A device and method for quickly separating plant cyst nematode cysts

Abstract

The present invention discloses a rapid separation device for plant cyst nematode cysts, which is composed of an outer cylinder and an inner cylinder, wherein the inner cylinder is fixed inside the outer cylinder, and both the outer cylinder and the inner cylinder are cylindrical with an upper end open and a bottom sealed; one or more filter windows are arranged on the upper part of the inner cylinder, and the filter windows make the inner cylinder and the outer cylinder communicate with each other, and the filter windows are covered with a 18-25 mesh screen, and a circle of adsorption filter paper tightly surrounding the inner wall of the outer cylinder is arranged on the inner wall. The present invention also discloses a method for rapid separation of plant cyst nematode cysts using the device. The device of the present invention has low cost and fast separation speed, and can separate one sample within 10 minutes, has high collection efficiency, and the obtained sample to be observed is cleaner.

Description

Technical Field

[0001] The invention belongs to the technical field of plant nematode separation and identification, and specifically relates to a device for quickly separating cysts of plant Sporangiophora or Glomerophorus nematodes and a method for quickly separating cysts by using the device. Background Art

[0002] Plant nematodes belong to the phylum Nematodes in invertebrates. They can parasitize plant roots, stems, leaves, fruits, seeds and other parts. There are many species and they cause serious damage. According to incomplete statistics, the economic losses of agricultural and forestry crops caused by plant nematodes are more than hundreds of billions of yuan each year. In the list of quarantine pests for foreign plants published by my country in 2007, 20 species (genera) of nematodes are quarantine nematodes, and the actual number of species is more than 200.

[0003] Among plant parasitic nematodes, cyst nematodes (including cyst nematodes and spherosporangiate nematodes, etc.) are important pathogens that cause plant diseases. Potato golden nematodes, potato white nematodes, soybean cyst nematodes, etc. all cause serious damage to host plants. Whether it is domestic agricultural and forestry production or entry-exit plant quarantine, it is necessary to separate and identify nematodes to protect the safety of agricultural and forestry production. This type of nematode invades the host as a second-instar larvae, and the head enters the host root and then grows fixedly, gradually develops and swells to form cysts and then falls off. Separating cysts is an important part of identifying and studying nematodes. At present, the main methods for separating cysts of cyst nematodes are Fenwich floater method, soil suspension screening method, sucrose liquid centrifugation method, etc. The above methods each have advantages and disadvantages. The main problem is that the operation is relatively cumbersome, and there are many impurities in the separation liquid, which is not conducive to the observation and counting of cysts. Summary of the invention

[0004] In view of the problems existing in the prior art, the purpose of the present invention is to provide a rapid separation device and method for plant cyst nematode cysts, which can quickly separate cysts from soil samples and be used for species identification, field investigation and efficacy evaluation of cyst nematodes. The method is convenient, highly operational and effective.

[0005] The technical solution adopted by the present invention is:

[0006] A rapid separation device for plant cyst nematode cysts, the device comprising an outer cylinder and an inner cylinder, the inner cylinder being fixed inside the outer cylinder, the outer cylinder and the inner cylinder being both cylindrical with an open upper end and a sealed bottom; at least one filter window is arranged on the upper part of the inner cylinder, the filter window enables the inner cylinder and the outer cylinder to communicate, the filter window is covered with a sieve of 18 to 25 meshes, and a circle of adsorption filter paper tightly surrounding the inner wall of the outer cylinder is arranged on the inner wall of the outer cylinder.

[0007] The plant cyst nematode cysts refer to cysts of the genus Sporangiophore nematodes or the genus Coccidiophore nematodes.

[0008] Furthermore, the screen can be fixed on the filter window or detachably connected to the filter window. The size of the screen should be larger than the size of the filter window so that the screen completely covers the filter window.

