Light is one of the important environmental factors for plant growth, and the artificial light environment in the field of agricultural lighting has been gradually recognized, and has been widely used in leaf vegetable plant factories and fruit vegetable artificial light supplement production field, in order to achieve the purpose of improving yield and quality.
1. Choose high pressure sodium lamp or LED lamp?
As a new type of light source, LED has the characteristics of energy saving, environmental protection, long life and short response time, and has obvious advantages in the field of agricultural lighting. Compared with the traditional high pressure sodium lamp, LED can adjust the spectrum and radiation intensity according to the actual planting demand. In addition, LED is a cold light source, with a relatively low heat output, which can irradiate plants at close range without burning, and has a high light uniformity. As for the three-dimensional farm with indoor planting, the small LED size is more suitable for multi-layer planting, saving space and improving the overall planting area.
Although the LED plant growth light has its obvious advantages, the specific scheme needs to combine the species of crops and geographical location to make the final reasonable scheme. For example, in high latitude areas, greenhouse planting in winter requires a certain amount of heat energy to maintain the ambient temperature. So the mixed use of LED perpetual lamp and high-pressure sodium lamp is a good plan.
2. How to select spectrum
The light radiation related to plant growth can be divided into light synthesis with light energy function and light form formation with signal (stimulation) function. Photomorphogenesis refers to the process of plant growth, development and differentiation under light conditions. In 2017, the quantity and units of electrical radiation for plants released by the American Society of agriculture and bioengineering expanded the band of effective light for plants to 280nm-800nm. The light of different wave bands has different effects on plants. For example, increasing the proportion of blue light can promote the formation of lycopene and flavonoids in tomato fruit, and improve the quality of tomato.
It is suggested to choose the spectrum according to the species of plants, which is not only beneficial to the growth and overall quality of plants. However, in practical operation, it is not easy to find and determine the spectrum. In addition to the need for many experiments, there are many factors affecting the spectrum. Therefore, it is recommended to have more powerful manufacturers of plant growth light supplement lamps, who usually have certain experience and data accumulation.
3. Uniformity of light
In addition to the type and spectrum of the light supplement lamp for plant growth, there are also many key parameters, such as the uniformity of light. The uniformity of light (regional uniformity, inter plant uniformity and crown uniformity) determines the consistency of plant appearance characteristics and individual plant products. For the plant of artificial light environment, high yield and high quality is its core goal, so it is necessary to ensure the uniform distribution of light intensity and light quality in the process of light environment design to ensure the uniformity of plant.
