JP3687455B2 - Crop cultivation method and crop quality improving agent - Google Patents

Description

【Technical field】
[0001]
The present invention relates to an improved method for cultivating crops, particularly vegetables. The present invention provides a cultivation method capable of harvesting crops with reduced contents of nitric acid and oxalic acid, and further increased contents of vitamins and minerals, increased sugar content, and improved quality. . The present invention also relates to an agent for improving the quality of crops used for carrying out this cultivation method.
[Background]
[0002]
In the cultivation of hydroponic crops, in addition to nutrients such as nitrogen, phosphate, potassium, calcium, magnesium, and sulfur, trace elements such as manganese, iron, zinc, molybdenum, boron, and copper are added to nitrate, hydrochloric acid, etc. It is dissolved in water in the form of salt, sulfate or ammonium salt and given to crops. A standard nutrient solution formulation is known as a “horticultural laboratory prescription” (commonly known as “horticultural prescription”), and various modifications are used as necessary.
[0003]
On the other hand, the nutrient supply method in soil cultivation, apart from the so-called organic fertilizer, uses the above-mentioned mineral resources containing the essential ingredients as raw materials, processed them, or obtained by synthesis, urea, nitrate, Fertilizers in the form of hydrochlorides, sulfates, ammonium salts, carbonates, silicates, etc., are used by applying fertilizer according to the type of crop or soil. If the pH of the soil is not in the preferred range, soil improvers and the like to bring it to the desired level are also used with fertilizers.
[0004]
Plants generally tend to retain a significant proportion of the incorporated nitrogen in the body in the form of nitric acid. However, nitric acid is likely to combine with other components such as certain amines inside the ingested human body to make a substance suspected of causing carcinogenicity. Therefore, it is desirable that the nitrate content in the harvested crop is low.
[0005]
Leaf vegetables such as spinach accumulate a large amount of oxalic acid in the body. Oxalic acid is a substance that causes stones, and you should avoid taking too much. Fortunately, about half of oxalic acid melts when the plant is boiled, and the amount remaining in the food decreases, so the traditional food form, such as sea urchin, can avoid oxalic acid damage considerably. However, given the increasing tendency to eat vegetables in recent years, we want to reduce the oxalic acid content in vegetables as much as possible.
[0006]
As a cultivation method for obtaining a crop of low nitric acid and low oxalic acid, when hydroponics is used, a nutrient interruption method for restricting nutrients to be supplied and an osmotic pressure regulator for suppressing water absorption are used. Apart from these, early harvesting, in which harvesting occurs before the concentration of the component in question increases, is also being considered. In order to achieve the purpose of low nitric acid and low oxalic acid in soil cultivation, it is necessary to limit the amount of fertilizer used in the form of nitrate, or to use chemical fertilizers in which nitrogen in the form of nitrate acts slowly. Use with fertilizers as a countermeasure. Of course, early harvesting is also possible.
[0007]
An example of the means known so far is to cultivate the inside of a vegetable by growing it with a hydroponic fertilizer solution that contains little or no nitrate nitrogen for a certain period of time before harvesting. A hydroponic method is disclosed in which nitrate nitrogen remaining in the plant is consumed and grown (Patent Document 1). However, most vegetables are nitrite plants, and the cultivation method that does not give nitrate nitrogen too early will slow down the growth and limit the growth, resulting in a low yield.
[0008]
Similarly, there is a hydroponics method in which the nitrogen source is used in an ammonia state instead of a nitrate state. Vegetables are nitrophilic plants, but if ammonia nitrogen is present, it can also be partially absorbed. Accordingly, attempts have been made to increase the proportion of ammonia nitrogen as a nitrogen source in the nutrient solution to actively absorb ammonia nitrogen and reduce the nitrate content of plants. However, this method tends to cause poor growth and does not lead to a significant quality improvement.
[0009]
In the case of the soil cultivation method, it is difficult to adopt the method described above for the hydroponics method. Even if the nitrogen source is in the form of urea or ammonia, it undergoes nitrification by microorganisms in the soil, and when nitrogen in the air is oxidized, it becomes nitric acid, dissolves in rainwater and falls to the ground. Therefore, it is virtually impossible to grow crops under conditions where nitric acid is removed from the soil.
[Patent Document 1]
Japanese Patent Publication No. 7-102051 [Disclosure of the Invention]
[Problems to be solved by the invention]
[0010]
The object of the present invention is to improve the quality of crops, especially vegetables, by reducing the content of nitric acid and oxalic acid contained in the crops at the time of harvest, whether by hydroponics or soil cultivation. An object of the present invention is to provide a method for cultivating a crop from which a crop can be obtained. It is also within the scope of the present invention to provide crop quality improvers for use in carrying out the method.