[0009] The detachable connection can be in various ways such as snap-on or slot-on. For example, the screen is installed in a screen frame that matches the filter window, and a slot is set at the edge of the filter window on the inner wall or outer wall of the inner cylinder. The screen frame is inserted into the slot to achieve a slot-on detachable connection. Alternatively, holes are punched on the frame of the screen frame, and corresponding protrusions are set at the edge of the filter window on the outer wall of the inner cylinder. The holes on the screen frame are aligned with the protrusions and pressed to assemble, so as to achieve a snap-on detachable connection. There are many ways to achieve this type of detachable connection, all of which are applicable to the present invention.

[0010] More preferably, the rectangular screen is rolled into a cylinder, and the screen cylinder is placed in the inner cylinder. The elasticity of the screen is utilized to make the screen cylinder close to the inner wall of the inner cylinder, and the screen can also be assembled to completely cover the filter window.

[0011] The height of the screen cylinder should be greater than the height from the top of the filter window to the bottom of the inner cylinder. The length of the screen cylinder is greater than the circumference of the inner wall of the inner cylinder.

[0012] The filter window may be in various shapes, and preferably the bottom of the window is a straight line parallel to the bottom of the cylinder, and more preferably a rectangle.

[0013] When there are more than two filter windows, the bottom ends of the filter windows should be at the same height of the inner cylinder, and filter windows of different heights should not be arranged.

[0014] The bottom end of the filter window is preferably lower than the top end of the outer cylinder.

[0015] The adsorption filter paper on the inner wall of the outer cylinder can be formed by rolling a rectangular filter paper into a filter paper cylinder, which is placed in the outer cylinder and tightly surrounds the inner wall of the outer cylinder.

[0016] The filter paper material can be woven fabric or non-woven fabric, and a harder filter paper is preferred.

[0017] The bottom end position of the adsorption filter paper is preferably lower than the bottom end height of the filter window.

[0018] The adsorption filter paper is preferably arranged on the upper part of the inner wall of the outer cylinder.

[0019] In the present invention, the ratio of the outer diameter of the inner cylinder to the inner diameter of the outer cylinder is preferably 0.5 to 0.8:1, more preferably 0.6 to 0.7:1.

[0020] The ratio of the height from the bottom end of the inner cylinder filter window to the bottom of the inner cylinder to the inner diameter of the inner cylinder is 1 to 5:1, preferably 1.5 to 3:1.

[0021] The ratio of the height of the outer cylinder to the inner diameter of the outer cylinder is 1 to 5:1, preferably 1.2 to 3:1.

[0022] Furthermore, the present invention also provides a method for using the device for quickly separating plant cyst nematode cysts, wherein the device is used to quickly separate plant cyst nematode cysts, and the method comprises:

[0023] (1) Weigh the soil sample to be tested and put it into the inner cylinder; put the filter paper cylinder rolled up by filter paper into the outer cylinder so that the filter paper cylinder surrounds and closely adheres to the inner wall of the outer cylinder to form an adsorption filter paper;

[0024] (2) Add water to the inner cylinder until it reaches 2 / 3 to 3 / 4 of the height below the bottom of the filter window of the inner cylinder, and gently stir the mixed liquid in the inner cylinder with a glass rod for 5 to 10 times;

[0025] (3) Continue to slowly add water to the inner cylinder until the water in the inner cylinder slightly exceeds the bottom of the filter window, so that the floating objects on the surface overflow from the screen of the filter window into the outer cylinder;

[0026] (4) Continue to gently stir the inner tube with a glass rod and slowly add water. Stop adding water when there is basically no floating matter on the water surface of the inner tube.

[0027] (5) Add water to the outer tube so that the liquid level in the outer tube reaches a position above the bottom of the adsorption filter paper. Due to the surface tension of water, the cysts will be adsorbed onto the filter paper;

[0028] (6) Remove the adsorption filter paper and obtain the cysts separated from the soil sample to be tested.

[0029] In the step (1), the filter paper is preferably wetted with water before being placed in the outer cylinder, so as to facilitate the filter paper to adhere closely to the inner wall of the outer cylinder.

[0030] The shape of the filter paper is preferably rectangular, with a length slightly larger than the circumference of the inner wall of the outer cylinder and a height smaller than the height of the outer cylinder, preferably 6-8 cm, to facilitate subsequent observation under a microscope.

