WO2019139031A1 - Nutrient liquid cultivation method for cultivated plant, and culture solution for nutrient liquid cultivation - Google Patents

Abstract

The present invention is a method for cultivating during the period from seeding to harvest using a culture liquid that includes the fertilizer components necessary for the maturation of a plant body. The method is characterized in that, when the abovementioned period is divided into a germination period in which a seedling-raising device is used for cultivation from seeding to germination, a seedling-raising period in which the seedling-raising device is used for cultivation until a seedling that has germinated at the seedling-raising device has grown to a prescribed size, and a maturation period in which the seedling that has been grown to the prescribed size is transplanted from the seedling-raising device to a maturation device and cultivated until being harvested from the maturation device, a seedling-raising culture solution that has a magnesium ion concentration of 24–120 ppm and a nitrate nitrogen concentration of 4–50 ppm is used during the seedling-raising period, or a maturation culture solution that has a magnesium ion concentration of 48–120 ppm and a nitrate nitrogen concentration of 150–200 ppm is used during the maturation period.

Description

Hydroponic culture method of cultivated plants and culture solution for hydroponic culture

TECHNICAL FIELD The present invention relates to a method for hydroponic cultivation of cultivated plants such as vegetables and florets and a culture solution for hydroponic culture used for the same.

Magnesium is an element involved in protein synthesis (association of ribosome particles), DNA synthesis, RNA synthesis, regulation of 300 or more enzyme activities, stabilization of ATP, and is a constituent element of chlorophyll, and so on. It is known to be an essential element to support.

In plants, the site where cells divide is localized to the shoot apical and root end meristems, so in order to maintain high cell division activity, relatively high concentrations of magnesium are supplied to those tissues It needs to be done. In particular, DNA polymerase directly involved in cell division has been found to require a relatively high concentration of magnesium ion for its catalytic activity (for reference, the optimum concentration of magnesium required for the catalytic activity of Taq DNA polymerase) Is 4 mM (= 96 ppm)). Therefore, if the supply of magnesium to the shoot apical and root end meristems is insufficient, the cell division rate will be slow and thus the growth rate as a plant individual will be reduced. Conversely, if magnesium is sufficiently supplied to the above-mentioned tissue, the growth rate of the individual plant will be increased.

Magnesium is absorbed from the roots. Much of the magnesium absorbed from the roots is not transported directly to the shoot apical and root end meristems, but is first transferred to the leaves by transpirational flow, and then travels on a phloem flow to shoot apical meristems And supplied to the root end meristem. Since the phloem flow is from the side with high solute concentration to the side with low solute concentration, the magnesium concentration in the leaf on the supply side (source side) needs to be higher than the magnesium concentration required in the meristem (sink side) It becomes. That is, in order to maintain high cell division activity (and thus high growth rate), a difference between the magnesium concentration on the sink side and that on the source side is required.

Hydroponic cultivation is one of the cultivation methods of cultivation plants such as vegetables and flower buds (for example, Patent Document 1). Although there are horticultural test place prescription, Yamazaki prescription, Otsuka House A prescription etc. in the culture solution prescription used in hydroponic culture, the component composition of these prescriptions are all three elements essential for the growth of cultivated plants (nitrogen, It is configured by combining appropriate fertilizer components according to the type of the cultivated plant to be targeted, centering on phosphoric acid and potassium). Magnesium is one of the fertilizer components contained in the culture solution formulation next to three factors because it greatly contributes to the growth of plants.

The composition of the fertilizer component of each formulation is determined empirically with reference to the analysis results of cultivated plants and the absorption rate from the root regarding each fertilizer component, and it is considered as a composition by which normal growth is confirmed There is. In particular, nitrogen, phosphoric acid and potassium, which are essential three elements, have long been used as fertilizer components of various types of plants. Among the hydroponics operators, there was a strong belief that the conventional formulation was the best one empirically and there was no room to try any other formulation, so the conventional culture fluid formulation was not reviewed It is the fact that it continues to be used.

JP 2003-174827 JP, 2017-221177, A

The present invention has been made in view of the above circumstances, and an object thereof is a culture solution for hydroponic culture having a component composition effective for promoting the growth of cultivated plants such as vegetables and florets, and a hydroponic culture method using the same. To provide.

The present invention has been found as a result of reviewing culture fluid formulations conventionally used in hydroponic cultivation of vegetables with the goal of improving the quality of vegetables and shortening the growing period (cultivation period) of vegetables. It is a thing. Although various indexes can be considered as indicators representing the quality of vegetables, the present inventors first aimed at increasing antioxidant components and decreasing residual nitrate. In addition, we aimed to shorten the growth period by 30 to 50%. As a result, the magnesium ion contained in the culture solution for nutrient solution culture promotes the growth of vegetables, and furthermore, depending on the time of growth of vegetables, the presence of nitrate ion contained in the culture solution is the growth by magnesium ion It has been found that the promoting action is reduced, and the present invention has been completed.

That is, the first aspect of the method for cultivating cultivated plants according to the present invention is a method for cultivating using a culture solution containing a fertilizer component necessary for growth of a plant during a period from sowing to harvesting.
A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. When a seedling grown to a predetermined size is transplanted from the above-mentioned seedling-growing device to a growing device and divided into growing periods which are periods until cultivation is carried out by the growing device,
It is characterized by using a culture solution for raising seedlings wherein the concentration of magnesium ion is in the range of 24 ppm to 120 ppm and the concentration of nitrate nitrogen is in the range of 4 to 50 ppm in the growing period.

Cultivated plants generally refer to vegetables, florets, fruits, feed crops and the like, but in the present invention, cultivated plants for which hydroponic cultivation of vegetables, florets and the like are carried out due to their nature Point to. The seedling-growing device may be any device capable of using the culture solution to germinate a cultivated plant from seeds and grow the seedling to a predetermined size. Further, the growing apparatus may be any apparatus as long as it can grow a seedling grown to a predetermined size in the seedling-growing apparatus to a harvestable state using a culture solution. Furthermore, the nutrient solution cultivation method according to the present invention is applicable to any of nutrient broth cultivation of fixed medium cultivation, hydroponic cultivation and spray cultivation. In the present specification, "ppm" represents the concentration by weight.

It should be noted in the present invention that the concentration of nitrate nitrogen contained in the culture medium for raising seedlings is lower than that in the conventional formulation. The concentration of nitrate nitrogen is in the range of 60 to 240 ppm in a conventional culture solution for nutrient solution cultivation generally used for hydroponic cultivation of vegetables and florets, and in particular, for fruits and vegetables, leaf vegetables and floriculture In the cultivation method of the cultivated plant according to the present invention, the concentration of nitrate nitrogen in the culture solution (EC = 1.8) according to Otsuka A prescription (OAT AGRIO CO., LTD.) Widely used for hydroponics is 161 ppm. The concentration of nitrate nitrogen in the culture broth for raising seedlings is 4 to 50 ppm, which is lower than the conventional formulation. In addition, the concentration of magnesium ion in the culture solution for raising seedlings is in the range of 24 ppm to 120 ppm. Since the concentration of magnesium ion in the culture solution for nutrient solution cultivation generally used in the nutrient solution cultivation of vegetables and florets is in the range of 10 to 40 ppm, it is used in the cultivation method of the cultivation plant according to the present invention The value near the lower limit of the magnesium ion concentration range of the culture solution for raising seedlings to be grown is included in the concentration range of the conventional formulation.

However, in the present invention, since the concentration of nitrate nitrogen contained in the culture solution for raising seedlings is lower than that in the conventional formulation, even if the concentration of magnesium ion is similar to that in the conventional formulation, plant growth is promoted more than in the conventional formulation. Furthermore, when the concentration of magnesium ion is higher than that of the conventional formulation, the growth promoting action is increased.
It is considered that this is because cell division progressed in the meristem by reducing nitrate ion contained in the culture solution. That is, when the culture solution contains a large amount of nitrate ions, much energy is consumed for absorption and reduction of nitric acid, which is a high priority for plants, and energy required for cell division is insufficient. Because it is suppressed, the action of promoting cell division by magnesium ions taken into plants is not exerted. However, when cell division progresses in the meristem, cell division is accelerated by magnesium ions incorporated into plants, and as a result, growth is promoted.

