JP2008061570A - Vegetable with low nitrate nitrogen, and method and system for cultivating the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide vegetables with low nitrate nitrogen having low content of nitrate nitrogen owing to hydroponics, and free from giving harmful effect to a human body. <P>SOLUTION: A supply and circulation system 1 of culture solution comprises supplying to a perforated hydroponic pipe whose each hole is planted with a plant, from a culture solution supply pipe 21 with a pump 13 through a control valve 111 from a culture solution storage tank 11, and collecting culture solution collected from a culture solution collecting pipe 23 in the culture solution storage tank. Plants are grown by supplying culture solution for a fixed period, collected through stopping supply of culture solution before a harvesting time and cultivated by supplying water from a sprinkling water storage tank. As a result of this, it is possible to consume nitrate nitrogen accumulated in a plant body and lower nitrate nitrogen concentration to ≤450 ppm so as to harvest. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a low nitrate nitrogen vegetable, and particularly to a low nitrate nitrogen vegetable having a nitrate nitrogen content of 450 ppm or less produced by hydroponics.

The fact that vegetables containing nitrate nitrogen (NO ₃ --N) are harmful to human health is a problem that has plagued agricultural specialists for a long time, but it is also an effective solution for agricultural producers. This is a technical challenge. Until now, there has been almost no work on the control of the content of nitrate nitrogen (NO ₃ --N), and there is no need to discuss technical progress. Until the application of the present invention, in addition to trying to change the genes and components of crops such as vegetables using genetic recombination technology, experiments and considerations that add quantitative control to harmful substances contained in vegetables are There was almost no. What are the agricultural products produced using genetic recombination technology, which have a negative impact on the human body, what is the impact of genetic recombination technology on agriculture and ecosystems, and what are the unforeseen risks that will occur? It is a difficult problem that cannot be known without long-term observation. So far, there are no published papers, data or research that convince people in academic societies and industries.

  Cultivation and production of the “low nitrate nitrogen vegetables” of the present invention does not reduce the detected amount of nitrate nitrogen to 450 ppm or less by genetic recombination technology or other related technologies, but “hydroponic cultivation apparatus” and “culture medium” This is due to the result of the “Suspended Cultivation Method” causing sufficient vegetable photosynthesis. It uses the laws of nature to produce low nitrate nitrogen vegetables. The present invention adds quantitative control to harmful substances that adversely affect the human body contained in vegetables, and so far, no technology, news reports or papers that are relevant or similar to the present invention have been found. There wasn't.

Although human social forms such as hunting society, grazing society and agricultural society have progressed, in the last two hundred years the agricultural revolution caused by the industrial revolution and industrial revolution (green revolution) has greatly improved the production efficiency of crops did. Increased crop yields have saved many people from hunger. At present, the evaluation of the agricultural revolution is generally considered to have advantages over disadvantages, but the agricultural revolution is prematurely caused by excessive land development and use, leading to a large amount of soil degradation. While using fertilizer and trying to improve the harvest, the efficiency deteriorated. Such a vicious cycle spurs the oxidation of the cultivated land, and the original power of the land is completely lost. Conventional farming consumes a large amount of water for irrigation, but as water resources become increasingly valuable, hydroponic cultivation with higher harvesting efficiency has emerged and is now regarded as one of the important farming methods. ing. The Earth's temperature has risen by 0.6 ° C over the last century of the 20th century, and a computer simulation on the impact of global warming estimated that it will rise 3.3 ° C at the end of this century. Ice melts, raises the sea level, reduces or disappears along the coastal agricultural land. Except for the Amazon River and Congo River, which are the seven major rivers in the world, the amount of water has declined, and in the Yellow River in China, the phenomenon that the river partially withered in the last 50 years has occurred 17 times. As a result of global warming, extreme weather events such as severe storms frequently occur, the weather undergoes significant changes in a short period, disturbs the natural laws of precipitation that rainwater wets the land, conventional farm management and agricultural products This is considered to have a serious impact on the yield and price of the rice. Therefore, hydroponic cultivation with high production efficiency has become one of the options for producers to increase production efficiency. Hydroponics has improved problems such as cultivated land reduction, large consumption of irrigation water, and land degradation due to chemical fertilizer abuse. High residual amount of nitrogen produced adverse effects such as harming people's health. The present invention provides a creative and effective improvement method for the above-mentioned conventional farming, hydroponics or organic cultivation that cannot provide environmental destruction, wasted irrigation water, and safe and sanitary vegetables. provide.
Japanese Patent No. 3687455

  An object of the present invention is to provide a low nitrate nitrogen vegetable that has a low nitrate nitrogen content by hydroponics and does not adversely affect the human body.