[0031] The adsorption filter paper is preferably placed close to the upper part of the inner wall of the outer cylinder, and the bottom end of the adsorption filter paper is preferably lower than the bottom end height of the filter window of the inner cylinder. Placing the adsorption filter paper on the upper part of the inner wall of the outer cylinder is convenient for taking and placing the filter paper, and is also convenient for observing the adsorption of cysts on the water surface. In addition, small impurities may overflow from the inner cylinder, and their density is greater than that of water, which will be deposited at the bottom of the outer cylinder. Therefore, the adsorption filter paper should not be placed near the bottom of the inner wall of the outer cylinder, otherwise it will be easily contaminated by impurities, which is not conducive to subsequent observation.

[0032] Furthermore, in step (5), water is added to the outer cylinder so that the liquid level in the outer cylinder reaches a position above the bottom of the adsorption filter paper. Preferably, water is added so that the liquid level in the outer cylinder reaches a position in the middle of the height of the adsorption filter paper, so that the cysts are just adsorbed in the middle of the filter paper, which is convenient for observation after removal.

[0033] Furthermore, in step (5), water is added to the outer cylinder, and 1-2 drops of a surfactant may be added to increase the surface tension of the water, which facilitates the diffusion of the cysts to the outer surface of the water where the filter paper is adsorbed.

[0034] The working principle of the device of the present invention is: utilizing the characteristic that the density of cysts is mostly smaller than that of water, setting a screen at the upper end of the mixed liquid, the screen can block most of the impurities larger than the cysts, allowing the floating cysts with smaller particles to pass through the screen into the outer cylinder, and then the cysts are attached to the filter paper by the surface tension of water.

[0035] The present invention provides a convenient and efficient device for quickly separating plant cyst nematode cysts and a method for quickly separating plant cyst nematode cysts, and the beneficial effects thereof are:

[0036] 1. Fast separation speed: separation of one sample takes less than 10 minutes.

[0037] 2. Low cost: The device can be made of metal, plexiglass and other materials, with low manufacturing cost and can be reused for a long time.

[0038] 3. Good separation effect: first use the sieve to filter large floating particles, and then use filter paper to adsorb the floating cysts, so that the sample to be observed is cleaner and has less impurities. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the structure of a device for rapid separation of plant cyst nematode cysts. DETAILED DESCRIPTION

[0040] The technical solution of the present invention is further described below in conjunction with embodiments, but the protection scope of the present invention is not limited thereto.

[0041] Example 1

[0042] like Figure 1 As shown, the rapid separation device of plant cyst nematode cysts consists of an outer cylinder 1 and an inner cylinder 2, the inner cylinder 2 is fixed inside the outer cylinder 1, and both the outer cylinder 1 and the inner cylinder 2 are cylindrical with an open upper end and a sealed bottom; more than one filter window 3 is arranged on the upper part of the inner cylinder 2, and the filter window 3 makes the inner cylinder 2 and the outer cylinder 1 communicate, and the filter window 3 is covered with a 18-25 mesh screen 4, and the inner wall of the outer cylinder is provided with a circle of adsorption filter paper 5 tightly surrounding the inner wall.

[0043] Further, the screen 4 can be fixed on the filter window 3, or can be detachably connected to the filter window 3. The size of the screen 4 should be larger than the size of the filter window 3, so that the screen 4 can completely cover the filter window 3.

[0044] The detachable connection between the screen 4 and the filter window 3 can be a snap-on type or a slot-on type. For example, the screen is installed in a screen frame that matches the filter window, a slot is provided at the edge of the filter window on the outer wall of the inner cylinder, and the screen frame is inserted into the slot to achieve a slot-on type detachable connection. Alternatively, holes are punched on the frame of the screen frame, corresponding bumps are provided at the edge of the filter window on the outer wall of the inner cylinder, and the holes on the screen frame are aligned with the bumps and pressed to assemble, thereby achieving a snap-on type detachable connection. There are many ways to implement this type of detachable connection, all of which are applicable to the present invention.