[Means for Solving the Problems]
[0011]
The method for cultivating a crop of the present invention that achieves the above object is a method for cultivating a crop capable of harvesting a crop with improved quality, wherein potassium acetate , acetic acid are used from the beginning of the cultivation period or at least at the end of the cultivation period. A crop cultivation method characterized by harvesting a crop having reduced nitrate and oxalate contents by applying an appropriate amount of one or more acetates selected from ammonium and calcium acetate .
[0012]
The crop quality improver used in this cultivation method is a fertilizer and / or soil improver containing at least one active ingredient, and one or more selected from potassium acetate, ammonium acetate and calcium acetate. It is a quality improving agent that contains an acetate and is applied to the cultivation of the crop to give a crop with a reduced content of nitric acid and oxalic acid.
【The invention's effect】
[0011]
When a crop is cultivated according to the method of the present invention, the content of undesired substances in the crop, such as nitric acid that forms a carcinogen, oxalic acid that causes stones, is greatly reduced, and quality is improved. Crops can be harvested. At the same time, it is possible to increase the content of vitamin C and minerals, which are preferable components in the crop. Combined with the reduction of bad ingredients and the increase of active ingredients, it helps prevent modern people's diseases and provide nutrition.
[0012]
An increase in the amount of dry matter in harvested crops means that vegetables with high fiber content can be produced. As is well known, fiber intake stimulates metabolism and helps digestive activity.
[0015]
From the fact that the value of sugar content in crops is increasing, it can be seen that better vegetables can be provided also in terms of taste.
[0016]
The crop quality improving agent of the present invention can be easily applied to both hydroponics and soil plowing, and can provide an effect easily.
BEST MODE FOR CARRYING OUT THE INVENTION
[0017]
As described above, one or more kinds of acetates selected from potassium acetate, ammonium acetate, and calcium acetate are used. Other acetates can be added to this.
[0018]
The crop quality improving agent according to the present invention can be in a liquid form, typically a nutrient solution used for hydroponics, or a liquid manure used for soil cultivation. Moreover, the form of the powder or granule used for a soil cultivation method is also possible.
[0019]
The cultivation method of the crop of the present invention can be applied to both hydroponics and soil cultivation methods, but from the viewpoint of easily controlling the nutrients given to the crop and reliably obtaining the effects of the invention, More suitable. In the case of hydroponics, cultivation is carried out using a nutrient solution of a normal prescription until the beginning and midway of the cultivation period, and a nutrient solution containing acetate as an active ingredient is used from the middle. This switching takes place between 1 and 10 days prior to harvesting, preferably between 2 and 3 days.
[0020]
The amount of acetate to be contained in the nutrient solution is preferably in the range of 0.1 to 4 mM / L in terms of acetate ion concentration. At low concentrations where the acetate ion concentration is less than 0.1 mM / L, the significance of using acetate is poor and the effects of the invention cannot be obtained. On the other hand, if the amount of acetate ions is too large, crop growth may be suppressed. High concentrations above 4 mM / L are often detrimental. The suitable acetate ion concentration varies slightly depending on the type of crop, but is usually in the range of 1 to 3 mM / L.
[0021]
When cultivating crops by the soil cultivation method, it may be applied from the beginning of the cultivation period, but when the present invention is carried out using a fertilizer or a soil conditioner added with acetate, There is no need to increase the number of steps, which is advantageous. Of course, if the amount of spraying does not matter, it may be given separately. When applied from the beginning, that is, for example, when acetate is given to both the manure and top fertilizer, acetic acid is used, and the manure is 5 to 75 kg / 10 ares at a time, and a total of several times is 10 to 150 kg / 10 ares Appropriate topdressing is 5-50 kg / 10 ares per time, and a total of several times is 10-100 kg / 10 ares.
[0022]
The cultivation method of the present invention can be applied particularly to leafy vegetables to harvest crops with a reduced nitric acid content, but is particularly significant when targeting oxalic acid high contents such as spinach. It is known that crops with high nitric acid content tend to have high oxalic acid content.
【Example】
[Example 1] Hydroponic cultivation of spinach [0023]
Nutrient solutions A and B were prepared with the two prescriptions shown in Table 1. The nutrient solution A is a modified version of the garden trial formulation, and the nutrient solution B is obtained by further replacing a part of the nutrient solution B with acetate according to the present invention.
