Iron heart is engaged in LED plant lighting

In 1964, the world's first red LED was successfully developed, and then the yellow LED appeared. Until 1994, the blue and green LEDs were successfully developed. However, due to the limitations of its brightness and high price, it has not been widely used as a universal light source.

With the continuous deepening of research on semiconductor luminescent materials, the continuous advancement of LED manufacturing technology and the development and application of new materials, the development of LED has made breakthrough progress, and the price has also dropped drastically. Scholars from all countries are concerned. Especially after the successful development of ultra-high brightness LED, it is widely used in the research of plant physiology or cultivation, such as photomorphogenesis, photosynthesis and chlorophyll synthesis research.

Advantages

(1) Efficient and pollution-free

The 21st century will be the century of ecological agriculture, and physical agriculture is one of the main ways to realize ecological agriculture. In many physics subject knowledge, optics plays a vital role in it. Therefore, some scholars believe that "the century of light" "coming soon. How to control different artificial light sources to implement different "light fertilizers" for green plants under the condition of insufficient sun light, not only to promote crop growth and development, but also to achieve the purpose of increasing production, high efficiency, high quality, disease resistance and pollution-free, which promotes modern agriculture in China. The development has very important practical significance.

(2) Energy conservation

LEDs are attracting the attention of the world with their inherent superiority, especially in the context of rising global energy shortages. The application of LEDs in the field of plant cultivation has many advantages: it can provide a variety of pure monochromatic light and composite spectrum, and can provide corresponding spectral combinations according to different crops and different growth and development periods; with PPFD adjustable characteristics, can simulate sunlight The change of intensity; the adjustable frequency of the illuminating frequency and the duty cycle can provide a high-frequency intermittent light-feeding mode, which is helpful for exploring the control mechanism of the bright and dark phases of photosynthesis, and can expand the energy-saving space.

Global effort

The application of LED in the field of plant physiology and plant cultivation has attracted worldwide attention.

The developed countries represented by Japan and the United States not only study the regulation mechanism of LED on plant growth and development, but also pay more attention to actively researching technologies and products that use LEDs widely in the field of plant cultivation. (1) The National Aeronautics and Space Administration of the United States conducts research on LED fill light facilities as one of the related technologies of closed life support systems such as space bases. (2) Research on the closed LED plant factory in Japan has entered the practical stage; the plant growth system produced by CCS company controls the LED lighting through the growth control software, which can realize the automatic control of different light quality; the new LED light source tissue culture container “Uni -PACK has also been successfully developed, which has the advantages of improving tissue utilization space utilization, effective wavelength utilization and lighting efficiency, and reducing the production cost of tissue culture seedlings.

The research on LED application mechanism in the field of plant cultivation in China is still in its infancy. Drawing on the results of foreign research, it is necessary to further systematically study the basic theory of LED application in the field of facility cultivation in China. It is worth noting that there are some differences in the spectral combinations, PPFD and photoperiod cycles required for different growth stages of different plants. Although some foreign literature reports the application of spectral combinations of red and blue LEDs on the growth and morphogenesis of different plants, The lack of growth characteristics of different species in different periods and the analysis of the response mechanism of plants to LED light quality regulation were not able to give the reliable parameters and system data of the best LED spectral composition, PPFD and photoperiod of different plants in different growth stages.

In addition, although China is a large country with a large plant cultivation area, the research and development of LED technology products with independent intellectual property rights in the field of facility cultivation is basically blank. It is urgent for researchers in engineering disciplines and plant disciplines to work together to develop and conform to the actual production in China. LED plant light source, automatic lighting control system, new plant growth control device and large plant factory nursery facilities. With the development of LED technology and the year-on-year decline in production costs, especially with the launch of China's semiconductor lighting project, it is believed that in the near future, various technologies and products related to LED will be widely used in the production practice of plant facilities. .