Collecting device and method for spotted wing drosophila melanogaster eggs

Abstract

The invention relates to the technical field of fly egg collection, and discloses a collection device for spotted wing drosophila melanogaster eggs, the collection device comprises a collection container with two open ends and a live yeast flat plate, a net body is arranged at the bottom of the collection container, the caliber of the net body is 80-100 meshes, and the size of the live yeast flat plate is matched with the size of the collection container. According to the method, live yeast powder is used for making a pasty disc to attract the drosophila melanogaster to lay eggs in the pasty disc, then the yeast is washed away with flowing clear water, the activity of the yeast is utilized, the yeast cannot harden and block meshes in the washing process, the eggs are large and stay on the net to be collected, and compared with the prior art, the method is used for collecting the eggs of the spotted wing drosophila melanogaster in a large scale, and the yield of the spotted wing drosophila melanogaster is increased. And the collection efficiency in the prior art is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of fly egg collection, and in particular to a device and method for collecting spotted-wing drosophila eggs. Background Art

[0002] The spotted-wing drosophila is an emerging pest that has caused serious damage to the fruit industry in recent years. It can lay eggs directly in ripe or about to ripen cherries, peaches, European plums, grapes, strawberries, raspberries, blueberries, persimmons, tomatoes and other fruits with soft skin. After the eggs hatch into larvae, they feed on the flesh inside the fruit and accelerate the decay and deterioration of the fruit, resulting in a decrease in fruit yield and a serious impact on fruit sales. The spotted-wing drosophila has now caused damage worldwide. Taking the United States as an example, the spotted-wing drosophila can cause about $511 million in losses to the strawberry, cultivated blueberry, raspberry, blackberry and cherry industries in California, Washington and Oregon each year. From 2009 to 2014, the spotted-wing drosophila in California caused about $39.8 million in economic losses and $8 million in additional control costs to the raspberry industry each year. The spotted-wing drosophila has biological and ecological characteristics such as strong fertility, short life cycle, alternation of generations and strong adaptability. The invasive biology and control strategies of the spotted-wing drosophila have been a hot topic in agricultural science research around the world in recent years. Relevant companies and research institutes around the world are studying technical measures to prevent and control it. Each study requires a large number of spotted-wing drosophila eggs as research materials.

[0003] Traditionally, the eggs of spotted-winged Drosophila are mostly collected by referring to the device for collecting common Drosophila eggs. A juice plate containing agar (such as apple juice or grape juice) is prepared, and a little yeast paste is applied on the plate to supplement the nutrition of Drosophila. Drosophila are allowed to lay eggs on the juice plate, and then the juice plate is rinsed with water and the eggs are collected with a brush.

[0004] This method is applicable to common fruit flies, but spotted-wing fruit flies are different from most conventional fruit flies. Spotted-wing fruit flies have unique biological characteristics. The female ovipositor is larger, and the female likes to lay eggs inside the juice plate, leaving only respiratory hairs outside. Therefore, a large number of eggs cannot be collected by sweeping the surface of the juice plate with a brush. The method of picking out eggs with tweezers is inefficient and easy to cause mechanical damage, which ultimately affects the survival and hatching rate of the eggs. Summary of the invention

[0005] The purpose of the present invention is to solve the problems existing in the prior art and to propose a device and method for collecting spotted-wing drosophila eggs.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: The device for collecting spotted-wing drosophila eggs comprises a collection container with openings at both ends, a mesh body is arranged at the bottom of the collection container, and the caliber is between 80-100 meshes, and a live yeast plate is arranged on the mesh body, and the size of the live yeast plate is adapted to the size of the collection container.

[0007] The method for collecting spotted-wing drosophila eggs uses a device for collecting spotted-wing drosophila eggs, and comprises the following steps: Step 1: Mix appropriate amount of yeast powder and water to make a live yeast plate and fill it at the bottom of the culture dish; Step 2, placing the culture dish in a fruit fly egg collector, transferring the spotted-wing drosophila in the egg-laying period into the egg collector, and waiting for the spotted-wing drosophila to feed on the yeast and lay eggs on the yeast plate; Step 3, after the spotted-wing drosophila lays eggs, remove the spotted-wing drosophila; Step 4, transferring the yeast containing the fruit fly eggs from the culture dish into a collection device; Step 5: Rinse off the yeast with running water, leaving the fruit fly eggs on the gauze to complete the collection.

