KR101386930B1 - Method for growing lettuce using artificial light source and its photoperiod in closed-type plant production system - Google Patents

Abstract

The present invention relates to a lettuce cultivation method using an artificial light source and its photoperiod in a hermetic plant production system. Lettuce cultivation method according to the present invention by providing the optimum wavelength band and photoperiod of the artificial light source for lettuce growth to excellent lettuce cultivation efficiency, it can be usefully used in large scale hermetic plant production system.

Description

Method for growing lettuce using artificial light source and its photoperiod in closed-type plant production system}

The present invention relates to a lettuce cultivation method using an artificial light source and its photoperiod in a hermetic plant production system.

Recently, the number of consumers demanding the supply of safe agricultural products is increasing, the importance of safe production of high-quality horticultural crops is emphasized due to the abnormal climate phenomenon, and the food security is becoming an important problem due to the soaring grain prices. Interest is growing. In addition, research is being conducted to provide safe foods by introducing advanced quality control technology in agricultural products and to supply high value-added food materials by combining agriculture, commerce and industry.

The plant production system refers to a system that automatically produces continuous crops regardless of season or place by artificially controlling environmental conditions such as light, temperature, humidity, carbon dioxide concentration, and culture solution in a controlled facility (Takatsuji, 2008). In other words, it is a system that produces plants by using high environmental control, which can produce plants of uniform quality throughout the year while maintaining optimal cultivation environment within the facility (Lee et al., 2004; Park and Kim). , 1998). Currently, researches on plant production systems are being conducted in various parts of the world, but no clear definition has been made. Plant production systems are generally classified into fully controlled plant production systems, solar-combined plant production systems, and solar-utilized plant production systems, depending on the type of light source used. Under these conditions, the light utilization efficiency can be improved by 2 to 3 times, and plant growth can be promoted, and since it is not influenced by pests and outdoor air, it is possible to produce high quality seedlings under uniform growth conditions (Kozai, 2007). . As such, it is urgent to find environmental factors such as the type of artificial light source and the light irradiation time in order to realize a practical plant production system for plant cultivation.

In general, a plant production system uses fluorescent lamps or metal halides rather than high-pressure sodium lamps that generate heat and energy loss due to light emission (Kozai, 2007; Tadahisa et al., 2004). The LED (light emitting diode) that can compensate for this problem is environmentally friendly and lightweight because it has no mercury component, which has excellent power saving, long life, and simple driving circuit. (Hwang et al., 2004). As such, the use of specific minerals has the advantage of being able to control customized minerals according to the cultivation purpose of vegetable cultivation in the plant production system.

Growth Accelerating Effect in Red Light (Nishimura et al., 2006; Nishimura et al., 2009; Nishioka et al. 2008) and Effects of LED on Light Growth of Young Leaf Lettuce (Lee et al., 2010) ) Has been reported. However, many research results are mainly focused on red light or blue light, and research results on white LEDs that can promote plant photosynthesis and growth by making various wavelength bands are insufficient.

Light is a very important factor in the growth and development of plants. The use of high energy light increases the productivity of various vegetables (Dorais et al., 1990). Lettuce has been frequently used at home and abroad as a model plant suitable for studying the plant's response to light in the facility (Dougher and Bugbee, 2001; Kim et al., 2004). It is known as a suitable plant for the production method of the plant production system using.

Therefore, the present inventors, while studying the effect on the growth of lettuce according to the type (fluorescent lamp, white LED) and light irradiation time in the hermetic plant production system, by irradiating a fluorescent lamp as an artificial light source to find the optimum wavelength band for lettuce growth The present invention was completed by confirming that there is a high quality, high yielding effect, and at the same time further improving the growth rate of lettuce in the plant production system when adjusting photoperiod.

An object of the present invention is to provide a lettuce cultivation method using an artificial light source and photoperiod in a hermetic plant production system.

In order to achieve the above object, the present invention provides a method for growing lettuce using an artificial light source and photoperiod and a hermetic plant production system using the same.