In order to achieve the above object, the present invention provides a low nitrate nitrogen vegetable and a cultivation system and method thereof. The low nitrate nitrogen vegetable of the present invention is characterized in that the detected amount of nitrate nitrogen is 450 ppm or less. The method for reducing the nitrate nitrogen content of a vegetable according to one embodiment of the present invention uses “hydroponic cultivation apparatus” and “culture liquid supply interruption cultivation method” as examples in the description of this embodiment. This method has the ability to reduce the nitrate nitrogen content of vegetables to 450 ppm or less (see [Fig. 1]), saves irrigation water, simplifies the collection and reuse of culture fluids, and drains hydroponic wastewater. In terms of its features and effects, such as eradication, increase in the growth rate of vegetables, and increase in harvest efficiency per unit area of vegetables, it falls under the requirements of the invention, such as novelty, inventive step, and practicality in industry. It is as follows.
(1) It is possible to reduce the nitrate nitrogen content of vegetables to 450 ppm or less.
(2) The culture medium can be easily collected and reused.
(3) Irrigation water can be saved.
(4) The EC / ph value of the culture solution can be accurately controlled.
(5) It is possible to increase land use efficiency by a multi-layer cultivation method.
(6) It is possible to greatly reduce the manpower required for cultivation.
(7) Pests caused by soil can be eradicated.

  The method for reducing the nitrate nitrogen content of vegetables according to one embodiment of the present invention employs hydroponics. It is characterized by using a water pipe for supply, recovery and storage of the culture solution. During the growth process of the vegetable, the culture solution in the distribution pipe is supplied to the root of the vegetable and absorbed, and when the ph value of the culture solution rises, As soon as the ph value is decreased and the EC value of the culture medium is increased, the EC value is decreased immediately, and the components of the culture medium are always maintained in an optimal state for absorption of vegetables. INDUSTRIAL APPLICABILITY The present invention has an inventive and practical utility such as saving irrigation water, eradicating drainage of hydroponic waste liquid and eradicating pests caused by soil, and exhibits excellent effects in agricultural cultivation technology.

  This embodiment is characterized by the use of a water distribution pipe, and unlike conventional hydroponics, the amount of the culture solution and water used can be effectively reduced (see [FIG. 5]). Moreover, although there exists an advantage that supply, collection | recovery, and reuse of a culture solution are advantageous, the culture solution required for the growth of a hydroponic vegetable is always supplied enough (refer to FIG. 1). The hydroponic cultivation technique of the present embodiment is based on a vinyl chloride resin tube and has a characteristic that it is convenient for collecting a culture solution. As a result, it is possible to eradicate the drainage of the waste liquid of the culture solution, and to effectively suppress the content of nitrate nitrogen accumulated in the shoots of vegetables to 450 ppm or less. In addition, since the hydroponic cultivation technique of this embodiment is based on a polyvinyl chloride resin tube that is an opaque material, sunlight does not directly irradiate the culture solution, so that various algae and bacteria are propagated in the culture solution. It is possible to prevent various algae and bacteria from competing for nutrients in the culture medium with vegetables during the cultivation process. As a result, alkaline substances secreted by algae and bacteria are further prevented from dissolving into the culture solution, the ph value of the culture solution is stably maintained, and the ph value increases so that the vegetable root absorbs the culture solution. (When the ph value is 5.5 to 6.5, the absorption efficiency of the root of the plant is the best).

As described above, the method for reducing the nitrate nitrogen content of vegetables according to this embodiment is different from conventional hydroponics and land cultivation. This embodiment has the following six features and can be said to be an advantage of improving agricultural cultivation technology.
(1) 70% savings on irrigation water (2) Eradication of drainage of hydroponic waste.
(3) Do not oxidize land.
(4) Pests caused by soil can be eradicated.
(5) The nitrate nitrogen content of vegetables can be reduced.
(6) It is possible to increase the speed at which vegetables grow.

