JPH0258898B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a synthetic resin film for pest control, and more specifically, for growing and growing useful plants.
The present invention relates to a synthetic resin film for pest control that is effective for controlling various pests that fly to and parasitize plants during cultivation. BACKGROUND ART Conventionally, when useful plants such as vegetables, flowers, and grains are cultivated, various pests fly to the cultivated plants, become parasitic, and feed on them, resulting in great damage. Many agricultural chemicals (insecticides) have been developed and put into practical use for the purpose of controlling these pests. However, by continuing to use these pesticides, insect pests become more resistant over time, and their insecticidal effectiveness decreases over time. For this reason, pesticides with stronger insecticidal effects are being developed and used. As the bactericidal effects of these pesticides are strengthened,
The toxicity to human stock increases, and at the same time, more substances accumulate in the soil, which may cause secondary pollution such as environmental pollution, which poses problems. In order to solve such problems, clean pest control methods are being researched and attracting attention. Clean pest control methods include methods that use natural enemies of pests, methods that use pheromones and moth-attracting lights that attract pests, and trap them with traps, etc., and some of these methods have been put to practical use. However, these methods also have various problems. For example, methods that use natural enemies of pests do not cause the environmental pollution problems that occur when using conventional pesticides (insecticides), but they do have the problem of altering the natural animal ecosystem, so caution should be taken. It is necessary to respond to Furthermore, methods of trapping using pheromones or moth-attracting lights have the problem of cost. As a measure to solve the above problems, JP-A-52-
As described in Publication No. 61581, a method was proposed to suppress the flying of pests by covering the soil for cultivating useful plants with a highly reflective film.
It has come to be put into practical use. A method that has been put into practical use is to cover the ridges with a synthetic resin film on which a metal such as aluminum is vapor-deposited. However, this method also has the following problems. In other words, metal vapor-deposited films such as aluminum used for covering ridges have high product costs, and while the film surface has a high light reflectance, the light transmittance is low, so the light rays do not reach the soil and the soil temperature does not rise. . Preventing soil temperature from rising is favorable for suppressing the cultivation of useful plants in the summer, but in many cases,
It has a negative effect on the growth of cultivated plants. Under such circumstances, the present inventors have conducted extensive studies with the aim of increasing the soil temperature of the soil for cultivating useful plants to promote plant growth and to suppress the arrival of pests that parasitize these cultivated plants. result,
The present invention has now been completed. However, the gist of the present invention is to provide a synthetic resin film for pest control with a wavelength of 500 to 500.
Spectral specific reflectance of rays in the range of 560nm is 40%
The present invention relates to a red synthetic resin film for pest control, which is as follows, and has a spectral reflectance of visible light having a wavelength of 650 nm or more that is adjusted to 70% or more. The present invention will be explained in detail below. The synthetic resin film for controlling pests according to the present invention includes:
Made of flexible synthetic resin film. Flexible synthetic resin films include soft blended polyvinyl chloride,
Examples include films made of polyethylene, polypropylene, ethylene-vinyl acetate copolymers, polyamides, polyesters, and the like. The flexible synthetic resin film is not limited to those exemplified above. These synthetic resin films may contain various resin additives such as heat stabilizers, lubricants, antioxidants, ultraviolet absorbers, fillers, etc., in types and amounts that do not impede the purpose of the present invention. There are no particular restrictions on the method for producing the film, and it can be produced by conventionally known methods such as T-die extrusion, inflation molding, calendar molding, and solution casting. The thickness of the synthetic resin film is not particularly limited, but is preferably in the range of several microns to 500 microns. The width of the synthetic resin film can be appropriately selected from a range of several tens of cm to several meters. The synthetic resin film for controlling pests according to the present invention includes:
The spectral reflectance of light in the wavelength range of 500 to 560 nm is 40% or less, and the spectral reflectance of visible light with a wavelength of 600 nm or more is adjusted to 70% or more, and is colored red. Must be. Pests such as honey beetles, aphids, and whiteflies have the property of avoiding visible ultraviolet rays that are highly reflected (see Japanese Patent Application Laid-open No. 52-61581). The present inventors have discovered that there is an attractive effect. Therefore, the proportion of reflected light in the wavelength range of 500 to 560 nm is kept as low as possible, and
If we increase the rate of reflection of light rays outside the range as high as possible, objects with such light reflection characteristics will have
Pests will no longer be able to approach you. According to experiments conducted by the inventors, the spectral reflectance of light in the wavelength range of 500 to 560 nm is 40% or less, and
Spectral ratio reflectance of visible light above 650nm is 70
% or more was particularly preferable. In order to impart the above-mentioned light reflection characteristics to a synthetic resin film, a red dye and pigment is blended to form a colored film. When the film is colored red, the film becomes less effective at attracting the pests (increases the film's ability to repel pests), and at the same time, it emits red light that activates the photosynthetic reactions of cultivated plants.