[0008] Preferably, in step 1, the yeast powder is live yeast, the water used is ultrapure water, the temperature is lower than 40° C., and the live yeast plate is dried until there is no residual water on the surface.

[0009] Preferably, in step 3, the spotted-wing drosophila is removed 6 hours after the spotted-wing drosophila lays eggs.

[0010] Preferably, the live yeast is dry yeast for baking, brewer's yeast or beer yeast.

[0011] Compared with the prior art, the present invention has the following beneficial effects: The present invention uses live yeast powder to make a paste disk to attract fruit flies to lay eggs in it, and then uses running clean water to wash away the yeast. The activity of the yeast is utilized so that the mesh will not be compacted and blocked during washing, and larger eggs will be retained on the net and collected. Compared with the prior art, the present invention is used for collecting eggs of spotted-wing drosophila on a large scale, can collect eggs more simply and efficiently, is easy to operate, and has high survival rate and hatching rate of the collected eggs, effectively improving the collection efficiency of the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A three-dimensional diagram of the device for collecting spotted-wing drosophila eggs proposed by the present invention; Figure 2 An exploded schematic diagram of the device for collecting spotted-wing drosophila eggs proposed by the present invention; Figure 3 Schematic diagram of the interior of a traditional juice plate for spotted-wing Drosophila egg laying; Figure 4 A comparison of the number of fruit fly eggs collected by the traditional juice tray and the new yeast tray; Figure 5 A schematic diagram of the method for collecting spotted-wing Drosophila eggs proposed by the present invention showing that the Drosophila lays eggs in an egg-laying chamber with a yeast plate at the bottom; Figure 6Schematic diagram of the yeast on the net being washed away by clean water, leaving eggs stuck to the net bag.

[0013] In the figure: 1. Collection container; 2. Net body. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0015] Reference Figure 1 and Figure 2 The device for collecting spotted-wing drosophila eggs comprises a collecting container 1 with openings at both ends and a live yeast plate. A net body 2 with a diameter of 80 mesh, 90 mesh or 100 mesh is arranged at the bottom of the collecting container 1. The size of the live yeast plate is adapted to the size of the collecting container 1. The collecting container 1 comprises two tubes screwed together by threads, and the net body is a flexible net bag, which is located between the two tubes and fixed between the two tubes by a screw-joined structure of the two tubes.

[0016] like Figure 5 and Figure 6 As shown, the method for collecting spotted wing drosophila eggs, using a device for collecting spotted wing drosophila eggs, comprises the following steps: Step 1: Make a yeast plate at the bottom of a 60 mm culture dish. After adding a small amount of ultrapure water, sprinkle live yeast evenly on it and stir it with tweezers until it becomes a paste. When the yeast paste is half dry, sprinkle a small amount of yeast powder evenly to complete the yeast plate. Step 2: Collect adult fruit flies 3-8 days after emergence, about 100 female fruit flies, stun them with carbon dioxide, and place them in an egg-laying cup containing a yeast plate to allow the fruit flies to lay eggs; Step 3, after the spotted-wing drosophila lays eggs, remove the spotted-wing drosophila; Step 4: Retrieve the yeast tray, scoop out the yeast (which contains a lot of eggs), and place it in a collection device with a pre-installed net; Step 5: Rinse off the yeast with running water, leaving the fruit fly eggs on the gauze net to complete the collection. Since the yeast in this method is alive and composed of countless tiny fungal cells, it will not become hardened and block the mesh. If the eggs are large, they will be retained on the net and collected.

[0017] In this embodiment, in step 1, live yeast is used as yeast powder, ultrapure water is used, and the temperature is lower than 40° C. The prepared live yeast plate is dried until no residual water is left on the surface.

[0018] In this embodiment, in step 3, the spotted-wing drosophila is removed 6 hours after the spotted-wing drosophila lays eggs.

[0019] In this embodiment, the live yeast is dry yeast for baking, brewer's yeast or beer yeast.