  The first feature of this example is that it focused on the unreasonable situation that a good harvest can be expected in the end by supplying a large amount of irrigation water to crops in conventional agriculture. . A detailed analysis of where irrigation water is used in traditional agriculture revealed that not all of the irrigation water was absorbed by the crops. Actually, the amount of water required during the vegetable growth cycle is measured and statistically calculated. C. Was found to be sufficient. However, in the past, an average of about 200 C./day. C. -500C. C. (Varies depending on the drainage of soil) and wasted precious water resources. In conventional agriculture, irrigation water was swept into the basement at a rate of about 50% to 90% and wasted and wasted due to evaporation by solar heat. The waste of irrigation water in conventional agriculture is a problem that needs to be solved in the present situation where water shortages are becoming more serious every day. Vegetable cultivation according to this embodiment can save a large amount of irrigation water. The required water is only about 25% to 30% of the conventional water, and all the water and culture solution that the vegetables could not absorb can be recovered and reused.

  The second feature of the present example is that the adverse effect due to the drainage of waste liquid, which is a serious drawback of conventional hydroponics, has been solved. Conventional hydroponics culture solutions are difficult to prevent exposure to sunlight, and it is not possible to avoid the growth of algae and bacteria in the culture solution. This was one of the causes that caused the root rot of vegetables by rapidly decomposing (fermenting) the nitrates and raising the temperature of the culture solution. For this reason, waste liquids that can no longer be used often run down into rivers, but replacing them with new culture liquids has become a common part of hydroponics, which is a major cause of oxidizing the water quality of rivers. It has become. For the above reasons, the agricultural management organization of the Taiwan government does not prohibit hydroponic cultivation by law, but does not recommend it to farmers as the main cultivation method. In the hydroponic cultivation of this embodiment, the culture solution can be collected and reused, and there is no problem of the drainage of the waste liquid associated with the conventional hydroponic cultivation. In addition, since the culture solution can be recovered and reused, the production cost can be effectively reduced.

  The third feature of the present embodiment is to provide a cultivation method in which no chemical fertilizer is used in the soil and to prevent the soil from being oxidized or deteriorated. In soil cultivation, it is difficult to accurately control the amount of fertilizer used, and fertilizer is washed away from the soil due to irrigation water or rainwater. Often. This example provides the necessary culture solution according to the regular time, quantitative and different growth stages of vegetables. In addition, the hydroponics method of the present example supplies the culture solution directly to the roots of the vegetables, so it is not only economical, but also prevents the soil from being oxidized and deteriorated by excessive use of chemical fertilizers. Can do. Since the vegetable cultivation process of a present Example does not contact with soil at all, the soil contamination by a chemical fertilizer can be prevented completely.

The fourth feature of this example was that the conventional hydroponics lacked overall and specialized knowledge and had many undesirable after effects, but this example solved these problems. In the cultivation process of hydroponically cultivated vegetables, the roots are always immersed in the culture solution, so they cannot contact the air and cannot breathe. As a result, the nitrate nitrogen content inside the vegetables is much higher than that of soil-grown vegetables, which is one of the causes of excess nitrate nitrogen. Since hydroponically grown vegetables cannot breathe their roots, the enzymes inside the vegetables cannot provide enough oxygen to effectively metabolize nitrate nitrogen. In addition, the culture medium of hydroponics is often too high in concentration, and far exceeds the amount that can be loaded by the normal photosynthesis mechanism of hydroponic vegetables, and excessive amounts of nitrate groups (NO _{3) in} the stems and leaves of vegetables. -) Accumulates and cannot be converted into amino acids or ultimately synthesized into proteins. The nitrate group (NO _3- ) is one of the elements that the human body cannot metabolize. When a large amount of nitrate group (NO _3- ) is consumed and enters the digestive organs of the human body, the chemical action of digestive enzymes in the digestive organs Is converted to ammonium nitrite (NH ₄ NO ₂ ). Ammonium nitrite is considered to be a carcinogen and excessive consumption can adversely affect health. In addition, clinical medicine has shown that there is a possibility of blue baby syndrome. When an infant consumes a large amount of nitrate, the nitrate group (NO _3- ) enters the blood, causing hemoglobin to lose its ability to bind oxygen, causing the blood to become blue-purple, causing dyspnea, and in some cases choking Sometimes it ends up. Besides blue baby syndrome, it is one of the causes of gastrointestinal cancer. Ammonium nitrite (NH ₄ NO ₂ ) can destroy the red blood cells of the human body and even cause the cells to age rapidly. In developed countries, the regulation value of the nitrate content of vegetables has already been established to protect the health of consumers. In Germany, for example, spinach consumed by infants should not exceed 250 ppm. The intake of nitrate per kilogram of body weight proposed by WHO is 3.6 mg or less per day, and the safe residual amount of nitrate that a person with a body weight of 60 kilograms can consume per day should not exceed 500 ppm.

