JPS6411251B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel agricultural covering material, and more particularly, it is made of a blue-colored UV-shielding synthetic resin material having specific light transmission properties, and is particularly suitable for agricultural cultivation of fruit and vegetable plants. Relating to coating materials. Several agricultural covering materials with UV-shielding properties have been proposed. For example, JP 48-37459, JP 49-16301, JP 53-47383.
See Japanese Patent Application Laid-open No. 100445/1983, etc. On the other hand,
For a long time, various studies have been conducted on the relationship between light in the visible light range and plant growth. For example, Japanese Patent Publication No. 27-2911, Japanese Patent Publication No. 47-24376,
Special Publication No. 49-17093, Publication No. 49-43778, Comprehensive research on technologicalization of light quality utilization in facility agriculture: Published by the Agriculture, Forestry and Fisheries Technology Council Secretariat (1972)
(Published on February 29, 2016) See pages 88-89, etc. Furthermore, some agricultural films have been proposed that block ultraviolet rays and are also colored in a specific color. For example, see Japanese Patent Publication No. 54-15818, Japanese Unexamined Patent Publication No. 52-43637, Report of the Agricultural and Electrical Research Institute of the Central Research Institute of Electric Power Industry: Research Report: 71003 (October 1972), p. 18. However, although these conventionally proposed colored ultraviolet-shielding agricultural films can be expected to have a certain degree of improvement in promoting the growth of cultivated plants and increasing yield, they are still not sufficient. The present inventors have also focused on UV-shielding agricultural covering materials, and found that UV-shielding agricultural covering materials can inhibit the propagation of pathogenic bacteria on plants, prevent tearing of tomato fruits, increase the sugar content of fruits, and increase the sugar content of leaves. We have previously proposed this method after discovering that it has excellent effects on preventing rot in stem vegetables, preventing aging in green peppers, and preventing aging in cucumbers. For example, JP-A-53-47383, JP-A-52-98125, JP-A-53-2238, JP-A-53-27539, JP-A-53-75039,
See JP-A-53-117546, JP-A-53-127126, JP-A-53-127129, etc. Furthermore, regarding colored UV-blocking agricultural covering materials,
The present inventors disclosed in Japanese Patent Application Laid-Open No. 117738/1983 that the average transmittance for visible light in the wavelength range of 400 to 700 nm is at least 40%, and that
The ratio of the average transmittance to blue light with a wavelength of 500 nm to the average transmittance to red light with a wavelength of 600 to 700 nm is in the range of 1.2:1 to 2.5:1,
In addition, we have proposed a blue-colored ultraviolet-shielding agricultural covering material made of an agricultural synthetic resin film or plate that has the property of substantially blocking light rays with wavelengths of at least 370 nm and below. However, this UV-shielding agricultural covering material was developed specifically for raising rice seedlings, and has a fairly low transmittance for light in the red wavelength region, making it difficult to use when used in the facility cultivation of fruit and leafy vegetables. However, the disadvantage is that sufficient growth promotion and yield increase effects cannot be expected. Therefore, the present inventors conducted extensive research on colored ultraviolet-shielding agricultural covering materials suitable for growing fruit vegetables and leafy vegetables, especially fruit plants.
Agricultural coverings having the following light transmission properties: (a) substantially blocking the transmission of light with a wavelength of at least 370 nm or less, and (b) having an absorption maximum in the wavelength range of 440 nm to 700 nm between 590 and (c) the average transmittance of light with a wavelength between 440 and 590 nm is at least 85%; (d) (e) the average transmittance of light of wavelengths between 600 and 700 nm is at least 75%; and (e) the average transmittance of light of wavelengths between 400 and 500 nm is
Agricultural covering materials consisting of transparent synthetic resin films or plates colored in a blue color, with an average transmittance ratio of light with wavelengths between 600 and 700 nm of less than 1.2, are extremely suitable for growing fruit and vegetable plants. The present invention was completed based on this discovery. According to the present invention, the above (a), (b), (c),