The magnesium ion incorporated into the plant acts independently on the shoot apical and root end meristems to promote the growth and root elongation of the aerial part. At this time, the optimum concentration of the magnesium ion which exerts the growth promoting action of the aerial part and the optimum concentration of the magnesium ion which exerts the action of promoting the elongation of the root are different.
Therefore, it is preferable to adjust the concentration of magnesium ion in the culture solution for raising seedlings according to cultivated plants (for example, leafy vegetables) for which growth promotion in the above-ground part is desired or cultivated plants (for example, root vegetables) for which root growth is desired. Further, not only the concentration of magnesium ion but also the concentration of nitrate nitrogen may be adjusted according to the type of cultivated plants.

By the way, since photosynthesis becomes active when plants grow large, energy required for cell division does not run short even if energy is consumed for absorption and reduction of nitric acid. In addition, since nitrogen is a fertilizer component necessary for the growth of plant leaves, it is desirable that the culture solution used in the growth period contains a sufficient amount of nitrogen.

Therefore, a second aspect of the method for producing a hydroponic solution of cultivated plants according to the present invention is a method of cultivating using a culture solution containing a fertilizer component necessary for plant growth during a period from sowing to harvesting.
A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. When a seedling grown to a predetermined size is transplanted from the above-mentioned seedling-growing device to a growing device and divided into growing periods which are periods until cultivation is carried out by the growing device,
In the growing period, a growth medium having a concentration of magnesium ion in the range of 48 ppm to 120 ppm and a concentration of nitrate nitrogen in the range of 150 ppm to 200 ppm is used.
The above-mentioned concentration range of nitrate nitrogen is a range where it is empirically considered that the growth efficiency of plants is excellent (that is, the concentration range of the conventional formulation). On the other hand, the above-mentioned concentration range of magnesium ion is a range of concentration higher than the concentration range of the conventional prescription. By setting the concentration range of nitrate nitrogen and magnesium ions in the culture solution to the above concentration range, the growth period can be shortened as compared with the case of using the culture solution of the conventional formulation.

In addition to magnesium ions and nitrate nitrogen, elements necessary for the growth of cultivated plants in the growing period are contained in the above-mentioned culture solution for raising seedlings and the culture solution for growing as required. For example, the culture solution for raising seedlings and the culture solution for growth may contain phosphorus and potassium which are three elements of fertilizer other than nitrogen. In addition to nitrate nitrogen, ammonia nitrogen may be contained. Furthermore, ions of metal elements other than magnesium (such as calcium, boron, iron, zinc, manganese, copper, selenium, nickel, molybdenum, etc.) may be contained.

Moreover, although the culture solution for raising seedlings may be used in the whole period of a raising seedling period, you may use it only in a partial period. Similarly, the culture broth for growth may be used for the entire growth period, but may be used for only a part of the growth period.

In addition, since magnesium ions absorbed from roots of cultivated plants are transported to the leaves by transpiration flow, an increase in the content of magnesium contained in the leaves can be expected. Therefore, the cultivation method according to the present invention is effective when cultivating a plant that is a leafy vegetable whose leaves are edible and in which an increase in the content of magnesium contained in the leaf is desired.

Examples of plants for which it is desired to increase the content of magnesium contained in leaves include cruciferous vegetables including Komatsuna. Although Komatsuna originally has a high content of magnesium, the magnesium content can be further increased by using the method of hydroponic cultivation according to the present invention. In addition to Komatsuna, various leafy vegetables such as chima sanchu, cos lettuce, green batavia, etc. are cultivated using the above-mentioned cultivation method to obtain leafy vegetables having an increased amount of magnesium ions contained in the leaves. Can.

Moreover, the third aspect of the method for producing a hydroponic solution of cultivated plants according to the present invention is a method of cultivating using a culture solution containing a fertilizer component necessary for plant growth during a period from sowing to harvesting.
A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. Seedlings grown to a predetermined size are transplanted from the seedling raising apparatus to a growing apparatus, and the growing apparatus is a growing period which is a period during which a predetermined time before growing is harvested, the growing apparatus from the harvesting time When divided into the pre-harvest period which is the period of cultivation from the predetermined time before to the harvest time,
Using a culture solution for raising seedlings wherein the concentration of magnesium ions is in the range of 24 ppm to 120 ppm and the concentration of nitrate nitrogen is in the range of 4 to 50 ppm during the raising period;
In the pre-harvest period, it is characterized by using a calcium-containing nutrient solution containing no nitrogen and further irradiating visible light having a wavelength of 490 nm or less.

Moreover, the 4th aspect of the nutrient solution cultivation method of the cultivation plant which concerns on this invention is a method of cultivating using the culture solution containing the fertilizer component required for the growth of a plant for the period from sowing to harvest,
A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. Seedlings grown to a predetermined size are transplanted from the seedling raising apparatus to a growing apparatus, and the growing apparatus is a growing period which is a period during which a predetermined time before growing is harvested, the growing apparatus from the harvesting time When divided into the pre-harvest period which is the period of cultivation from the predetermined time before to the harvest time,
In the growing period, a growth medium having a concentration of magnesium ion in the range of 48 ppm to 120 ppm and a concentration of nitrate nitrogen in the range of 150 ppm to 200 ppm is used.
In the pre-harvest period, it is characterized by using a calcium-containing nutrient solution containing no nitrogen and further irradiating visible light having a wavelength of 490 nm or less.

In the cultivation methods of the third and fourth aspects, it is preferable that the light intensity including visible light having a wavelength of 490 nm or less is 80 μmol or more per square meter.

The germination period, the nursery period, and the growth period in the cultivation methods of the third and fourth aspects are the same as those periods in the cultivation methods of the first and second aspects. Also, the pre-harvest period in the third and fourth aspects is about 1 day to 5 days.
The cultivation methods of the third and fourth aspects are different from the cultivation methods of the first and second aspects in that a pre-harvest period is provided. As described in detail below, hydroponic cultivation in the pre-harvest period is carried out to increase the content of antioxidant components contained in harvested cultivated plants. By providing the pre-harvest period, the cultivation period of the cultivation methods of the third and fourth aspects is longer than the cultivation period of the cultivation methods of the first and second aspects. However, in the cultivation method of the third aspect, by using the culture solution for raising seedlings in the raising period, the growing period is shortened as compared with the case of performing nutrient solution cultivation in the raising period using the culture solution of the conventional prescription. Moreover, in the cultivation method of the 4th aspect, the growth period is shortened compared with the case where the nutrient solution cultivation of a growth period is performed using the culture solution of the conventional prescription by using the said culture solution for growth in a growth period. In any of the cultivation methods of the third aspect and the fourth aspect, since the extension due to the pre-harvest period is offset by the shortening of the growth period, the whole cultivation period is the same as the cultivation period by the conventional cultivation method Or, it can be shortened than the cultivation period by the conventional cultivation method.

In the cultivation method of the first aspect of the present invention, the concentration of nitrate nitrogen is made lower than that of the conventional prescription culture solution for nutrient solution cultivation, and the concentration of magnesium ion is the same as that of the culture formulation for nutrient solution cultivation of the conventional formulation. By carrying out hydroponic cultivation for the seedling raising period using the raising liquid for raising seedling that has been raised to a certain extent or more, it is possible to effectively exert the promoting effect of growth and root elongation of the above-ground part of the plant by magnesium ion it can. In particular, when the concentration of magnesium ion contained in the culture solution is higher than the concentration of magnesium ion contained in the culture solution of the conventional formulation, a plant containing a large amount of magnesium can be produced.

