LED is one of the important factors affecting the control of plant growth by grow lights

Light environment is one of the important physical environmental factors that are indispensable for plant growth and development. Controlling plant morphogenesis through light quality regulation is an important technology in the field of facility cultivation.

LED as supplementary lighting for plant photosynthesis Traditional artificial light sources generate too much heat, such as LED supplementary lighting and hydroponic systems, air can be recycled, excess heat and water can be removed, and electricity can be efficiently Converted into effective photosynthetic radiation, and ultimately into plant matter. Studies have shown that with LED lighting, the growth rate and photosynthetic rate of lettuce are increased by more than 20%, and it is feasible to use LEDs in plant factories.

Certain wavelengths of LEDs can affect the flowering time, quality and duration of a plant’s flowering. Certain wavelengths of LEDs can increase the number of flower buds and flowering of plants; certain wavelengths of LEDs can reduce the flower formation response, regulate the length of the pedicel and the flowering period, which is conducive to the production and marketing of cut flowers. It can be seen that the flowering and subsequent growth of plants can be regulated by LED regulation.

The main purpose of the LED drive circuit is to convert the AC voltage into a DC voltage, and at the same time complete the matching with the voltage and current of the LED. As the power supply voltage of silicon integrated circuits plummets, the LED operating voltage is more and more in the optimal range of the output voltage of the power supply, and most technologies for powering low-voltage ICs are also suitable for powering LEDs, especially high-power LEDs. .

Industry Trends:
1) A series of constant voltage and constant current control electronic circuits have been developed according to the characteristics of LEDs. Using integrated circuit technology, the input current of each LED is controlled at the optimal current value, so that the LED can obtain a stable current and generate the highest output luminous flux.​​
2) The LED drive circuit has an intelligent control function, so that the load current of the LED can be controlled at a pre-designed level under the influence of various factors.
3) In terms of control circuit circuit design, centralized control, standard modularization, and system scalability are the three development directions.

According to the light requirement, it is divided into positive plants, neutral plants and negative plants.
Positive plants: Light intensity plays an important role in the growth and development of plants and the formation of morphological structures. Plants that grow and develop robustly in a strong light environment and grow poorly in shade and low light conditions are called positive plants. Common crops are also sun plants. The light saturation point (LSP) and light compensation point (LCP) of sun plants are very high, generally higher than the photosynthetically active radiation (PAR) value under natural conditions, so there is no such thing as a decrease in the net photosynthetic rate (Pn) caused by excessive light. Happening. The higher the LCP, the earlier it will enter the respiration, which is not conducive to the accumulation of organic matter, so it is not resistant to shade.
Negative Plants: Plants that grow well in low light conditions. However, it is not that the weaker the light intensity requirements of shade plants are, the better, but the light compensation point of shade plants must be reached, and the plants can grow normally.
Neutral plants: refers to plants that can form flower buds regardless of whether the sunshine time is long or short. Like peas and corn.
The second is the difference in photosynthesis. According to the way of photosynthesis, it can be divided into C3 plants, C4 plants and CAM plants. In C3 plants, CO2 fixation mainly depends on the activation state of ribulose 1,5-bisphosphate carboxylase (RuBPCase), which is the key to the photosynthetic carbon cycle. It catalyzes the carboxylation of ribulose 1,5-bisphosphate (RuBP), assimilates CO2 in the atmosphere, and produces two molecules of phosphoglycerate, which shows the importance of RuBPCase in assimilating CO2 in C3 plants. C4 plants are a high light-efficiency species evolved from C3 plants. Compared with C3 plants, it has the ability to maintain high light efficiency under high light intensity, high temperature and low CO2 concentration. The CAM mode is mainly embodied in sedum (succulent) plants, where photosynthesis occurs at night.
The third is the difference in demand. Such as greenhouse planting, plant factory, box tissue culture, balcony planting, indoor ecology, darkroom planting, etc. In this way, not only the requirements for light distribution are put forward, but also the shape of the plant lamp needs to be changed.

Post time: Aug-23-2022