Agricultural covering material suitable for cultivating fruit and vegetable plants, characterized by being made of a blue-colored transparent synthetic resin film or board that satisfies the five light transmission characteristics of (d) and (e). is provided. When the agricultural covering material provided by the present invention is used as a covering material for greenhouses and tunnels in the facility cultivation of fruit and vegetable plants, (a) it prevents the fatigue phenomenon during harvesting of fruit and vegetable plants; It can be effectively prevented, and the effect is particularly great in cucumbers, tomatoes, green beans, green peppers, etc. (effect of preventing fatigue). (b) The yield of fruit and vegetable plants can be significantly increased (yield increase effect). (c) It is possible to improve the quality of fruits and vegetable crops. For example, in the case of tomatoes, the incidence of fruit splitting can be reduced, and in cucumbers, the fruit color can be improved (quality improvement effect). (d) The growth of the plant height of fruit and vegetable plants is moderately suppressed,
The internodes are short, allowing you to grow tall, full-bodied plants (fulfilling cultivation effect). These cultivation effects can be obtained, and the contribution to the cultivation of fruit and vegetable plants is extremely large. In this specification, the "fatigue" phenomenon refers to, for example, "Vegetable Production Problems and Solutions" (Part 2) One Type of Technology Edition - [Seibundo Shinkosha Co., Ltd., August 25, 1978, Vol. As described in lines 10 to 20 on page 12 of [edition], in the cultivation of fruit and vegetable plants, when the fruit harvest period is over, the assimilation ability decreases due to insufficient accumulation of nutrients and aging of leaves. This refers to a phenomenon in which the yield of fruit is temporarily reduced and the quality of the fruit is often poor due to such factors. As used herein, the term "substantially blocking the transmission of light having a wavelength of xnm or less" means xnm
Not only does it completely block 100% of the transmission of light with the following wavelengths, but it also covers at least 80%, preferably 90% or more, and more preferably 95% or more of the transmission of xnm or shorter wavelengths. It is also used in the sense that it also includes. Moreover, "absorption maximum" refers to a portion of an absorption curve of an absorption spectrum that exhibits the maximum absorbance or extinction coefficient within a certain wavelength range. Note that when the top of the peak indicating the absorption maximum is substantially flat, the center point of the flat portion is referred to as the absorption maximum. Furthermore, "average transmittance" refers to the wavelength range (a to b) in a curve [f(x)] of light wavelength (horizontal axis: x axis) versus light transmittance (vertical axis). In nm, it refers to the value expressed as ∫ ^b / _a f (x) dx (%) / (ba). Therefore, the agricultural covering material that can be preferably used in the present invention satisfies the light transmission properties shown in (a), (b), (c), (d), and (e) above, and furthermore, the following ( a′), (b′),
Any one of the requirements selected from (c') and (d')
It satisfies more than one requirement at the same time. (a') Substantially blocking the transmission of light having a wavelength of at least 380 nm or less; (b') The absorption maximum in the wavelength range from 440 nm to 700 nm is 590 to 625 nm, more preferably
Between 595 and 620 nm, and the light transmittance at the absorption maximum is 70 to 88%, more preferably 75 to 85%.
be within the range of (c') The average transmittance of light with wavelengths between 440 and 590 nm is at least 85%, more advantageously 87%. and (d') the average transmittance of light with a wavelength between 600 and 700 nm is at least 75% or more, more preferably 77 to 88
Must be within the range of %. In addition, the agricultural covering material of the present invention has the following characteristics when a light wavelength (horizontal axis) versus light transmittance (vertical axis) curve is drawn.
It is preferable to have a light transmittance characteristic in which the curve rises as vertically as possible within the light wavelength range of 380nm to 420nm, especially 400nm.
About 15~80% of light with a wavelength of m is transmitted, and 400~
It is desirable that the average transmittance at 440 nm is generally in the range of 65 to 90%, preferably 70 to 85%. Furthermore, the agricultural coating material of the present invention has a wavelength from 440 nm to
There is no absorption peak in the wavelength range up to 590 nm, and in particular, the transmittance in the wavelength range from 440 nm to 525 nm can be 85% or more. but,
On the other hand, within the wavelength range from 600nm to 700nm,
In addition to the absorption peak giving the absorption maximum, weaker absorption peaks may be present, such weaker absorption peaks can exist between 660 and 700 nm, and therefore the average between 625 and 700 nm Transmission can generally be in the range 75-90%, preferably 78-87%. In addition, as the agricultural covering material of the present invention, 500~
