The Plants on Earth has been hundreds of millions years to adapt the solar spectrum light quality completely- Each plant absorption in different spectral and light quality range under the full spectrum of sunlight irradiation. This is like the different plants to various minerals, the demanded in gas fertilizer is also different, too. Nitrogen, phosphate and potassium is main element – With three main elements but without other trace elements, it can not grow so well. The large number of elements and trace elements are essential fertilizer to the plants.
In the full spectrum of visible light from the sun, the blue light , green light and red light region of ppfd is equivalent to mineral . Three major elements of gas fertilize ; N, P ,K and K and the uv light , violet light, near red light, and far-red light is the trace elements — That is the new concept of light fertilizer (light fertilization concept)
The plants should adjust the ratio of three main elements in N, N P, K P to the visible light region of blue, green and red light of ppfd, and adjust more suitable ratio for plant photosynthesis in blue, green, red light of the ypfd , too.
As shown in the graphic, it can be adjusted the ratio of blue, green and red light to a more consistent quality light for plant photosynthesis. It will be able to reduce the amount of light into the greenhouse and reduces the temperature;
Also it reduces the heat and humidity produced by transpiration of plants — which reduces the temperature and humidity in the greenhouse, and improve the micro-climatic conditions inside the greenhouse.
Thus, there is the theory of reducing the resistance —
1.The transpiration of plants just as human perspiration — exhaustion and electrolyte … etc.
2.Plants receiving too much sun light and in order to resist the sun to avoid sunburn — it’s consume antioxidants; consumption of antioxidant vitamin C and other substances
3.Plant in order to resist excess sunlight (over the light saturation point), the photosynthesis of plants will weaken or even stop.
4.Plants will also increase the respiration during the high temperature in the greenhouse — exhaustion
5.Greenhouse humidity is too high are lead to disease
Conclusion: Adjustable shade net and plastic film could adjust the sun light spectrum and meet the demand for greenhouse or protected culture
1.light fertilization
2.Reducing the resistance
3.Increase the number of diffuse light (Transmission of 80% Knitted Shade net- Blue light 53%~63%, Green light 41%~47% , Red light 67%~78%=54%~63% (400nm~700nm) about 20% directly light and 34%~43% diffuse light—80% of Knitted Shade net about 20% directly light – Blue light 20% , Green light 20% and Red light 20%