Lettuce cultivation method according to the present invention can be useful for high-quality, high yield of lettuce by providing the optimum wavelength range and photoperiod of the artificial light source for lettuce growth by improving the rate of lettuce growth in the plant production system.

1 is a view showing the hermetic plant production system of the present invention [A is a control system, B is an artificial light source LED lamp, C is a recirculation irrigation system, D is a nutrient solution tank, E is a pump, F is a cooling and heating system, G Slidax].
Figure 2 is a view showing a view on the lettuce cultivation environment.
3 is a diagram illustrating absolute light emission of spectral distribution of artificial light sources for each wavelength band.
Figure 4 is a diagram showing the chlorophyll fluorescence according to the artificial light source and photoperiod of lettuce in a closed plant production system.
5 is a view showing the total anthocyanin content according to the artificial light source and photoperiod of lettuce in a closed plant production system.
6 is a view showing the effect on lettuce growth according to the artificial light source and photoperiod in the hermetic plant production system.

According to the present invention,

1) seeding the lettuce in a plug tray containing rock wool pellets and germinating;

2) cultivating the germinated lettuce under a fluorescent lamp of a closed plant production system; And

3) to provide the artificial light source and the lettuce cultivation method using a photoperiod comprising the step of irradiating the lettuce with a fluorescent lamp with a lighter of 12 to 24h / day to formulate the cultivated lettuce.

Hereinafter, the present invention will be described in detail.

The lettuce cultivation method according to the present invention is characterized in that after germinating the seeds by germination, cultivated germinated lettuce under a fluorescent lamp of a closed plant production system, and then formally irradiated a fluorescent lamp with a photoperiod of 12 to 24 h / day do.

The size of the plug tray is preferably 60 cm x 41 cm x 5 cm.

The germination is preferably germinated for 3 days or more in a constant temperature germination chamber of 20 ℃.

It is preferable that the irradiated fluorescent lamp has a peak wavelength at 300 to 800 nm.

It is preferable that the light quantity of the said fluorescent lamp is 0.50-9.00 dl / cm <2> / nm.

Light intensity of said fluorescent lamp is 100μ㏖ · m ^-2 · s ^- is preferably ^1.

The fluorescent lamp is preferably irradiated with any photoperiod selected from the group consisting of 12, 18 and 24h / day.

The lettuce cultivation method according to the present invention includes an optical wavelength band suitable for plant growth, and enhances photosynthetic efficiency of lettuce by irradiating a fluorescent lamp using an appropriate photoperiod, which causes less stress to plants even during continuous light irradiation. It can increase leaf area, leaf number, and chlorophyll content.

The present invention also relates to (A) control system, (B) artificial light source fluorescent lamp, (C) recirculating irrigation system, (D) nutrient solution tank, (E) pump, (F) cooling and heating system, (G) voltage regulator (slidacs) )

The control system (A) is characterized in that the system for controlling the photoperiod 12 to 24h / day,

The artificial light source fluorescent lamp (B) provides a closed plant production system, characterized in that it has a peak wavelength at 300 to 800nm.

The structure of the hermetic plant production system is shown in FIG.

The control system (A) includes automatic control by designating conditions of temperature, photoperiod, nutrient solution and light source according to the growth pattern of lettuce, and photoperiod 12/12, 18 / 6 and 24/0 (bright / memory).

The artificial light source fluorescent lamp (B) includes a linear fluorescent lamp, an annular fluorescent lamp, a PL fluorescent lamp, a bulb fluorescent lamp, but a linear fluorescent lamp is preferable.

The (C) recycle watering system is preferably adjusted to the concentration of nutrient solution, watering time and watering frequency.

(D) The nutrient solution tank is preferably stored in a constant concentration of nutrient solution is automatically controlled from a control system or a recirculation irrigation system.

The (E) pump is preferably introduced for the geothermal heat pump system for temperature management inside the hermetic plant production system.

It is preferable that the said (F) cooling / heating system maintains the temperature suitable for lettuce cultivation automatically using a heat pump.

The (G) voltage regulator changes the input AC voltage to a desired size to create a new AC power source, and is controlled by a control system, and includes a capacity of 1 kW, 3 kW and 5 kW.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided only for the purpose of easier understanding of the present invention, and the present invention is not limited by the examples.