In EU, the regulation value of nitric acid content of edible vegetables has already been established, and is 2,000 to 3,000 ppm or less. China's regulatory limits are even stricter and are below 450 ppm. In Taiwan, vegetables produced in winter have a shortage of sunshine, excessive use of chemical fertilizers, and because they are supplied to the market, they are harvested before dawn. The residual amount of nitrate (NO _3- ) in vegetables is There are often even 3,000 to 4,000 ppm. Government authorities still do not show any attitude regarding the limit value of nitrate (NO _3- ) residue at this time. As a result, the regulation value adopted by the present invention is based on the world's strictest regulation value (450 ppm or less) in China, and the residual amount of nitrate group (NO _3- ) achieved by the present invention This is the only value in the world that realizes quantitative control of harmful substances contained in vegetables.
Note: Nitric acid group (NO ₃ −) concentration = Nitrate nitrogen (NO ₃ − −N) concentration × 4.43

This example is an improvement to the safety of the nitrate group (NO _3- ) of the supercharge accumulated in vegetables, and there is a possibility that conventional soil-cultivated and hydroponically grown vegetables may contain It is possible to prevent the remaining nitrate group (NO ₃ −) from being adversely affected by health. In general soil-cultivated vegetables, the roots have gaps between the soil and sand, so there is a flow of air and breathing freely. Oxygen (O ₂ ) taken into the vegetable by root respiration causes the vegetable to rapidly consume nitrate nitrogen (NO ₃ --N) and, as long as sunlight is sufficient, it is usually a nitrate group (NO _3). -) Is prevented from accumulating excessively (about 1,500 to 2,000 ppm), but it is observed irregularly at the time of harvest, and if photosynthesis is not sufficient, nitrate groups (NO ₃₎ in the foliage of soil-grown vegetables -) The content often exceeds (about 2,500 to 3,500 ppm). In conventional hydroponic vegetables, the roots are immersed in the culture solution for a long time and cannot directly breathe oxygen. Moreover, since the concentration of nitrates in the culture solution is high, the situation does not change even at the harvest time. This is different from the fact that soil cultivation has stopped using fertilizers long before the harvest of vegetables. The conventional hydroponic cultivation apparatus cannot control the supply of the culture solution in stages. Thus, excessive nitrate group in hydroponics vegetables (NO ₃ -) (approximately 3,000～4,500Ppm) had often contained. If the residual amount of nitrate nitrogen (NO ₃ --N) in vegetables is too high, the concentration of nitrate groups (NO _3- ) in the foliage will exceed 4,500 ppm. In this example, an experiment was actually performed by the control method of the present invention. Nitrate nitrogen (NO ₃ --N) content of sample vegetable (After sample vegetable is dried and chlorophyll is destroyed, nitrate nitrogen can be measured. The ratio of the weight of sample vegetable to the weight after drying is 4. As a result of adding control, the actual measured nitrate nitrogen (NO ₃ --N) content was only 358 ppm (refer to the National Chuoko University Agricultural and Natural Resource Academy analysis report) ) Below the regulation value for nitrate content of edible vegetables set by the EU (see regulation value for nitrate content of EU edible vegetables) and far below the nitrate content of conventional soil and organic vegetables. ing.
Note: See NIEA W415.52B for inspection methods.

Nitrogen (N ₂ ) required by conventional soil-grown vegetables is urea [CO (NH ₂ ) ₂ ], but the roots of plants usually cannot absorb urea directly (a small number). Except for rhizobial plants). Nitrogen (N ₂₎ elements, in the circulation of the nature, by bacteria or fungi in the soil first, the conversion of nitrogen in the urea [CO (NH _{2) 2]} a (N ₂₎ to ammonia (NH ₃₎ or nitrates Thereafter, ammonia (NH ₃ ) or nitrates are further decomposed into nitrite groups (NO ₂ ) through fermentation of nitrifying bacteria. Finally, the nitrifying bacteria again undergoes a second fermentation decomposition with respect to the nitrite group (NO ₂ ), and finally is converted into a nitrate group (NO ₃ −). After conversion, the nitrogen (N ₂ ) element in urea [CO (NH ₂ ) ₂ ] is only completely decomposed into nitrate groups (NO _3- ) and is absorbed by plant roots, and nitrate groups ( NO ₃ -) and then converted to an amino acid (amino acid) and carbon dioxide (CO2), finally, the amino acid (amino acid) is synthesized vegetables useful protein (protein). The mechanism of the conversion is that urea [CO (NH ₂ ) ₂ ] is first decomposed (fermented) by bacteria or fungi to become ammonia (NH ₃ ), and decomposed several times (fermented) by special bacteria in the soil. (NH ₃ ) is converted to nitrate groups (NO _{3 —} ). It becomes nitrate group (NO3-), finally absorbed into vegetables, converted to amino acid, and finally, by photosynthesis of vegetables, amino acids are synthesized into useful proteins inside the roots of vegetables. To do. In nature, some rhizobia plants can directly absorb and utilize natural ammonia (NH ₃ ) and nitrogen in the air (N 2) by the “nitrogen-fixing bacteria” community that parasitizes in the nodules. A chemical process in which ammonia (NH ₃ ) is absorbed by plants is referred to as nitrification, and its chemical reaction formula is as follows.
[(NO ₄ +) → (Nitrite Bacteria Degradation) → (NO ₂ −) → (Nitrification Bacteria Decomposition) → (NO ₃ −)]