In the cultivation method according to the second aspect of the present invention, the concentration of nitrate nitrogen is set to a concentration range in which the growth efficiency of the plant is excellent, and the concentration of magnesium ions is higher than the conventional culture broth for nutrient solution cultivation. By performing hydroponic culture for the growth period using the culture solution for growth, the growth period can be shortened compared to the case of using the conventional culture solution for hydroponic culture. Moreover, since the growth of plants is promoted by increasing the concentration of magnesium ions, in addition to the growth promotion of plants, an effect of being able to create a plant rich in magnesium can be obtained.

In the cultivation methods of the third and fourth aspects of the present invention, in the cultivation methods of the first and second aspects, further, before harvesting, a nitrogen-free, calcium-containing nutrient solution is used and the wavelength is further added. Is a period (pre-harvest period) in which hydroponic cultivation is performed by irradiating visible light of 490 nm or less. By providing such a pre-harvest period, in the cultivation methods of the third and fourth aspects of the present invention, in addition to the effects obtained by the cultivation methods of the first and second aspects described above, glutathione is represented by The effect of being able to produce the plant which contains many antioxidant ingredients is acquired.

Explanatory drawing of the cultivation period of the nutrient solution cultivation method which concerns on one Example of this invention. It shows the results of Experiment 1, and shows a state of growth two weeks after sowing of four types of vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) hydroponically grown using a culture solution having an Mg concentration of 12 ppm. Photo. It shows the results of Experiment 1, and shows the state of growth two weeks after sowing of four types of vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) hydroponically grown using a culture solution having an Mg concentration of 24 ppm. Photo. It shows the results of Experiment 1, and shows a state of growth two weeks after sowing of four types of vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) hydroponically grown using a culture solution having an Mg concentration of 36 ppm. Photo. It shows the results of Experiment 1, and shows a state of growth two weeks after sowing of four types of vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) hydroponically grown using a culture solution having an Mg concentration of 48 ppm. Photo. It shows the results of Experiment 1, and shows a state of growth two weeks after sowing of four types of vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) hydroponically grown using a culture solution having an Mg concentration of 96 ppm. Photo. The graph which shows the result of Experiment 1, and shows the relationship between the fresh weight of the aerial part (a) and the root (b) of Komatsuna, and the magnesium ion concentration in a culture solution. It is a figure which shows the result of Experiment 1, and shows the relationship between Mg density | concentration and the growth promotion effect of a root and an above-ground part. A photograph showing the results of Experiment 2, showing a picture of the growth of Komatsuna grown by hydroponic culture in a nursery using a culture solution having an Mg concentration of 48 ppm and a nitrate N concentration of 3.05 to 78.2 ppm (a )-(F). A photograph showing the results of Experiment 2, which is a photograph showing the state of growth of Komatsuna cultivated by hydroponic cultivation in a nursery using a culture solution having an Mg concentration of 12 ppm and a nitrate N concentration of 4.6 to 184 ppm. A photograph showing the results of Experiment 2, which is a photograph showing the state of growth of Komatsuna cultivated by hydroponic cultivation with a nursery apparatus using a culture solution having an Mg concentration of 24 ppm and a nitrate N concentration of 4.6 to 184 ppm. A photograph showing the results of Experiment 2, which is a photograph showing the state of growth of Komatsuna cultivated by hydroponic culture in a nursery using a culture solution having an Mg concentration of 48 ppm and a nitrate N concentration of 4.6 to 184 ppm. The figure which shows the result of experiment 2, and shows the relationship between N ^<+> density | concentration and the extension | extension promotion effect of a root. The graph which shows the result of experiment 3 and shows the growth amount of chimasangyu in a growth period. It is a graph which shows the result of Experiment 4 and shows the amount of growth of Chimasanchu in a growth period. It is a graph which shows the result of Experiment 5, and shows the growth amount of the chimasanthu in a growth period. The graph which shows the result of Experiment 6 and shows the growth amount of the chimasanthu during a growth period. The graph which shows the result of Experiment 7 and shows the growth amount of Komatsuna in a growth period. The graph which shows the result of Experiment 8 and shows the growth amount of Coss Lettuce in a growth period. The graph which shows the result of Experiment 9 and shows the growth amount of green batavia in a growth period. The figure which shows the result of Experiment 10, and shows Mg content and its increase multiple of four kinds of leafy vegetables (Chimasanthu, Komatsuna, Kos Lettuce, Green Batavia) harvested after 3 weeks of hydroponic culture with a growth apparatus . The graph which shows the result of Experiment 11 and shows the growth amount of Komatsuna in a growth period. The graph which shows the result of Experiment 12 and shows the growth amount of the green wave in a growth period. The graph which shows the result of Experiment 13, and shows the content of the antioxidant component of the ORAC value of Komatsuna of an experiment area and a comparison area. The graph which shows the result of Experiment 13, and shows the content of the ORAC value of a green batavia of an experiment area and a comparison area, and an antioxidant ingredient. Content of glutathione contained in vegetables obtained by ordinary cultivation methods. Shows the relationship between the amount of Ca in the culture solution and the harvested ORAC values of Komatsuna, Komatsuna purple and chimasanchu when hydroponically cultivated Komatsuna, purple and chimasanchu using the method described in Patent Document 2 Figure.

Hereinafter, although the cultivation method according to the present invention and the culture solution for nutrient solution cultivation will be described with reference to an example using vegetables, the present invention relates to cultivated plants capable of being subjected to nutrient solution cultivation of vegetables, florets etc. Applicable to the whole.

In the examples, leafy vegetables chimasanchu, komatsuna, kos Lettuce, green batavia, bok choy, leaf lettuce, sungiku, and green wave were used as vegetables. Chimasanthu, Kos Lettuce, Green Batavia, Leaf Lettuce, Sung chrysanthemum, Green Wave are the vegetables of the Asteraceae family, and Komatsuna, Ting Gin Sai are vegetables of the Brassicaceae family.

(1) Cultivation apparatus Seed raising apparatus: This apparatus comprises a container body in which a culture solution is stored, a plurality of seedling raising bases disposed thereon, a supply passage and a discharge passage of the culture solution connected to the container body, and a pump Supply and discharge of the culture solution to and from the container body is performed by the supply and discharge channels. Each nursery base has a hole for sowing, in which one seed is stored. The lower part of the nursery base is immersed in the culture solution, and the species placed in the hole is immersed in the culture solution. Among the cultivation periods of vegetables, a period of time from sowing to germination (germination period) and a period of time until germination to a predetermined size (sourcing period) of vegetables are used.

Growth apparatus: This apparatus comprises a container body in which a culture solution is stored, a plastic panel disposed on the container body, a supply and discharge passage of the culture solution connected to the container body, and a pump. ing. Similar to the seedling raising apparatus, supply and discharge of the culture solution to and from the container main body are performed by the supply and discharge channels of the culture solution. The panel has a number of holes, and the seedling base is disposed on each hole. The roots of plants grown on a nursery basis are immersed in the culture solution through the pores. Seedlings grown to a predetermined size by the above-described seedling-growing apparatus are transplanted to a growth apparatus, and are grown until harvest by the growth apparatus. That is, the growing apparatus is used during a growing period of vegetables (growth period) until the seedlings grown to a predetermined size are harvested.

(2) Preparation of culture solution In this example, Otsuka agritechno A prescription (hereinafter "Otsuka A prescription") is used as a culture solution as a standard prescription, and the culture solution by this Otsuka A prescription (hereinafter "Otsuka A prescription culture solution") The culture solution which changed the magnesium (Mg) concentration of Otsuka A prescription culture solution (hereinafter referred to as “Mg adjusted A prescription culture solution”), and the culture solution according to the inventor's own prescription (hereinafter “TO prescription culture solution ") Was used. The nitrogen (N) concentration and Mg concentration of Otsuka A prescription are shown in Table 1 below. In Table 1, ppm indicates a weight ratio. Also, although magnesium contained in the culture solution according to each formulation is present as ions (Mg ²⁺ ), in the present specification, both magnesium and magnesium ions are denoted as “Mg” for convenience.