It is desirable that the average transmittance of light with wavelengths between 600 nm and 600 nm is within the range of 0.8 to 1.1 times the average transmittance of visible light with wavelengths of 600 nm or more. There is no particular restriction on the wavelength region of 700 nm or more, but in general, the wavelength region of 700 nm or more,
In particular, the average transmittance in the infrared region is 95% or less and 60%
It is desirable that the above is achieved. Agricultural covering materials having the above-mentioned light transmitting properties can be produced, for example, by blending dyes or pigments and ultraviolet absorbers described below with ordinary film-forming synthetic resins and forming them into films or plates, or by forming ordinary transparent synthetic resins into films or plates. At least one surface of the resin film or plate is coated with a coating composition containing a dye or pigment, an ultraviolet absorber, and a synthetic resin vehicle as described below, or one of the dye or pigment and the ultraviolet absorber of the present invention is coated. It can be produced by a method such as blending it into a film or board and coating at least one surface of the film or board with the other in the form of a coating composition as described above. Film-forming thermoplastic synthetic resins that can be used include, for example, polyvinyl chloride, polyvinylidene chloride, polyethylene, polypropylene, polystyrene, polyester, polyamide, polycarbonate, polymethyl methacrylate, polyacrylate, polyvinyl acetate, or polymers thereof. Contains mainly copolymers or blends, etc.
In particular, polyvinyl chloride, polymethyl methacrylate, polyethylene, and ethylene-vinyl acetate copolymer are suitable for reasons such as light resistance, light transmittance, and strength, and polyvinyl chloride is especially suitable. The ultraviolet absorber that can be incorporated into these synthetic resins can be appropriately selected from a wide range of types, taking into consideration the ultraviolet absorbing ability of the ultraviolet absorber and its compatibility with the synthetic resin used. Examples of usable ultraviolet absorbers include the following. Hydroquinone series - hydroquinone, hydroquinone disalicylate salicylic acid series - phenyl salicylate, paraoctylphenyl salicylate benzophenone series - 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-
Octoxybenzophenone, 2-hydroxy-
4-methoxy-2'-carboxybenzophenone, 2,4-dihydroxybenzophenone,
2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-benzoyloxybenzophenone, 2,2'-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy -5-sulfonebenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-hydroxy-4,4'-dimethoxy-5-sodium sulfobenzophenone, 4-dodecyloxy -2-hydroxybenzophenone, 2-hydroxy-5-chlorobenzophenone benzotriazole-based -2-(2'-hydroxy-
5′-methylphenyl)benzotriazole, 2
-(2'-hydroxy-5'-methylphenyl)-5
-carboxylic acid butyl ester benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)-5,6-dichlorobenzotriazole,
2-Hydroxy-5'-methylphenyl)-5-
Ethylsulfonebenzotriazole, 2-
(2'-hydroxy-5'-tert-butylphenyl)-
5-chlorobenzotriazole, 2-(2'-hydroxy-5'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-5'-aminophenyl)benzotriazole, 2-(2'-
Hydroxy-3',5'-dimethylphenyl)benzotriazole, 2-(2'-hydroxy-3',
5'-dimethylphenyl)-5-methoxybenzotriazole, 2-(2'-methyl-4'-hydroxyphenyl)benzotriazole, 2-
(2'-stearyloxy-3',5'-dimethylphenyl)-5-methylbenzotriazole, 2-
(2'-hydroxy-5'-carboxyphenyl)
Benzotriazole ethyl ester, 2-
(2'-hydroxy-3'-methyl-5'-tert-butylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)
-5-chlorobenzotriazole, 2-
(2'-hydroxy-5'-methoxyphenyl)benzotriazole, 2-(2'-hydroxy-
5'-Phenylphenyl)-5-chlorobenzotriazole, 2-(2'-Hydroxy-5'-cyclohexylphenyl)benzotriazole, 2
-(2'-hydroxy-4',5'-dimethylphenyl)-5-phenoxycarbonylbenzotriazole, 2-(2'-hydroxy-3',5'-dichlorophenyl)benzotriazole, 2-(2 ′−
Hydroxy-4',5'-dichloro)benzotriazole, 2-(2'-hydroxy-3',5'-dimethylphenyl)-5-ethylsulfonebenzotriazole, 2-(2'-hydroxy-5'- Phenylphenyl)benzotriazole, 2-(2'-
Hydroxy-4'-octoxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-methoxyphenyl)-5-methylbenzotriazole, 2-(2'-hydroxy-5'-methylphenyl)-5 -Ethoxycarbonylbenzotriazole, 2-(2'-acetoxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-
5-chlorobenzotriazole. Among these ultraviolet absorbers, benzophenone-based and benzotriazole-based ones are preferred, and among the benzophenone-based ones, 2,3-dihydroxy-4,4-dimethoxybenzophenone,
2,2'-dihydroxy-4-methoxybenzophenone and 2,2',4',4'-tetrahydroxybenzophenone;
(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)-5,6-dichlorobenzotriazole, 2-(2'-hydroxy-5'-tertiary butylphenyl)benzotriazole, 2-(2'-hydroxy-3'-methyl-5'-tert-butylphenyl)
Benzotriazole, 2-(2'-hydroxy-3',
5'-di-tert-butylphenyl)-5-chloro-benzotriazole and 2-(2'-hydroxy-
5'-Phenylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'- Octoxyphenyl)benzotriazole and the like are effective. Particularly suitable UV absorbers have the formula

