beetle decreased by 6.08% and 32.58% respectively compared with that after 12h treatment. From the above data, it can be seen that dill oil and turmeric leaf oil have good repellent activity against red flour beetle within a certain time and concentration.

[0060] Table 4 Repellent effects of dill oil and turmeric oil on Tribolium castaneum (mean ± standard error)

[0061]

[0062] Example 4:

[0063] Effects of dill oil and turmeric leaf oil on controlling red flour beetle in simulated warehouse

[0064] 1. Test insects:

[0065] Same as Example 1.

[0066] 2. Test reagents:

[0067] Same as Example 1.

[0068] 3. Experimental methods:

[0069] Refer to Liu Guojun's simulated real warehouse test and make targeted improvements. The specific test operation steps are as follows:

[0070] (1) 18L plastic barrels were selected as wheat simulation bins for real warehouse simulation, and 10kg of wheat was added to each simulation bin (the height of wheat in the barrel was about 30cm);

[0071] (2) Use a hole puncher to evenly punch about 200 holes around the perimeter of a 50 mL centrifuge tube. The hole size should be large enough to prevent the adult red flour beetle from crawling out.

[0072] (3) Add coarsely ground wheat to the centrifuge tube to 1 / 3 of the tube and place 50 adult red flour beetles in the tube;

[0073] (4) Place the centrifuge tubes containing red castanea into the upper, middle, and lower layers of the simulation chamber;

[0074] (5) Use cotton thread to pass through the four corners of the filter paper to make it umbrella-shaped, and then add 3g of perlite to absorb the essential oil to ensure that the essential oil can be slowly released;

[0075] (6) The essential oils were tested at doses of 10, 20, 30, 40, and 50 times the maximum treatment concentration used when fumigating Tribolium castaneum for 72 h, and a blank control without any essential oil or reagent was set up;

[0076] (7) Filter paper loaded with essential oil at different concentrations was hung above the wheat in the simulated bin. The bin was covered and sealed with vaseline. The number of test insect deaths was observed 1, 7, 14, 21, and 28 days after the closed fumigation. Each treatment was repeated three times.

[0077] 4. Results and Analysis

[0078] In a simulated wheat warehouse, dill oil was treated at concentrations of 0.1 mL / L, 0.2 mL / L, 0.3 mL / L, 0.4 mL / L, and 0.5 mL / L, and chelonia ovata oil was treated at concentrations of 0.2 mL / L, 0.4 mL / L, 0.6 mL / L, 0.8 mL / L, and 1.0 mL / L. The warehouses were sealed and fumigated for 28 days in total darkness at a temperature of (27 ± 1)°C and a relative humidity of (75 ± 5)%. Observations were made on the first day and every seven days. The fumigation efficacy of the two plant essential oils in the simulated warehouse is shown in Tables 5 and 6. As can be seen from the tables, at the same fumigation concentration, the fumigation efficacy of dill oil and chelonia ovata oil against Tribolium castaneum in the upper, middle, and lower layers of the simulated warehouse varied significantly, and the differences in efficacy between the upper, middle, and lower layers increased with prolonged fumigation time. At the same fumigation time, there were certain differences in the fumigation and toxicity of dill oil and turmeric leaf oil against Tribolium castaneum in the upper, middle, and lower layers of the simulated wheat warehouse. These differences gradually increased with increasing fumigation concentrations. Seven days after fumigation, the corrected mortality rates of Tribolium castaneum in the upper layer of the simulated wheat warehouse reached 100% when treated with dill oil at a fumigation concentration of 0.5 mL / L and with turmeric leaf oil at a fumigation concentration of 0.8 mL / L. However, the corrected mortality rates in the middle and lower layers were not as high, with dill oil causing 32.67% and 4.00% and turmeric leaf oil causing 65.33% and 12.67%, respectively. This suggests that the closer the two plant essential oils are to the Tribolium castaneum, the better their fumigation and toxicity. When the fumigation concentration was 0.2 mL / L, the toxicity of dill oil was higher than that of turkey grass oil after 1 day of fumigation, but the toxicity was higher than that of dill oil after 7 days, 14 days, 21 days and 28 days of fumigation; when the fumigation concentration was 0.4 mL / L, the toxicity of dill oil was lower than that of turkey grass oil as a whole after 1 day, 7 days and 14 days of fumigation, but the toxicity was higher than that of dill oil after 21 days and 28 days of fumigation. This shows that in a real warehouse, the fumigation toxicity of turkey grass oil is better than that of dill oil under high concentration conditions for a short time.

[0079] To further illustrate the fumigation toxicity of dill oil and turmeric leaf oil on red flour beetle by simulated real warehouse fumigation, the fumigation treatment concentrations and corrected mortality values ​​in Tables 5 and 6 were subjected to toxicity regression analysis to obtain the toxicity regression equation of dill oil and turmeric leaf oil on red flour beetle by simulated real warehouse fumigation, the median lethal concentration (LC 50 ) and correlation coefficient r, etc., the results are shown in Table 7 and Table 8. As can be seen from the table, when dill oil and turmeric oil were fumigated for 1 day and 7 days, the LC 50 showed a downward trend; and after 1 day of fumigation, the LC of dill oil in the upper and middle layers of wheat simulation warehouse 50 were lower than that of turmeric oil; after 7 days of fumigation, the LC of dill oil in the upper layer of wheat simulated warehouse was 50Lower than turtle leaf oil, but its middle layer LC 50 Higher than that of turtle leaf oil, and at 14 days, dill oil was in the middle LC 50 This indicates that the permeability of turkeyleaf oil in wheat piles is higher than that of dill oil, that is, wheat has a greater adsorption capacity for dill oil than turkeyleaf oil. Therefore, turkeyleaf oil is more suitable than dill oil for controlling the occurrence and damage of red flour beetles in real warehouses.

[0080] Table 5 Fumigation effects of different concentrations of dill oil on Tribolium castaneum in wheat simulated warehouse (mean ± SE)

[0081]

[0082] Table 6 Fumigation effects of different concentrations of turmeric oil on Tribolium castaneum in wheat simulated warehouse (mean ± SE)

[0083]

[0084] Table 7 Regression analysis of the toxicity of dill oil to Tribolium castaneum in simulated warehouse fumigation

[0085]

[0086] Note: “——” indicates that relevant data were not obtained, the same below.

[0087] Table 8 Regression analysis of the toxicity of turmeric leaf oil to Tribolium castaneum in simulated warehouse fumigation

[0088]

[0089] The above content is a further detailed description of the present invention in conjunction with specific implementation methods. It cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, they can make several simple deductions or substitutions without departing from the concept of the present invention, which should be regarded as falling within the scope of protection determined by the claims submitted for the present invention.

Claims

1. Use of plant essential oils for preventing and controlling stored product pests, characterized in that: The plant essential oil is turmeric oil; and the stored product pest to be controlled is red flour beetle.

2. The use according to claim 1, characterized in that The plant essential oil has fumigation activity against Tribolium castaneum.

3. The use according to claim 1, characterized in that The plant essential oil has contact killing activity against red flour beetle.

4. The use according to claim 1, characterized in that The plant essential oil has repellent activity against red flour beetle.

5. The use according to claim 1, characterized in that The plant essential oil is combined with an adjuvant to prepare a pesticide preparation.

6. The use according to claim 5, characterized in that The pesticide preparation is emulsifiable concentrate, microemulsion and water emulsion.

Images