Agricultural insect-proof net

Abstract

To prevent, with high probability, the entry of hard-to-control minute pests such as whiteflies into, in particular, an agricultural house.SOLUTION: In an agricultural insect-proof net in which warps and wefts made of monofilament are woven to have a mesh size of 0.4 mm or less, both the warps and the wefts are colored black, thereby preventing attraction of pests, suppressing activation of pest activity, and preventing intrusion of pests.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an agricultural insect-proof net for preventing pests from entering an agricultural greenhouse, particularly in the cultivation of vegetables, flowers, and the like.

Background Art

[0002] An agricultural insect-proof net used by covering plants is formed by weaving synthetic resin monofilaments such as polyethylene into a lattice using warp and weft threads, and the mesh size varies depending on the target pests. For example, for controlling diamondback moths, aphids, cabbage white butterflies, and noctuid moths, an insect-proof net with a mesh size of 1.0 mm is used, and for aphids, an insect-proof net with a mesh size of 0.8 mm is used. The mesh size suitable for leafminer flies and greenhouse whiteflies is finer, 0.6 mm, and for whiteflies and thrips, it is 0.4 mm.

[0003] Since the monofilaments constituting such an insect-proof net are for preventing the invasion of pests, they are generally made of transparent materials that are difficult to block light.

[0004] However, reducing the mesh size can control more types of pests, but on the other hand, there is a risk of inhibiting air permeability. In that case, even if pest control can be achieved, it will inhibit the growth of plants, which is not preferable.

[0005] Therefore, the applicant proposed an insect-proof net made of red monofilaments as described in Patent Document 1 below. This red insect-proof net has a mesh size of 0.8 mm, but since red is a color that is not visible to pests, it has a better invasion prevention effect against thrips such as onion thrips compared to an insect-proof net made of transparent monofilaments.

[0006] However, particularly in an agricultural greenhouse where the temperature is high and pest activity is likely to be active, the invasion prevention rate may sometimes decrease.

Prior Art Documents

Patent Document

[0007]

Patent Document 1

Non-Patent Document

[0008]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] The main problem of this invention is to obtain high control efficiency against troublesome and difficult-to-control minute pests that transmit diseases through viruses, especially whiteflies.

Means for Solving the Problems

[0010] Therefore, this invention provides the following agricultural insect-proof net. The agricultural insect-proof net is woven from monofilament warp and weft threads with a mesh size of 0.4 mm or less, and both the warp and weft threads are black or the complementary color of yellow.

[0011] In this configuration, the warp and weft threads that exhibit black or the complementary color of yellow absorb light of colors including yellow. That is, it prevents the agricultural insect-proof net from reflecting yellow light and appearing yellow. For this reason, pests such as whiteflies that are attracted to yellow (see Non-Patent Document 1) are not attracted unnecessarily, and intrusion is prevented by the mesh size.

Effects of the Invention

[0012] According to the present invention, the fine mesh and the colors of the warp and weft threads prevent the insect-proof net from appearing yellow more reliably. Thus, the invasion of pests is prevented without attracting the pests. That is, the invasion can be prevented by suppressing the activation of the activities of the pests. Therefore, the invasion prevention effect is high, and the invasion prevention can be achieved even when used inside an agricultural greenhouse at a temperature at which the activities of the pests tend to become active. In this way, high insect-proof performance against difficult-to-control minute pests can be obtained.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0014] One embodiment for carrying out the present invention will be described below with reference to the drawings.

[0015] FIG. 1 is a surface view showing an enlarged view of an agricultural insect-proof net 11 (hereinafter also referred to as an "insect-proof net"). The insect-proof net 11 is formed in a sheet shape by weaving warp threads 12 and weft threads 13 at equal intervals. Thin monofilaments made of a synthetic resin such as polyethylene are used for the warp threads 12 and the weft threads 13. The fineness thereof is 145 dtex. The color of the filament is a complementary color (violet-blue, blue) of yellow or a similar color, or black so that the insect-proof net 11 does not look yellow. More preferably, black monofilaments may be used. This is because it absorbs light of all wavelengths and is good in terms of the manufacturing cost of the filaments.

[0016] The mesh of the insect-proof net 11 is square, and the mesh size is 0.4 mm. Specifically, both the vertical a and the horizontal b of the mesh are formed to be 0.4 mm. The size of the mesh may be formed smaller than that, or the lengths of the vertical and horizontal may be different. That is, at least one of the vertical a and the horizontal b may be smaller than 0.4 mm.

[0017] The insect-proof net 11 formed by weaving a monofilament made of the complementary color of yellow or its similar color, or black, will exhibit a black or blackish color as a whole.

[0018] The insect-proof net 11 is formed in a long strip shape with an appropriate width such as 1.35 m, 1.8 m, 2.1 m, etc., wound into a roll and circulated. It can also be cut into a predetermined size, folded, and used for circulation. Lines of a color different from that of the warp 12 and the weft 13 may be woven in a lattice pattern along the warp 12 and the weft 13, or in place of the warp 12 and the weft 13, so as to serve as a guide for the longitudinal and transverse lengths of the insect-proof net 11.