[0020] The method uses live yeast powder to make a paste disk to replace the fruit plate containing agar, so as to attract fruit flies to lay eggs therein, and then uses running clean water to wash away the yeast. The activity of the yeast is utilized so that the yeast will not become hardened and clog the mesh during washing, and the eggs are relatively large and are retained on the net to be collected. Compared with the prior art, the present invention is used for collecting the eggs of spotted-wing drosophila on a large scale, and based on the difference in the pore size of the net basket and the high water solubility of live yeast, irrelevant components are removed, and eggs of target insects are collected in large quantities. The eggs can be collected more simply and efficiently, and are easy to operate. The survival rate and hatching rate of the collected eggs are both high, and the collection efficiency of the prior art is effectively improved.

[0021] The insect eggs collected by the collection method of the present invention can be used for: 1. The collected eggs can be sterilized to obtain eggs without bacterial contamination for scientific research; 2. Collect eggs for egg injection and CRISPR / Cas9 gene editing to provide sufficient materials for the construction of transgenic insect strains.

[0022] In order to verify the effect of the present invention on the spotted wing drosophila, the conventional collection method and the collection method proposed by the present invention were respectively used for the spotted wing drosophila and the melanogaster drosophila to conduct experimental comparisons. The spotted wing drosophila and the melanogaster drosophila were subjected to the following process: Traditional collection method: Prepare a juice plate containing agar (the juice can be apple juice or grape juice) coated with fresh yeast paste, place 100 fruit flies on the juice plate to lay eggs for 5 hours, and the fruit flies lay eggs inside the juice plate (such as Figure 3 As shown), finally use a brush to sweep the surface of the juice plate to collect fly eggs.

[0023] The collection method of the present invention comprises placing 100 fruit flies on a yeast plate to lay eggs for 5 hours, and collecting the eggs by the present invention.

[0024] The number of eggs laid by Drosophila on the two plates and the number of eggs finally collected and used for downstream experiments were counted. Fisher's exact test was used to statistically analyze the data. It was found that there was a significant difference between the number of Drosophila eggs collected by the traditional juice plate and the new yeast plate (p<0.0001). The number of Drosophila eggs collected by the traditional juice plate was about 1 / 10 of that of the new yeast plate (e.g. Figure 4 The number of Drosophila melanogaster eggs was not significantly different between the two methods (p=0.6071).

[0025] The above results show that the traditional method no longer has an advantage when treating the new pest spotted wing drosophila. The method of the present invention has a good effect on spotted wing drosophila and can collect eggs more simply and efficiently. The present invention is easy to operate, and the survival rate and hatching rate of the collected eggs are both high.

[0026] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for collecting spotted-wing drosophila eggs, characterized in that: It comprises a collecting container with openings at both ends. A mesh body is arranged at the bottom of the collecting container, and the caliber is between 80-100 meshes. A live yeast plate is arranged on the mesh body, and the size of the live yeast plate is adapted to the size of the collecting container.

2. A method for collecting spotted-wing drosophila eggs, using the spotted-wing drosophila egg collecting device according to claim 1, characterized in that: The following steps are involved: Step 1: Mix appropriate amount of yeast powder and water to make a live yeast plate and fill it at the bottom of the culture dish; Step 2, placing the culture dish in a fruit fly egg collector, transferring the spotted-wing drosophila in the egg-laying period into the egg collector, and waiting for the spotted-wing drosophila to feed on the yeast and lay eggs on the yeast plate; Step 3, after the spotted-wing drosophila lays eggs, remove the spotted-wing drosophila; Step 4, transferring the yeast containing the fruit fly eggs from the culture dish into a collection device; Step 5: Rinse off the yeast with running water, leaving the fruit fly eggs on the gauze to complete the collection.

3. The method for collecting spotted-wing drosophila eggs according to claim 2, characterized in that In the step 1, live yeast is used as yeast powder, ultrapure water is used, and the temperature is lower than 40° C. The live yeast plate is dried until there is no residual water on the surface.

4. The method for collecting spotted-wing drosophila eggs according to claim 3, characterized in that: In the step 3, the spotted-wing drosophila is removed 6 hours after the spotted-wing drosophila lays eggs.

5. The method for collecting spotted-wing drosophila eggs according to claim 3, characterized in that: The live yeast is dry yeast for dough making, brewer's yeast or beer yeast.

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