Application of 2,3-butanedione in attracting gravid female Eupeodes corollae

Abstract

The present invention relates to the application of 2,3-butanedione in attracting gravid female Eupeodes corollae. The application is to use 2,3-butanedione to attract Eupeodes corollae to lay eggs at the pest damage site for controlling the pests. The dosage of the 2,3-butanedione is 100 to 1000 μg.

Description

Technical Field

[0001] The present invention relates to the field of biological control, and particularly to the application of 2,3-butanedione in attracting gravid female Eupeodes corollae. Background Art

[0002] Eupeodes corollae belongs to the family Syrphidae of the order Diptera in the class Insecta, and is widely distributed in regions such as Europe, North America, and Asia. In China, syrphids are more distributed in the southwest and northwest regions, and are also distributed in Fujian Province, Hebei Province, and Jiangsu Province. It is a beneficial insect with dual service functions in the farmland ecosystem: the adults feed on nectar and pollen and can help plants pollinate; the syrphid larvae mainly feed on aphids, thrips, and young lepidopteran larvae, so they can prevent pests. Among them, using natural enemy insects to control pests can effectively reduce environmental pollution and maintain ecological balance, meeting the requirements of ecological regulation, environmental friendliness, and sustainable development.

[0003] It is necessary to explore whether the choice of oviposition sites of Eupeodes corollae is related to chemical odors and which chemical odors are related, which will help to better use natural enemy insects to control pests. Summary of the Invention

[0004] One aspect of the present invention provides the application of 2,3-butanedione in attracting gravid female Eupeodes corollae.

[0005] In a specific embodiment, the application is the application of 2,3-butanedione in attracting gravid female Eupeodes corollae to lay eggs.

[0006] In a specific embodiment, the application is to use 2,3-butanedione to attract Eupeodes corollae to lay eggs at the pest-infested sites for controlling the pests.

[0007] In a specific embodiment, the dosage of 2,3-butanedione is 100 to 1000 μg.

[0008] In a specific embodiment, the pests are at least one of lepidopteran larvae, aphids, whiteflies, mealybugs, leafhoppers, and thrips.

[0009] Advantages of the Present Invention

[0010] The present invention for the first time discovers that 2,3-butanedione can attract pregnant female Syrphidae flies. Using this discovery, 2,3-butanedione can be prepared into a lure core, thereby attracting Syrphidae flies, especially Eupeodes corollae, to lay eggs directionally at the damage sites of harmful insects such as aphids, whiteflies, mealybugs, leafhoppers, thrips or Lepidopteran larvae, which is beneficial to the control of harmful insects such as aphids, whiteflies, mealybugs, leafhoppers, thrips or Lepidopteran larvae. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 Showing the wind tunnel behavioral responses of male and female Eupeodes corollae in different mating states to 100 μg of 2,3-butanedione. Among them, n is the number of test heads of the test subjects.

[0012] Figure 2 Showing the wind tunnel behavioral responses of male and female Eupeodes corollae in different mating states to 1000 μg of 2,3-butanedione. Among them, n is the number of test heads of the test subjects.

[0013] Figure 3 Showing the number of eggs laid by pregnant female Eupeodes corollae attracted by 2,3-butanedione. Among them, 2,3-butanedione / 100 in the abscissa corresponds to a 100 μg odor lure core, and 2,3-butanedione / 1000 corresponds to a 1000 μg odor lure core.

[0014] Figure 4 Showing the oviposition selection preference of pregnant female Eupeodes corollae for 2,3-butanedione. Among them, 2,3-butanedione / 100 in the abscissa corresponds to a 100 μg odor lure core, and 2,3-butanedione / 1000 corresponds to a 1000 μg odor lure core. DETAILED DESCRIPTION OF THE INVENTION

[0015] The above content of the present invention will be further described in detail below in the form of preferred embodiments, but it does not constitute a limitation to the present invention.

