JPS60164413A - Culture of citrus fruits - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for cultivating citrus.

More specifically, the present invention relates to a cultivation method that allows high-quality citrus fruits to be harvested at a high rate.

Traditionally, citrus fruits have been widely cultivated in Japan with warm climates such as Shikoku and Nanki. Citrus fruits, like other agricultural crops, are susceptible to the effects of the weather, and their production varies depending on the weather. In other words, in years of poor harvest, market prices rise, and in years of good harvest, production adjustments such as flower and fruit thinning are carried out in order to cope with the market crash.
The market was not considered stable by both producers and consumers.

Chikara/Kira cultivation is usually carried out in vast mountainous areas.
Because the cultivation area is large and the trees are large, artificial cultivation of leafy vegetables, root vegetables, and fruit vegetables in greenhouses (...) has not been practiced much in the past.

However, cultivating citrus under artificial conditions, such as in greenhouses, can eliminate natural or climatic influences, promote growth, and hasten its harvest time, thus allowing it to be shipped early and at a high price. In addition, it is possible to prevent the harvest period from concentrating on a short period of time as is the case with open field cultivation, and it has the effect of decentralizing the labor force. For producers, it is possible to disperse the labor force.

Being able to ship fruit at a high price is extremely advantageous. For this reason, recently, research has been conducted on techniques for cultivating citrus fruits in greenhouses, and these techniques have been put into practical use.

The cultivation method that has been put into practical use is to cover the fruit trees with a covering material from winter to early summer and seal them to create a greenhouse, and to maintain the temperature inside the greenhouse at a constant level during the coldest months. It was a focused method.

With the aim of providing a cultivation method for harvesting high-quality citrus fruits at a high rate, the inventors of the present invention have conducted intensive studies and found that when citrus fruit trees are grown by covering them with a covering material, the present inventors have discovered that the present inventors have developed a method for cultivating citrus fruit trees by covering them with a covering material. The inventors have discovered that the object can be achieved by using a material with specific optical properties, and have completed the present invention.

Therefore, the gist of the present invention is that when cultivating citrus fruits under a covering material, each of the measured values of outdoor solar radiation, direct solar radiation, and scattered solar radiation measured with an illuminance meter on a clear day, When the index is /θO, the indices of the solar radiation, direct solar radiation, and scattered solar radiation measured with an illumination meter under the covering material at the same time are zs or more and 7.9, respectively. −
A method for cultivating citrus fruits characterized by using a covering material exhibiting characteristics of 90.176 or higher.

The present invention will be explained in detail below.

In the present invention, citrus fruits include Satsuma mandarin, Kishu mandarin, summer mandarin, Hesaku, Iyokan 1 Hyuganatsu, Naruto, sweet orange, grapefruit, Buntan (Bunha),
Refers to those belonging to the Rutaceae family, such as lemon, kumquat, daidai, sweet daisy, ponkan, yuzu, and sudachi.

In the present invention, the amount of solar radiation in the open field refers to the amount of solar radiation measured with an illumination meter on a clear day in an orchard where citrus trees are cultivated without using covering materials, and includes direct solar radiation and scattered solar radiation. It means the sum with quantity. Direct solar radiation in an open field is the amount of solar radiation coming directly from the sun, excluding scattered light from the sky, measured on a plane perpendicular to the direction of incidence of the sun's rays on a clear day. However, the amount of scattered solar radiation in open ground is
It is the value obtained by subtracting the direct solar radiation of the open field from the solar radiation of the open field, and means the amount of scattered light from the sky.

In the present invention, the amount of solar radiation under the covering material, the amount of direct solar radiation, and the amount of scattered solar radiation are measured by a luminance meter placed approximately 7 meters above the ground inside a greenhouse in which citrus trees are covered with the covering material. Refers to the measured value. The amount of solar radiation under the covering is the amount of solar radiation on a clear day that passes through the covering and reaches the illumination meter (the sum of the direct solar radiation and the scattered solar radiation)
Direct solar radiation under the coating means the amount of solar radiation on a clear day when the amount of radiation transmitted through the coating material and coming from the direction of the sun is measured perpendicular to the direction of incidence of the solar rays, The amount of scattered solar radiation under the covering means the value obtained by subtracting the amount of direct solar radiation under the covering from the amount of solar radiation under the covering.

c) The amount of solar radiation in the open field and under the covering by covering materials, the amount of direct solar radiation, and the amount of scattered solar radiation are each measured using a luminometer on a clear day, at the same time, and in the same area. Examples of illuminometers that can be used include photocell illuminometers, phototube illuminometers, Gorchinski illuminometers, agricultural test sample pyranometers, and front-type pyranometers. Measurements in open ground and under cover should be made using the same type of luminometer.