In the Mg-adjusted A prescription culture solution, magnesium chloride was added to the A prescription culture solution to change the Mg concentration. In addition, a TO formulated culture solution was prepared according to the following procedure using the following drugs.

(2-1) Preparation of stock nutrient solution Two types of stock nutrient solutions were prepared. The composition of each stock nutrient solution is as follows.
<First stock nutrient solution>
・ KNO ₃ 5g / L
・ K ₂ SO ₄ 50 g / L
-Potassium phosphate 30g / L
・ EDTA-Fe (Na) 20 g / L
・ 10 mL / L of trace element solution
The trace element solution contains an element common to fertilizer components such as copper, zinc and manganese.

<Second stock nutrient solution>
・ Otsuka House No. 2 X g / L
· MgCl ₂ · 6 H ₂ O Y g / L (X + Y = 140 g / L)

(2-2) Preparation of TO Formulation Culture Solution Prepare a plurality of second stock solutions with different ratios of X and Y, and equal amounts of the second stock solution and one type of first stock solution. Culture solutions of various Mg concentrations were prepared by diluting each stock solution by about 150 times in addition to water.
For example, as shown in Table 2 below, three types of Otsuka House No. 2 containing 100 g / L, 80 g / L, 60 g / L, and 40 g / L, 60 g / L, and 80 g / L of MgCl ₂ · 6H ₂ O Prepare a second stock solution (No. 2-1 to 2-3). Then, after adding 67 mL each of the first stock nutrient solution and the second stock nutrient solution to about 9 L of water, water is added so that the total amount becomes 10 L. As a result, the Mg concentrations in the culture solution prepared using the first stock solution and the 2-1 to 2-3 stock solutions are 31.9 ppm, 47.8 ppm and 63.7 ppm, respectively. The nitrate N concentration is 4.6 ppm in each case.

On the other hand, when adjusting the Mg concentration by the above-mentioned method, the nitrate N concentration in the TO formulated culture solution is adjusted by adding an appropriate amount of KNO ₃ , or the KNO ₃ concentration in the first stock solution Done by adjusting the

In this example, a plurality of second stock nutrient solutions were prepared by changing the ratio of Otsuka House No. 2 and MgCl ₂ · 6 H ₂ O, and these and one type of first stock nutrient solution with water 150 times The culture broths of various Mg concentrations were prepared by dilution into. The reason why the first stock solution is one type is to suppress the influence of the component composition contained in the first stock solution on the promoting effect of vegetables by magnesium, but the culture solution is prepared by a method other than the above. You may. For example, methods of preparing one type of first stock nutrient solution and second stock nutrient solution, respectively, and varying the dilution ratio in the case of diluting the first stock nutrient solution and the second stock nutrient solution with the same amount with water, respectively One kind of first stock nutrient solution and second stock nutrient solution are prepared, and the amount of the first stock nutrient solution and the amount of the second stock nutrient solution contained in the culture solution are made different (that is, the first stock nutrient solution) And a method of preparing a culture solution in which the concentration of Mg and the concentration of nitrate N differ by making the dilution ratio of the second stock solution different).

(3) Cultivation period As shown in FIG. 1, the cultivation period is divided into a period from sowing to germination (germination period), a period from germination to transplantation (nursing period), and a period from transplantation to harvest (growth period) The For example, when Komatsuna is cultured by hydroponic culture using a culture solution having a conventional general composition, the germination period is about 3 to 5 days, the nursery period is about 9 to 10 days, and the growth period is about 4 weeks. It takes about six weeks. However, when a plurality of seeds are sown in the nursery apparatus, not all the seeds germinate at the same time.

Therefore, in the following experiment, in order to make the cultivation days uniform, the germination period is from the sowing to the 4th day, and from the 4th day to the 14th day after the sowing is the nursery period. Then, on the 14th day after sowing, the plants grown by the seedling raising apparatus were transplanted from the seedling raising apparatus to the growing apparatus, and thereafter, they were subjected to hydroponic cultivation with the growing apparatus for 3 weeks to 4 weeks. In other words, 3-4 weeks from the 14th day after seeding is the growing period. In Experiment 13, after the growing period, nutrient solution cultivation was performed using a predetermined pre-harvest treatment nutrient solution for three days (pre-harvest period). The pre-harvest treatment solution will be described later. Water was used to equalize the influence of the component composition of the culture solution on the germinated seeds in the germination period, and the TO prescription culture solution, the A prescription culture solution, or the Mg adjusted A prescription culture solution was used in the seedling breeding period and the growth period.

<Experiment 1>
(1) Conditions Using the above-described seedling raising apparatus and growing apparatus, hydroponic cultivation of four types of vegetables (Chimasanchu, Komatsuna, Kos Lettuce, Green Batavia) over the above-mentioned cultivation period (germination period, seedling emergence period and growth period) went.
As a culture solution for the seedling raising period, a TO prescription culture solution with an Mg concentration of 12 ppm, 24, 36, 48, 96 ppm, and 120 ppm was used, and an A prescription culture solution (EC = 1.8) was used as a culture solution for growth period. The nitrate N concentration of TO formulated culture solution is 4.6 ppm, and the nitrate N concentration of A formulated culture solution is 161 ppm.
In addition, it grew on the conditions of 12 hours of light periods-12 hours of dark periods by fluorescent lamp lighting in all the cultivation periods.

(2) Results FIGS. 2A to 2E show the growth of four types of vegetables hydroponically grown using a TO prescription culture solution with an Mg concentration of 12 ppm to 96 ppm during the nursery period, two weeks after sowing It is a photograph showing the situation. As is apparent from FIGS. 2A to 2E, both the above-ground part and the root are better in the case of using the TO formulated culture solution with an Mg concentration of 24-96 ppm than in the case of using the TO formulated culture solution with an Mg concentration of 12 ppm. Growth was good.

3 (a) and 3 (b) show the fresh weight of the above-ground part and roots of Komatsuna harvested after the growing period (that is, Komatsuna harvested 3 weeks after transplanting to the growing apparatus), and used during the nursery period. It shows the relationship with the Mg concentration in the TO formulated culture solution. In the graphs of FIGS. 3A and 3B, the abscissa represents the Mg concentration (ppm), and the ordinate represents the fresh weight (g) three weeks after transplantation of the above-ground parts or roots. Each point on the graph is the average value of 3 individuals.

FIG. 4 shows the relationship between the Mg concentration and the growth promoting effect of roots and above-ground parts obtained from the results of FIGS. 3 (a) and 3 (b). In FIG. 4, the relative acceleration with respect to the growth amount when using the TO formulation culture solution at a Mg concentration of 12 ppm was represented by the number of “+”.

In Experiment 1, the TO prescription culture solution was used in the nursery period (from germination to transplantation), and the A prescription culture solution (Mg concentration = 24 ppm) was used in the growth period. In other words, even though all vegetables are cultured in the same culture solution with the same Mg concentration for 3 weeks after transplantation to the growth apparatus, differences in Mg concentration in the culture solution used during the seedling raising period lead to above-ground parts and roots The growth rate of the plants was different. From this, it was inferred that Mg (magnesium ion) taken in from roots during the nursery period is also involved in the growth and development of the plant after transplantation.

In the above-ground parts, the fresh weight increased with an increase in Mg concentration in the range of 12 to 72 ppm of Mg, and decreased with an increase in Mg concentration in the range of 72 to 120 ppm. As for the root, the fresh weight increased with the increase of the Mg concentration in the range of 12 to 48 ppm of Mg, and decreased with the increase of the Mg concentration in the range of 48 to 120 ppm. That is, it was found that the optimum Mg concentration showing the growth promoting effect was different between the root and the aerial part. This means that the growth promoting action of magnesium ions on the aerial parts does not extend to the roots and vice versa, in other words, magnesium ions act on the meristems of the aerial parts and on the root meristems, respectively. Growth was thought to be promoted.