[0016] Unless otherwise specified, the reagents in the embodiments of the present invention can be purchased through commercial channels.

[0017] The 2,3-butanedione stock solution can be obtained by purchasing commercially.

[0018] Example 1

[0019] Using n-hexane as a solvent, prepare a 2,3-butanedione lure core:

[0020] 1) Pipette 101 μL (density 0.990 g / mL) of the 2,3-butanedione stock solution and make the volume up to 1000 μL, mix well to obtain a 2,3-butanedione solution with a concentration of 100 μg / μL.

[0021] 2) Mix 100 μg / μL of 2,3-butanedione solution with 900 μL of n-hexane to obtain a 2,3-butanedione solution with a concentration of 10 μg / μL.

[0022] 3) Mix 10 μg / μL of 2,3-butanedione solution with 900 μL of n-hexane to obtain a 2,3-butanedione solution with a concentration of 1 μg / μL.

[0023] 100 μL of the 10 μg / μL 2,3-butanedione solution prepared above was added to a rubber carrier to prepare a 1000 μg odor attractant core.

[0024] 100 μL of the 1 μg / μL 2,3-butanedione solution prepared above was added to a rubber carrier to prepare a 100 μg odor attractant core.

[0025] The female and male Aphididae that had not mated on the third day after eclosion, and the female and male Aphididae that had mated on the third day after eclosion and were pregnant on the fourth day after mating were selected as the test subjects.

[0026] The subjects were starved 4 hours before the wind tunnel test. The wind tunnel behavior chamber was made of acrylic material and was 2.3 m long, 0.7 m wide, and 0.7 m high. Before the test, the wind tunnel behavior chamber was wiped with alcohol and opened in advance for ventilation at a wind speed of 0.22 m / s. The glass mesh cage (7 cm diameter, 10 cm high) used to hold the subjects was wiped with water.

[0027] Before the wind tunnel test, a 10-day-old broad bean seedling (about 10 cm tall, 2 leaves) was placed in a disposable paper cup. The paper cup was completely wrapped with tin foil, leaving only the stem and leaves exposed to the environment. The number of broad bean seedlings was determined based on the number of treatment groups and the number of replicates for each treatment.

[0028] Wind tunnel behavioral testing was conducted from 10:00 AM to 6:00 PM, with the temperature inside the wind tunnel chamber maintained at 25 ± 2°C and relative humidity at 30-40%. During the wind tunnel testing, the wind speed was set at 0.22 m / s. Each lure was placed in the leaf sheath of each broad bean seedling. The seedling was secured upwind of the wind tunnel chamber, ensuring that the leaves did not block the airflow from the upwind direction to the lure. A single test subject was placed in a glass mesh cage, which was then positioned downwind. The subject was allowed to acclimate for 2 minutes. The cage baffle was then removed, and the subject's takeoff, counterflight, attraction, approach, rest, and landing behaviors were observed for a total of 10 minutes. At least 30 subjects were tested per treatment. The behavioral responses of each subject were recorded, and the number of subjects with different behavioral responses was counted and their proportion in the total number of subjects tested was calculated. Wind tunnel behavioral data were analyzed using a chi-square test.

[0029] Among them, the definitions of the six behavioral indicators are as follows:

[0030] Takeoff: The test subject flies out of the glass mesh cage;

[0031] Reverse flight: The test subject makes a directional flight towards the lure core and flies over more than 1 / 2 of the length of the wind tunnel behavior box;

[0032] Attraction: The test subject flies within a range of 30 cm from the lure core;

[0033] Approach: The test subject flies towards the lure core, searches for and locates the lure core, within a range of 10 cm from the lure core;

[0034] Stay: The test subject flies within a range of 30 cm from the lure core and stays for more than 30 s;

[0035] Landing: The test subject lands on the lure core.

[0036] If the test subject has no behavioral response within 5 minutes, it indicates that the test subject has no behavioral response to the test lure core.