[0019] Such an insect-proof net 11 is used by stretching it over openings such as skylights, side windows, ventilation openings, and entrance / exit doors in agricultural greenhouses such as vinyl greenhouses and glass greenhouses, where it is desired to prevent the intrusion of pests. In addition, it may be used to cover the plants to be protected by smearing or tunnel covering.

[0020] A test was conducted to examine the insect-proof effect of the insect-proof net 11.

[0021] As shown in FIG. 2, the test was carried out using a rectangular parallelepiped-shaped box 21 with four open sides. One group had the sides blocked with the insect-proof net 22 and the other group did not, and the number of pests invading the interior was compared. As shown in FIG. 3, the box 21 was installed around the plant 32 being cultivated in a planter inside the agricultural greenhouse 31, and the number of invading pests was counted over a certain period. The plant was kansho. When installing the box 21, its height was placed on a stand and adjusted to match the height of the plant.

[0022] The box 21 used in the test had an outer dimension of 30 cm in length and width and 43 cm in height, and an insect-catching paper 23 was suspended inside. The insect-catching paper 23 used was "Horiba (registered trademark) Yellow" manufactured by Alice Life Science Co., Ltd. As the name of the product indicates, it is yellow in color. The size of the insect-catching paper 23 was 257 mm in length and 100 mm in width.

[0023] The insect-proof net 22 had a mesh size of 0.4 mm and was made of black polyethylene monofilaments for both the warp and weft threads.

[0024] As a comparative example, boxes 21 covered with insect-proof nets 22 of other colors were also prepared. The insect-proof net 22 was composed of transparent monofilaments for both the warp and weft threads, and the warp thread was made of a red monofilament and the weft thread was made of a black monofilament. The box covered with the insect-proof net 22 consisting of black monofilaments for both the warp and weft will be referred to as "black-black". Also, the box covered with the insect-proof net 22 using transparent monofilaments for both the warp and weft threads will be called "white-white", and the box covered with the insect-proof net 22 using a red monofilament for the warp and a black monofilament for the weft will be referred to as "red-black".

[0025] A total of four boxes, three boxes 21 covered with the insect-proof net 22 and one box 21 without the insect-proof net 22, were evenly arranged around the plant 32, and the number of thrips captured on the sticky paper every day was counted for one week. The daily counting was carried out for one week, and the installation position was shifted to the adjacent one every week, and the counting of the captured pests was carried out over eight weeks. After the counting, all the pests in the box 21 were removed and returned to the initial state each time.

[0026] The results are as shown in Table 1. Among the test plots in the left column of the table, "untreated" refers to the box 21 without the insect-proof net 22.

[0027]

Table 1

[0028] As is clear from this table, in the untreated test plot, the number of thrips captured is much larger by an order of magnitude compared to the other test plots, with more than 100 thrips invading every day and exceeding 1000 on some days. This is also related to the fact that the sticky paper is yellow and has an attracting effect.

[0029] In contrast, in the test plot "white - white", the average number per day was 6.8 heads from the first week to the eighth week, indicating that compared with the "untreated" plot, it is obvious that intrusion prevention is much more effective. In the test plot "red - black", the number of captured pests per day is even fewer, at 1.63 heads. Even in the weeks with a relatively large number, it is only a few heads per day, and a good intrusion prevention effect is recognized. In the test plot "black - black", there were three weeks when the number of captured pests per day was 0 heads, and even in the week with the largest number, the number of captured pests per day was 1.25 heads. The average number of captured pests per day over the entire week was 0.45 heads, indicating that a very high intrusion prevention effect can be obtained. Moreover, although there is a yellow object (insect - catching paper 23) inside box 21 that has an attracting effect on pests, intrusion can be prevented, so it can be said that the intrusion prevention effect is high.

[0030] As can be seen from the above test results, the insect - proof net 11 with a mesh size of 0.4 mm using black monofilaments for the warp 12 and weft 13 has a high intrusion prevention rate for thrips. Since the insect - proof net 11 using black monofilaments can prevent the intrusion of pests, it is assumed that an insect - proof net 11 made of monofilaments that absorb yellow light and present the complementary color of yellow or a similar color thereof will also have a high intrusion prevention rate for pests.

Explanation of reference numerals

[0031] 11… Insect - proof net for agriculture 12… Warp 13… Weft

Claims

1. An agricultural insect-proof net woven from warp and weft made of monofilaments with a mesh size of 0.4 mm or less, wherein both the warp and weft are black or are a complementary color to yellow agricultural insect-proof net.

2. An agricultural insect-proof net attached to an opening of an agricultural house, composed of warp and weft made of monofilaments that are black or are a complementary color to yellow, and with a mesh size formed to be 0.4 mm or less agricultural insect-proof net.

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