JP2006340689A - Leafy vegetables cultivation method and apparatus - Google Patents

Abstract

The present invention provides a method and apparatus for cultivating leafy vegetables that does not cause a punishment even when cultivated under low sunshine conditions.
In cultivation of leafy vegetables under low sunshine conditions with a length of sunshine, far-red light having a wavelength of at least 700 to 800 nm is reduced from sunlight having a wavelength longer than 700 nm from sunlight under low sunshine conditions, and at night. Irradiate blue light having a wavelength of 400 to 500 nm.
[Selection] Figure 16

Description

  The present invention relates to a method and apparatus for cultivating leafy vegetables. More specifically, the present invention relates to a cultivation method and apparatus suitable for cultivation of leafy vegetables under low sunshine conditions with a chief.

  The cultivation of leafy vegetables is greatly affected by sunshine, and under low sunshine conditions due to seasonal long rain and bad weather conditions, the petiole may grow excessively and may cause a lengthening phenomenon in which the leaf thickness decreases. For this reason, in low sunshine areas such as the Hokuriku region where cloudy weather continues in winter, it is difficult to cultivate leafy vegetables without causing a chief.

  As a solution to such a problem, for example, there is a completely artificial light type cultivation facility. In such a facility, since artificial light can be maintained at an intensity that does not cause poor growth, it is possible to cultivate leafy vegetables with good commercial value without causing a lengthening.

In addition, it has been proposed to suppress the length by adjusting the illumination light (Patent Document 1). This cultivation method is a stage where only red light having a peak wavelength of 600 to 700 nm is grown with a light semiconductor as a light source for leafy vegetables such as lettuce, saladana, and spinach that are currently being cultivated in a fully artificial light type or solar combined type cultivation facility. By adjusting the amount of light and irradiating the light, it is intended to suppress the puppet.
JP 09-37648 A

  However, in a complete artificial light type cultivation apparatus, it takes a great amount of power cost to maintain artificial light at a strength that does not cause poor growth, so it is not profitable to cultivate leafy vegetables with good commercial value.

  Moreover, in the cultivation technique of the cited document 1, red light having a wavelength of 600 to 700 nm, which is said to suppress the length, is naturally included in sunlight under low sunshine conditions, but the length is generated.

  Therefore, the present invention provides a method and apparatus for cultivating leafy vegetables that can lead to height suppression and increase in dry weight of edible parts even under low sunshine conditions, and a completely artificial light type that can be realized even at low power costs It aims at providing the cultivation method and apparatus of leaf vegetables by a cultivation facility.

  The present inventors have found that the illuminating phenomenon under low sunshine conditions is insufficient for the irradiation intensity of red light having a wavelength of 600 to 700 nm, which is said to suppress the estrus, or in addition to the red light component, I thought that the priest might occur because there is a light component that promotes the priest rather than suppression.

  As a result of extensive research conducted by the present inventor based on such knowledge, it is possible to suppress the length even under low sunshine conditions by reducing far-red light having a wavelength of 700 to 800 nm from light irradiated in the daytime. I found out. Furthermore, it was found that it is possible to simultaneously achieve length control and increase in edible part dry weight by irradiating blue light having a wavelength of 400 to 500 nm at night.

  The method for cultivating leafy vegetables according to claim 1 is to reduce the length of light by reducing far-red light having a wavelength of at least 700 to 800 nm out of light having a wavelength longer than 700 nm from sunlight under low sunshine conditions. Irradiation with blue light having a wavelength of 400 to 500 nm causes an increase in the dry weight of the edible portion and an increase in the thickness of the leaf.

  As a method for reducing far red light, as described in claim 3, a far red light shielding material may be used, and specifically, a commercially available far red light cut film may be used. It is considered that far-red light has a role as a signal for encouraging the chief of leafy vegetables during cultivation. Therefore, it is only necessary to shield far-red light from the sunlight component irradiated in the daytime to the extent that the chief is not encouraged, and it is only necessary to shield about 50%, preferably 50% or more, more preferably 70% or more, It is preferably 86% or more, and most preferably complete shielding.

  The method for cultivating leafy vegetables according to claim 2 is a cultivation method under completely artificial light. Under fully artificial light, as a method of reducing far-red light from light irradiated in the time corresponding to daytime, when using a white illuminant as a light source, between the illuminant and leaf vegetables being cultivated It is sufficient to use a far-red light shielding material, but a light source that does not substantially include at least a far-red light component having a wavelength of 700 to 800 nm out of light having a wavelength longer than 700 nm may be used. Blue (400 to 500 nm), green (500 to 600 nm), and red (600 to 700 nm) light emitters may be used in combination.

  In the case of reducing the far red light component in the white light emitter by using the far red light shielding material between the white light emitter and the leafy vegetables being cultivated, it is concrete as the far red light shielding material as described above. In the case of using a commercially available far-red light cut film, it is sufficient to shield far-red light from light components irradiated at the time corresponding to the daytime at least to the extent that the chief is not encouraged. However, it is preferably 50% or more, more preferably 70% or more, still more preferably 86% or more, and most preferably complete shielding.

  As a light source, blue (400 to 500 nm), green (500 to 600 nm), and red (600 to 700 nm) light emitters are used in combination. When light is not substantially contained, it is ideal that far-red light having a wavelength of 700 to 800 nm is not included among light having a wavelength longer than 700 nm. However, in general, since the light emitter has a wavelength distribution, it may contain some far-red light components. Therefore, when the wavelength distribution of the red illuminant extends to a wavelength range longer than 700 nm, the PPFD in the light component having a wavelength longer than 700 nm should be at least strong enough not to promote the length, and 600 nm to 700 nm. The PPFD of far-red light of 700 to 800 nm may be about 50% with respect to the PPFD of the red light component, but is preferably 50% or less, more preferably 30% or less, still more preferably 14% or less, most preferably Preferably it is 0%.