The culture solution (fertilizer) used by conventional hydroponics is nitrogen, phosphorus, potassium, calcium, sulfur, and the like. Nitrogen is mainly sourced from nitrates such as calcium nitrate [Ca (NO ₃ −) ₂ ] and potassium nitrate K (NO ₃ ) prepared in the culture solution. Hydroponically grown vegetable roots are soaked directly in the culture for a long period of time and continue to absorb components such as nitrate groups (NO ₃ −) and cannot be effectively metabolized. The nitrogen (NO ₃ --N) content is necessarily very high. As a solution to this problem, it is possible to appropriately control the concentration of nitrate groups (NO ₃ −) in the culture solution and to set the supply amount at each growth stage. Adjust the supply and concentration of the culture in a timely manner depending on the amount of sunlight, the temperature, or the difference in the vegetable growth process. For example, under conditions where sunny sunshine hours are long, a culture solution with a slightly higher nitrate group (NO ₃ −) concentration is provided to promote fast growth of vegetables. This is because active photosynthetic action can reduce nitrate groups (NO _3- ) absorbed by vegetables to amino acids and synthesize them into proteins. Conversely, if the weather is unsatisfactory, the concentration of nitrate groups (NO _3- ) in the culture solution will be lowered, and nitrate groups (NO _3- ) will remain excessively in the vegetables due to insufficient photosynthesis. prevent. When nitrate groups (NO _3- ) are ingested by the human body, they act on digestive organs and digestive enzymes, and then are converted to ammonium nitrite (NH ₄ NO ₂ ), which is harmful to the human body. The present invention solves the above-mentioned problems of hydroponically grown vegetables. For a few days before the harvest of vegetables, the supply of culture fluid (nitrates) is completely interrupted and only water is supplied so that the vegetables can maintain their basic metabolism. This is the “culture liquid supply interruption cultivation method” of the present embodiment. The vegetable is metabolized and the nitrate group (NO _3- ) accumulated inside the vegetable is forcibly reduced to an amino acid before the harvest date. In other words, vegetables are sufficiently photo-synthesized (total amount of sunshine is 900,000 LUX. Or more), and amino acids in vegetables are converted into proteins, so that the nitrate groups ( The situation where the NO ₃ −) content is excessively high can be fundamentally solved. The reason why the content of nitrate groups (NO ₃ −) in commercially available vegetables is excessively high is mainly because vegetables absorb nitrate groups (NO ₃ −) excessively. In addition, the lack of time or activity of photosynthesis (6CO ₂ + 6H ₂ O → C ₆ H ₁₂ O ₆ + 6O ₂ ↑) carried out by the vegetable over the long period of time prevents the vegetable from making enough ATM enzymes. An important cause is that the absorbed nitrate group (NO ₃ −) could not be smoothly converted into an amino acid or synthesized into a protein. This is because vegetables are quickly harvested before consuming accumulated nitrate groups (NO ₃ −) to convert them into amino acids or synthesizing them into proteins.

  As described above, the present invention hydroponically cultivates vegetables with a culture solution containing nitrate nitrogen, grows the vegetables to some extent, and then hydroponically cultivates the vegetables only with water for a certain period before harvesting the vegetables. By cultivating, it is possible to provide a low nitrate nitrogen vegetable that consumes most of the nitrate nitrogen remaining inside the vegetable and does not adversely affect the human body.

  Hereinafter, the cultivation method of the low nitrate nitrogen vegetable of this invention is demonstrated based on drawing about embodiment of this invention. FIG. 1 is a schematic view showing a system of a method for controlling the nitrate nitrogen content of vegetables according to an embodiment of the present invention. As shown in FIG. 1, the present invention is a system that applies quantitative control to specific components of vegetables, and includes a culture solution supply and circulation system 1 and a hydroponic cultivation unit 2.