Therefore, it is possible to adjust the growth rate of vegetables by setting the Mg concentration of the culture solution to an appropriate value according to the time when root growth takes precedence over the growth of aerial parts or vice versa. It was estimated that the time from sowing to harvest could be shortened.

<Experiment 2>
(1) Conditions The sprouting period and the seedling raising period were hydroponically cultivated for Komatsuna using the above-described seedling raising apparatus. 13. In the seedling raising period, adjust the Mg concentration to 12 ppm, 24 ppm and 48 ppm, and the nitrate N concentration to 3.05 ppm (KNO ₃ = 3.8 g / L), 4.6 ppm (KNO ₃ = 5 g / L), 13. 8 ppm (KNO ₃ = 15 g / L), 23 ppm (KNO ₃ = 25 g / L), 41.4 ppm (KNO ₃ = 45 g / L), 78.2 ppm (KNO ₃ = 85 g / L), 184 ppm (KNO ₃ = 200 g) TO formulated culture solution adjusted to / L) was used.
In the germination period and the seedling raising period, cultivation was carried out under the condition of 12 hours of light period by 12 hours of dark period with fluorescent light and 12 hours of dark period.

(2) Results FIG. 5 shows six culture solutions each having an Mg concentration of 48 ppm and a nitrate N concentration of 3.05 ppm, 4.6 ppm, 13.8 ppm, 23 ppm, 41.4 ppm and 78.2 ppm. It is a photograph which shows the appearance of the growth of Komatsuna after 2 weeks after seed sowing when it used. As shown in these photographs, the growth amount of the above-ground parts is large when the nitrate N concentration is 3.05 ppm, 41.4 ppm and 78.2 ppm, and when the nitrate N concentration is 4.6 to 23 ppm It was small. On the other hand, the root elongation amount is large when the nitrate N concentration is 4.6 ppm to 23 ppm ((b) to (d) in FIG. 5), and the nitrate N concentration is 3.05 ppm, 41.4 ppm, 78 At 2 ppm ((a), (e) and (f) in FIG. 5).

6A to 6C show that the Mg concentrations are 12 ppm, 24 ppm, and 48 ppm, and the nitrate N concentration is 4.6 ppm (5 g / L), 13.8 ppm (15 g / L), and 23 ppm (25 g) for each Mg concentration. / L), 41.4 ppm (45 g / L), 78.2 ppm (85 g / L), and 18 ppm (200 g / L), two weeks after seed sowing It is a photograph showing the state of the growth of Komatsuna.

As can be seen from these photographs, focusing on the Mg concentration, overall growth of both above-ground parts and roots is higher at high concentration (48 ppm) than at low concentration (12 ppm, 24 ppm) Tended to increase. On the other hand, focusing on nitrate N concentration, it can be seen that root elongation tends to be greater at lower nitrate concentrations (4.6 ppm, 13.8 ppm) than at higher concentrations (23 ppm to 184 ppm). On the contrary, the growth amount of the above-ground part tended to be smaller at lower nitrate concentrations (4.6 ppm, 13.8 ppm) than at higher concentrations (23 ppm to 184 ppm).

FIG. 7 shows the relationship between nitrate N concentration and the amount of root elongation obtained from FIGS. 5 and 6C. In FIG. 7, relative elongation amount to the root elongation amount at a nitrate N concentration of 184 ppm was represented by the number of “+” with reference to the root elongation amount. From FIG. 5 to FIG. 7, it was found that the growth amount in the above-ground parts and roots differs depending on the nitrate N concentration even if the Mg concentration is the same. In particular, since the amount of growth of Komatsuna was small when the concentration of nitrate N was high from 41.4 ppm to 184 ppm, high concentration of nitrogen (or nitrate ion) was observed in the initial growth of 2 weeks after seed sowing. Was presumed to be unnecessary.

The reason is that (1) When the culture solution contains a large amount of nitrate ions, energy is consumed for nitrate reduction, which is a high priority for plants, and as a result, lack of energy necessary for cell division results in suppression of cell division (2) It is conceivable that there is a mechanism that does not extend the roots when a sufficient amount of nitrogen is present, but the details are unknown.

<Experiment 3>
(1) Conditions The hydroponic cultivation of chimasanchu was carried out using the above-described nursery and growing apparatus for the above-mentioned cultivation period (germination period, nursery period and growth period).
In the experimental section (+ Mg section), a TO formulated culture solution in which the Mg concentration was adjusted to 48 ppm during the nursery period was used. On the other hand, in the comparison section (Cont section), a TO formulated culture solution in which the Mg concentration was adjusted to 12 ppm was used. The nitrate N concentration in the culture solution is 4.6 ppm in both the experimental section and the comparative section.
Further, in each of the experimental section and the comparative section, a Mg adjustment A prescription culture solution (EC = 1.8, nitrate N concentration = 161 ppm) in which the Mg concentration was adjusted to 24 ppm was used for the growth period. In addition, it grew on the conditions of 12 hours of light periods-12 hours of dark periods by fluorescent lamp lighting in all the cultivation periods.

(2) Results FIG. 8 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of chimasanchu. As apparent from FIG. 8, the experimental area grew faster than the comparison area after transplantation, and the experimental area exceeded the harvest line at about 2.5 weeks after transplantation, whereas the comparison area was transplanted in the comparison area. The harvest line was crossed after 3.5 weeks. From the above results, it was found that the period from transplanting to the growth apparatus to harvesting can be shortened by increasing the Mg concentration in the culture solution during the nursery period.

<Experiment 4>
(1) Conditions The hydroponic cultivation of chimasanchu was carried out using the above-described nursery and growing apparatus for the above-mentioned cultivation period (germination period, nursery period and growth period).
In the first experimental group (+ Mg group), a TO prescription culture solution with an Mg concentration of 48 ppm was used during the seedling raising period, and an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm) was used during the growth period.
In the second experiment group (++ Mg group), a Mg preparation A preparation culture solution (EC = 1.8) in which the Mg concentration was 48 ppm in the growth period was used using a TO preparation culture solution having a Mg concentration of 48 ppm in the nursery period. .
In the comparison section (Cont section), a TO prescription culture solution with an Mg concentration of 12 ppm was used during the seedling raising period, and an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm) was used during the growth period.
In addition, in the first experiment area and the comparison area, cultivation is carried out under the condition of 12 hours of light period with fluorescent light illumination 12 hours in the whole experiment period, and in the second experiment area, LED (Raytron in all the cultivation period They were grown under the conditions of 12 hours of light period and 12 hours of dark period by lighting.

(2) Results FIG. 9 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of chimasanchu. As is clear from FIG. 9, the first and second experimental sections had faster growth and development after transplantation than the control section. In addition, in the second experimental group, the second experimental group grew faster than the first experimental group, and in the second experimental group, the harvest line was exceeded about two weeks after transplantation, whereas the first experimental group In the ward, the harvest line was exceeded 2.5 weeks after transplantation. From the above results, it was found that the harvest time of chimasanchu can be advanced by increasing the Mg concentration in the culture solution during the nursery period. In addition, by increasing the Mg concentration in the culture solution both in the seedling growth period and the growth period, it is possible to further accelerate the harvest time of chimasanchu, and in this case, in particular in this case, after transplanting the seedlings to the growth device, It turned out that the cultivation period can be halved.