[Formula] or

[Formula] In the formula, R ₁ and R ₂ are the same or different and each represents a lower alkyl group or an aryl group, particularly a phenyl group, and in particular R ₁ is preferably a branched lower alkyl group having C ₃ or less or It is a benzotriazole derivative represented by: a phenyl group, R ₃ represents a C ₆ or higher alkyl group, especially a C ₈ to _{C 10} alkyl group, and X is a hydrogen atom or a halogen atom, especially a chlorine atom. The amount of the ultraviolet absorber as described above can be varied widely depending on the type of ultraviolet absorber, the type of synthetic resin used, the thickness of the film or plate, etc. below,
In particular, in order to substantially completely block the transmission of ultraviolet rays of 380 nm or less, the following formula should be established between the amount of ultraviolet absorber and the thickness of the resulting film or plate: 15≦AB≦600, preferably 20≦AB ≦400 In the formula, A represents the blending amount (PHR) of the ultraviolet absorber, and B represents the thickness (μ) of the film or plate. It is particularly preferable that the following relationship is satisfied. Here, PHR means parts by weight per 100 parts by weight of synthetic resin. In addition, the amount (A) of the UV absorber varies depending on the type of synthetic resin and UV absorber, but in general
0.003~5PHR, especially for film 0.1~5.0PHR
It is preferable to fall within the range of . On the other hand, the dye or pigment that can be incorporated into the film-forming synthetic resin has a maximum absorption wavelength (λmax) of 590 to 625 nm, preferably 590 to 620 nm.
A blue dye or pigment that is within the range of m and has good compatibility with the synthetic resin can be used. Generally, pigments have better weather resistance than dyes and are therefore more suitable. Examples of pigments that can be used include the following. Metal-free phthalocyanine blue (C.
I.Pigment Blue16; CI74100), Phthalocyanine Blue (CIPigment Blue15; CI74160), Phthalocyanine Green (CIPigment Green7; C.
I.74260), Ultramarine Blue (CI77007), Deep Blue (CI77510 and 77520), Cobalt Blue (CI77346), Cerulean Blue (CI77368), Alkaline Blue Lake (CI42750A and 42770A), Peacock Blue Lake (CI42090 and 42025), Victoria Blue Rake (CI44045), Fast Sky Blue (C.
I.74180), Indanthrene Blue RS (CI69800),
Industhrene Blue BC (CI69825), Indigo (CI73000), etc. In addition, dyes that can be used include, for example, CI
Solvent Blue33, 35, 65, 79, 90, 95, and 122
etc. can be mentioned. These pigments or dyes can be used alone, or in combination of two or more. Particularly preferred among these colorants are phthalocyanine pigments, with metal-free phthalocyanine blue, phthalocyanine blue, and phthalocyanine green being particularly preferred. Among dyes, C.
I.Solvent Blue 33, 90, and 95 are preferred. The amount of the colorant mentioned above can be varied widely depending on the type of colorant used, the type of synthetic resin, the thickness of the film or board, etc., and the amount of colorant required in each case can be varied widely. A person skilled in the art can determine the blending amount.
It can be easily determined by conducting a simple short-term simulation experiment according to the Lambert-Beer law. However, in order to obtain a blue-colored synthetic resin film or plate having the light transmission properties shown in (b), (c), (d), and (e) above, it is generally necessary to mix a coloring agent. The relationship between the amount and the thickness of the film or board obtained is expressed by the following formula: 0.01≦PB≦20, preferably 0.1≦PB≦10 In the formula, P represents the blending amount (PHR) of the colorant, and B represents the thickness of the film or board. In many cases, the relationship shown by the thickness (μ) holds true. The amount (P) of the colorant varies depending on the type of synthetic resin and colorant, but is generally 0.0001 to 0.4PHR,
Preferably, it can be within the range of 0.001 to 0.1 PHR. In addition, in the case of phthalocyanine pigments that are particularly suitably used as colorants, the blending amount (P) may be very small, generally 0.001 to 0.06 PHR, preferably 0.005 to 0.04 PHR, and more preferably 0.01 to 0.06 PHR.
It can be in the range of 0.03PHR. In addition to the ultraviolet absorber, the synthetic resin film or plate used in the present invention may contain other conventional resin additives, such as plasticizers, lubricants, antioxidants, light stabilizers, antistatic agents, Moisturizer, heat stabilizer,