It is selectively reflected on the leaves of cultivated plants. In order to impart the above-mentioned light reflection characteristics to a synthetic resin film, it is preferable to blend and mix a red coloring agent with the base synthetic resin when producing the synthetic resin film. Examples of the red coloring agent used to achieve the object of the present invention include the following, but it goes without saying that the coloring agent is not limited to the exemplified ones. Standard Name CI Number Paralleled 12070 Permanent Red FRR 12310 Lake Red 4R 12120 Permanent Red R 12085 Brilliant First Scarlet 12315 Pyrazolone Red B 21120 Lake Red C 15585 Brilliant Carmine 6B 15850 Valve Pattern − Congo Red D/R26 Dispersed Red R D /R17 Solvent Red 152 Solvent Red 176 Solvent Red 155 Solvent Red 177 Solvent Orange 71 The amount of these colorants added to the base synthetic resin may be selected so that the light reflection properties of the film fall within the above range. The amount can be selected depending on the type of synthetic resin, the type of colorant, the film manufacturing method, manufacturing conditions, film thickness, etc., but it is selected in the range of 0.01 to 2 parts by weight per 100 parts by weight of synthetic resin. be able to. In order to bring the light reflection characteristics of the film into the above range, a metal is vapor-deposited on one side of the red-colored synthetic resin film, or a paint containing metal foil is applied by roll coating, spray coating, etc. It is possible to adopt a method such as coating by a method, or a method of laminating a separately prepared metal vapor deposited film. Metals used for metal vapor deposition and metal foil formation include aluminum, chromium, nickel, selenium, germanium, etc., but aluminum is preferred from the viewpoint of durability and economy. The synthetic resin film for controlling pests according to the present invention includes:
The spectral reflectance of the light beam needs to be adjusted within the above range. In the present invention, the "spectral specific reflectance" of a light beam means a value measured in accordance with condition (3) of JIS Z8722-1972 Method for Measuring Reflective Objects. In order to cultivate useful plants using the synthetic resin film for pest control according to the present invention, first, the ground for cultivating useful plants in open ground or in a greenhouse is tilled and ridged, and part or all of the ridges are cultivated. or part or all of the non-ridged portion is coated with the surface of the film according to the invention to which the metal foil or the like is attached facing upward. When the ridges are covered, holes of an appropriate diameter are made at appropriate intervals, and seeds are sown or seedlings are planted in the ridges through the holes. Then, the plants may be cultivated according to the usual cultivation method for sown or transplanted plants. If the ridges are not covered, it is best to install it only around the field or between the ridges. The synthetic resin film for controlling pests according to the present invention includes:
It produces the following particularly remarkable effects, and its industrial utility value is extremely great. (1) The synthetic resin film for pest control according to the present invention has a wavelength of 500 to 560 nm that easily attracts pests.
It has a low spectral reflectance for light in the range of , and a high spectral reflectance for visible light with a wavelength of 650 nm or more that is repelled by pests, so it can prevent pests from flying or crawling towards you. (2) The synthetic resin film for controlling pests according to the present invention can suppress the flying and crawling of pests without covering the entire surface of the ground for cultivating useful plants. It does not have a negative effect on the growth of plants. (3) Since the synthetic resin film for pest control according to the present invention is colored red, it selectively reflects on the leaf surfaces of cultivated plants, and as a result, the growth of crops is promoted. Hereinafter, the present invention will be explained in detail based on examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. Examples 1 to 3, Comparative Examples 1 to 3 <Production of film> Polyethylene (manufactured by Mitsubishi Yuka Co., Ltd., Yucalon YK-
30) and Permanent Red R in the proportions shown in Table 1, and the resin and colorant were mixed uniformly with a tumbler mixer. This mixture was kneaded using an extruder and extruded into tubes from an inflation die to produce six types of films each having a thickness of 50 microns. Aluminum was deposited on each film by a conventional method to form a reddish reflective film with a thickness of 300 Å on one side. The spectral specific reflectance of the six types of films was measured using a spectrophotometer (manufactured by Hitachi, Model 323) in accordance with condition (3) of JIS Z8722-1972 Method for Measuring Reflective Objects. The results are shown in Table 1. <Pest control test-1> A pest control test was conducted on the above six types of films as follows. An orchard cultivated by Natsudai Kawano for 10 years, since the Showa era.
On April 15, 1957, each film was laid on the ground. The film is laid over the entire area under the tree canopy without any gaps.
There were 8 trees per kind of film. The distance between different films (each test section) was 4 to 5 meters. On July 8, 1982, before fruit thinning, 30 fruits were randomly extracted from each tree, and the degree of damage to the fruits caused by the Koa-o-namuri, which visited the flowers during cultivation, was visually observed. The results are shown in Table 1 as a fruit damage index. The fruit damage index indicates the degree of damage as none, light, or
It was divided into five categories: medium, severe, and severe, and was calculated based on the formula below. Fruit damage index = [(Number of light) x 1] + [(Number of medium) x 3] + [(Number of severe) x 5] + [(Number of severe) x 7
]/Number of research fruits x 7