  FIG. 2 is a schematic view showing a culture solution supply and circulation system according to an embodiment of the present invention. The culture solution supply and circulation system 1 supplies and circulates the culture solution to the vegetables cultivated in the hydroponic cultivation unit 2. First, the culture solution supply and circulation system 1 constantly detects the EC value and ph value of the vegetable culture solution in the hydroponic cultivation unit 2, and adjusts the EC value and ph value of the culture solution as necessary. 2. Give the vegetables in 2 optimal and adequate nutrition, grow quickly and increase the harvest efficiency per unit area. After the vegetables are grown to some extent, that is, for a certain period before harvesting (72 hours in this embodiment), the supply and circulation system 1 of the culture solution collects the culture solution and provides only water. To make a basic metabolism of the vegetables. If the vegetables in the hydroponic cultivation part 2 are sufficiently photo-synthesized and the nitrate nitrogen accumulated in the stalks and leaves of the vegetables is consumed quickly, healthy-oriented low nitrate nitrogen vegetables can be cultivated smoothly. .

  The culture solution supply and circulation system 1 includes a culture solution storage tank 11, an irrigation storage tank 12, a culture solution pressurization pump 13, a culture solution recovery pump 14, a culture solution adjustment pump 15, an EC / ph value detection control device 16, and a UV. An ultraviolet germicidal lamp 17 and a microfilter 18 are provided. A culture fluid level control device 112 is disposed above the culture fluid storage tank 11, and the function of the culture fluid level control device 112 is necessary for recovering the culture fluid by controlling the capacity of the culture fluid storage tank 11. Secure space. A culture solution control valve 111 is disposed below the culture solution storage tank 11, and the culture solution control valve 111 is a valve for supplying the culture solution. A culture medium pressurizing pump 13 is disposed between the culture medium storage tank 11 and the culture medium supply pipe 21, and the function of the culture medium pressurizing pump 13 is to apply pressure to the culture medium and pass it through the microfilter 18. After filtering impurities, they are sent to the porous hydroponic tube 22 and used to grow vegetables. An irrigation water level control device 122 is disposed above the irrigation water storage tank 12, and the function of the irrigation water level control device 122 is to control the normal capacity of the irrigation water storage tank 12. An irrigation control valve 121 is disposed below the irrigation storage tank 12, and the irrigation control valve 121 is a valve for supplying irrigation. When the irrigation control valve 121 is set to ON, the culture solution control valve 111 is also set to OFF, the porous hydroponic tube 22 supplies water to the vegetables, helps the vegetables to perform photosynthesis, and accumulates in the foliage. Consumed nitrate nitrogen is consumed. On the contrary, the culture solution is supplied to the porous hydroponics tube 22 to grow the vegetables quickly. The culture solution recovery pump 14 applies pressure to the culture solution circulated from the culture solution recovery tube 23, passes the UV ultraviolet sterilization lamp 17, performs sterilization treatment, and then recovers it to the culture solution storage tank 11 and re-injects it. Prepare for use. An EC / ph value detection control device 16 is arranged outside the culture solution storage tank 11, and an EC / ph value detection line 165 and a culture solution storage tank are used to constantly detect changes in the EC value and ph value of the culture solution. 11 outlets are connected. A signal is transmitted through the EC / ph value control line 166, the EC solution container 161 or the ph solution container 162 is operated, and the EC value and ph value of the culture solution are adjusted. When the EC liquid container 161 or the ph liquid container 162 receives a signal transmitted from the EC / ph value detection control device 16, the EC liquid container 161 or the ph liquid container 162 operates, and the EC liquid passes through the EC liquid injection pipe 163 and the ph liquid passes through the ph liquid injection pipe. The medium is fed into the culture medium storage tank 11 via 164 and mixed with the culture medium, and the EC value and ph value of the culture liquid are always maintained at the set levels. When the EC value or the ph value rises, the culture solution adjustment pump 15 operates to send water from the irrigation storage tank 12 to the culture solution storage tank 11 to lower the EC value or ph value of the culture solution. When the water in the irrigation storage tank 12 is insufficient, the irrigation control valve 123 is turned on, and the water is stored in the irrigation storage tank 12 to prepare for necessity.