<Experiment 5>
Using the above-described seedling raising apparatus and growing apparatus, hydroponic cultivation of chimasanchu was carried out during the above-mentioned cultivation period (germination period, seedling raising period and growth period).
In the experimental section (++ Mg section), a TO prescription culture solution (nitrate N concentration = 4.6 ppm) having an Mg concentration of 48 ppm was used during the seedling raising period. In addition, for the growth period, a Mg-adjusted A formulated culture solution (EC = 1.8, nitrate N concentration = 161 ppm) in which the Mg concentration was 48 ppm was used.
In the comparison section (Cont section), a TO formulated culture solution with an Mg concentration of 12 ppm was used. In addition, for the growth period, A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm, nitrate N concentration = 161 ppm) was used.
Further, in all of the experiment period and the comparison period, the cultivation was carried out under the conditions of 12 hours of light period by 12 hours of dark period and 12 hours of dark period by LED (manufactured by Philips Japan Co., Ltd.) lighting throughout the cultivation period.

(2) Results FIG. 10 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of chimasanchu. As apparent from FIG. 10, the experimental area grew faster than the comparison area after growth and development, and the experimental area exceeded the harvest line about two weeks after transplantation, while the comparison area received 3 days after transplantation. The harvest line was exceeded after 5 weeks.

<Experiment 6>
(1) Conditions The hydroponic cultivation of chimasanchu was carried out using the above-described nursery and growing apparatus for the above-mentioned cultivation period (germination period, nursery period and growth period).
In the first experimental section (+ Mg section), a TO prescription culture solution (nitrate N concentration = 4.6 ppm) having an Mg concentration of 48 ppm in the nursery period and an A prescription culture solution (EC = 1.8, Mg) in the growth period Concentration = 24 ppm, Nitrate N concentration = 161 ppm) was used.
In the second experiment group (++ Mg group), the Mg concentration was adjusted to 48 ppm in the growth period (after transplantation) using a TO formulated culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 48 ppm in the nursery period Conditioned A prescription culture medium (EC = 1.8, nitrate N concentration = 161 ppm) was used.
In the comparison section (Cont section), using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 12 ppm in the seedling raising period, an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm, Nitrate N concentration = 161 ppm) was used.
In addition, in the first experiment zone, the second experiment zone, and the comparison zone, cultivation was performed under the conditions of 12 hours of light period by 12 hours of dark period and 12 hours of dark period by fluorescent lamp illumination in all the cultivation periods.

(2) Results FIG. 11 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of chimasanchu. As is clear from FIG. 11, the first and second experimental sections had faster growth and development after transplantation than the control section. On the other hand, in the 1st and 2nd experimental groups, although the growth and development after the 2nd experimental group were a little faster after transplantation, the difference was slight, and both were 2.5 weeks after the transplantation. I crossed the harvest line with my eyes. On the other hand, in the comparison area, the harvest line was crossed around 3.6 weeks after transplantation.

Further, from the results of Experiments 4 to 6, it was found that the amount of growth after implantation into the growth apparatus also differs depending on the lighting fixture. Specifically, although the ++ Mg group in the experiments 4 to 6 used a culture solution having an Mg concentration of 48 ppm during the seedling raising period and the growth period, when a fluorescent lamp was used as a lighting fixture (experiment 6, FIG. 11) The growth amount is larger in the case where LED is used (experiment 4, FIG. 9, experiment 5 and FIG. 10) than in case of), and the case where LED manufactured by Raytron Ltd. is used (experiment 4, FIG. 9) The growth amount was larger in the case of using LED manufactured by Philips Japan (Experiment 5, FIG. 10).

<Experiment 7>
(1) Condition The hydroponic cultivation of Komatsuna was performed over the cultivation period (the germination period, the nursery period, and the growth period) mentioned above using the above-mentioned nursery equipment and growth device.
In the experimental section (++ Mg section), the Mg adjustment A prescription which made 48 ppm of Mg concentration in the growth period (after transplantation) using the TO prescription culture solution with 48 ppm of Mg concentration (nitrate N concentration = 4.6 ppm) A culture solution (EC = 1.8, nitrate N concentration = 161 ppm) was used.
In the comparison section (Cont section), using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 12 ppm in the seedling raising period, an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm, Nitrate N concentration = 161 ppm) was used.
In the experimental section and the comparative section, the cultivation was carried out under the condition of 12 hours of light period by 12 hours of dark period by 12 hours of dark period by fluorescent lamp in all the cultivation period.

(2) Results FIG. 12 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of Komatsuna. As apparent from FIG. 11, in the experimental area, the growth and development after transplantation was faster than in the comparative area, and in the experimental area, the harvest line was exceeded at around 2.7 weeks after transplantation, whereas in the comparative area, the transplantation was transplanted. The harvest line was crossed after 3.5 weeks. From the above results, it was found that the harvest time of Komatsuna can be advanced by using a culture solution having a high Mg concentration both in the nursery period and the growth period.

<Experiment 8>
(1) Conditions Using the above-described apparatus for growing seedlings and the apparatus for growing plants, hydroponics cultivation of Cos Lettuce was performed over the above-mentioned cultivation period (emergence period, period for raising seedlings and growth period).
In the experimental section (++ Mg section), Mg adjustment A prescription with the Mg concentration of 48 ppm in the growth period (after transplantation) using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 48 ppm in the nursery period A culture solution (EC = 1.8, nitrate N concentration = 161 ppm) was used.
In the comparison section (Cont section), using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 12 ppm in the seedling raising period, an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm, Nitrate N concentration = 161 ppm) was used.
In the experimental section and the comparative section, the cultivation was carried out under the condition of 12 hours of light period by 12 hours of dark period by 12 hours of dark period by fluorescent lamp in all the cultivation period.

(2) Results FIG. 13 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of growth of Cos Lettuce. As apparent from FIG. 13, in the experimental area, the growth and development after transplantation was faster than in the comparative area, and in the experimental area, the harvest line was exceeded at around 3.2 weeks after transplantation, while in the comparative area, the transplantation was transplanted. The harvest line was crossed four weeks later. From the above results, it was found that the harvest time of Cos Lettuce can be advanced by increasing the Mg concentration in the culture solution both in the nursery and growth periods.

<Experiment 9>
(1) Conditions Using the above-described seedling raising apparatus and growing apparatus, hydroponic cultivation of Green Batavia was carried out over the above-mentioned cultivation period (germination period, seedling emergence period and growth period).
In the experimental section (++ Mg section), Mg adjustment A prescription with the Mg concentration of 48 ppm in the growth period (after transplantation) using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 48 ppm in the nursery period A culture solution (EC = 1.8, nitrate N concentration = 161 ppm) was used.
In the comparison section (Cont section), using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 12 ppm in the seedling raising period, an A prescription culture solution (EC = 1.8, Mg concentration = 24 ppm, Nitrate N concentration = 161 ppm) was used.
In the experimental section and the comparative section, the cultivation was carried out under the condition of 12 hours of light period by 12 hours of dark period by 12 hours of dark period by fluorescent lamp in all the cultivation period.

(2) Results FIG. 14 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the growth amount of Green Batavia. As apparent from FIG. 14, in the experimental area, the growth and development after transplantation was faster than in the comparison area, and in the experimental area, the harvest line was exceeded at around 3.7 weeks after transplantation, whereas in the comparison area, the transplantation was performed. The harvest line was not exceeded even after 4 weeks. From the above results, it was found that the harvest time of Green Batavia can be advanced by increasing the Mg concentration in the culture solution in both the seedling raising period and the growth period.

From the results of the experiments 1 to 9, although there is a difference, in comparison with the Mg concentration and the nitrate N concentration of the A prescription culture solution which has conventionally been generally used in hydroponic culture of various leafy vegetables, It was confirmed that the growth amount after transplantation into the growth apparatus can be increased by increasing the Mg concentration of the culture solution used for the seedling raising period and lowering the nitrate N concentration. Furthermore, in the case of using the culture solution of high Mg concentration and low nitrate N concentration described above in the nursery period, the Mg concentration of the culture solution used in the growth period is increased, and the nitrate N concentration is A prescription culture. It was confirmed that the amount of growth after transplantation into the growth apparatus can be increased by making the same as or higher than the liquid. Here, experiments were conducted using chima sanchu, komatsuna, cos lettuce, and green batavia, but it was speculated that similar effects could be expected with leafy vegetables other than these.

