Application of citric acid or decanoic acid in improving flight capability of irradiation sterile male codling moth

Abstract

The invention belongs to the field of insect breeding, and particularly discloses an application of citric acid or decanoic acid in improving the flight capability of irradiated sterile male codling moths, and within 24 hours after eclosion of the X-ray irradiated codling moths, a sucrose solution of citric acid with the concentration of 4 mM or a sucrose solution of decanoic acid with the concentration of 250 mu M is used for feeding the codling moths for 48 hours. Compared with the prior art, the method has the advantages that citric acid or capric acid feeding treatment is proved to be capable of improving the flying capability of irradiating the male sterile codling moth, so that the success rate of the male sterile codling moth to dove and the control effect on the population can be improved.

Description

Technical Field

[0001] The invention relates to the field of insect breeding, in particular to the application of citric acid or capric acid in improving the flight ability of irradiated sterile male codling moths. Background Art

[0002] The Sterile Insect Technique (SIT) is an important component of large-scale integrated pest management. This technology releases a large number of sterile male insects of target pests into the control area, allowing them to mate with wild female insects to produce sterile offspring, thereby gradually suppressing the target pest population. Insect flight plays a vital role in various activities such as courtship, foraging and migration. Previous studies have shown that exposure to X-ray irradiation, even at optimal doses, can have a negative impact on the flight ability of Cydia pomonella, which will directly affect the spread distance of sterile insects in the field and the success rate of courtship and mating.

[0003] Energy metabolism is the main energy source for insect flight. Citric acid is an important intermediate metabolite in the tricarboxylic acid cycle. It is the metabolite of citrate synthase, the first key rate-limiting enzyme in the tricarboxylic acid cycle, and determines the progress of the entire tricarboxylic acid cycle. Decanoic acid is an activator of citrate synthase, which can activate citrate synthase to produce citric acid to activate or start the tricarboxylic acid cycle. Studies have shown that environmental pollution causes plants to accumulate cadmium, and the flying ability of the bear's peak is impaired after sucking plant nectar. Exogenous supplementation of citric acid or decanate can partially restore the flying ability of the bear's peak under cadmium stress, which is beneficial for it to pollinate a wider range of plants in the field. However, it is still unclear whether feeding treatments with citric acid or decanate can improve the flying ability of irradiated sterile males of the codling moth, thereby increasing its diffusion distance and courtship and mating success rate in the field. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides the use of citric acid or capric acid in improving the flight ability of irradiated sterile male codling moth.

[0005] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0006] The application of citric acid or capric acid in improving the flight ability of irradiated sterile male codling moth is that within 24 hours after the male codling moth irradiated by X-rays emerges, the codling moth is fed with a sucrose solution of 4 mM citric acid or a sucrose solution of 250 μM capric acid for 48 hours.

[0007] Furthermore, the irradiation is performed using X-rays, and the X-ray dose is 200 Gy.

[0008] Compared with the prior art, the present invention proves that feeding treatment with citric acid or capric acid can improve the flight ability of irradiated sterile male codling moth, thereby improving the courtship success rate of sterile male codling moth and the control effect on the population. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 Effects of citric acid or capric acid feeding on the energy metabolism of sterile male codling moth: (a) citric acid content in sterile male codling moth after exogenous supplementation of capric acid; (b) CS2 expression level in sterile male codling moth after exogenous supplementation of capric acid; (c) CS activity in sterile male codling moth after exogenous supplementation of capric acid; (d) ATP content in sterile male codling moth after exogenous supplementation of capric acid; (e) ATP content in sterile male codling moth after exogenous supplementation of citric acid.

[0010] Figure 2 Effects of citric acid or decanic acid feeding treatments on the flight performance of sterile male codling moth: (a) Effects of 4 mM citric acid solution feeding treatments and 250 μM decanic acid solution feeding treatments on the maximum flight speed of sterile male codling moth; (b) Effects of 4 mM citric acid solution feeding treatments and 250 μM decanic acid solution feeding treatments on the average flight speed of sterile male codling moth; (c) Effects of exogenously supplemented citric acid or decanic acid on the flight time of sterile male codling moth; (d) Effects of exogenously supplemented citric acid or decanic acid on the flight distance of sterile male codling moth. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the invention.

[0012] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available; disposable plastic cup (320 mL); citric acid (Beijing Solebold Technology Co., Ltd., Beijing, China); capric acid (Beijing Solebold Technology Co., Ltd., Beijing, China); disposable transparent plastic box (1500 mL); sulfuric acid paper; shower cap; culture dish; bottle cap; hot melt adhesive; 502 glue; ice box.

[0013] The origin, artificial breeding methods and breeding conditions of codling moth:

[0014] 1. Methods of feeding test insects

[0015] The test insects were donated by the Institute of Plant Protection, Chinese Academy of Agricultural Sciences, and the Agricultural Invasive Biological Control Detection Laboratory. They were raised for more than 70 generations in the Insect Toxicology Laboratory of Shenyang Agricultural University without being treated with pesticides or other radiation.

[0016] 2. Rearing conditions

[0017] The photoperiod is 8h dark period: 16h light period, the temperature is 26±1℃, and the relative humidity is 60%~70%.

[0018] 3. Feeding methods

[0019] Artificial feed formula: For details, see patent application number: 201910839547.3. The feed is prepared from the following raw materials in proportion by mass: 4-8% soybean meal, 4-8% corn meal, 1-3% sucrose, 2-4% yeast powder, 1.2-2% apple dry powder, 0.2-0.5% ascorbic acid, 0.15-0.4% methyl paraben, 0.05-0.2% sorbic acid, 0.01-0.03% cholesterol, 16-18% tomato paste, 1-1.4% agar, and 54.47%-71.59% water.

