The main function of the shade net is to cover the stro […]
The main function of the shade net is to cover the strong light and lower the temperature of the shed. Covering the shade net is an important measure for the greenhouse vegetable production in the hot season. However, if an inappropriate shade net is used, it will not only cause the plant to grow, but also is not conducive to flowering and fruit setting. Therefore, we must use the shade net scientifically and reasonably.
Do not judge the pros and cons of the shade net by color: the shade nets currently on the market are mainly black and silver. The black shading net has a high shading rate and a fast cooling. It should be used for short-term coverage of the fields that need fine management in the summer; the silver-gray shading net has a low shading rate and is suitable for hi-light vegetables and long-term coverage. The quality of the shading net is not determined by the color. The color of the shading net is added during the manufacturing process of the raw material.
Therefore, different vegetables should choose different shade nets. For example, tomato is a hi-light crop, as long as it meets 11 to 13 hours of sunshine, the plant will grow robust and flowering earlier. Although the effect of light on tomato is less important, light intensity is directly related to yield and quality. Insufficient light, easy to cause malnutrition, length, and reduced flowering. The light saturation point of tomato is 70,000 lux, the light compensation point is 30,000 to 35,000 lux, and the light intensity at midday is generally 90,000 to 100,000 lux. The black shading net has a high shading rate of up to 70%.
The black shading net is used, and the light intensity does not reach the normal growth demand of the tomato, which is easy to cause the tomato to grow and the photosynthetic product is insufficiently accumulated. Most of the silver-gray shade nets have a shading rate of 40% to 45%, and a light transmittance of 40,000 to 50,000 lux, which can meet the normal growth needs of tomatoes. So the tomato *** is well covered with a silver-gray shade net.