A small amount of dye, pigment, etc. can also be included. The above-mentioned film or plate can be manufactured using various methods known per se, such as a calender method, a T-die method, a melt extrusion method such as an inflation method, a press method, a solution casting method, and the like. The film or plate thus formed is
The thickness can vary over a wide range depending on the application, but generally a range of 15 to 5000 microns, particularly 20 to 500 microns, is suitable for the purposes of the present invention. The film or plate may include, if necessary,
It can also be used by laminating it on other synthetic resin films, sheets, glass, etc. for reinforcement purposes. Furthermore, on one or both sides of the coating material made of the film or plate of the present invention, methacrylic acid esters such as methyl methacrylate and ethyl methacrylate and/or methyl acrylate, ethyl acrylate,
Acrylic esters such as butyl acrylate and/or
Alternatively, a surface treatment agent made of a polymer or copolymer of α,β-unsaturated carboxylic acid such as methacrylic acid can also be applied. The agricultural covering material provided by the present invention is suitable for agricultural crops, especially fruit and vegetable plants, such as cucumber, watermelon, melon, house melon, open field melon, white melon, tomato, eggplant, green pepper, strawberry, okra,
Green beans, fava beans, edamame, sweet corn, etc. [Refer to “Vegetable Production Problems and Solutions” (Part 2) – Technology by Type – [Seibundo Shinkosha Co., Ltd., 1st edition published on August 25, 1970]] It can be advantageously used as a covering material for greenhouses, pipe houses, tunnels, etc. in the facility cultivation of crops.
(quality improvement effect, enriched cultivation effect, etc.) can be achieved. When cultivating agricultural products using the covering material of the present invention, it can be carried out in exactly the same manner as a normal facility cultivation method, except that the covering material of the present invention is used in place of the conventional covering material. No special consideration is required. That is, in a plant cultivation facility coated with the coating material of the present invention, such as a greenhouse, a pipe house, or a tunnel, crops can be cultivated in a greenhouse, in a greenhouse, or in a tunnel according to normal agricultural procedures. In this case, in order to adjust the temperature and humidity inside the greenhouse, greenhouse, or tunnel, it has been common practice to open skylights, perform shoulder ventilation, or perform hem ventilation. Exactly the same procedure can be carried out when using the coating material of the invention. Hereinafter, the production of the coating material of the present invention and the effects of cultivation using the same will be further explained with reference to Examples. Example A (Preparation of film) 100 parts by weight of polyvinyl chloride, 47 parts by weight of dioctyl phthalate (plasticizer), 1.5 parts by weight of dibutyltin maleate (thermal stabilizer), 0.5 parts by weight of zinc stearate (thermal stabilizer), Stear Calcium phosphate (heat stabilizer) 1.0 parts by weight, stearic acid (lubricant) 0.1 parts by weight, sorbitan monolaurate (antifogging agent) 1.0 parts by weight
Parts by weight and predetermined amounts of pigments and ultraviolet absorbers shown in Table 1 below were mixed, and the mixture was melt-extruded at 200°C with an extruder to a thickness of 0.1 m/cm.
Films Nos. 1 to 10 of m were obtained. The light transmittance curves of each film are shown in the attached FIG. 1. Further, Table 2 below shows the analysis results of the light transmission curve. Comparative Example A (Preparation of film) 100 parts by weight of polyvinyl chloride, 45 parts by weight of dioctyl phthalate (plasticizer), 1.5 parts by weight of dibutyltin maleate (thermal stabilizer), 1.0 parts by weight of zinc stearate (thermal stabilizer), stearin 0.1 part by weight of acid (lubricant), 1.0 part by weight of sorbitan monolaurate (non-drop agent), 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole (ultraviolet light) Absorbent) 1.5 parts by weight and blue pigment, P.
0.08 parts by weight of V.First Blue A-2R was mixed and the mixture was melt-extruded at 200°C using an extruder to obtain film No. 11 with a thickness of 0.1 m/m. The light transmittance curve of this film is shown in FIG. Further, Table 2 below shows the analysis results of the light transmission curve.