<Experiment 10>
(1) Conditions The hydroponic cultivation of chimasanchu, komatsuna, cos lettuce, and green batavia was carried out using the above-described seedling raising apparatus and growing apparatus, over the aforementioned cultivation period (germination period, seedling emergence period and growth period).
For all leafy vegetables, a Mg preparation A preparation culture solution with a Mg concentration of 48 ppm in the growth period, using a TO formulation culture solution (nitrate N concentration = 4.6 ppm) with a Mg concentration of 48 ppm in the nursery period. (EC = 1.8, Nitrate N concentration = 161 ppm) was used.

(2) Results FIG. 15 shows that three types of leafy vegetables are harvested three weeks after transplantation into the growth apparatus, and the amount of Mg (mg / 100 g fresh weight) contained in each leafy vegetable is ICP (Inductively) The result measured by (coupled plasma) luminescence analyzer is shown. FIG. 15 shows the amount of Mg of each vegetable listed in the Japanese Food Standard Composition Table (2015), and each leaf harvested in this experiment for the amount of Mg listed in the Japanese Food Standard Composition Table It shows the ratio (increase rate) of the amount of Mg of vegetable. As can be seen from FIG. 15, an increase in the content of Mg was confirmed in all leafy vegetables.

<Experiment 11>
(1) Condition The hydroponic cultivation of Komatsuna was performed over the cultivation period (the germination period, the nursery period, and the growth period) mentioned above using the above-mentioned nursery equipment and growth device.
In this experiment, a Mg-adjusting A prescription culture solution (EC = 1.8, nitric acid N concentration = 161 ppm) in which the Mg concentration was 48 ppm and the Mg concentration was 24 to 120 ppm in the growth period was used. Was used.
In the experiment, the cultivation was carried out under the condition of 12 hours of light period by 12 hours of dark period and 12 hours of dark period by fluorescent light in all the cultivation period.

(2) Results FIG. 16 shows the amount of growth (raw weight (g fw / 3 W)) of Komatsuna harvested through the growing period (that is, Komatsuna harvested 3 weeks after transplanting to the growing apparatus) and the growing period The graph shows the relationship between the concentration of Mg in the culture solution used and each point on the graph is the average value of three individuals, as can be seen from Fig. 16. The concentration of Mg in the culture solution used during the growth period is 24 ppm. In the range of ̃72 ppm, the growth amount increased with the increase of the Mg concentration, but in the range of 72 ppm ̃120 ppm, the growth amount decreased with the increase of the Mg concentration.

As described above, since the concentration of Mg in the culture solution of the conventional formulation is 10 to 40 ppm and the concentration of nitrate N is 60 to 240 ppm, at least in FIG. Growth is considered to be promoted more than conventional prescriptions. That is, it was speculated that the growth of Komatsuna can be advanced earlier than in the past by using a culture solution having an Mg concentration of 48 ppm to 120 ppm in the growing period.

Also, the harvest line (the fresh weight suitable for harvest) of Komatsuna was about 80 g, and in this experiment, the Mg concentration at the 3rd week of the present week exceeded the harvest line in the range of 48 ppm to 120 ppm. From this, it can be seen that if a culture solution having an Mg concentration of 48 ppm to 120 ppm in the growth period is used, the harvest period of 4 weeks can usually be shortened to 3 weeks or shorter.

Experiment 12
(1) Conditions Using the above-described seedling raising apparatus and growing apparatus, hydroponic cultivation of Green Wave, which is a type of leaf lettuce (Asteraceae), was performed over the above-mentioned cultivation period (germination period, seedling emergence period and growth period). .
In the experimental section (++ Mg section), a Mg-adjusted A-prescription culture solution (Mg concentration was adjusted to 72 ppm using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 48 ppm during the nursery period EC = 1.8, Nitrate N concentration = 161 ppm) was used.
In the comparison section (Cont section), using a TO prescription culture solution (nitrate N concentration = 4.6 ppm) with an Mg concentration of 12 ppm in the seedling raising period, an A prescription culture solution with an Mg concentration of 24 ppm in the growth period (EC = 1. 8) was used.
In the experimental section and the comparative section, cultivation was carried out under the conditions of 12 hours of light period by 12 hours of dark period and 12 hours of dark period by LED (manufactured by Raytron Co., Ltd.) lighting in all the cultivation period.

(2) Results FIG. 17 shows the relationship between the elapsed time (weeks) after transplantation into the growth apparatus and the amount of green wave growth. As apparent from FIG. 17, the experimental group had faster growth and development after transplantation than the control group, and the experimental group exceeded the harvest line at about 2.3 weeks after transplantation, while the first experimental group was In the case of 3.7 weeks after transplantation, the harvest line was crossed. From the above results, it was found that the harvest time of green wave can be advanced by increasing the Mg concentration in the culture solution both in the seedling raising period and in the growth period.

<Experiment 13>
(1) Conditions Using the above-described apparatus for growing seedlings and a growing apparatus, hydroponic cultivation of Komatsuna and Green Batavia was carried out over a germination period, a period for raising seedlings, a growing period, and a period before harvesting (3 days).
In this experiment, cultivation of a germination period, a seedling raising period, and a growing period was performed under the same conditions as the experiment group (++ Mg group) of Experiment 7 described above. Then, in the pre-harvest period, using the same growth apparatus as in the growth period, the culture solution and the lighting conditions were changed to carry out hydroponic cultivation.

(2) Conditions for pre-harvest period As the culture solution, nitrate nitrogen and ammonia nitrogen are removed from the above-mentioned A prescription culture solution, calcium chloride is added, and almost no nitrogen is contained, and the calcium content is 30 The nutrient solution (pre-harvest treatment nutrient solution) which is 50, 100, 120, 140 mg / L was used. Here, "substantially free of nitrogen" means that the content of nitrogen is 2.2 g / mL or less. In addition, it is preferable that the quantity of nitrogen contained in pre-harvest treatment nutrient solution is as small as possible. Therefore, when transitioning from the growing period to the pre-harvest period, the container body and the supply path of the growing device were sufficiently washed so that the nitrogen contained in the culture solution used in the growing period did not remain in the growing device.
In addition, visible light with a wavelength of 490 nm or less was continuously illuminated for 24 hours using a blue LED. The photon flux density at this time was 200 μmol / m ² / sec.

(3) Results After performing hydroponic cultivation for a period before harvest using the above-mentioned pre-harvest treatment solution, fresh weight of above-ground parts of Komatsuna and Green Batavia (hereinafter referred to as “experimental section”), ORAC (Oxygen Radical) Absorbance Capacity (active oxygen absorption capacity) value, and the amount of antioxidant component were measured. Also, for comparison, fresh weight, ORAC value, and antioxidant component of above-ground parts of Komatsuna and Green Batavia (hereinafter referred to as “comparative section”) harvested after the growing period (that is, without passing the pre-harvest period) The amount of was measured.
As a result, the fresh weight of the above-ground parts did not differ greatly between the experimental area and the comparison area for either Komatsuna or Green Batavia. On the other hand, the ORAC value and the amount of the antioxidant component were larger in the experimental section than in the comparative section.

In Fig. 18 and Fig. 19, as an example of the experimental section, after being subjected to nutrient solution cultivation for a pre-harvest period using a pre-harvest treatment nutrient solution with a calcium content of 50 mg / L, it is included in harvested Komatsuna and Green Batavia It shows the amount of antioxidant component and the ORAC value. FIGS. 18 and 19 also show the amounts of antioxidant components and ORAC values contained in Komatsuna and Green Batavia in the comparison section.

As is clear from FIG. 18 and FIG. 19, Komatsuna and Green Batavia in the experimental section both contain more antioxidant components than the comparative section, and among the antioxidant components, the amount of glutathione (reduced type) is particularly high. Was increasing.
18 and 19 show an example using a pre-harvest solution with a calcium content of 50 mg / L, but if the calcium content is in the range of 50 to 120 mg / L, almost the same Results were obtained.

