Home > News > Content

Plant Light Physiology And Led In Plant Illumination Advantage

Aug 29, 2017

The idea of "the people taking food as the day" has a long history and the importance of food to the survival and development of mankind is a universal concept. With the continuous growth of the global population, in the limited arable area, human use of science and technology to develop a variety of agricultural and farming technology, to find ways to solve the problem of food supply, and "plant plants" is the hot topic in recent years, it has solved the climate, geography, space ... and other factors, to provide people with a source of plant food, and the stability and quality of the characteristics of the more can be "food to Ann First", the food and safety of each person's health and life, can protect food security, let people eat health, safety, for the common people is "big thing."

Several elements of plant growth: sunlight, water, air and temperature, and plants are transformed by photosynthesis into chemical energy needed for growth and development, which drives the growth and development of tissues in various parts of plants, and these growth factors are important parameters in plant plants.

Plant light physiology and led in plant illumination advantage 

Plant Light Physiology

In this paper, the perspective of plant light physiology, for the artificial light source part, to explore the application of LED in the niche.

The so-called light quality and light quantity of the plant illumination refers to the color of light (wavelength), intensity of irradiation, the period of light and the cumulative total amount of light, different pigment molecules in plants absorb different wavelengths, such as the well-known chlorophyll-absorbing photons for photosynthesis, forming ATP and NADPH chemical energy, and other photosensitive elements (phytochrome) affected by red light and far red light, the blue pigment (cyrptochrome) and Shangkunsu ( Phototropin) ... And so on, regulating the germination, growth and differentiation of plant seeds, the movement and development of chlorophyll, stomatal opening and closing, flowering induction, pigment synthesis, enzyme activation, protein synthesis ... and other physiological phenomena.

Plant light physiology and led in plant illumination advantage  

Source: Sullivan and Deng ($number) Developmental Biology 260:289-297.

Plant after hundreds of millions of years of evolution, the development of a variety of species, for the light characteristics of the main growth day plant (Long-day plant), Short day plant (Short-day plant), Japan-China plant (day-neutral plant) three species, in addition, there are double day type, long and short day type, the long-term. The following diagram explains the effect of photoperiod on flowering, and it is known that the critical dark period is more important than the critical day length, that is, the long night flowering is determined by the dark period, and the length of time is not light. 

In addition to the effects of photoperiod, the above diagram also illustrates the effects of different wavelengths, either inhibiting Part flowering or promoting Part flowering, which can be treated with 660nm red light (R). If the red light is treated with 730nm far red (FR) irradiation, the red night interruption is offset by far red light, and the Photosensitizer is also involved in the induction of flowering plants.

Another optical cycle concept is the daily total amount of light (DLI, daily Light Integral), is to light intensity multiplied by time, get daily cumulative total amount of light, as people eat three meals a day, the light needs to be evenly distributed and not too concentrated, the total amount of light control over and below will have adverse effects on plant growth and development.

-DLI Unit: mol/m2

-DLI=PPFD x Time (SEC) 

Plant plants must optimize the distribution of the light source according to the following usage conditions to obtain the best growth curve:

-Different growth stages: seed germination/nursery/vegetative growth/reproductive physiology ... Stage

-Different purposes: accelerated growth/flowering regulation ...

-Different functions: promote metabolic production/strengthen the downstream response of special genes ...

Led in the advantages of planting

Plant plants in accordance with the way the light source, can be divided into:

Sun light and type (artificial fill)

All artificial light source type.

The traditional artificial light intensity control, usually using the number of lamps and the distance to do the adjustment, and high pressure sodium lamp to produce heat, can not close the radiation, the common traditional light source wavelength distribution can not make any changes. LED is a directional light source, the principle of luminescence is cold, the volume of a small number of wavelengths placed in the same lamp, you can use the current size of the adjustment intensity, or even the use of pulse (pulse) mode control, coupled with high led efficiency (power saving), monochrome wavelength and color complete ... And so on, according to the different plant species, purposes and needs, the design of various types of light source, accurate control of the required light quality/light quantity, it is applicable to a variety of irradiation and type of plant plants, these are traditional light source can not do.

Crystal Photoelectric LED product wavelength distribution map

Plant light physiology and led in plant illumination advantage 

Plant light physiology and led in plant illumination advantage 

According to the needs of the plant light source, the use of different wavelengths of LED, based on each led output power, lamp efficiency, light angle and irradiation distance/area, to find relevant parameters, so that the best efficiency/demand for the design of LED plant lighting light source.

-Photon calculation of LEDs at different wavelengths: ppf=[λ (NM) x power (MW)] 119500μmol/s

Plant light physiology and led in plant illumination advantage 

With the rapid development of LED, through the continuous development of epitaxial and chip technology, luminous efficiency of the steady improvement of the year, in the application of the LED chip is a major breakthrough, especially 660nm and 730nm products.

Plant light physiology and led in plant illumination advantage 

The following figure is the Crystal Yuan photoelectric plant application led development process (660/730nm), luminous efficiency with steady amplitude each year continuously progress, 660nm high-power products have reached more than 60%, 730nm also reach 50%, 2018 years to continue toward a higher goal ahead, leading the industry. Plant plants are compared to traditional agriculture, need higher energy consumption, higher light efficiency means less electricity costs, electricity tariffs are long-term fixed operating costs, the use of LED in addition to effectively reduce the cost of lighting (costs), long life also reduce the maintenance cycle problem, LED has become the best source of plant lighting.

Plant light physiology and led in plant illumination advantage 

Crystal Yuan photoelectric for the industry's leading brand, stable quality and technology, coupled with patent protection, has been the international brand manufacturers designated use and long-term cooperation. The progress of science and technology brings people a better quality of life, plant lighting applications In addition to industrial research and development, but also need more input and research of agricultural professionals, to enhance the relevant professional knowledge and technology, the booming plant lighting industry and market, to achieve a mutually beneficial goal.