【table】

【table】

[Table] Examples 1 to 2 and Comparative Examples 1 to 7 Green beans (variety: Shin-Edogawa) were sown on June 16th, and seedlings were planted on June 24th with a row spacing of 60 cm and a plant spacing of 30 cm. Tunnel cultivation was carried out while covered with each film shown in Table 1. Harvest is July 27th
The results are shown in Tables 3 and 4. Cultivation of the green beans, that is, fertilization, watering, and temperature control, were carried out according to conventional methods throughout the entire cultivation period.

【table】

【table】

【table】

[Table] From the results in Table 3, in the film No. 1 and No. 2 covered plots, the number of nodes and lateral branches was surprisingly large despite the fact that the amount of plant height elongation was smaller than in the other film covered plots. It turns out that there are many things. This result is a film
In covered plots No. 1 and No. 2, the plant height of green beans was appropriately suppressed, and the internode length was short, indicating that the plants grew into tall, full-bodied plants. In addition, as is clear from Table 4, film
In No. 1 and No. 2 covered plots, compared to other film-covered plots, the difference in yield by season is extremely small, the phenomenon of "tiredness" of plants is hardly observed, and the total yield is also overwhelming. There are many, the average weight of the pods is large, and the quality is also excellent. Examples 3 to 4 and Comparative Examples 8 to 16 Various films shown in Table 1 were spread in 10 pipe houses (opening 4.5 m, depth 15 m). The cucumbers (variety: Tokiwa Hikari No. 3 P type) sown on November 20th were planted in each pipe house on December 27th.
They were planted at a rate of 4.5 plants per tsubo, and harvesting began on February 6th and cultivation continued until early May. Cultivation of the cucumber, that is, fertilization, watering, and temperature control, was carried out according to conventional methods throughout the entire period. The results are shown in Table-5.

[Table] From the results in Table 5, in the plots covered with Film No. 1 and No. 2, the elongation of plant height was moderately suppressed, the difference in yield between seasons was clearly small, there was no fatigue phenomenon, and there was no fatigue phenomenon throughout the entire cultivation period. It can be seen that high yields and stable harvests can be achieved. Example 5 and Comparative Examples 17 to 23 A tomato cultivation experiment was conducted using the pipe house and covering material used in Example 3 as they were. 8
Sow tomatoes (variety: large size Zuikou) on the 15th of the month,
On January 4th, we planted 9 plants per tsubo in a pipe house, and harvesting began on January 3rd. Cultivation of the tomatoes, ie, fertilization, watering, and temperature control, were carried out in accordance with conventional methods.

[Table] As is clear from the results in Table 6, the film
In No. 1 cover plot, compared to other cover plots, the plant height is properly controlled, the seasonal yield is always high and stable yields are achieved, and the incidence of concentric and radial fissures in the harvested tomatoes is extremely low. I understand that. Example 6 and Comparative Example 24 Green peppers (variety: Shinsakikake) were sown on August 10th, and film No.-1 shown in Table-1 was sown on October 7th.
(Example 6) and film No. 3 (Comparative Example 22) were used for greenhouse cultivation. Cultivation of peppers was carried out according to conventional methods throughout the period, including fertilization, watering, and temperature control. Harvesting was carried out from October 20th to the end of May, and the fatigue phenomenon was not observed in the plots covered with film No. 1 compared to the plots covered with film No. 3, and the difference in yield between seasons was extremely small, and the total yield was also low. We were able to see an increase in quality, and we were able to generate high profits.

[Brief explanation of the drawing]

Figure 1 shows the films used in Examples and Comparative Examples.
FIG. 2 is a diagram of wavelength-specific light transmission curves for films No. 1 to No. 11.

Claims (1)

[Scope of Claims] 1. Having the following light transmission properties, namely (a) substantially blocking the transmission of light having a wavelength of at least 370 nm or less, and (b) having an absorption maximum in the wavelength range from 440 nm to 700 nm. is between 595 and 620 nm, and the light transmittance at the absorption maximum is within the range of 75 to 85%, and (c) the average transmittance of light with a wavelength between 440 and 590 nm is at least 85% or more. , (d) The average transmittance of light with a wavelength between 600 and 700 nm is 77
~88%, and (e) the average transmittance of light for wavelengths between 400 and 500 nm vs.
The average transmittance ratio of light with a wavelength between 600 and 700 nm is less than 1.2 (f) Transmits 15% or more of light with a wavelength of 400 nm, and
The average transmittance of light with wavelengths between ~440nm is 65~90
% An agricultural covering material suitable for cultivating fruit and vegetable plants characterized by being made of a blue-colored transparent synthetic resin film or board.