[ Example  1]: cultivation environment of lettuce

The test material was 'actual red axis' lettuce ( Lactuca) sativa L. 'Seonhong Jeokchukmyeon') was used and sown on January 14, 2011 in a 240-hole seedling plug tray (60 cm × 41 cm × 5 cm) containing rock wool pellets (UR rock wool). After 3 days of germination in a constant temperature germination chamber (DS-10L-2, Dasol Scientific, Korea) at 20 ° C, the fluorescent lamps of Philips Co. Ltd. (C1200H3, FC Poibe Co. Ltd., Korea) Ltd., the Netherlands).

On the 27th day after planting, in the closed plant production system installed in Gyeongsang National University horticulture laboratory, lettuce was planted at 20 cm × 20 cm in 3 treatment light sources and 3 cycles of light irradiation time. Was formulated. The lettuce used for the experiment was selected as a uniform seedling with an average height of 10.6cm and an average live weight of 6.5g, and was set on February 9, 2011. Artificial light sources include white LEDs (WL # 1, Hepas Co. Ltd., Korea), white LEDs (WL # 2, FC Poibe Co. Ltd., Korea), and fluorescent lights (FL, Philips Co. Ltd., Netherlands). Using this, light / memory was set to 12/12, 18/6, and 24/0, respectively, to adjust the light irradiation time. The length of the artificial light source was 1,200mm and the same size was used.

The cultivation environment of the hermetic plant production system was controlled at a temperature of 21 ± 2 ° C, a relative humidity of 60 ± 10%, and a luminous intensity of 100μmol · m ^-2 · s ^-1 , and was cultivated for a total of 23 days after planting. Lettuce was cultivated by distillate recycling hydroponic cultivation method, and prepared Sonneveld lettuce nutrient solution was used for irrigation. The components and concentrations of the prepared nutrient solution are shown in Table 1.

ingredient Concentration (mgL- ¹ ) ingredient Concentration (mgL- ¹ ) Ca (NO ₃ ) ₂ .4H ₂ O 1,014.8 K ₂ SO ₄ 43.5 KNO ₃   919.1 H ₃ BO ₃   1.89 Fe-EDTA   15.3 CuSO ₄ · 5H ₂ O   0.20 KH ₂ PO ₄  272.0 Na ₂ MoO ₄ .2H ₂ O   0.13 MgSO ₄ 4H ₂ O  196.8 ZnSO ₄ .7H ₂ O   1.14 NH ₄ NO ₃  104.0

The prepared nutrient solution was supplied by adjusting the pH to 6.5 and EC to 1.5 dS · m ⁻¹ .

The scene for this experiment is shown in FIG. 2.

[ Example  2] : In artificial light source  Following Light wavelength

In order to analyze the light wavelength according to the artificial light source, the white LED (WL # 1), white LED (WL # 2) and fluorescent light (FL) light source are irradiated, and the spectroradiometer (RPS-900R, International Light Co. Ltd., USA) was installed to measure the light wavelength.

The measured value is shown in FIG. 3.

As shown in FIG. 3, it was confirmed that the fluorescent lamp is a light source having various light wavelength bands for plant growth between 300 nm and 800 nm compared to the white LED light source.

[ Example  3]: Artificial light source  Chlorophyll Fluorescence Measurement by Type and Photoperiod

To investigate the chlorophyll fluorescence according to the type of artificial light source and photoperiod, it was measured based on the second leaf at 27 days after planting. The fluorescence of chlorophyll in lettuce was measured using a portable chlorophyll fluorescence spectrometer (PAM-2100, Heinz Walz GmbH, Germany) at the same location in three or more leaves per lettuce.

The measured value is shown in FIG. 4.