[0045] More preferably, the rectangular screen is rolled into a cylindrical shape, and the screen cylinder is placed in the inner cylinder. The elasticity of the screen itself is utilized to make the screen cylinder close to the inner wall of the inner cylinder, so that the screen can also cover the filter window.

[0046] The height of the screen cylinder should be greater than the height from the top of the filter window to the bottom of the inner cylinder. The length of the screen cylinder is greater than the circumference of the inner wall of the inner cylinder.

[0047] The filter window 3 can be in various shapes, and preferably the bottom of the window is a straight line parallel to the bottom of the cylinder, and more preferably a rectangle.

[0048] Figure 1 That is, two rectangular filter windows are provided. When there are more than two filter windows 3, the bottom ends of the filter windows 3 should be at the same height of the inner cylinder, and filter windows of different heights should not be provided.

[0049] The bottom end of the filter window 3 is preferably lower than the top end of the outer cylinder 1 .

[0050] The adsorption filter paper 5 on the inner wall of the outer cylinder can be formed by rolling a rectangular filter paper into a filter paper cylinder, which is placed in the outer cylinder and tightly surrounds the inner wall of the outer cylinder.

[0051] The filter paper material can be woven fabric or non-woven fabric, and a harder filter paper is preferred.

[0052] The bottom end position of the adsorption filter paper 5 is arranged below the bottom end height of the filter window 3 .

[0053] The adsorption filter paper 5 is preferably arranged on the upper part of the inner wall of the outer cylinder 1 .

[0054] The ratio of the height from the bottom end of the inner cylinder filter window to the bottom of the inner cylinder to the inner diameter of the inner cylinder is 1 to 5:1, preferably 1.5 to 3:1.

[0055] The ratio of the height of the outer cylinder to the inner diameter of the outer cylinder is preferably 1 to 5:1, preferably 1.2 to 3:1.

[0056] Example 2

[0057] The device of Example 2 is used to quickly separate plant cyst nematodes, and the steps are as follows:

[0058] 1. Weigh the soil sample to be tested and put it into the inner cylinder; put the filter paper cylinder rolled up by filter paper into the outer cylinder, wet the filter paper with water first, so that the filter paper cylinder surrounds and sticks to the inner wall of the outer cylinder to form an adsorption filter paper;

[0059] 2. Add water to the inner cylinder until it is 2 / 3 to 3 / 4 of the height below the bottom of the filter window of the inner cylinder, and gently stir the mixed liquid in the inner cylinder with a glass rod for 5-10 times;

[0060] 3. Continue to slowly add water to the inner cylinder, so that the water in the inner cylinder slightly exceeds the bottom of the filter window, so that the floating objects on the surface overflow from the screen of the filter window into the outer cylinder;

[0061] 4. Continue to gently stir the inner tube with the glass rod and slowly add water. Stop adding water when there is basically no floating matter on the water surface of the inner tube.

[0062] 5. Add water to the outer cylinder so that the liquid level in the outer cylinder reaches the middle of the height of the adsorption filter paper. Due to the surface tension of water, the cysts will be adsorbed onto the filter paper;

[0063] 6. Remove the adsorption filter paper and obtain the cysts separated from the soil sample to be tested.

[0064] The filter paper is rectangular, with a length slightly larger than the circumference of the inner wall of the outer cylinder and a height smaller than the height of the outer cylinder, preferably 6-8 cm, to facilitate subsequent observation under a microscope.

[0065] The adsorption filter paper is preferably attached to the upper part of the inner wall of the outer cylinder, and the bottom end of the adsorption filter paper is preferably lower than the bottom end height of the filter window of the inner cylinder. Figure 1 As shown, the adsorption filter paper 5 is arranged on the upper edge of the inner wall of the outer cylinder 1 , and the bottom end thereof is lower than the bottom end height of the filter window 3 .

[0066] In the step (5), 1-2 drops of surfactant may be added to increase the surface tension of water, thereby facilitating the diffusion of spores to the area outside the water surface adsorbed by the filter paper.

