What are the functions of LED grow lights?
Knowledge about LED grow lights:
1. The color temperature and lumen of the plant light
The color temperature and lumens of plant lamps can be seen from the human eye, and the photosynthesis of plants does not look at the color temperature and lumens.
2. The effect of spectral range on plant physiology (please refer to the chart in Figure 3)
280 ~ 315nm ——> minimal impact on morphology and physiological processes
315 ~ 400nm ——> Less absorption of chlorophyll, affecting photoperiod effect and preventing stem elongation
400 ~ 520nm (blue)—>The absorption ratio of chlorophyll and carotenoids is the largest, and it has the greatest impact on photosynthesis
520 ~ 610nm (green)—>The absorption rate of the pigment is not high
610 ~ 720nm (red)—>The absorption rate of chlorophyll is low, which has a significant impact on photosynthesis and photoperiod effect
720 ~ 1000nm ——>Low absorption rate, stimulate cell elongation, affect flowering and seed germination
＞1000nm ——>Convert into heat
From the above information, light of different wavelengths has different effects on photosynthesis of plants. The light required for photosynthesis of plants has a wavelength of about 400 ~ 720nm. The light of 400 ~ 520nm (blue) and 610 ~ 720nm (red) contribute the most to photosynthesis. The light of 520 ~ 610nm (green) has a very low absorption rate by plant pigments.
3. According to the above principles, the LED grow lights are made into three forms of red and blue combination, full blue, and full red to provide light with two wavelengths of red and blue, covering the wavelength range required for photosynthesis. In terms of visual effects, the red and blue LED grow lights are pink.
For white LED lights, the most common use is to use a blue core to excite yellow phosphors, thereby compounding a visual white light effect. In terms of energy distribution, there are two peaks in the blue region at 445 nm and the yellow-green region at 550 nm. The 610 ~ 720nm red light required by plants is very lacking. This explains why plants grow unfavorably under the illumination of white LEDs.
4. The chromatogram ratio of red and blue lights of LED grow lights is generally between 5:1 and 10:1, and the ratio of 7-9:1 is usually optional.
5. When LED grow lights are used to supplement light for plants, the height from the leaves is generally about 0.3-0.5 meters.
6. [Reproduced] Experts from the University of Agriculture have cultivated a batch of holly seedlings through cloning technology, and look for the most suitable "nutrient light" for plant growth according to their growth status under different color light sources. Remember to see that the holly seedlings under the purple light are the tallest, but the leaves are very small, and the roots are also poorly maintained. The seedlings under the yellowish light are not only short, but the leaves look lifeless. The holly that grows under the mixed red and blue light grows best, not only is strong, but the root system is also very developed. According to reports, the red and blue light bulbs of this light source are configured in a ratio of 9:1. In addition to holly seedlings, experts also conducted light experiments with Phalaenopsis, Oncidium, strawberries, and tomatoes. The results prove that the 9:1 red and blue light is the most beneficial to plant growth.
Since blue is good for plant leaf growth, and red is good for plant flowering and fruiting, the number of red and blue lamp beads in this lamp can be specially made according to the user's plant requirements for light.
Light and plant light affect plants in four forms: light quality, photoperiod, light intensity and light quantity. Plant growth and yield (plant size, number of flowers and other characteristics) are mainly affected by the amount of light received throughout the day The influence of plant morphology (height and plant type) is mainly related to light quality (mainly blue light, red light, etc.). For plants that are sensitive to photoperiod, their flowering (short-day and long-day plants) is mainly affected by the duration or photoperiod of light, while plants that are insensitive to photoperiod (neutral) are most affected by the amount of light. Photosynthesis is mainly affected by the amount of light and light. Strength influence. Photosynthesis mainly occurs in the visible spectrum, (400-700nm) photosynthesis is the strongest in the red light region and the blue light region. According to the growth mechanism of the photoselectivity of plant photosynthesis, the LED plant growth lamp uses LED as the light source. The RB ratio is used for color mixing, and the light necessary for plant growth is artificially synthesized. The spectrum is pure, and the spectrum is concentrated in 440-450, 650-660. Compared with ordinary LED grow lights, ordinary LED grow lights emit ultraviolet light and infrared light that are useless for plant growth, which wastes a lot of electric energy. LED plant growth lights use electroluminescence mechanism. Under the same light intensity, LED plants The growth lamp saves more than 80% of electricity than the ordinary plant growth lamp. The lifespan of ordinary LED grow lights is generally only 1000-5000 hours, while the lifespan of LE LED grow lights can reach 30,000-50000 hours, long-lasting, energy-saving, high light energy utilization, and does not produce light that is ineffective for plant growth, which is a real sense Professional lighting products that promote plant growth!
At the exhibition held in Tokyo on April 15-17, 2009, Nabeki, which is engaged in the business of electronic components, demonstrated the growth of plants receiving three different colors of LED lighting. After irradiating seedlings of the same size for 3 weeks using red LEDs with a wavelength of 630mm, blue LEDs with 430mm and a combination of red and blue LEDs in half to form pink LEDs, the growth status of each seedling was compared. The results show that pink LED lighting is most helpful to promote plant growth.
Guo Qing said that plant growth does not require all wavelengths in visible light, but only absorbs light of specific wavelengths. For example, during photosynthesis and flowering, the absorption peak of chlorophyll-red light near 660nm can promote growth. When the stamen is formed, blue light around 450nm can promote growth.
Comparing the seedlings with three different lightings, it was found that the seedlings with red LED lighting grew the slowest than the other two seedlings, and the whole was the smallest. Seedlings with blue LED lighting have fewer leaves and are elongated overall. The seedlings with pink LED lighting have larger leaves and the overall plant growth is balanced. However, different types of plants have somewhat different light wavelengths that affect their growth.