As shown in FIG. 4, the chlorophyll fluorescence value (Fv / Fm) decreased with increasing light irradiation time, and was highest as 0.77 in the treatment group grown with 12/12 (light / dark) light irradiation time under a fluorescent light source. In the 24/0 (light / memory) irradiation time treatment group of the white LED (WL # 1) light source, the lowest was 0.37. If the chlorophyll fluorescence value is too low, it can be estimated that the plant is exposed to stress or has entered the aging stage. Therefore, continuous light irradiation using white LEDs (WL # 1 and WL # 2) is more effective than plants using fluorescent lamps. It was confirmed that it can induce high stress and promote aging. When the light irradiation time is adjusted through this, it was confirmed that the fluorescent light is the most suitable light source for the cultivation of lettuce.

[ Example  4] : Artificial light source  Investigation of Total Anthocyanin Content in Lettuce by Different Kinds and Photoperiods

In order to investigate the total anthocyanin content in lettuce according to the type of artificial light source and photoperiod, 2g of lettuce leaves were taken in vivo, and the extract was mixed with 95% ethanol and 1.5N hydrochloric acid at 85:15 (v / v). 1 mL of 2 mL addition and crushed solution was taken in a microtube. After storage for 24 hours at 4 ℃ dark conditions, the supernatant obtained by centrifugation at 13,000rpm for 20 minutes was diluted 1: 5 and the absorbance was measured using a spectrophotometer (Libra S22, Biochrom, United Kingdom) at 535nm.

The measurement results are shown in Fig.

As shown in FIG. 5, the total anthocyanin content is about 3 times higher in the fluorescent lamp 24/0 (light / memory) treatment than the white LED light source treatment, and the total anthocyanin content according to red expression is significantly higher in the fluorescent lamp treatment. Shows positive correlation. In addition, the white LED (WL # 2) and fluorescent (FL) light sources had the highest total anthocyanin content in the lettuce treated by adjusting photoperiod at 24/0 (light / memory) time, and the white LED (WL # 1) light source It was the highest in the treated group by adjusting photoperiod to 18/6 (light / memory).

On the other hand, Nishimura et al. (2006) The growth is promoted and anthocyanin content of shiso (Perilla frutescens Britt.) From a light source with a red light has a reported that the increase in the mixed light of the red light and blue light. In particular, blue light and UV-A play a large role in the expression of anthocyanin pigments because cryptochromes act as photoreceptors of these light wavelengths (Giliberto et al., 2005; Ninu et al., 1999). Known. Lee et al. (2010) also reported that it is necessary to adjust the ratio of red light and blue light to produce high-color products while maintaining the productivity of lettuce.

Therefore, UV-A (300-400nm) wavelength range was investigated at the wavelength of fluorescent light from the results of the anthocyanin content in lettuce treated with white LED light source as compared to the fluorescent light treatment, but the wavelength related to the expression of anthocyanin was found in the LED light source. It can be seen that the cause is the irradiation of the light source showing the wavelength distribution only in the band of 300 to 800 nm which is not included at all.

[ Example  5]: Artificial light source  Growth and Quality Measurement of Lettuce by Kind and Photoperiod

In order to investigate the growth and quality of lettuce according to the type of artificial light source and photoperiod, the height, leaf length, leaf width, number of leaves, leaf area (LI-3100, LI-COR Inc., USA) and chlorophyll content (SPAD 502, Minolta, Japan), maximum root length, ground weight and underground weight, dry weight, total anthocyanin content, chlorophyll fluorescence (Fv / Fm), photosynthetic capacity, porosity, transpiration rate and CO ₂ The amount of absorption was measured.

The measured values are shown in Tables 2 to 4.

Light source Guangzhou
(Specification / memorization) Plant size
(cm) Max root
(cm) Live weight (g) (G) in building Ground Underground Ground Underground WL # 1 12/12 14.9f ^y 32.0b 22.6d 2.0c 0.8d 0.07d 18/6 15.8d-f  32.5ab 31.1c 3.4b 1.3c 0.11c 24/0 17.9bc 26.3c 40.1b 3.5b 1.8b 0.19a WL # 2 12/12 15.2ef 27.7c  21.7de 1.8c 0.9d 0.07d 18/6 16.2de 31.7b 38.9b 4.3a 1.7b  0.13bc 24/0 18.1b 31.8b 47.6a 4.6a 2.2a 0.19a FL 12/12 15.2ef  35.0ab 17.4e 1.5c 0.8d 0.05d 18/6 18.1b 36.0a 30.9c 3.0b 1.5c 0.12c 24/0 20.8a  33.8ab 52.3a 4.6a 2.2a 0.16b