[0024]
Table 1
Ingredient nutrient solution A nutrient solution B
Potassium nitrate 5.5 mM / L 5.5 mM / L
Potassium sulfate 1.25 0.75
Potassium acetate-1.0
Calcium nitrate 2.75 2.75
Calcium chloride 1.25 0.75
Calcium acetate-0.5
Ammonium dihydrogen phosphate 4/3 4/3
Magnesium sulfate 1.25 0.75
Magnesium acetate-0.5
Trace element: Mn 0.5ppm 0.5ppm
Zn 0.05 0.05
Cu 0.02 0.02
Fe 3 3
Mo 0.01 0.01
B 0.5 0.5
Three sections were prepared, and spinach was cultivated using the above nutrient solution under the following supply conditions. The nutrient solution was changed every 2-3 days, and the pH was adjusted every day.
[0025]
Section I Use nutrient solution A consistently from sowing to harvest Section II Use nutrient solution A at the beginning and switch to nutrient solution B two days before harvest Section III Use nutrient solution A at the beginning and harvest 2 Change to deionized water from which nutrients were removed from the previous day Cultivation period 35 days Number of strains 20 pH 6.0 each 70L
After the cultivation period of 35 days, the above-ground part of the harvested spinach was analyzed, the contained components were quantified, and the results shown in Table 2 were obtained.
[0026]
Table 2
Compartment Vitamin C Ca Mg K nitric acid oxalic acid Ground weight, dry matter, sugar content <br/> Zone I 1,166 531 736 7,601 3,885 9,095 25.5 8.88 5.1
District II 1,941 988 858 8,977 804 5,864 26.5 9.97 5.8
Chapter III District 1,251 671 746 7,110 2,914 8,364 23.7 9.03 5.3
n = 12
Unit Ground weight is g / stock Dry matter is% Sugar content is Brix Others are ppm / fresh weight [Example 2] Spinach cultivation in spinach [0027]
A mixture of (original fertilizer + soil conditioner) was prepared with two types of prescriptions with application rates (unit: kg / 10 are) as shown in Table 3. Mixture C is conventional and D uses acetate instead of soil amendment according to the present invention.
[0028]
Table 3
Component Mixture C Mixture D
Normal chemical fertilizer Nitrogen 15 15
Phosphoric acid 18 18
Potassium 15 15
Soil improver Calcium carbonate 50
Calcium acetate 79 ^*
* 79 kg of calcium acetate has the same number of moles as 50 kg of calcium carbonate.
[0029]
Using a 30L planter with general black soil, set up 2 sections and apply the mixture of the above 2 types as follows:
Section IV Mixture C
Zone V Mixture D
Spinach was cultivated. 20 shares each. Harvested after 42 days of cultivation, analyzed in the same manner as in Example 1, and the results shown in Table 4 were obtained.
[0030]
Table 4
Compartment Vitamin C Ca Mg K Nitric acid Succinic acid Ground weight Dry matter Sugar content <br/> Division IV 973 613 746 7,601 4,284 9,713 23.7 9.03 4.0
Section V 1,942 992 858 8,792 817 5,422 24.8 9.44 4.5
n = 20 Unit: Same as above

Claims (5)

A method for cultivating a crop capable of harvesting a crop of improved quality , comprising one or more acetic acid selected from potassium acetate, ammonium acetate and calcium acetate from the beginning or at least at the end of the cultivation period A method for cultivating a crop, characterized by harvesting a crop having a reduced content of nitric acid and oxalic acid by applying an appropriate amount of salt. Cultivation is based on hydroponics, and contains one or more acetates selected from potassium acetate, ammonium acetate and calcium acetate from the middle of the cultivation period , and the acetate ion concentration is 0.1. The cultivation method of the crop of Claim 1 implemented using the nutrient solution which is -4 mM / L. Cultivation is based on soil cultivation, and one or more acetates selected from potassium acetate, ammonium acetate and calcium acetate for fertilizer or soil conditioner applied as additional fertilizer during the cultivation period The method for cultivating a crop according to claim 1, wherein the cultivation is carried out using an amount added to the acetic acid content so that a single application rate is 5 to 75 kg / 10 are. The method for cultivating a crop according to any one of claims 1 to 3, wherein the cultivated crop is spinach. A quality improving agent for additional fertilizer used in the method for cultivating a crop according to claim 1 to 4, wherein the fertilizer and / or soil improver containing at least one active ingredient is used as potassium acetate as an acetate. , one or quality improving agents of crops by blending two or more kinds selected from ammonium acetate and calcium acetate.