(1) Light intensity
① The influence of light intensity on pewter plant. The growth rate of ash plants is closely related to the intensity of their photosynthesis. The intensity of photosynthesis is largely affected by the intensity of light. Under conditions where other ecological factors are suitable, when the energy substances synthesized by photosynthesis can just compensate for the consumption of respiration, the light intensity at this time is called It is the light compensation point. Below the light compensation point, the white wax plant will stop growing. For example, ash plant under the canopy of ash plant, sometimes the leaves and twigs wither because of insufficient light. When the light intensity exceeds the compensation point and continues to increase, the intensity of photosynthesis will increase proportionally, and the growth of white wax plants will also accelerate, that is, grow taller and thicker. But when the light intensity increases to a certain level, the increase in photosynthesis intensity will gradually slow down. When it finally reaches a certain limit, the intensity of photosynthesis will no longer increase with the increase in light intensity. Saturation point, that is, the light intensity at which the accumulated material of photosynthesis reaches its maximum. The growth of ash plant generally requires 18,000 to 20,000 lx of light intensity. According to different garden white wax plants have different responses to light intensity, they can be divided into three categories.
The growth rate of ash plant is closely related to the intensity of photosynthesis
a. Positive white wax plant. Such white wax plants need to be able to grow normally under strong light.
Most of the one or two-year-old white wax, perennial white wax, and pulpy white wax plants on the open ground, such as larch, masson pine, Ailanthus altissima and other trees belong to this kind of white wax plants.
b. Negative white wax plant. This type of ash plant cannot tolerate strong direct light, and needs to be able to grow well under moderate shade, such as fern ash plant, orchidaceae, bromeliaceae, ginger family, Gesneriaceae, Araceae and Begonia ash plant; and Trees such as spruce, fir, and yew are all ash-negative plants. There are also some vegetable white wax plants such as spinach, lettuce, chrysanthemum, etc. that can grow well under sufficient light, but under weaker light, they grow fast and have soft quality. Use this feature in production, often reasonable close planting or appropriate intercropping to increase yield and improve quality.
c. Neutral white wax plant. The requirement of light intensity for this type of white wax plant is between the positive and negative white wax plant, or it is not very sensitive to the length of sunshine. Usually like to have enough sunlight, but it can grow normally in the shade. For example, Hemerocallis, Platycodon grandiflorum and so on.
② The relationship between light intensity and leaf color. In foliar ash, some ash leaves often show multiple colors such as yellow, orange, and red, and some even show excellent patches. This is because the elements contained in the chloroplast are different and under different lighting conditions. The effect produced under the conditions. For example, the leaves of red mulberry, red maple, and Nantian bamboo synthesize more lutein when under strong light, but synthesize more carotene under weak light.