[0020] Larvae rearing method: Collect the egg paper on the top of the egg-laying box every day and place the egg paper in an artificial climate box. After the eggs hatch, pick up the newly hatched larvae with a brush and gently place them on the surface of the artificial diet of the codling moth and rear them until the end of the 5th instar larvae.

[0021] Rearing of pupae and adults: prepare a disposable transparent plastic box, lay a layer of multi-layered paper towels on the bottom of the box, pick out the 5th instar larvae from the centrifuge tube, put them in the box, wait for them to pupate in the box, check the pupation situation in the box every day, put the pupae of the same day into the culture dish, distinguish the male and female according to the morphological characteristics of the pupae, and mark the pupation date. Before the adult emerges, cut a 5cm*4cm square hole on each side of the disposable transparent plastic box, apply hot melt glue evenly around the bottom of the box, stretch the shower cap and stick it inside the box, and cover the top of the box with the shower cap on all sides. Stick a bottle cap in the center of the bottom of the box, put a piece of cotton soaked in 10% honey water in the bottle cap, put the pupae before emergence into the rearing box, fold the sulfuric acid paper into a 3cm*2cm grid and cover the upper part of the box as a medium for collecting eggs, and buckle the box cover on the upper part of the sulfuric acid paper and fix it with a rubber band, add 10% honey water every 2 days, and replace the egg paper every 1-2 days.

[0022] Example 1: Effects of citric acid or capric acid feeding on energy metabolism of sterile male codling moth

[0023] The specific process is as follows: Within 24 hours after the male X-ray-irradiated codling moth eclosion, it was fed with a sucrose solution containing 4mM citric acid for 48 hours. A 100mM decanoic acid stock solution was dissolved in DMSO to prepare a decanoic acid supplement. Within 24 hours, the codling moth was randomly divided into three groups: a control group (0+DMSO group), an X-ray irradiation group (200Gy+DMSO group) and a decanoic acid supplement group (200Gy+decanoic acid group). The control codling moth was fed with a sucrose solution supplemented with DMSO. A 100mM decanoic acid supplement was added to the sucrose solution of the 200Gy X-ray irradiation group to make the final concentration of decanoic acid in the sucrose solution reach 250μM. These nutrient solutions were fed to codling moth for 48 hours.

[0024] Prepare several 320mL disposable plastic cups, place sterile male codling moths that have emerged for 24 hours into the disposable transparent plastic cups, then drip 4mM citric acid solution or 250μM capric acid solution on the bottom of the plastic cups, take out the moths after 48 hours of feeding treatment, and measure the citric acid content, ATP content, citrate synthase (CS) activity, and expression of CS2, a key gene encoding citrate synthase.

[0025] Data processing was performed using the t-test method for significance analysis. The experimental results were expressed as mean ± standard error and plotted using Graphpad Prism 5 software. Figure 1 shown.

[0026] Depend on Figure 1 From (a) in the figure, we can see that exogenous supplementation of decanoic acid can increase the citric acid content in the sterile male codling moth to normal levels; Figure 1 As shown in (b), the expression level of CS2 in sterile male codling moth increased significantly after exogenous addition of decanoic acid. Figure 1 From (c) in the figure, we can see that exogenous supplementation of decanoic acid can increase the CS activity in sterile male codling moths to normal levels; Figure 1 From (d) in the figure, we can see that exogenous supplementation of decanoic acid can increase the ATP content in sterile male codling moths to normal levels; Figure 1 From (e) in the figure, we can see that exogenous supplementation of citric acid can increase the ATP content in sterile male codling moth to normal levels. In summary, citric acid or capric acid feeding treatments have an impact on the energy metabolism of sterile male codling moth.

[0027] Example 2: Effects of citric acid or capric acid feeding treatment on flight performance of sterile male codling moth

[0028] The flight performance was statistically analyzed using the FXMD-24-USB insect flight information system. The effects of citric acid or capric acid feeding on the flight performance of sterile male codling moths were shown in Figure 2. Figure 2 shown.

[0029] Depend on Figure 2 (a) Figure 2 As shown in (b), the 4 mM citric acid solution feeding treatment and the 250 μM capric acid solution feeding treatment had no effect on the maximum flight speed and average flight speed of sterile male codling moths; Figure 2 As shown in (c), the flight time of sterile male codling moth supplemented with citric acid or capric acid was significantly increased compared with that of sterile male codling moth that was not irradiated, and was almost the same as that of non-irradiated male codling moth. Figure 2 As shown in (d), the flight distance of sterile male codling moth supplemented with citric acid or capric acid was significantly increased compared with that of unirradiated sterile male codling moth, and was almost consistent with the flight distance of non-irradiated male codling moth.

[0030] The invention proves that the feeding treatment of citric acid or capric acid can improve the flight ability of irradiated sterile male codling moth, and further can improve the courtship success rate of sterile male codling moth and the control effect on the population.

[0031] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. The use of citric acid or capric acid in improving the flight ability of irradiated sterile male codling moth, characterized in that: Within 24 hours after the male X-ray-irradiated codling moth eclosion, the codling moth was fed with a sucrose solution of 4 mM citric acid or a sucrose solution of 250 μM capric acid for 48 hours.

2. The use of citric acid or capric acid according to claim 1 in improving the flight ability of irradiated sterile male codling moth, characterized in that: The irradiation is performed using X-rays, and the dose of the X-rays is 200 Gy.

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