  FIG. 3 is a schematic diagram showing a hydroponic cultivation unit according to an embodiment of the present invention. The hydroponic cultivation unit 2 includes a culture solution supply tube 21, a porous hydroponic cultivation tube 22, a culture solution recovery tube 23, and an artificial lighting device 24. The functions of the culture solution supply pipe 21 and the culture solution equilibrium pipe 211 are to quickly fill the culture solution supplied from the culture solution pressurizing pump 13 up to the culture solution set liquid level in the porous hydroponic cultivation tube 22, and quickly feed vegetables. It is to grow. For a certain period of time before the harvest of vegetables, the culture medium pressurizing pump 13 is similarly used to supply water to the space that is originally filled with the culture medium, to cause the vegetables to undergo basic metabolism, to perform photosynthesis, It quickly consumes nitrate nitrogen accumulated in the foliage. The porous hydroponic tube 22 has a plurality of circular cultivating holes 221 that form a straight line and are arranged in a line at regular intervals, and the roots of vegetables are passed through one of the circular cultivating holes 221 that are arranged in a line. Then, it is placed in the porous hydroponics tube 22 to absorb the culture solution and grow rapidly. For a certain period of time before harvesting, only water is absorbed, allowing the vegetable to carry out basic metabolism, to fully perform photosynthesis, to quickly consume nitrate nitrogen accumulated in the foliage of the vegetable, The content is suppressed to 450 ppm or less. Within a certain period of time before harvesting when the supply of the culture solution was stopped, the weather such as cloudy and rainy continued, severe sunshine shortage, and the cumulative amount of sunshine per day in which vegetables are bathed is 300,000 LUX. / Hr. Otherwise, the artificial lighting device 24 is activated, and the amount of sunlight of the porous hydroponic cultivation tube 22 is set to 300,000 LUX. / Hr. Increase to. The operation of the artificial lighting device 24 is performed by the optical sensor 241 measuring the amount of sunlight and transmitting a signal to the artificial lighting device 24 via the optical signal transmission line 242 for calculation. The amount of sunshine is calculated at 12 hours during the day, but if it is insufficient, the amount of sunshine is replenished using 12 hours at night (15,000 LUX./hr. In this embodiment). The power is supplied to the high-power mercury lamp group 244 via the electric wire 243, the high-power mercury lamp group 244 is operated, the insufficient amount of sunlight is supplemented, the energy of artificial lighting is absorbed by the vegetables, and the nitrate state accumulated in the foliage The quick consumption of nitrogen allows daily harvesting of low nitrate nitrogen vegetables that are healthy and that are not affected by weather changes and that cannot be produced in a natural environment or by conventional techniques. Artificial lighting systems are operating under special bad weather conditions, and only when the amount of sunshine on the day is insufficient, the artificial lighting system is inadvertently replenished and wastes valuable energy. Absent. The culture medium recovery tube 23 is connected to the culture medium recovery pump 14 via the culture medium recovery valve 231, and the culture medium recovery valve 231 is always set to the on state so that the culture medium recovery, EC value, and ph value are set. Replenish the adjustment solution. When the system is not set to circulation, the culture medium recovery valve 231 is turned off and the drain valve 232 is turned on for drainage, and the water used in the porous hydroponic tube 22 is a water treatment device. (Not in the application content of the present invention) and reused after disinfection, sterilization and filtration.

The method for controlling the nitrate nitrogen content of vegetables according to the present embodiment is an advanced invention of technology utilizing the laws of nature, and the mechanism is employed in the claims of the present invention. The hydroponic cultivation system uses the broth supply interruption method to allow photosynthesis to occur for a certain period before harvesting the vegetables and to sufficiently consume nitrate nitrogen accumulated in the foliage of the vegetables. In addition, the culture solution is collected within a certain period before the vegetables are harvested, and only water is supplied to the vegetables. The “culture solution supply stop method” of the present invention forcibly consumes nitrate nitrogen accumulated in the foliage of vegetables, and its mechanism is as follows.
(Nitrate group NO _3- ) ((Conversion of photosynthesis) ((Amino acid) ((Synthesis of photosynthesis) ((Protein protein)
Note: The total amount of sunshine during the culture broth supply interruption method of this embodiment is 900,000 LUX. That's it. The period of the culture supply interruption method is 72 hours before harvesting. The nitrate nitrogen content accumulated in the stems and leaves of the produced vegetables is 358 ppm. See NIEA W415.52B for inspection methods. The inspection organization is National Chukoh University, Faculty of Agriculture and Natural Resources.