When using the method of the present invention, when each of the measured values of outdoor solar radiation, direct solar radiation, and scattered solar radiation measured with an illuminance meter on a clear day is set to 100, the illuminance under the covering material at the same time is The index of each measurement value of solar radiation, direct solar radiation, and scattered solar radiation measured by a meter is 25 or more, and 2! A coating material exhibiting properties of 0, //, 5' or more is used.

Using a material with the above optical properties as a coating material will improve both the flowering rate and fruit set rate, as well as the quality of the fruit (in terms of malformation rate, pericarp thickness, fruit sugar content, etc.). , and can also improve fruit yield.

The range of optical properties of the coating material used in the method of the present invention is
Shown in Figure 1.

In Figure 1, the horizontal axis shows the index of the amount of direct solar radiation under the covering by the covering material, and the vertical axis shows the index of the amount of scattered solar radiation under the covering by the covering material, and it is preferable to use a covering material whose index falls within the shaded range. It means that.

Examples of the coating material include inorganic sheets, organic sheets, organic films, etc., and any material can be used without any particular restriction as long as it has the above-mentioned optical properties.

An example of an inorganic sheet is a glass plate.

In order to impart the above-mentioned optical properties, (a) roughening the surface (by etching or applying fine powder to the surface), (b) pasting a synthetic resin film with a roughened surface, A method such as pasting a synthetic resin film containing powder may be used.

The organic sheet or film may be a thermoplastic resin sheet or film. As a thermoplastic resin,
Examples include polyvinyl chloride, polyethylene, polypropylene, polystyrene, polyester, polyamide, polymethyl methacrylate, polyacrylate, polycarbonate, polyvinyl acetate, and ethylene-vinyl acetate copolymer. In order to impart the above-mentioned optical properties to a sheet or film made of these resins, (2) Roughening the surface of the sheet or film (a method of roughening the surface when forming a sheet or film, or adding fine powder to the surface) Coating method) A method of blending sium etc. into a sheet or film, (f) A method of forming a sheet or film with a smooth surface,
A method such as attaching a sheet or film prepared by the method described in (2) or (e) may be used.

When manufacturing a sheet or film from the above thermoplastic resin, the base resin material may contain plasticizers, lubricants, antioxidants, light stabilizers, antistatic agents, heat stabilizers, additives, etc., as necessary.
Antifogging agents, dyes, pigments, etc. can be added.

Sheets or films can be prepared from the base resin by various methods known per se, such as calendering, melt extrusion, compression molding.

It can be manufactured by a solution casting method or the like.

Cultivation of citrus fruits according to the present invention is carried out from around March to around the end of June while being covered with a coating material having the above-mentioned optical properties. In other words, among citrus fruits, during the germination and leaf formation period from around July to late June for half-phase, and from July to late June for late citrus, Make sure the temperature is not too low.

3. Avoid leaf burn during the evening moon when the sun's rays are strong.

To cover citrus trees, it is recommended to build a frame that is taller than the height of the tree, and to cover with strong materials such as metal, several to dozens of trees should be covered in one building rather than covering each tree individually. It is preferable to

Citrus leaves begin to curl when the temperature drops below -3℃ in winter, and if this temperature continues for a long period of time, they lose their vitality.When the temperature gets even colder, the leaves begin to scorch, fall off, and some even die. Therefore, in the winter, the greenhouse is sealed tightly and heated by oil heating or other heating means to keep the temperature inside the greenhouse within the range of 75 to 20 degrees Celsius at night and 2j to 30 degrees Celsius during the day. It is best to maintain From March to June, when the sun's rays are strong during the day, trees and leaves tend to peel off, so this is to adjust the temperature and humidity inside the greenhouse.

If necessary, open skylights, provide shoulder ventilation, and raise the hem.

According to the method of the present invention, tree pruning, pruning, soil management, fertilization, pest control, etc. while cultivating citrus under the covering material may be carried out in accordance with conventional greenhouse cultivation.

When using the method of the present invention, citrus trees are covered and used in winter, especially before flowering, to maintain and promote the growth of these citrus trees. This is to prevent

When cultivated under a covering with a covering material that satisfies the above-mentioned optical properties, it is possible to constantly maintain the room temperature during the winter at a desirable temperature, and the amount of sunlight is altered by the covering material during the sunny day. As a result, there is no leaf burn due to abnormal sunlight irradiation, photosynthesis is promoted by the modified sunlight, and high quality fruits (low incidence of malformations, thin pericarp, high sugar content, etc.) ) can be harvested in large quantities. Furthermore, it is possible to protect trees during abnormally cold waves and prevent frost damage, bird damage, and damage from wind and rain.