FIG. 20 shows the content of glutathione contained in vegetables obtained by a common cultivation method. From the numerical values shown in FIG. 20, it is clear that the content of glutathione contained in Komatsuna and Green Batavia obtained in this experiment is much higher than that of normal vegetables.

Glutathione (reduced form) is known to have the function of reducing and eliminating peroxides and reactive oxygen species, having a detoxifying effect, etc., and is used in medicines, cosmetics and supplements having the following effects. .
(A) Pharmaceutical products:
Improvement of liver function in chronic liver disease Treatment of acute eczema, chronic eczema, dermatitis, inflammation suppressing keratitis such as urticaria, senile cataract, treatment of corneal damage Parkinson's disease treatment (b) suppression of formation of melanin pigment (cosmetic component) Whitening effect)
Vitamin C rejuvenation anti-aging (c) supplements Anti-harvest effect with alcohol that enhances liver detoxification

Since Komatsuna and Green Batavia obtained in Experiment 13 contain a large amount of glutathione, these vegetables are useful as materials for the above-mentioned pharmaceuticals, cosmetics, and supplements, and these vegetables themselves are useful as functional vegetables. Become. Furthermore, from the result of Experiment 10, Komatsuna and Green Batavia obtained in Experiment 13 are expected to contain more Mg than conventional vegetables. From this, Komatsuna and Green Batavia obtained in Experiment 13 can be excellent functional vegetables containing a large amount of both glutathione and Mg.

Fig. 21: After cultivating seedlings (from 4 to 14 days after sowing) and a growing period (4 weeks after transplantation) using a culture solution according to a general conventional formulation, Komatsuna, Komatsuna purple, Chimasanchu, The relationship between the amount of calcium (the amount of Ca) and the antioxidant capacity (ORAC (Oxygen Radical Absorbance Capacity) value) when the pre-harvest treatment is performed for 3 days is shown (see Patent Document 2). The culture solution used in the pre-harvest treatment is prepared by dissolving calcium sulfate in water so that the amount of Ca is 0 to 140 mg / L and the amount of nitrogen is 2.0 mg / L.

As can be seen from FIG. 21, even when hydroponic cultivation is carried out using the culture solution according to the general conventional formulation, the hydroponic cultivation using the pre-harvest treatment hydroponic fluid is performed in the pre-harvest period. As a result, the antioxidant component of vegetables other than Komatsuna (Chimasanchu) also increased. From this, it was estimated that results similar to those of Experiment 13 were obtained even with vegetables other than Komatsuna and Green Batavia.

<Others>
The present invention is not limited to the above-described embodiments, and appropriate modifications are possible.
For example, in the above examples, chimasanchu, komatsuna, kos Lettuce, green batavia, bok choy, leaf lettuce, shung chrysanthemum were used, but the present invention can be applied to leafy vegetables other than these. In addition, not only leafy vegetables, root vegetables such as radish, carrot, turnip, burdock, lotus root, ginger, potato, taro, sweet potato, sweet potato, yam, onion, cucumber, pumpkin, watermelon, melon, tomato, eggplant, pepper, okra The present invention is applicable to all kinds of vegetables such as green beans such as green beans, fava beans, peas, green beans and sweet peppers, and also applicable to, for example, flower buds other than vegetables. In short, considering the principle of plant physiology, the present invention is applicable to all cultivated plants capable of hydroponic culture.

When the amount of Mg contained in leaves of leafy vegetables is large, it often feels bitter when eaten. Therefore, when leafy vegetables are subjected to hydroponic culture and a culture solution having a Mg concentration higher than that of the conventional formulation is used during the growth period, for example, a culture solution having a high Mg concentration is used only in the first half of the growth period. For example (about one week before harvesting), a culture solution with a conventional formulation of Mg concentration may be used. By doing this, it is possible to reduce the amount of Mg contained in the leaves of harvested leafy vegetables.

Claims (8)

1. A method for cultivating cultivated plants using a culture solution containing a fertilizer component necessary for plant growth during the period from sowing to harvesting, which comprises:
   A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. When a seedling grown to a predetermined size is transplanted from the above-mentioned seedling-growing device to a growing device and divided into growing periods which are periods until cultivation is carried out by the growing device,
   A method for cultivating cultivated plants, comprising using a culture solution for raising seedlings wherein the concentration of magnesium ions is in the range of 24 ppm to 120 ppm and the concentration of nitrate nitrogen is in the range of 4 to 50 ppm in the growing period.
2. A method for cultivating cultivated plants using a culture solution containing a fertilizer component necessary for plant growth during the period from sowing to harvesting, which comprises:
   A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. When a seedling grown to a predetermined size is transplanted from the above-mentioned seedling-growing device to a growing device and divided into growing periods which are periods until cultivation is carried out by the growing device,
   A method for cultivating cultivated plants using the culture broth for growth, wherein the concentration of magnesium ions is in the range of 48 ppm to 120 ppm and the concentration of nitrate nitrogen is in the range of 150 ppm to 200 ppm in the growing period.
3. A culture solution used for hydroponic cultivation with a nursery apparatus until the sprouted seedlings grow to a predetermined size, wherein the concentration of magnesium ion is in the range of 24 ppm to 120 ppm, and the concentration of nitrate nitrogen is 4 to Nutrient culture broth in the range of 50 ppm.
4. A culture solution used for hydroponic cultivation of seedlings grown to a predetermined size with a growth apparatus, wherein the concentration of magnesium ion is in the range of 48 ppm to 120 ppm, and the concentration of nitrate nitrogen is in the range of 150 ppm to 200 ppm The culture broth for nutrient solution cultivation.
5. A method for producing high-magnesium leafy vegetables by cultivating leafy vegetables using the nutrient solution cultivation method according to claim 1 or 2.
6. A method for cultivating cultivated plants using a culture solution containing a fertilizer component necessary for plant growth during the period from sowing to harvesting, which comprises:
   A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. Seedlings grown to a predetermined size are transplanted from the seedling raising apparatus to a growing apparatus, and the growing apparatus is a growing period which is a period during which a predetermined time before growing is harvested, the growing apparatus from the harvesting time When divided into the pre-harvest period which is the period of cultivation from the predetermined time before to the harvest time,
   Using a culture solution for raising seedlings wherein the concentration of magnesium ions is in the range of 24 ppm to 120 ppm and the concentration of nitrate nitrogen is in the range of 4 to 50 ppm during the raising period;
   In the pre-harvest period, using a nutrient solution not containing nitrogen but containing calcium, and further irradiating visible light having a wavelength of 490 nm or less, there is provided a method for cultivating cultivated plants, comprising the steps of:
7. A method for cultivating cultivated plants using a culture solution containing a fertilizer component necessary for plant growth during the period from sowing to harvesting, which comprises:
   A germination period, which is a period in which the above-mentioned period is grown from seeding to germination in a seedling-growing device, a period in which the seedling-growing period is grown in the seedling-growing device until the sprouted seedlings are grown to a predetermined size. Seedlings grown to a predetermined size are transplanted from the seedling raising apparatus to a growing apparatus, and the growing apparatus is a growing period which is a period during which a predetermined time before growing is harvested, the growing apparatus from the harvesting time When divided into the pre-harvest period which is the period of cultivation from the predetermined time before to the harvest time,
   In the growing period, a growth medium having a concentration of magnesium ion in the range of 48 ppm to 120 ppm and a concentration of nitrate nitrogen in the range of 150 ppm to 200 ppm is used.
   In the pre-harvest period, using a nutrient solution not containing nitrogen but containing calcium, and further irradiating visible light having a wavelength of 490 nm or less, there is provided a method for cultivating cultivated plants, comprising the steps of:
8. A method for producing high glutathione leafy vegetables by cultivating leafy vegetables using the liquid nutrient cultivation method according to claim 6 or 7.

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