  In addition, in an artificial light source, when the photosynthesis effective photon flux density (hereinafter abbreviated as PPFD) in a wavelength component longer than 700 nm cannot be increased to such an extent that the length is not promoted, these light emitters and cultivation A far-red light shielding material may be used between the leafy vegetables in the middle.

  The light emitter used in the present invention is, for example, a fluorescent lamp, an LED, or an organic EL, but is not limited thereto.

  The time corresponding to the daytime under fully artificial light varies depending on the crop type, but generally it may be about 10 to 14 hours, and the other time may be the time corresponding to the night.

Furthermore, as described in claim 4, the blue light irradiation time of a wavelength of 400 to 500 nm in the night or a time zone corresponding to the night may be at least 4 hours. Moreover, the PPFD should just be at least 80 micromol ^- 2s ^{- 1} or more. If the PPFD is increased and the blue light is irradiated for a longer period of time, the effect of the present invention appears more conspicuously, but it is not desirable to set the PPFD large in view of power cost.

The said blue light irradiation should just irradiate to the leaf vegetables under cultivation the blue light of the grade which acts on the increase in the dry weight of an edible part, the increase in the thickness of a leaf, and can promote the effect | action. According to the experiments by the present inventors, it was confirmed that it is sufficient that the amount of light energy for irradiation is secured to about 1.15 molm ⁻² or more overnight. Therefore, even if the irradiation time is short, if the energy of 1.15 molm ⁻² or more can be secured overnight, the effect of blue light irradiation at night can be obtained.

However, if the PPFD is 60 μmolm ⁻² s ⁻¹ or more and less than 80 μmolm ⁻² s ⁻¹ , the effects of the present invention may not be significantly exhibited depending on the plant, and the PPFD is 40 μmolm ⁻² s ⁻¹ or more and 60 μmolm ^{−. If} it is less than ² s ^-1 , depending on the plant, the leaves will spread in an attempt to efficiently absorb the photons being irradiated and the surface area of the leaves will increase, making it difficult to grow leafy vegetables with thick leaves. There is a possibility.

Therefore, PPFD is preferably at least 80 μmol ⁻² s ⁻¹ , and the amount of energy irradiated to leaf vegetables is preferably about 1.15 mol ⁻² or more overnight.

  In addition, as described in claim 5, the effect of blue light irradiation is likely to appear when it is performed at night near dawn. That is, by irradiating blue light at night close to dawn, the reward for energy input for blue light irradiation is increased.

  The leafy vegetables in the present invention are not particularly limited, but specific examples include cruciferous, red, and chrysanthemum leafy vegetables, with cruciferous leafy vegetables being particularly preferred.

  According to the present invention, by introducing a far-red light shielding material and a blue light irradiation device for reducing far-red light, it is possible to cultivate leafy vegetables that do not cause a long-term cultivation under low sunshine conditions. In addition, when the present invention is applied to completely artificial light cultivation, leaf vegetables can be cultivated without causing a height even if the daytime illumination is reduced to PPFD where the height is normally generated, thereby reducing the power cost. It becomes feasible.

In addition, the cultivation method of the present invention obtains leafy vegetables having an increased edible portion dry weight and leaf thickness without causing a height increase even when the PPFD is reduced to a low-light condition where the height is generated. It is possible. In fully artificial light cultivation facilities, PPFD is set to about 300 μmol ⁻² s ⁻¹ in order to prevent the pupae from being raised. However, according to the cultivation method of the present invention, PPFD that produces a puppet is also acceptable. Since it is possible to obtain leafy vegetables having an increased dry portion weight and leaf thickness, the lighting cost can be reduced as compared with the conventional case. In addition, the illuminance condition for generating a chief varies depending on the crop type and the temperature condition. For example, if the cultivation environment is not high, there is a crop type that does not cause a chief even with a PPFD of about 150 μmol ⁻² s ⁻¹ . Even in such a case, if the cultivation method of the present invention is applied, leaf vegetables having an increased edible portion dry matter weight and leaf thickness can be obtained without increasing the length even when PPFD is subjected to low illumination conditions. Is possible. It is also possible to obtain leafy vegetables with higher commercial value by setting the PPFD in the daytime to a PPFD that does not cause a chief and performing blue light supplement at night.

  Hereinafter, the configuration of the present invention will be described in detail based on the embodiments shown in the drawings.

  FIG. 17 shows an embodiment of a solar-powered cultivation apparatus that implements the leaf vegetable cultivation method of the present invention shown in FIG. 16. This solar combined cultivation apparatus 1 takes in natural light during the daytime and supplements light with artificial light at night. Under low daylight conditions in the daytime, light having a wavelength longer than 700 nm from sunlight. Among them, far red light having a wavelength of 700 to 800 nm is shielded to suppress the length, and blue light is irradiated at night to increase the dry weight of the edible portion and the leaf thickness. The solar combined use cultivation device 1 is a far red light for shielding a far red light having a wavelength of at least 700 to 800 nm out of light having a wavelength longer than a wavelength of 700 nm from the roof 2 capable of transmitting sunlight. The shielding material 3, the far-red light shielding material supply device 4 for sending out and winding the far-red light shielding material to cover the leafy vegetables, the blue light source 5 for irradiating blue light with a wavelength of 400 to 500 nm, It consists of a light control device 8 for adjusting the light source. In this embodiment, the leafy vegetables 6 are planted on the cultivation stand 7 in the cultivation apparatus and hydroponically cultivated.