Light source Guangzhou
(Specification / memorization) Leaf
(Cm) Leaf width
(Cm) Leaf area
(Cm / plant) ground game Chlorophyll content
(SPAD)
WL # 1 12/12 13.7cd ^y 12.9b  1,505.1bc 6.2b 14.1b-d 18/6 14.7c 14.4b 1,671.7b 6.1bc 12.2d 24/0 15.8b 16.0ab 1,318.7de  6.1bc  13.5cd
WL # 2 12/12 12.9d 12.8b 1,167.8e 5.3c  13.2cd 18/6  13.8cd 23.7a 1,257.9e 6.3b  16.0ab 24/0 14.7c 16.9ab 1,599.6bc 6.3b  14.1b-d
FL
12/12 13.8c  11.4ab 1,264.3e 7.9a 14.9a-c 18/6 14.6c 13.2b 1,440.4cd 7.9a 16.5a 24/0 18.3a 14.2b 1,990.6a 7.9a  15.6a-c

Light source Guangzhou
(Specification / memorization) photosynthesis
^{_{(μmolCO 2 · m -2 · s}} -1) Pore Conductivity
^{_{(molH 2 O · m -2 ·}} s -1) Rate of increase
^{_{(molH 2 O · m -2 ·}} s -1) CO ₂
Absorption amount
(μmolmol- ¹ ) WL # 1 12/12 6.38ab ^y  0.0016ab  0.036ab  7.67ab 18/6 7.49a 0.0036a  0.068ab 9.03a 24/0 1.61d 0.0005b 0.010b 1.94d WL # 2 12/12  5.89ab  0.0027ab  0.067ab  7.01ab 18/6  3.17cd  0.0024ab  0.060ab  3.82cd 24/0 2.56d  0.0020ab  0.054ab 3.09d FL 12/12  4.56bc  0.0024ab  0.061ab  5.41bc 18/6  4.51bc  0.0019ab  0.058ab  5.36bc 24/0  6.25ab  0.0030ab 0.092a  7.59ab

As shown in Table 2, the live weight of the above-ground and underground areas and the buildings of the above-ground area were the highest in the treatment zone where the photoperiod of the fluorescent (FL) light source was 24/0 (bright / dark), so that the fluorescent light was wider than the white LED light source. This variety can be seen that the light source showing a positive effect on plant growth.

As shown in Table 3, the leaves were the highest in the treatment group with photoperiod 24/0 (light / memory) of the fluorescent light source, and all the artificial light sources increased with increasing light irradiation time, especially the leaf area and number of leaves. , The highest chlorophyll content, it can be seen that the fluorescent light source is an efficient artificial light source for lettuce growth.

As shown in Table 4, the porosity, transpiration rate and CO ₂ of each artificial light source according to the treatment type and light irradiation time There was no obvious tendency in the amount of absorption.

In addition, through Examples 2 to 4, since it was confirmed that the light source suitable for the cultivation of lettuce is a fluorescent lamp, the photosynthetic efficiency after irradiation by adjusting the photoperiod of the fluorescent lamp to bright / memory 12/12, 18/6 and 24/0, respectively The highest photoperiod condition was identified.

Claims (6)

Fluorescent lamps having peak wavelengths at 300 to 800 nm have a light quantity of 0.50 to 9.00 μs / cm 2 / nm, a light intensity of 95 to 105 μmol · m ⁻² · s ⁻¹ , and a photoperiod of 20 to 24 h / day Irradiating to, and the step of cultivating lettuce under the conditions of temperature 21 to 23 ℃, lettuce cultivation method. The method of claim 1,
The lettuce cultivation method further comprises the step of seeding the lettuce seedlings in a plug tray containing rock wool pellets, lettuce cultivation method. delete delete delete delete

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