[0037] The results are shown in Figure 1 and Figure 2 .

[0038] According to Figure 1 and Figure 2 The results show that the proportions of attraction, stay, approach, and landing behaviors of gravid female insects caused by 2,3-butanedione are significantly increased compared with those of male insects before and after mating and female insects before mating; and 2,3-butanedione cannot cause the approach and landing behaviors of male insects before and after mating, and can hardly cause the approach and landing behaviors of female insects before mating.

[0039] The above results indicate that 2,3-butanedione only has a long-distance attraction effect on gravid female insects and can cause the landing behavior of gravid female insects.

[0040] Example 2

[0041] The preparation method of the used lure core is the same as that in Example 1, and the used concentrations of 2,3-butanedione are 1 μg / μL and 10 μg / μL.

[0042] Take 100 μL of 10 μg / μL 2,3-butanedione solution and add it to the rubber carrier to prepare a 1000 μg odor lure core.

[0043] Take 100 μL of 1 μg / μL 2,3-butanedione solution and add it to the rubber carrier to prepare a 100 μg odor lure core.

[0044] Oviposition selection experiment:

[0045] Female aphid flies that mated on the third day after eclosion and were egg-bearing on the fourth day after mating were selected as test subjects.

[0046] A 10-day-old broad bean seedling (about 10 cm tall, 2 leaves) was placed in a disposable paper cup and completely wrapped with tin foil, with only the stem and leaves exposed to the environment. Five pea aphids of similar size were colonized on the seedling. The number of broad bean seedlings was determined based on the number of treatment groups and the number of replicates for each treatment.

[0047] Each lure was attached to the leaf sheath of a broad bean seedling. For the egg-laying test, seedlings with scented lures were placed at one end of two diagonal corners of a 28 cm × 20 cm × 20 cm insect cage. A control lure was placed at the other end. At 4:00 PM, five subjects were released into each cage, and the process continued until 9:00 PM, for a total egg-laying period of 5 hours (peak egg-laying time for the large gray aphid fly is between 4:00 PM and 9:00 PM). Immediately after the test, the number of eggs laid on each cage containing the different lures was counted. Each cage served as a replicate, and each treatment was replicated five times.

[0048] The oviposition behavior of female larvae was measured using the total egg production and the Oviposition Index (OI). The total egg production = T + C, where T is the egg production of the odor group and C is the egg production of the control group. The specific formula is OI = (TC) / (T + C). Independent sample t-tests were used to analyze the differences in the Oviposition Index and egg production. Figure 3 and Figure 4 .

[0049] according to Figure 3 The results showed that compared with n-hexane, 100 μg and 1000 μg of 2,3-butanedione induced a significantly increased number of eggs laid by pregnant females of the large gray aphid fly, which were 59.89±9.14 and 68.33±10.34 eggs, respectively.

[0050] according to Figure 4 The results showed that compared with n-hexane, the egg-laying females of the large gray aphid fly had a significant preference for laying eggs on 2,3-butanedione at doses of 100 μg and 1000 μg, with the egg-laying indices being 0.37±0.08 and 0.24±0.18, respectively.

[0051] The above results indicate that 2,3-butanedione has oviposition attractant activity to egg-bearing females of the large gray aphid fly.

Claims

1. Application of 2,3-butanedione in attracting gravid female Eupeodes corollae.

2. The application according to claim 1, characterized in that, The application is the application of 2,3-butanedione in attracting gravid female Eupeodes corollae to lay eggs.

3. The application according to claim 1 or 2, characterized in that, The application is to use 2,3-butanedione to attract Eupeodes corollae to lay eggs at the pest damage site for controlling the pests.

4. The application according to claim 3, characterized in that, The dosage of the 2,3-butanedione is 100 to 1000 μg.

5. The application according to claim 3, wherein The pests are at least one of Lepidoptera larvae, aphids, whiteflies, mealybugs, leafhoppers and thrips.

Images