A sorghum aphid repellent

Abstract

The application discloses a sorghum aphid repellent, wherein the efficacy component is trans-2-decenal, and the trans-2-decenal can be configured into a liquid paraffin solution of trans-2-decenal for use, preferably a liquid paraffin solution of 0.1 mu g / mu L-0.5 mu g / mu L trans-2-decenal. The sorghum aphid repellent is prepared from existing chemical products, the components are stable, the preparation method is simple, the repellent effect on the sorghum aphid is obvious, and the sorghum aphid repellent is expected to be used in the prevention and control of the sorghum aphid. The repellent can be used for preventing the harm of the sorghum aphid, the compound in the application is an industrial raw material, the preparation method is simple, the price is low, the compound is safe for human and livestock, and the environment is not polluted, so the application has a wide application prospect.

Description

Technical Field

[0001] This invention relates to an insect repellent, specifically to a repellent for controlling the sorghum aphid Melanaphissacchari (Zehntner, 1897). Background Technology

[0002] Sorghum bicolor (L.) is a crop belonging to the genus Sorghum in the family Poaceae. It has multiple uses, including food, feed, and brewing. This crop is highly adaptable and widely planted, making it the fifth largest cultivated crop in my country. With the adjustment of the agricultural industrial structure, sorghum has enormous development potential and industrial advantages in agricultural production. Among the many factors affecting sorghum yield and quality, the occurrence and damage caused by sorghum diseases and pests are significant. Aphids are one of the most important pests in sorghum production. The sorghum aphid, Melanaphis sacchari (Zehntner, 1897), is an insect belonging to the genus Melanaphis in the family Aphididae of the order Homoptera, and is widely distributed throughout China. Adults and nymphs gather on the undersides of sorghum leaves, spreading upwards from the lower leaves, sucking sap and excreting large amounts of honeydew that drips onto the stems and leaves, giving them a shiny appearance. This leads to a significant depletion of nutrients in the host plant, affecting photosynthesis and product quality. Mild infestations cause leaves to turn red, while severe infestations result in leaf withering, unfilled grains, or failure to produce ears, leading to significant yield reductions or even total crop failure. Studies have reported that damage caused by sorghum aphids typically reduces yields by around 15%, but in years of severe outbreaks, untimely control measures can result in yield reductions exceeding 30%, and in some cases, losses as high as 50%.

[0003] Sorghum is an important raw material crop for my country's liquor industry. In recent years, high-quality liquor producers, such as those producing Guizhou-style sauce-flavored liquor, have had a strong demand for organic sorghum. Currently, aphids on sorghum are mostly controlled by chemical methods. However, the extensive use of chemical pesticides has led to aphid resistance. At the same time, the market demand for organic sorghum is constantly expanding. Therefore, there is an urgent need to find a method to control aphids on sorghum that can replace chemical pesticides. Summary of the Invention

[0004] The purpose of this invention is to provide a sorghum aphid repellent that can be stably released and has a good control effect.

[0005] A sorghum aphid repellent includes a solvent and an active ingredient, wherein the active ingredient is trans-2-decenal.

[0006] The solvent is liquid paraffin.

[0007] The concentration of trans-2-decenal is 0.1 μg / μL to 0.5 μg / μL.

[0008] The sorghum aphid repellent was prepared using the following method: a 100 μg / μL liquid paraffin solution of trans-2-decenal was prepared, and then the trans-2-decenal / liquid paraffin solution was diluted with liquid paraffin to the desired concentration of trans-2-decenal solution. The trans-2-decenal was purchased from Sigma-Aldrich.

[0009] Application of trans-2-decenal in repelling sorghum aphids.

[0010] The trans-2-decenal was formulated into a liquid paraffin solution and used as a repellent for sorghum aphids.

[0011] The concentration of trans-2-decenal is 0.1 μg / μL to 0.5 μg / μL in a trans-2-decenal liquid paraffin solution.

[0012] The concentration of trans-2-decenal is 0.5 μg / μL of trans-2-decenal liquid paraffin solution.

[0013] The application described involves spraying trans-2-decenal onto sorghum leaves infested with sorghum aphids.

[0014] Based on previous olfactory response screening, this invention has identified a compound, trans-2-decenal, that repels sorghum aphids. This compound is effective in repelling sorghum aphids, is an industrial raw material, has a simple preparation method, is inexpensive, is safe for humans and animals, does not pollute the environment, and has broad application prospects. Attached Figure Description

[0015] Figure 1 This study was conducted to select the repellent effects of various volatile substances on sorghum aphids. Detailed Implementation

[0016] The following embodiments are further illustrations of the present invention, but not limitations thereof.

[0017] All chemical reagents used were commercially available.

[0018] Example 1:

[0019] The concentration of the reagent used is:

[0020] 1) A 0.5 μg / μL solution of trans-2-decenal, diluted with liquid paraffin.

[0021] 2) A 0.1 μg / μL solution of trans-2-decenal, diluted with liquid paraffin.

[0022] The above solution is prepared as follows: First, prepare a 100 μg / μL trans-2-decenal / liquid paraffin solution. Mix trans-2-decenal and liquid paraffin, shake to mix evenly, dissolve trans-2-decenal, and prepare a liquid solution. Then, dilute the solution with liquid paraffin to the above concentrations in sequence to prepare the sorghum aphid repellent of the present invention.

[0023] 1. Sorghum aphids were collected from Shiban Town, Bozhou District, Zunyi City, Guizhou Province, and were reared on sorghum plants in the greenhouse of Guizhou University. The entire plant was placed in the insect rearing room at a temperature of 25±2℃, a humidity of 65±5%, and a light rhythm of 16L:8D.