  The roof 2 may be formed of a material that can transmit sunlight, and a material that can transmit at least a light component of 400 nm or more may be used. For example, vinyl chloride or the like normally used in a greenhouse may be used, but is not limited thereto, and any material that satisfies the above conditions may be used. Alternatively, it may be completely openable and closable so that natural light can be directly collected.

  The far-red light shielding material 3 is only required to shield far-red light having a wavelength of at least 700 to 800 nm out of light longer than 700 nm from sunlight in the daytime to such an extent that the length is not encouraged, and about 50%. However, it is preferably 50% or more, more preferably 70% or more, still more preferably 86% or more, and most preferably complete shielding. A far-red light shielding material that satisfies the above conditions is commercially available. For example, a heat ray shielding film (YXE-5) manufactured by Mitsui Platec Co., Ltd. may be used. As shown in FIG. 16, the far-red light shielding material is provided on the inner side of the roof 2. However, the far-red light shielding material is disposed at a position where the leaf vegetables 6 can be irradiated with the light shielding the far-red light component from sunlight. The position is not limited to the above.

  The far-red light shielding material supply device 4 is a device for sending out and winding up the far-red light shielding material to cover leaf vegetables. This device is equipped with a roller, the far-red light shielding material is wound around the roller, the far-red light shielding material is sent out by rotating the roller in one direction, and the far-red light light is rotated in the reverse direction. What is necessary is just to wind up a shielding material. The roller may be driven manually or may be driven by a motor or the like.

  In this way, by sending out the far-red light shielding material and making it possible to wind it up, for example, when the irradiation intensity of sunlight is strong and it does not become under low sunshine conditions, it is cultivated without shielding the far-red light Since the leafy vegetables 6 in the middle do not wake up, it is possible to prevent deterioration of the far-red light shielding material by winding up the far-red light shielding material and not exposing it to sunlight.

  In FIG. 16, the far-red light shielding material is provided only on the inner side of the roof 2. However, when this alone cannot sufficiently shield the far-red light, a far-red light shielding material is further used on the side wall. Also good.

  The blue light source 5 is a light source for irradiating blue light having a wavelength of 400 to 500 nm. The light amount of the light source is preferably adjusted by a dimmer, but may be adjusted by the number of lamps and the distance between the leaf vegetables 6 and the white fluorescent lamp.

The leaf vegetables 6 that are being cultivated are irradiated with at least 4 hours or more of blue light having a PPFD of 80 μmolm ⁻² s ⁻¹ or more overnight by the blue light source 5.

  In addition, the effect of the present invention is remarkably exhibited with respect to the energy input for the blue light irradiation by setting the irradiation time zone of the blue light at night near the dawn.

  As described above, the leafy vegetables 6 cultivated by hydroponics using the cultivation facility are cultivated without causing the chief. In addition, the cultivation method is not restricted to hydroponics, for example, you may grow by soil culture.

  The method for cultivating leafy vegetables of the present invention can be applied to leafy vegetables of the Brassicaceae, Rubiaceae and Chrysanthemum departments, and in particular, application to leafy vegetables of the Brassicaceae is effective.

  FIG. 17 shows an embodiment of a fully artificial light cultivation apparatus 9 for leafy vegetables of the present invention. The difference between this complete artificial light type cultivation apparatus 9 and the combined sunlight type cultivation apparatus 1 in FIG. 16 is that the light irradiated in the daytime is not sunlight but artificial light, and blocks light from the outside. It is a point provided with the roof 11, and all the apparatus configurations other than that are the same.

  The roof 11 may be made of a material that can block sunlight and light incident from the outside.

  The light source 10 may be a white fluorescent lamp or a combination of a blue fluorescent lamp, a green fluorescent lamp, and a red fluorescent lamp.

  Since the white fluorescent lamp contains a far red light component, it is necessary to shield the far red light component. What is necessary is just to perform the shielding method similarly to said sunlight combined type cultivation apparatus.

  Note that the amount of light of the white fluorescent lamp may be such that leafy vegetables are prone. Thereby, it is possible to realize a low power cost. The light amount of the lamp is preferably adjusted by a dimmer, but may be adjusted by the number of lamps and the distance between the leaf vegetables 6 and the white fluorescent lamp.

  In addition, as the light source 10, you may use the light source which does not contain the far red light of wavelength 700-800nm at least among the light longer than wavelength 700nm. Specifically, blue (output wavelength range 400 to 500 nm), green (output wavelength range 500 to 600 nm), and red fluorescent lamp (output wavelength range 600 to 700 nm) are used. It may be adjustable. The amount of light can be adjusted by adjusting the distance between the leaf vegetable 6 and the light source 10 and also by the number of blue, green and red fluorescent lamps.

  Here, “substantially free” means that the PPFD of the light component having a wavelength longer than 700 nm is at least strong enough not to promote the length of the light, and is compared to the PPFD of the red light component of 600 nm to 700 nm. The PPFD of far-red light of 700 to 800 nm may be about 50%, but is preferably 50% or less, more preferably 30% or less, still more preferably 14% or less, and most preferably 0%.

  Further, the intensity ratio of each of the blue, green, and red fluorescent lamps may be an intensity ratio that can achieve a composition close to that of sunlight, but may be any composition ratio that can be grown while suppressing the length.

  In addition, the arrangement position of the light source 10 is not limited to the position in FIG. 17, and it is also arranged on the side surface of the cultivation apparatus 9 so that the leaf vegetables 6 can be irradiated with light more efficiently. Good. In this case, when using a white fluorescent lamp, a far red light shielding material may be used between the leaf vegetable 6 and the white fluorescent lamp so as to reduce the far red light component from the irradiated light component. What is necessary is just to arrange | position a red light shielding material to the side wall of a cultivation apparatus.

  The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention. For example, the roof 11 of the fully artificial light cultivation device in FIG. 17 is made to be capable of transmitting sunlight, and a white fluorescent lamp is used as the light source 10 so that sunlight and artificial light are used in the daytime. Good. In addition, the cultivation apparatus of the present invention is used during the low-light period of the year, and the far-red light shielding material is wound up and compensated for when it is not low-light period, i.e., when it does not cause the illusion. You may make it grow as usual, without performing light.

  The cruciferous leafy vegetables, Chingensai, Bekana, and Komatsuna are nurtured by the following methods. The effect was tested.

(Experimental device)
Four artificial light type growth chambers are prepared, and the light source of the dimming lighting device in which the dimming lighting device is installed in each air conditioning room is a blue, green, red and far-infrared monochromatic fluorescent lamp (FLR1250T6 type, Nippon Electric) ), And the output of the monochromatic fluorescent lamp was adjusted by the power unit for each experimental process. Spectral photon distribution of the fluorescent lamp is measured with a spectroradiometer (MSR7000, Opto-Research), PPFD is measured with a photon sensor (LI-190B, Li-Cor Inc.) and obtained as an average value of 9 points on the cultivation panel. It was.

(Cultivation method of plant material)
Seeds of the above-mentioned test plants were sown on a urethane cube to germinate, and the PPFD of a white fluorescent lamp (FLR110HW / A / 100; Mitsubishi Electric) was set to 110 μmol ⁻² s ⁻¹ to irradiate them. After growing for 7 days at 23 to 25 ° C., the seedlings with the first two leaves developed to the same size were selected and placed in the artificial light type growth chamber shown below. × 600 × 200 mm) The seedlings were transferred to the cultivation panel above and cultivated for 21 days. Hydroponic cultivation liquid was produced using Otsuka House Fertilizer A prescription (Otsuka Chemical Co., Ltd.) and cultivated by adjusting the electrical conductivity to 1.2 dSm ⁻¹ and the pH to 5.0 to 6.5. Moreover, the temperature in the chamber during the cultivation period was kept constant at 25 ° C.

(Light processing)
The PPFD set in this experiment is the sum of PPFD of blue light (B), green light (G), and red light (R). The composition of the visible light component in the basic condition (Control) is 30% for B and G for G 40% and R was 30%. The ratio of red light to far red light (R / FR) was set to 1.0. In far-red light cut (-FR), only the far-red light component is reduced by 86% from the basic condition, and in blue light plus (+ B), only the blue light component is increased by 67% from the basic condition. Decreased.

(Comparative Example 1) Daytime light quality conversion
Growth when PPFD in the growth chamber is set to two levels of 100 and 150 μmolm ⁻² s ⁻¹ which are close to those in cloudy weather, and light quality conversion is performed in the daytime (6: 00 to 18:00, 12 hrs) The effects on the Table 1 shows the light processing conditions. The numbers in the table indicate PPFD (unit: μmolm ⁻² s ⁻¹ ), B indicates blue light, G indicates green light, R indicates red light, FR indicates far red light, and maintains the value of PPFD. Control zone (basic condition) of spectral composition close to natural light, + B zone (blue light plus) with increased blue light, -FR zone (far-red light cut) with reduced far red light, farther with increased blue light Eight treatment sections of + B-FR section with reduced red light were set.

(Comparative example 2) Light quality conversion in night supplementary light The PPFD in the growth chamber was set to three stages of 35, 100, and 150 μmolm ⁻² s ⁻¹ , and the presence or absence of the influence of light quality conversion in the night supplemented light was examined. Table 2 shows the light processing conditions. The daytime was set to a time zone of 6:00 to 16:00 (10 hrs), and all were set to light quality close to natural light. Night supplementary lighting was performed at a time of 2:00 to 6:00 (4 hrs), and the PPFD at that time was set to the same level as in the daytime. Light quality in nighttime supplementary light is controlled by the spectral composition of near-natural spectrum, increased blue light + B (blue light plus), reduced far-red light -FR (far-red light cut), increased blue light Twelve treatment zones of + B-FR zone with reduced far red light were set.

(Example 1) Blue supplementary light at night and far-red light cut during the daytime The combined effect of nighttime blue supplementary light and daytime far-red light cut was examined. Table 3 shows the light processing conditions. The PPFD in the daytime (6: 00 to 16:00, 10 hrs) is set to 150 μmol ⁻² s ⁻¹ , and the PPFD in the blue light supplement at night (2: 00 to 6:00, 4 hrs) is 80 μmol ⁻² s ^−1. Set to. Control zone with spectrum composition close to natural light, + nB zone (during daytime blue supplementation is performed in the same way as control in the daytime), -FR + nB zone (blue supplementation with nighttime composition with reduced far red light in the daytime), Four treatment zones of + B-FR were set.

(A) Daytime light quality conversion to Chingensai and Bekana: Comparative Example 1
The daytime was 12 hours from 6:00 to 18:00, and the night time was 12 hours from 18:00 to 6:00. For daytime light quality conversion, PPFD is set to 100 or 150 μmol ⁻² s ^−1, and light treatment performed with light quality having a spectral composition close to natural light is used as a control, and blue light is increased or far red light is Light treatment that was reduced or used in combination was performed for 21 days.

(B) Light quality conversion in night supplementation to Chingensai, Bekana, Komatsuna: Comparative Example 2
The daytime was 10 hours from 6:00 to 16:00, and the night time was 14 hours from 16:00 to 6:00. PPFD was set to 35, 100, and 150 μmol ⁻² s ^−1, and light treatment was performed with light quality having a spectral composition close to natural light in the daytime. Night supplementary light was set at 4 hours from 2:00 to 6:00, and the PPFD at that time was set to the same level as in the daytime. A light treatment carried out with light quality having a spectral composition close to that of natural light was used as a control group, and a light treatment carried out for 21 days was performed by increasing blue light, reducing far-red light, or using them in combination.

(C) Nighttime blue supplementary light and daytime far-red light cut to Chingensai, Bekana, and Komatsuna: Example 1
The daytime was 10 hours (6: 00 to 16:00) and the night was 14 hours (16: 00 to 6:00). Daytime PPFD is the 150μmolm ^-2 s ^-1, PPFD at night blue light supplement was set to 80μmolm ^-2 s ^-1. Night supplementary light was set to 4 hours (2: 0 to 6:00), and the PPFD at that time was set to the same level as in the daytime. The control group is one that does not perform blue light supplementation at night with a spectral composition close to natural light in the daytime, and the one that performs blue light supplementation at night with a spectral composition close to natural light in the daytime. The treatment was carried out for 21 days with light treatment by shielding red light and performing blue light supplementation at night, or by light treatment by cutting far red light during the daytime and performing blue light supplementation at night.

(Measurement and analysis of plant growth)
After completion of the light treatment, the test plants were harvested in 8 or 10 strains in each section, and after measuring the plant height, they were divided into leaves (leaf blades), stems (stems + petiole) and roots. The total leaf area was measured using an image processing apparatus. In addition, specific leaf area (leaf area / leaf dry weight) was calculated in order to compare the difference in leaf morphology. For the largest leaf, leaf length, leaf width and petiole length were measured. The separated material was dried at 60 ° C. for 7 days using a ventilating dryer, and the dry weight of leaves (leaf blades), stems (stems + petiole), and roots were determined. Growth parameters were tested for significant differences between the mean values by Tukey's multiple comparison (p <0.05).

(Analysis of components contained in test plants)
On the 22nd day from the start of light treatment, 4 strains were harvested for each ward, and each edible portion (leaves and stems) was shredded, weighed 2.0 g each with fresh weight, and immediately ascorbic acid (vitamin C ) And β-carotene (vitamin A) quantified in an extraction solvent (20 ml).

(Quantification of β-carotene)
2.0 g of the shredded sample was immersed in 20 ml of an acetone solution containing 2% pyrogallol and crushed in ice using a Polytron homogenizer (KINEMATICA). The solution was subjected to suction filtration with glass filter paper (GF / A Whatman), and then acetone was added thereto to make up to 100 ml and quantitatively analyzed by HPLC.
Inertsil ODS-3 (5 μm, 4.6 × 150 mm; GL Sciences) was used for the HPLC column, and methanol and chloroform were mixed 4: 1 (v / v) in the mobile phase and thoroughly degassed. It was used. The flow rate of the pump (L-7100, Hitachi, Ltd.) is 1.5 ml min- ¹ , the column temperature is 30 ° C., a peak is detected at a wavelength of 450 nm using a UV detector (SPD-6AV Shimadzu Corporation), and HPLC analysis software ( D-7000 type advanced HPLC system manager, Hitachi, Ltd.) and chromatogram analysis, and quantified by comparison with a calibration curve using a standard. Here, the calibration curve is an approximate function obtained by chromatograming a solution obtained by dissolving β-carotene in acetone at various concentrations and plotting the chromatogram intensity against the β-carotene concentration.

(Quantitative determination of ascorbic acid)
2.0 g of the chopped sample was immersed in 20 ml of an aqueous solution containing 5% metaphosphoric acid and crushed in ice using a Polytron homogenizer (KINEMATICA). After 1.5 ml of the solution was dispensed into a microtube and centrifuged at 10,000 rpm for 1 minute to precipitate the residue, a test paper (reflect quant ascorbic acid test: Cat. No. 16981- was added to the supernatant. 1M, Kanto Kagaku) and quantified using a small reflection photometer (RQflex plus, Merck KGaA).

(Experimental result)
a. Effects of daytime light conversion to Chingensai and Bekana (Comparative Example 1)
The results of examining the effects of daytime light quality conversion on plant height, petiole length, leaf width and leaf length are shown in FIG. In Chingensai, no significant change was observed between the Control group and the + B group under both the PPFD150 and PPFD100 conditions, but the plant height, petiole length and leaf length were significantly decreased in the -FR group and the + B-FR group. (FIGS. 1A and 1B). PPFD150 and PPFD100 mean PPFD150 μmolm ⁻² s ⁻¹ and PPFD100 μmolm ⁻² s ⁻¹ , respectively, and the units are omitted hereinafter. The leaf width tended to be smaller than the other measurement items. The test group that decreased most was the + B-FR group. Compared with the Control group, the plant height was 76%, the petiole length was 75%, the leaf width was 83%, and the leaf length was 78% at PPFD150. In PPFD100, the plant height was 73%, the petiole length was 63%, the leaf width was 81%, and the leaf length was 78%. Also in Bekana, no change was observed in the + B section under both the PPFD150 and PPFD100 conditions (FIGS. 1C and 1D). In the case of PPFD150, only the petiole length decreased in the -FR group, and the plant height, petiole length and leaf width decreased in the + B-FR group (FIG. 1C). In the case of PPFD100, the plant height and petiole length decreased in the -FR group, and the plant length, petiole length, leaf width and leaf length all decreased in the + B-FR group (FIG. 1D). As in the case of Chingensai, + B-FR treatment has the largest change in Bekana. In PPFD150, the plant height is 85%, the petiole length is 59%, and the leaf width is 90% compared to the Control group. In PPFD100, The plant height was 77%, the petiole length was 64%, the leaf width was 78%, and the leaf length was 82%.
Next, FIG. 2 shows the results of examining the effect of daytime light conversion on the dry weight of leaves, stems and roots. In both Chingensai and Bekana, the leaf dry matter weight was not significantly different from the Control group in all treatments regardless of PPFD strength. In addition, regarding the dry weight of roots and stems, no significant difference was observed in the + B group from the Control group. However, in Chingensai, in the case of PPFD150, the dry weight of the stem decreased in the -FR section, and the dry weight of the stem and root decreased in the + B-FR section (FIG. 2A). In the case of PPDF100, the dry weight of stems and roots decreased in both the -FR group and the + B-FR group (FIG. 2B). In Bekana, there was no change in the dry weight of the roots, but the dry weight of the stem decreased in the + B-FR section of PPFD150 and the -FR and + B-FR sections of PPFD100 (FIGS. 2C and 2D). The change in the dry weight of the stem by + B-FR treatment was large in both Chingensai and Bekana. Compared with the Control group, it decreased to 50% in PPFD150 and 39% in PPFD100 compared with Control, and 57% in Bekana with PPFD150. In the case of PPFD100, it decreased to 47%. Further, FIG. 3 shows the effect of daytime light quality conversion on the specific leaf area (leaf thickness). In Chingensai, a significant decrease in the specific leaf area was observed only in the + B-FR group in the case of PPFD150, but decreased in both the -FR group and the + B-FR group in PPFD100. On the other hand, in bekana, no decrease was observed in all cases of PPFD100, but in the case of PPFD150, it decreased in the -FR and + B-FR sections.
As a parameter to determine the length-controlling effect, we selected the petiole length and leaf thickness (specific leaf area) and compared it with Chingensai and Bekana. It was found that petiole elongation was suppressed (FIG. 12A) and leaf thickness increased (FIG. 12B). This effect was not recognized even when the treatment for increasing only blue light was performed, but when two light treatments were performed simultaneously, the effect of suppressing the expansion of the petiole was stronger than the single treatment of far red light cut. Became clear. Next, comparing the effects of the edible part on dry matter production, it was revealed that the dry weight of the edible part in both crops was lower than that in the Control group in the + B-FR section (FIG. 13). ). It was also found that the dry matter weight decreased mainly in the petiole / stem part, and the leaf blade part did not change much. Assuming cultivation under low sunshine conditions, reducing dry matter production in the edible part should be avoided. It is considered good. Also, from these results, it became clear that if PPFD is at least 100, an effect of suppressing the length is recognized.

b. Effect of light quality conversion on nighttime supplementation to Chingensai, Bekana and Komatsuna (Comparative Example 2)
FIG. 4 shows the results of examining the effects of nighttime supplementary light quality conversion on plant height, petiole length, leaf width, and leaf length. In the case of PPFD150, plant height, leaf width and leaf length decreased in the + B section of Chingensai, plant height, petiole length and leaf length decreased in the -FR section, and plant height and leaf length decreased in the + B-FR section (Fig. 4A). On the other hand, no significant change was observed between Bekana and Komatsuna (FIGS. 4B and 4C). In the case of PPFD100, changes were observed only in the + B-FR section, the plant height, petiole length, and leaf length decreased in Chingensai (Fig. 4D), plant length and leaf length decreased in Bekana (Fig. 4E), and plant height in Komatsuna. Decreased (FIG. 4F). In the case of PPFD35, the leaf length decreased in the + B section in chingensai, and all the plant height, petiole length, leaf width and leaf length decreased in the -FR and + B-FR sections (FIG. 4G). In Bekana and Komatsuna, changes were observed only in the + B-FR section, and plant height, petiole length, leaf width, and leaf length all decreased (FIGS. 4H and 4I). Next, FIG. 5 shows the results of examining the effect of nighttime supplementary light quality conversion on the dry weight of leaves, stems and roots. Under the conditions of PPFD150 and PPFD100, no change was observed in the dry weight of leaves, stems, and roots for both Chingensai, Bekana, and Komatsuna (FIGS. 5A to 5F). In the case of PPFD35, the dry weight of stems and roots was decreased in the -FR section in Chingensai, and the dry weight of the stem was decreased in the + B-FR section (FIG. 5G). In Bekana, the dry weight of roots decreased in the + B-FR section (FIG. 5I). Further, FIG. 6 shows the effect of nighttime supplementary light quality conversion and PPFD level on specific leaf area. In Chingensai, no change was observed under the conditions of PPFD150 and PPFD100, but in the case of PPFD35, the specific leaf area decreased in the -FR and + B-FR sections. Moreover, the change was recognized only in the case of PPFD150 in the beaker, and the specific leaf area decreased in the -FR group and the + B-FR group. On the other hand, in Komatsuna, there was no change in specific leaf area according to the light quality conversion of PPFD or night supplementary light.
It was examined whether the light quality conversion of nighttime supplementary light and PPFD level affect the contents of β-carotene and ascorbic acid (vitamin C), which are the main nutritional components of leafy vegetables tested, and in comparison with the Control group No change was observed in β-carotene content in Chingensai and Komatsuna regardless of the quality of light supplemented at night (FIGS. 7A and 7C). In bekana, an increase in β-carotene content was observed only in the −FR section in the case of PPFD150 (FIG. 7B). On the other hand, ascorbic acid content did not change in Chingensai and Bekana regardless of the light quality of nighttime supplementation (FIGS. 8A and 8B), but Komatsuna decreased in the + B and + B-FR zones for PPFD150. In the case of PPFD100, it decreased in the + B-FR section (FIG. 8C).
In Chingensai, the plant height was shorter in the + B, -FR, and + B-FR plots than in the Control plot in the nighttime light supplement of PPFD150. The cause of this was the decrease in leaf length in the + B plot, and in the -FR plot. Is due to a decrease in petiole length (FIG. 4A). In PPFD100, the single effect of blue light plus and far-red light cut was not shown (FIG. 4D), but in the case of PPFD35, leaf length decreased in + B section, and leaf length and petiole length decreased in -FR section. (FIG. 4G). Basically, it is considered that the effect of blue light plus is likely to appear at high PPFD, but the effect of blue light plus is not observed in intermediate PPFD 100, and the reason why it is recognized in PPFD 35 is unknown. In Bekana and Komatsuna, the effect of nighttime supplementary light quality conversion on the plant height was observed only in the + B-FR section, and the elongation suppression effect appeared only under low PPFD conditions (FIGS. 4H and 4I). As for dry matter weight, no effect was observed in Bekana, and it decreased only in the + B-FR section of PPFD35 in Komatsuna (FIG. 5). In this way, in Bekana and Komatsuna, there was no single effect of blue light plus and far-red light shielding on extension growth and dry weight, so Bekana and Komatsuna had more influence on light quality during nighttime supplementation than Chingensai. It is thought that it is hard to receive. It was examined whether the light quality of nighttime light supplementation and PPFD level affect the contents of β-carotene and ascorbic acid. In Chingensai and Komatsuna, there was no change in β-carotene content regardless of the light quality of nighttime light supplementation. An increase in β-carotene content was observed only in the -FR section (PPFD150). However, when the β-carotene content was compared at the PPFD level, the stronger the PPFD, the higher the β-carotene content. Therefore, the β-carotene content of Chingensai, Bekana, and Komatsuna was not affected by the light quality of nighttime supplementation, but it became clear that the higher the PPFD of nighttime supplementation, the greater. Furthermore, the effect of ascorbic acid content was examined, but the effect of nighttime supplementary light quality was not observed in Chingensai and Bekana, and the decrease in the content observed in Komatsuna was not so significant. From this, it is considered that the ascorbic acid content of Chingensai, Bekana, and Komatsuna is not significantly affected by the light quality conversion of night supplementary light.

c. Effects of nighttime blue supplementary light and daytime far-red light cut on Chingensai, Bekana and Komatsuna (Example 1)
The results of examining the effects of nighttime blue light supplementation and daytime light quality conversion on plant height, petiole length, leaf width, and leaf length are shown in FIG. In Chingensai, plant height, petiole length, leaf width, and leaf length were all increased in the + nB section than in the Control section. On the other hand, in -FR + nB plot, plant height and petiole length decreased, and no change was observed in leaf length and leaf width, but in -FR plot, plant height, petiole length, leaf width and leaf length all decreased (Fig. 9A). In Bekana, plant height, petiole length, leaf width and leaf length were all increased in the + nB group as compared to the Control group. In -FR + nB, the leaf width and leaf length increased and the petiole length decreased, but no change in plant height was observed. On the other hand, no significant difference was observed between the -FR group and the Control group (FIG. 9B). In Komatsuna, the plant height, leaf width, and leaf length increased in the + nB section than in the Control section. In the -FR + nB section of Komatsuna, as in the case of Chingensai, plant height and petiole length decreased, but no change was observed in leaf length and leaf width. In the FR group, a decrease in plant height, leaf width, and petiole length was observed (FIG. 9C). Next, FIG. 10 shows the results of examining the effects of nighttime blue light supplementation and daytime light quality conversion on the dry weight of leaves, stems, and roots. Chingensai and Komatsuna showed similar changes in leaves, stems and roots of all treatments (FIGS. 10A and 10C). The dry weight of leaves (126%), stems (163%), and roots (142%) increased in the + nB section of Chingensai, and the leaves (134%) and stems (155%) in the + nB section of Komatsuna. , Dry weight of roots (130%) increased. In -FR + nB, the dry weight of leaves increased (123% of Chingensai, 115% of Komatsuna), but no change was observed in the dry weight of roots, and the dry weight of the stem decreased (85% of Chingensai, 76% Komatsuna). -In the FR group, no change was observed in the dry weight of the leaves, but the dry weight of the stem (67% chingensai, 65% komatsuna) and the dry weight of the root (77% chingensai, 67% komatsuna) decreased. In Bekana, the dry weight of leaves, stems, and roots (154%, 193%, and 200%, respectively) increased in the + nB section, and the dry weight of leaves, stems, and roots (163%, 124%, respectively) in the -FR + nB section. 211%) increased (FIG. 10B). -No change was observed in the leaves, stems and roots in the FR group. When the influence on the specific leaf area was examined (FIG. 11), the specific leaf area decreased in all light-treated areas in Chingensai. On the other hand, in Bekana and Komatsuna, no significant difference was observed in the -FR group, but a decrease in specific leaf area (an increase in leaf thickness) was observed in the + nB group and the -FR + nB group.
The petiole length and leaf thickness (specific leaf area) and edible part dry weight were compared between Chingensai and Bekana. Both crops were irradiated with blue light only at night. Although the length increased (FIGS. 15 and 14B), a tendency to increase the petiole was also observed (FIG. 14A). Therefore, when combined with daytime far-red light cut, both crops are suppressed in petiole elongation (Fig. 14A), increased leaf thickness (Fig. 14B), and increased dry matter weight (Fig. 15), It became clear that both suppression of the patriarch and increase in edible dry weight could be achieved.