Therefore, the present invention greatly contributes to citrus cultivators.

Next, the present invention will be explained in detail based on examples.
The present invention is not limited to the following examples unless it exceeds the gist thereof.

EXAMPLE A framework of a vibe house was constructed that can accommodate 70 four-year-old, early-maturing fruit trees grown in a mandarin orange orchard in Matsuyama City, Ehime Prefecture. Showa! On July 6th/θ day, thickness O6/
Soft polyvinyl chloride film for the throat, solar radiation (index>90 range, direct solar radiation (index) L!''θ, scattered solar radiation (index) / 30 (shown as A in Figure 1) ) coated with

Showa! 6/7/The temperature inside the house is heated by oil heating from sunset, and the Showa period of budding! Until February 7, 2017, the temperature was maintained in the range of 75 to 20°C at night and in the range of 25 to 3θ°C during the day. From February 2nd of the same year, the temperature inside the house will be reduced all night.
Maintain the temperature within the range of J~/,r°C and daytime/dJj~30°C, and stop heating the house using the oil heating method after 2-2 of the same year.1. In mid-June of the same year,
The film on the side of the house was removed from the frame of the pipe house.

Showa! Harvesting began on February 2nd, 2017, and continued until February 70th of the same year. The resulting fruits were measured for malformation incidence, pericarp thickness, -equivalent yield, and fruit quality, and the results are shown in Table 1.

Comparative example In the examples described in the Examples, as a covering material.

It is a soft polyvinyl chloride film with a thickness of O0/l1lI+1, and the amount of solar radiation (index) is 9θ, and the amount of direct solar radiation (index)?
! , scattered solar radiation/θo (indicated as B in FIG. 7), all operations were performed in the same manner as described in the examples.

July 1972! Harvesting began on the 10th of the same year and continued until the 10th of the month. Malformation incidence for the obtained fruit,
The thickness of the pericarp, the yield of the fruit, the quality of the fruit, etc. were measured, and the results are shown in Table 1.

Chapter/Table G residence〕*l　Based on visual judgment.

"None" means a normal fruit with no malformations; “Mild” indicates that the fruit weight has collapsed, but the fruit is light. Fruits with commercial value in degrees, “medium” are Fruits with extremely malformed fruit weight and no commercial value. In fact, "severe" means that the fruit weight is seriously malformed. Meaningless fruit, all of them. Ru.

*2 “Sugar content”: Refractometer (manufactured by Atago Co., Ltd.)
The values shown are those measured using conventional methods.

*s "g//θ0-citric acid"...Fruit juice/θocc
It means the I number of citric acid in the cc, and it means the solid content/acid (weight ratio) contained in cc determined by titration with O0/normal caustic soda solution.

If this value is less than 7θ, the acid I feel the taste, and if it is 5-72.0 or higher, I feel the sweetness.

*5 Leaf Area Index refers to the ratio of the area of one leaf to the area of cultivated land (leaf area index).

From Table 1, the following is clear.

(1) When the method of the present invention is used, the incidence of malformed fruit is low, and the yield of Q fruit with sufficient commercial value is high.

(2) When using the method of the present invention, the pericarp generally tends to be thin. However, the reason why the stem part is thick is that the power coming in per piece is heavy, so it is assumed that it is 7... to support this.

(3) When the method of the present invention is used, compared to the comparative example, the yield is increased by j%, and the weight per fruit is also heavy.
Large fruits were harvested.

(4) The fruit obtained by the method of the present invention has a high sugar content and is excellent in sweetness.

(5) When using the method of the present invention, Leaf Area
It can be seen that the anaex (leaf area index) is small, and efficient assimilation is performed with a small number of leaves.

[Brief explanation of drawings]

In Figure 1, the horizontal axis shows the index of the amount of direct solar radiation under the covering by the covering material, and the vertical axis shows the index of the amount of scattered solar radiation under the covering by the covering material, and it is preferable to use a covering material whose index falls within the shaded range. Show that. Point A indicates the film used in the example, and point B indicates the film used in the comparative example. Applicant: Mitsubishi Monsanto Toy Vinyl Co., Ltd. (7 people) Agent: Patent attorney - (7 other people)

Claims (1)

[Claims] (1) When cultivating citrus under a covering material, the respective measured values of outdoor solar radiation, direct solar radiation, and scattered solar radiation measured with a luminometer during clear weather are expressed as index/θθ.゛The indices of the measured values of solar radiation, direct solar radiation, and scattered solar radiation measured by the illumination meter under the memory of the abduction at the same time are each! As described above, a method for cultivating citrus fruits is characterized in that a coating material exhibiting characteristics of 2 to 9 theta, //o or more is used.