[0024] 2. Behavioral Experiment of Sorghum Aphid

[0025] Behavioral observations of sorghum aphids were conducted using a Y-shaped olfactory apparatus. The Y-shaped olfactory apparatus had two arms and a straight tube, each 10 cm long and 1.5 cm in diameter. The airflow rate was controlled at 250 mL / min using a flow meter. Sorghum aphids were used in the experiment. One aphid was introduced into the tube at each experiment, and observation lasted 10 minutes. If the aphid did not make a choice, it was recorded as no response; if it made a choice, the data was recorded accurately. Every 10 aphids were tested, the Y-shaped tube was reversed to eliminate the influence of the environment on the experimental results. After testing every 20 aphids, the Y-shaped tube was first cleaned with acetone, then the inner wall of the olfactory apparatus was wiped with cotton wool soaked in ethanol, and finally rinsed with distilled water and dried in an oven. The entire experiment was conducted in a behavioral chamber. During the experiment, to encourage more sorghum aphids to crawl to the junction of the two arms of the Y-shaped olfactory apparatus and make a choice, a Y-shaped copper wire was placed inside the Y-shaped olfactory apparatus. The entire behavioral experiment was conducted at room temperature (22-25℃), and the experiment was repeated 5-7 times, with 10 worms each time.

[0026] During the experiment, to encourage more sorghum aphids to crawl to the junction of the two arms of the Y-shaped tube and thus make a selection, a Y-shaped copper wire was placed inside the Y-shaped tube. The entire behavioral experiment was conducted at room temperature (22-25℃). A stable airflow of 400 ml / min was introduced into each arm of the Y-shaped tube using an electric pump. The airflow first passed through activated carbon filtration and then was humidified by a humidification tower. The airflow delivered by the electric pump first passed through the two arms of the Y-shaped tube to reach the junction of the two arms, and then converged and flowed out from the bottom of the Y-shaped tube.

[0027] The repellent effects of 0.5 μg / μL and 0.1 μg / μL trans-2-decenal on sorghum aphids were tested using the method described above. Analogs of trans-2-decenal, including cis-4-decenal, trans-4-decenal, trans-2-hexenal, trans-2-octenal, cis-3-hexenal, (E,Z)-2,4-decadienal, and (Z,Z)-2,4-decadienal, were also tested. Eleven compounds, including D-limonene, trans-β-farnesene (EBF), and tetradecene, were also tested, with all compounds having a purity >98%. The testing methods were identical to those for trans-2-decenal. Specific results are as follows: Figure 1 As shown.

[0028] Depend on Figure 1 It can be seen that 0.5 μg / μL and 0.1 μg / μL of trans-2-decenal can effectively repel sorghum aphids, exhibiting a high repellency rate, which is beneficial for the ecological control of sorghum aphids. This demonstrates that the sorghum aphid repellent of the present invention has good efficacy.

[0029] Example 2:

[0030] The concentration of the reagent used is:

[0031] 1) A 0.1 μg / μL solution of trans-2-decenal, diluted with liquid paraffin.

[0032] 2) A 0.5 μg / μL solution of trans-2-decenal, diluted with liquid paraffin.

[0033] The preparation method of the above solutions is as follows: First, prepare a 100 μg / μL trans-2-decenal / liquid paraffin solution, shake to mix evenly, and then dilute the trans-2-decenal / liquid paraffin solution sequentially with liquid paraffin to the required concentration of trans-2-decenal solution, thereby preparing the sorghum aphid repellent of the present invention. Trans-2-decenal is a liquid preparation, and is directly diluted with liquid paraffin to the above concentrations.

[0034] 1. Collect several sorghum leaves with a large number of sorghum aphids.

[0035] 2. Using a pipette, gently add 1 μL of 0.1 μg / μL trans-2-decenal solution to the leaf, recording the effect every 2 minutes for a total of 4 minutes. Calculate the adult insect movement rate to measure the repellent effect of trans-2-decenal. The specific results are shown in Table 1:

[0036] 3. The repellent effects of 0.1 μg / μL and 0.5 μg / μL trans-2-decenal on sorghum aphids were tested using the method described above.

[0037] 4. Liquid paraffin solution was used as a control in all the above experiments, and the experimental treatment methods were the same.

[0038] Table 1: Repellency rate of trans-2-decenal against sorghum aphids

[0039]

[0040] As can be seen from Table 1, 0.1 μg / μL and 0.5 μg / μL trans-2-decenal have significant repellent effects on sorghum aphids, indicating that the sorghum aphid repellent of the present invention has good efficacy.

Claims

1. Application of trans-2-decenal as an active ingredient in repelling sorghum aphids.

2. According to claim 1, the trans-2-decenal is formulated into a liquid paraffin solution and used as a repellent for sorghum aphids.

3. According to claim 2, a liquid paraffin solution of 100 μg / μL trans-2-decenal is prepared, and then the trans-2-decenal solution is diluted with liquid paraffin to the desired concentration of trans-2-decenal solution.

4. The application according to claim 3, wherein the concentration of trans-2-decenal is a trans-2-decenal liquid paraffin solution of 0.1 μg / μL to 0.5 μg / μL.

5. The application according to claim 4, wherein the concentration of trans-2-decenal is a trans-2-decenal liquid paraffin solution of 0.5 μg / μL.

6. The application according to any one of claims 1-5 is to spray trans-2-decenal onto sorghum leaves infested with sorghum aphids.

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