  Although preferred embodiments of the present invention have been disclosed as described above, they are not intended to limit the present invention in any way, and anyone skilled in the art is within the spirit and scope of the present invention. Various changes and modifications can be made. Therefore, the scope of protection of the present invention is based on the contents specified in the claims.

It is the schematic diagram which showed the system of the control method of the nitrate nitrogen content of vegetables by one Embodiment of this invention. It is the schematic diagram which showed the supply and circulation system of the culture solution by one Embodiment of this invention. It is the schematic diagram which showed the hydroponic cultivation part by one Embodiment of this invention. The side view of the porous hydroponic cultivation tube by one Embodiment of this invention. The comparison figure of the water demand of one Embodiment of this invention and the conventional hydroponics.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Supply and circulation system of culture solution 11 Culture solution storage tank 111 Culture solution control valve 112 Culture solution liquid level control device 12 Irrigation storage tank 121 Irrigation control valve 122 Irrigation water level control device 13 Culture solution pressurization pump 14 Culture solution collection pump 15 Culture liquid adjustment pump 16 EC / ph value detection controller 161 EC liquid container 162 ph liquid container 163 EC liquid injection pipe 164 ph liquid injection pipe 165 EC / ph value detection line 166 EC / ph value control line 17 UV ultraviolet germicidal lamp 18 Microfilter 2 Hydroponic cultivation section 21 Culture fluid supply pipe 211 Culture fluid equilibrium tube 22 Porous hydroponic culture tube 221 Multiple circular cultivation holes 23 arranged in a row 23 Culture fluid recovery tube 231 Culture fluid recovery valve 232 Drain valve 24 Artificial lighting Device 241 Optical sensor 242 Optical signal transmission line 243 Electric wire 244 High power mercury lamp group

Claims (12)

A vegetable cultivated by hydroponics,
Feeding and growing the culture solution, stopping the supply of the culture solution prior to harvesting, consuming the nitrate nitrogen accumulated in the plant body by cultivating with water, the content of nitrate nitrogen is 450 ppm or less Reduced to,
A low nitrate nitrogen vegetable. In vegetable cultivation by hydroponics,
After growing the vegetables with the culture solution and cultivating for a certain period, the supply of the culture solution is stopped and recovered prior to harvesting,
Instead, water is supplied and photosynthesis is performed to consume nitrate nitrogen accumulated in the plant body.
A method for cultivating a low nitrate nitrogen vegetable, wherein the content of nitrate nitrogen is reduced to 450 ppm or less.   Low nitrate nitrogen, comprising a culture solution supply and circulation system and a hydroponic cultivation unit that supplies and collects a culture solution to a hydroponic cultivation unit and supplies and recovers water instead of the culture solution Vegetable cultivation system.   The culture solution supply and circulation system includes a culture solution storage tank, an irrigation storage tank, a culture solution pressurization pump, a culture solution recovery pump, a culture solution adjustment pump, an EC / ph value detection control device, a UV ultraviolet germicidal lamp, and a microfilter. The low nitrate nitrogen vegetable cultivation system of Claim 3 characterized by the above-mentioned.   4. The low nitrate nitrogen according to claim 3, wherein the hydroponic cultivation unit includes a culture solution supply tube, a porous hydroponic tube having a hole for planting a vegetable, a culture solution recovery tube, and an artificial lighting device. Vegetable cultivation system.   5. The low nitrate nitrogen vegetable cultivation system according to claim 4, wherein the culture solution storage tank includes a culture solution control valve and a culture solution level control device.   The low nitrate nitrogen vegetable cultivation system according to claim 4, wherein the irrigation storage tank includes an irrigation control valve and an irrigation water level control device.   The EC / ph value detection control device includes an EC liquid container, a ph liquid container, an EC liquid injection pipe, a ph liquid injection pipe, an EC / ph value detection line, and an EC / ph value control line. 4. The low nitrate nitrogen vegetable cultivation system according to 4.   The low nitrate nitrogen vegetable cultivation system according to claim 5, wherein the culture solution supply tube includes a culture solution equilibrium tube.   The low nitrate nitrogen vegetable cultivation system according to claim 5, wherein the porous water cultivation tube includes a plurality of circular cultivation holes arranged in a row.   6. The low nitrate nitrogen vegetable cultivation system according to claim 5, wherein the culture solution recovery tube includes a culture solution recovery valve and a drain valve.   6. The low nitrate nitrogen vegetable cultivation system according to claim 5, wherein the artificial lighting device includes an optical sensor, an optical signal transmission line, a power source, and a high output mercury lamp group.

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