[Table] In addition, in a test of the degree of damage to the fruit of Kawano summer daisies caused by the Koaohanamuri, the damage index of the fruit in the bare area where no film was used was observed and calculated in the same manner as above, and it was 28.8. . From Table 1, it is clear that the synthetic resin film for pest control according to the present invention has a remarkable pest control effect. The films of Comparative Examples 1 and 2 were
Since the value of the spectral specific reflectance in the wavelength range of 500 to 560 nm exceeds 40%, the damage index of the fruit is large, and the film of Comparative Example 3 is
Since the value of spectral specific reflectance at 650 nm is less than 70%, the fruit damage index is also high. <Pest control test-2> Separately from the above test, a pest control test was conducted by laying a film only on the ground around the orchard. The film of Example 2 and a commercially available aluminum vapor-deposited polyethylene film (manufactured by Reiko Co., Ltd.,
A film with a width of 1 m was laid around a 15 m x 17 m plot in the Kawano Natsudai Orchard, and the same method as in the above test was used to measure the amount of fruit per tree. Approximately 40 fruits were extracted, and the damaged fruits caused by Koa-o-na-muri were observed, and the damage index of the fruits was calculated. The results were as shown in Table 2 below.

[Table] Table 2 shows that the synthetic resin film for pest control according to the present invention can sufficiently exert its pest control effect even when it is laid around the four circumferences of the cultivation field, instead of being laid all over the cultivation field. It shows. <Flower-visiting activities of honeybees> During the above test period (late May 1981), flower-visiting activities of bees, which are pollinating insects, were observed. Bees were observed visiting the flowers of the summer daisies in all test sections, and no significant difference was observed between them and the bare plots. Examples 4 to 6, Comparative Examples 4 to 6 <Production of film> A soft polyvinyl chloride formulation consisting of the combination of raw materials and auxiliary agents listed in Table 3 was kneaded by a conventional method, and molded to a thickness of 50 mm by a calender molding method. micron 6
A seed film was produced. On one side of each film, a film in which aluminum was vapor-deposited to a thickness of 300 Å on a polyester film having a thickness of 30 microns was laminated using a urethane adhesive. The spectral specific reflectance of the six types of films obtained was measured in the same manner as in the previous example. The results are shown in Table 3. <Pest control test> Add 3-10-10 compound fertilizer to soil, 100g/
Fertilize with m ² and till, row width 70cm, row spacing 5
We made seven ridges with a height of 10 cm and a length of 11 m.
Each ridge was covered with one film of the above six types with a width of 90 cm (one ridge was left bare without being covered with a film), and the edge of the film was buried in soil. Next, approximately the center of each ridge, place a 5cm diameter
A single line of holes was drilled at 50 cm intervals. On May 14, 1981, soybean (triangle) was sown into the hole. On June 22, 1981,
Ten soybean plants were removed from the center of each test plot, and each plant was placed in a polyethylene bag. After the bag was left sealed for one day, the number of pests that had fallen into the polyethylene bag, as well as the pests that were attached to the leaves, stems, etc., were scraped off with a paintbrush dipped in ethanol. The number of insect pests per plant was counted, and the average number of pests per plant was calculated. The results are shown in Table 3. The parasitic pests included soybean aphid, bean aphid, and zelkova aphid.

[Table] From Table 3, it is clear that the synthetic resin film for controlling pests according to the present invention has a lower number of pests infesting it than the film of the comparative example, and is therefore more effective in controlling pests. Become.

Claims (1)

[Claims] 1. In a synthetic resin film for pest control, the spectral reflectance of light in the wavelength range of 500 to 560 nm is 40% or less, and the spectral reflectance of visible light with a wavelength of 650 nm or more is adjusted to 70% or more. A red-colored synthetic resin film for pest control, which is characterized by the fact that: