JP5376667B2 - Flower seedling raising method and seedling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for raising seedling of flowering plants enabling an effective acceleration of blooming within relatively short treatment period of time and with a small amount of energy consumption. <P>SOLUTION: The method for raising seedling of flowering plants includes irradiating young seedlings after all of true leaves come out after germination with light having a peak wavelength of 400-550 nm at a low temperature of not more than 15&deg;C for 100-600 hours. The light having a peak wavelength of 400-550 nm includes the one having LED as a light sauce, and photon flux density is preferably 15-200 &mu;mol m<SP>-2</SP>s<SP>-1</SP>. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a method for raising florets, and more particularly to a method for raising seedlings for promoting the flowering of long-day plants.

  It has been found that light is more important than temperature for the flowering of flower buds, and a technique for promoting the flowering of long-day plants by long-day treatment is widely used. In the long day treatment, a growing plant is irradiated with light for a longer time than the actual day length using an electric lighting facility, and the flowering time is advanced.

  Moreover, it is known that the reaction of the plant with respect to light changes with wavelengths of the light to irradiate, for example, in patent document 1, the method of accelerating | stimulating flower bud formation by irradiating the blue light which has the maximum value in wavelength 400-500 nm Is disclosed, and it is described that light in the red wavelength range of 600 to 800 nm inhibits flower bud formation. Patent Document 2 discloses a method for promoting flowering in which a constant temperature bath is used to irradiate substantially blue-green light having a peak wavelength of 500 to 525 nm in accordance with the day length from the seedling stage of a plant.

JP 2001-258389 A Japanese Patent No. 4123875

  All of the above-described conventional techniques are techniques for irradiating a plant with light in accordance with the day length when it is flowering, and it is necessary to irradiate light for a relatively long time from seedling to bud or flowering. For example, in the technique described in Patent Document 1, it has been reported that light irradiation was performed for 3 months or 40 days. Such long-term light irradiation leads to an increase in power cost and management cost. Moreover, since the conventional technique performs the long-day process for promoting flowering in the winter when the temperature is low, a large amount of energy must be consumed to maintain the temperature.

  The present invention provides a method for growing a flower bud that can effectively promote flowering in a relatively short treatment period and with a small amount of energy consumption.

Specifically, the method for growing florets of the present invention is a method for raising florets for raising seedlings after germination in a controlled environment. It is characterized in that light having a peak wavelength of 400 to 550 nm is irradiated for a period of 100 hours or more and 600 hours or less at a low temperature of 15 ° C. or less.
The light having a peak wavelength of 400 to 550 nm is preferably light using an LED as a light source. The photon flux density is preferably 15 to 200 μmol · m ⁻² · s ⁻¹ .

  The present invention also includes a chamber for storing seedlings before planting, temperature adjusting means for adjusting the temperature in the chamber, means for irradiating the seedlings with blue light having a peak wavelength of 400 to 550 nm, and the temperature adjusting means. And a seedling system comprising a control means for controlling the light irradiation means. In this seedling raising system, the control means controls the temperature adjusting means so that the temperature in the chamber is 15 ° C. or lower for a fixed period of up to 3 weeks, and the irradiation time per day is 14 for a fixed period. The light irradiating means is controlled so as to be more than time. The light irradiation means preferably includes an LED device.

  The flower seedling raising method of the present invention is based on a mechanism completely different from the promotion of photosynthesis by conventional long-day treatment, and the stimulation of irradiation with light of a specific wavelength at a low temperature is applied during a limited period of the seedling stage of the flower bud. By providing, the growth and the number of flowers obtained by long-term long-day treatment or low-temperature treatment can be ensured in a short time.

The figure which shows the outline | summary of the apparatus which implement | achieves the seedling raising system of this invention The graph which shows the difference in the flower arrival days by the test plot of Example 1, and a processing period The graph which shows the difference in the number of flowers by the test plot and processing period of Example 1 The graph which shows the difference in the plant length by the temperature of Example 1 The graph which shows the difference of the flower arrival days by the test plot of Example 2, and a processing period The graph which shows the difference in the number of flowers by the test plot and processing period of Example 2

Hereinafter, embodiments of the method for raising florets of the present invention will be described.
The seedling-raising method of the present invention is applied to long-day plants such as asteraceae such as asters, urchinaceae such as carnation, oleanders such as campanula, and buttercups such as Larkspur. These long-day plants are usually sown in a seedling tray such as a plug tray, and are planted after a predetermined period of time has passed since the true leaves are arranged. In the present invention, light irradiation at a low temperature is performed on young seedlings from the time when the true leaves are arranged until the planting. From sowing until the true leaf is ready, use appropriate seedling culture soil according to the plant, and manage at natural temperature (under 20 ° C) at normal temperature. In addition, “the true leaf comes out” means a state in which at least two true leaves have come out, and varies depending on the plant, but usually about 2 to 5 true leaves when about one month has passed since sowing. Get out. If light irradiation is performed at a low temperature before the true leaves are completed, the hypocotyl is too long.

  Although the most suitable treatment period varies depending on the plant to be applied, the treatment period by light irradiation at a low temperature is generally 100 hours or more and 600 hours or less, preferably 150 hours or more and 500 hours or less, more preferably 350 hours or less. By setting the treatment period to 100 hours or longer, it is possible to harvest plants with a large number of flowers in a short number of days. However, if the treatment time exceeds 600 hours, the number of flower arrivals is accelerated but the number of flowers tends to decrease. Therefore, the treatment time preferably does not exceed 600 hours.

  The temperature is 15 ° C. or lower, preferably 4 ° C. or higher and 15 ° C. or lower. By setting the temperature to 4 ° C. or higher, the number of days to flower can be shortened while preventing the seedlings from freezing. Moreover, by setting it as 15 degrees C or less, plant height can be prevented and a highly productive plant can be grown. In a normal greenhouse, for example, when the temperature falls by 2 to 3 ° C. from 15 ° C., it is controlled to raise the chamber temperature using heating means, but during the daytime when sunlight is received, the temperature rises to 25 ° C. or higher even in winter. To do. The method of the present invention does not include an environment that includes a state where the temperature is 15 ° C. or lower and a state that exceeds 15 ° C., and always limits the environmental temperature of the seedling to 15 ° C. or lower.

Such control of the environmental temperature is performed by, for example, installing a seedling plug tray in a chamber that can be shielded from sunlight, and managing the temperature in the chamber using outside air or cooling means such as a cooler as necessary. Can be realized.
Further, the temperature does not need to be constant as long as it is within the above-described temperature range, and may vary within a range of about ± 5 ° C., for example.

  As light to be irradiated, blue light having a peak wavelength of 400 to 550 nm, preferably 420 to 510 nm is used. It is possible to use a white light source such as a sodium lamp or a fluorescent lamp by using a filter or the like as a light source of such light, but an LED that generates light in a relatively narrow wavelength range in terms of energy efficiency Is preferred.

The photon flux density of the irradiation light is 15 to 200 μmol · m ⁻² · s ⁻¹ . When the photon flux density is less than 15 μmol · m ⁻² · s ⁻¹ , a significant effect of light irradiation cannot be obtained. In addition, even if it exceeds 200 μmol · m ⁻² · s ⁻¹ , the effect is not changed and saturation is achieved. Therefore, it is preferably 200 μmol · m ⁻² · s ⁻¹ or less from the viewpoint of energy efficiency.

  The irradiation time is preferably a long day state. Specifically, the light irradiation is 14 hours or longer, preferably 18 hours or longer, more preferably full-day irradiation. The longer the irradiation time per day, the more effective integrated dose can be achieved in a short time, and the overall number of flower days can be accelerated.

  The mechanism of flowering promotion by irradiation with light of a specific wavelength at low temperatures is not clear, but unlike photosynthesis promotion by long-day treatment using sunlight or alternative light, temperature and By irradiating with a specific wavelength, it is considered that the seedlings are strongly stimulated to promote growth and flowering.

  After light irradiation under low temperature, seedlings are planted. The environment after planting is not particularly limited, and may be room temperature, or may be performed by a conventional cultivation method such as growing in a greenhouse controlled in a temperature range of about 15 ° C to 25 ° C. According to the present invention, by performing the light irradiation treatment at a low temperature only for a limited period of the seedling stage, it is possible to harvest a flower having a large number of flowers and high merchantability in a short growing period.

Next, an embodiment of the seedling raising system of the present invention will be described.
FIG. 1 is a view showing an outline of an apparatus for realizing a seedling raising system of the present invention. This apparatus 10 maintains a seedling raising chamber 20, an LED light source 30 installed in the chamber, and a predetermined temperature in the chamber. And a control unit 50 for controlling the operation of the LED light source 30 and the temperature adjusting means 40. A shelf 60 for placing a seedling raising tray after sowing is provided in the chamber 20 as necessary. The seedling tray is a plug tray or the like in which a large number of pots are arranged and integrated, and is used for growing seedlings from sowing to planting. The seedling raising system of the present invention is applied to seedlings of long-day plants in a state where seedlings are sown and germinated in a seedling tray containing seedling culture soil, and about 2 to 5 true leaves have emerged.

  In the embodiment shown in FIG. 1, a plurality of LED light sources 30 are installed in the chamber 20 so that the seedling tray is uniformly irradiated with light. The power source (not shown) of the LED light source 30 is on / off controlled by the control unit 50. As the LED light source, for example, a light source that emits blue light having a peak at a wavelength of 400 to 550 nm such as UB5306X, UC5306X, or the like (Stanley Electric Co., Ltd.) is used. The seedling raising system of the present invention may include a light source device for illumination in addition to the LED light source having the wavelength described above.

  In the chamber, as the temperature adjusting means 40, for example, a cooling means 41 such as a cooler, a thermometer 42 for detecting the temperature in the chamber, a fan 43 for making the temperature in the chamber uniform, and the like are provided. . The controller 50 receives an electric signal corresponding to the temperature in the chamber detected from the thermometer 42, operates the cooling means 41 when the temperature in the chamber exceeds a predetermined temperature, and the temperature in the chamber is substantially constant. Control to be kept at.

  The control unit 50 receives input of conditions such as a time (on time for one day) and a period (processing period) for turning on the LED light source 30 and a set temperature via an input unit (not shown). Based on the above, the LED light source 30 and the temperature adjusting means 40 are controlled. In this embodiment, the on time is set to 14 hours or longer, the on period is set to 600 hours or shorter, and the set temperature is set to 5 to 15 ° C.

The control unit 50 starts operating when a seedling tray on which seedlings with true leaves are planted is carried into the chamber 20, and maintains the temperature in the chamber at a low temperature based on conditions set via the input means. At the same time, the LED light source is turned on. After the set treatment period has elapsed, the seedlings are planted from the seedling tray to a cultivation house or the like.
According to the seedling raising system of the present invention, it is possible to perform treatment (low temperature treatment and light irradiation of a specific wavelength) under automatically controlled conditions for a long-day plant in the seedling stage, It can contribute to the early harvest time.

  Examples of the growth method of the present invention will be described below.

<Example 1>
Campanula "Champion Pink" (Chrysantaceae) was sown in a 72-hole plug tray and raised in a greenhouse for general cultivation. After 4 to 5 true leaves were collected, they were grown for 1 to 4 weeks in 4 test plots with different light and temperature conditions. After growing for 1 to 4 weeks in each test section, the seedlings were planted in a No. 3.5 pot and grown in a natural day length in a greenhouse for general cultivation to confirm the flowering state.
Test section 1: Inside greenhouse for general cultivation (temperature 15 ° C or higher, sunlight)
Test area 2: Inside greenhouse for general cultivation (temperature of 15 ° C or higher, LED irradiation all day)
Test section 3: Growth chamber (temperature 5 ° C., chamber illumination 10 hours long)
Test section 4: Growth chamber (temperature 5 ° C, LED irradiation all day)

In addition, the conditions of the test area 1 are the same as the conventional cultivation method. The LEDs used in the test sections 2 and 4 are LEDs that emit blue light having a peak wavelength of 465 nm (UB5306X: Stanley Electric Co., Ltd.), and the irradiation intensity was 50 μmol · m ⁻² · s ⁻¹ . In test section 3, the illumination time was set to the time (10 hours) matched to the day length of sunlight in test section 1.

  About the seedling which performed the process by each test plots 1-4, the number of days (flower arrival days) until flowering from sowing and the number of flowers (number of flowers) was measured. The results of the number of flower arrivals are shown in Table 1 and FIG. 2, and the results of the number of flowers are shown in Table 2 and FIG.

<Days to flower>
FIG. 2 is a graph showing the number of flower arrival days for each processing period in each test section. As can be seen from the results shown in Table 1 and FIG. 2, the number of flower arrival days was not significantly different from that of the conventional method (test group 1) only by low-temperature treatment, but the number of flower arrival days was accelerated by irradiation with LED light. The longer it was, the shorter the number of flower days arrived. In particular, when LED light was irradiated at room temperature, the number of flower days was significantly shortened.

<Number of flowers>
FIG. 3 is a graph showing the number of flower arrival days for each processing period in each test section. As can be seen from the results shown in Table 2 and FIG. 3, when the LED light was irradiated at room temperature, the number of flowers was drastically reduced and there was no commercial value. On the other hand, when the low-temperature treatment and LED light irradiation were used together, the number of flowers did not decrease if the treatment was for a short time.

<Plant head>
Table 3 and FIG. 4 show the results of comparing plant lengths at different environmental temperatures when LED light irradiation is performed.

  As shown in the figure, the plant length tends to become longer as the temperature of the seedling environment increases, and when it is irradiated with LED light without low temperature treatment, the plant length grows as the treatment period prolongs, and the merchantability as a seedling is increased. Declined. On the other hand, when the low temperature treatment and LED light irradiation were combined, no chief was observed even if the treatment period was 4 weeks.

<Conclusion>
From the above results, it was found that, for campanula, cut flowers with a large number of flowers can be harvested in a short flowering period by performing low temperature treatment at a temperature of 15 ° C. or lower and LED light irradiation for about 2 weeks at the seedling stage. In addition, the seedling quality at the time of planting was good with no chief.

<Example 2>
The aster “Matsumoto Scarlet” (Asteraceae) was sown in a seedling tray similar to that in Example 1, and the seedlings were grown in a greenhouse with 15 ° C. ventilation (no heating). After 4 to 5 true leaves were collected, they were grown for 1 to 4 weeks in 4 test plots with different light and temperature conditions. After growing for 1 to 4 weeks in each test section, the seedlings were planted in a No. 3.5 pot and grown in a natural day length in a greenhouse with 15 ° C. ventilation and 10 ° C. heating to confirm the flowering state.
Test section 1: Inside the greenhouse (15 ° C ventilation 10 ° C warming, sunlight)
Test Zone 2: Greenhouse (15 ° C ventilation, 10 ° C heating, LED irradiation all day)
Test section 3: Growth chamber (temperature 5 ° C., chamber illumination 10 hours long)
Test section 4: Growth chamber (temperature 5 ° C, LED irradiation all day)

The conditions of the test area 1 are the same as the conventional cultivation method. In the test groups 2 and 4, an LED emitting blue light having a peak wavelength of 465 nm was used, and the irradiation intensity was 50 μmol · m ⁻² · s ⁻¹ . In test section 3, the illumination time was set to the time (10 hours) matched to the day length of sunlight in test section 1.
About the seedling which performed the process by each test plots 1-4, the number of days (flower arrival days) until flowering from sowing and the number of flowers (number of flowers) was measured. The results are shown in Table 4 and FIGS.

<Days to flower>
FIG. 5 is a graph showing the number of flower arrival days for each processing period in each test section. As can be seen from this result, when only low-temperature treatment was performed (test group 3), the number of flower arrival days tended to be slightly longer than in the conventional method (test group 1), but when LED light was irradiated ( In the test plots 2, 4), the number of flowers reached earlier, and the longer the period, the shorter the number of flowers arrived. In particular, when LED light was irradiated at room temperature, the number of flower days was significantly shortened.

<Number of flowers>
FIG. 6 is a graph showing the number of flower arrival days for each processing period in each test section. As can be seen from this result, when the LED light was irradiated at room temperature (15 ° C) (test zone 2), the number of flowers decreased drastically when the seedling period in the test zone environment reached 2 weeks. When irradiation was used in combination, the number of flowers did not decrease in the treatment for 2 weeks, and the number of flowers decreased dramatically in 3 weeks.

<Plant head>
As for the plant length, as in Example 1, when the LED light was irradiated at 15 ° C., the length of the plant length was increased as the treatment period was prolonged, whereas the commercial value as a seedling was reduced. When low temperature treatment and LED light irradiation were combined, no chief was observed even after 4 weeks of treatment.

<Conclusion>
From the above results, it is possible to reduce the number of flower days for asters compared to the conventional method by performing low temperature treatment at a temperature of 15 ° C. or lower and LED light irradiation for 2 to 3 weeks at the seedling stage. It turned out that a large number of cut flowers can be harvested. In addition, the seedling quality at the time of planting was also good with no chief.

  According to the present invention, by performing a combination of low-temperature treatment and light irradiation for a limited period in the seedling period of long-day plants, flowers having a high number of flowers and high merchantability can be produced one to two months earlier than before. It becomes possible to harvest cut flowers. Moreover, the plant grown by the method of the present invention is expected to be used as a pot if the plant height does not elongate.

DESCRIPTION OF SYMBOLS 10 ... Raising system, 20 ... Chamber, 30 ... LED light source, 40 ... Temperature adjustment means, 41 ... Cooling means, 42 ... Thermometer, 43 ... Fan, 50. ..Control unit, 60 ... shelf.

Claims (7)

A method for raising a flower bud in which a seedling after germination is bred in a controlled environment,
A method for raising a flower bud, characterized by irradiating seedlings after germination of main leaves with light having a peak wavelength of 400 to 550 nm for a period of 100 hours to 600 hours at a low temperature of 15 ° C. or less. A method for raising a flower bud according to claim 1,
The flower seedling raising method, wherein the light having a peak wavelength of 400 to 550 nm is light using an LED as a light source. A method for raising a flower bud according to claim 1 or 2,
A method for raising florets, wherein the light having a peak wavelength of 400 to 550 nm has a photon flux density of 15 to 200 μmol · m ⁻² · s ⁻¹ . A method for raising a flower bud according to any one of claims 1 to 3,
The method for raising florets, wherein the irradiation with light at a low temperature is 14 hours or more per day. A method for raising a flower bud according to any one of claims 1 to 4,
The method for raising florets, wherein the florets are long-day plants. A chamber for storing seedlings before planting, temperature adjusting means for adjusting the temperature in the chamber, means for irradiating the seedlings with blue light having a peak wavelength of 400 to 550 nm, and the temperature adjusting means and the light irradiating means. A seedling system comprising a control means for controlling, wherein the control means controls the temperature adjusting means so that the temperature in the chamber becomes 15 ° C. or lower for a fixed period of up to 3 weeks, and The seedling raising system characterized by controlling the said light irradiation means so that the irradiation time per day of the said blue-type light may become 14 hours or more during a fixed period. The seedling raising system according to claim 6,
The seedling system, wherein the light irradiation means includes an LED device.

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