  From the above results of Comparative Examples 1 and 2 and Example 1, the light quality control method effective for suppressing the length of cruciferous leaf vegetables and increasing the dry weight of edible parts under low sunshine conditions is far from sunlight or artificial light in the daytime. It became clear that the red light was reduced and the blue light was irradiated at night. It was found that no flower buds were formed for Bekana, Komatsuna and Chingensai under the present experimental conditions. If a far-infrared light shielding material for reducing far-red light and a blue light irradiation device are introduced at the site of facility cultivation, such light quality control is considered to be possible. In addition, Chingensai, Bekana, and Komatsuna, which were studied in the examples, have high market needs because of their relatively large consumption in general households, but Hokuriku continues to be cloudy in winter by cultivating according to the method of the present invention. It is a crop that can be expected as a cultivated item for solar-powered cultivation facilities in low sunshine areas such as rural areas and fully artificial light type plant factories that have to be weakly lit due to lighting costs.

It is a graph which shows about the influence which light quality conversion of daytime has on plant height, petiole length, leaf width, and leaf length. It is a graph which shows about the influence which light quality conversion of daytime has on the dry matter weight of a leaf, a stem, and a root. It is a graph which shows about the influence which light quality conversion of daytime has on specific leaf area (leaf thickness). It is a graph which shows about the influence which the light quality conversion of nighttime supplementary light has on plant height, petiole length, leaf width, and leaf length. It is a graph which shows about the influence which the light quality conversion of night supplementary light has on the dry matter weight of a leaf, a stem, and a root. It is a graph which shows about the influence which the light quality conversion of night supplementary light has on a specific leaf area (leaf thickness). It is a graph which shows about the influence which the light quality conversion of nighttime supplementary light has on the β-carotene content. It is a graph which shows about the influence which the light quality conversion of night supplementary light has on vitamin C content. It is a graph which shows about the influence which nighttime blue light supplement and daytime light quality conversion have on plant height, petiole length, leaf width, and leaf length. It is a graph which shows about the influence which nighttime blue light supplementation and daytime light quality conversion have on the dry weight of a leaf, a stem, and a root. It is a graph which shows about the influence which nighttime blue light supplementary light and daytime light quality conversion have on a specific leaf area. It is a graph shown about the influence (PPFD150) which far-red light cut and blue light plus in the daytime have on length control. It is a graph shown about the influence (PPFD150) which the far-red light cut of daytime and blue light plus have on dry matter production of an edible part. It is a graph shown about the influence (PPFD150) which nighttime blue light supplementary light and daytime light quality conversion have on the length control. It is a graph shown about the influence (PPFD150) which nighttime blue light supplementary light and daytime light quality conversion have on dry matter production of an edible part. It is a figure which shows an example of a sunlight combined use type cultivation apparatus. It is a figure which shows an example of a complete artificial light type cultivation apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sunlight combined use cultivation device 3 Far red light shielding material 5 Blue light source 6 Leaf vegetables 9 Complete artificial light type cultivation device 10 Light source

Claims (12)

In the cultivation of leafy vegetables under low sunshine conditions with a chief, among the light having a wavelength longer than 700 nm from sunlight under low sunshine conditions, far-red light having a wavelength of at least 700 to 800 nm is reduced, and the wavelength is 400 to 500 nm at night. Method for cultivating leafy vegetables that emit blue light. In the cultivation of leafy vegetables in a fully artificial light type cultivation facility, illumination light that does not contain or reduce far-red light having a wavelength of at least 700 to 800 nm out of light having a wavelength longer than 700 nm in a time period corresponding to daytime. The cultivation method of leaf vegetables which irradiates and irradiates blue light with a wavelength of 400-500 nm in the time slot | zone equivalent to nighttime. The far-red light shielding material is used to reduce far-red light having a wavelength of at least 700 to 800 nm out of light having a wavelength longer than 700 nm from light irradiated in the daytime or a time zone corresponding to daytime. The cultivation method of leaf vegetables as described. The photosynthesis effective photon flux density of the blue light is 80 μmolm ⁻² s ⁻¹ or more, and the irradiation time of the blue light is at least 4 hours or more per night. The cultivation method of leaf vegetables as described. The method for cultivating leafy vegetables according to claims 1 to 4, wherein the irradiation period of the blue light is nighttime near dawn. The leaf vegetable is a Brassicaceae, The cultivation method of the leaf vegetable as described in any one of Claims 1-5. In a sunlight combined use type cultivation apparatus, under low sunshine conditions with a chief, far-red light for reducing far-red light having a wavelength of at least 700 to 800 nm out of daylight sunlight having a wavelength longer than 700 nm. A leaf vegetable cultivation apparatus comprising a shielding material and a light source for irradiating blue light having a wavelength of 400 to 500 nm at night. When cultivating leafy vegetables in a fully artificial light-type cultivation facility, light that does not contain or reduce far-red light with a wavelength of at least 700 to 800 nm out of light with a wavelength longer than 700 nm is emitted in a time period corresponding to daytime. An apparatus for cultivating leafy vegetables, comprising a light source that emits blue light having a wavelength of 400 to 500 nm in a time zone corresponding to nighttime. 9. The light source according to claim 8, wherein the light source includes a white light source and a far red light shielding material that suppresses transmission of a far red light component having a wavelength of 700 to 800 nm out of light having a wavelength longer than 700 nm. Leaf vegetable cultivation equipment. 9. The leaf vegetable cultivation apparatus according to claim 8, wherein the light source substantially does not include far-red light having a wavelength of 700 to 800 nm out of light having a wavelength longer than 700 nm. The photosynthesis effective photon flux density of the blue light is 80 µmolm ^-2 s ^-1 or more, and the irradiation time of the blue light is at least 4 hours per night. The leaf vegetable cultivation apparatus described. The apparatus for cultivating leafy vegetables according to any one of claims 7 to 11, wherein the irradiation time zone of the blue light is nighttime close to dawn.