[0067] Example 3

[0068] In this embodiment, the size of the device is specifically limited, but the protection scope of the present invention is not limited thereto.

[0069] The inner diameter of the inner cylinder is 6.6cm, the outer diameter is 7cm, the inner diameter of the outer cylinder is 10cm, and the inner and outer cylinders are on the same central axis. The inner cylinder is provided with two rectangular filter windows, the height from the lower end of the filter window to the bottom of the cylinder is 12cm, the filter window height is 6cm, and the height of the outer cylinder is 18cm.

[0070] A filter paper cylinder is arranged on the inner wall of the outer cylinder, which is tightly fitted around the outer cylinder and serves as the filter paper. The filter paper cylinder is 8 cm high and 32 cm long.

[0071] This device can separate plant cyst nematode cysts from 50g of soil sample to be tested.

Claims

1. A rapid separation device for plant cyst nematode cysts, characterized in that The device consists of an outer cylinder and an inner cylinder, the inner cylinder is fixed inside the outer cylinder, and both the outer cylinder and the inner cylinder are cylindrical with an open upper end and a sealed bottom; one or more filter windows are arranged on the upper part of the inner cylinder, the filter windows make the inner cylinder and the outer cylinder communicate, the filter windows are covered with a 18-25 mesh screen, the inner wall of the outer cylinder is provided with a circle of adsorption filter paper tightly surrounding the inner wall; the bottom end position of the adsorption filter paper is lower than the bottom end height of the filter window; the adsorption filter paper is arranged on the upper part of the inner wall of the outer cylinder.

2. The device according to claim 1, characterized in that The screen is fixed on the filter window, or the screen is detachably connected to the filter window.

3. The device according to claim 2, characterized in that The screen is obtained by rolling a rectangular screen into a cylindrical shape, placing the screen cylinder into an inner cylinder and clinging to the inner wall of the inner cylinder.

4. The device according to claim 3, characterized in that The height of the screen cylinder is greater than the height from the top of the filter window to the bottom of the inner cylinder.

5. The device according to claim 1, characterized in that When there are more than two filter windows, the bottom ends of the filter windows are at the same height of the inner cylinder.

6. The device according to claim 1, characterized in that The adsorption filter paper on the inner wall of the outer cylinder is formed by rolling a rectangular filter paper into a filter paper cylinder, which is placed in the outer cylinder and tightly surrounds the inner wall of the outer cylinder.

7. A method for rapidly separating plant cyst nematode cysts using the device according to any one of claims 1 to 6, the method comprising the following steps: (1) Weigh the soil sample to be tested and put it into the inner cylinder; put the filter paper cylinder rolled up by filter paper into the outer cylinder so that the filter paper cylinder surrounds and closely adheres to the inner wall of the outer cylinder to form an adsorption filter paper; (2) Add water to the inner cylinder until it reaches 2 / 3 to 3 / 4 of the height below the bottom of the filter window of the inner cylinder, and gently stir the mixed liquid in the inner cylinder with a glass rod for 5 to 10 times; (3) Continue to slowly add water to the inner cylinder until the water in the inner cylinder slightly exceeds the bottom of the filter window, so that the floating objects on the surface overflow from the screen of the filter window into the outer cylinder; (4) Continue to gently stir the inner tube with a glass rod and slowly add water. Stop adding water when there is basically no floating matter on the water surface of the inner tube. (5) Add water to the outer tube so that the liquid level in the outer tube reaches a position above the bottom of the adsorption filter paper, and the cysts will be adsorbed onto the filter paper; (6) Remove the adsorption filter paper and obtain the cysts separated from the soil sample to be tested.

8. The method according to claim 7, characterized in that In the step (5), water is added to the outer cylinder so that the liquid level in the outer cylinder reaches a position in the middle of the height of the adsorption filter paper.

9. The method according to claim 7, characterized in that In the step (5), water is added to the outer cylinder, and 1-2 drops of a surfactant are added at the same time.

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