What is the significance of transpiration to plants?

Plant transpiration Stomatal transpiration is significantly regulated by light, temperature, CO 2 and other factors.

(1) nudity is an important regulation of stomatal movement. There are two kinds of direct action, one is indirect action, and the light signal felt by the other photoreceptor occurs through photosynthesis. The transpiration of light causes the influence of stomatal opening, reduces internal resistance, and thus increases transpiration. Secondly, light can improve the temperature of the atmosphere and leaves, increase the water vapor pressure inside and outside the leaves and accelerate the transpiration rate.

(2) The physiological process of enzyme reaction is related to temperature stomatal movement, so transpiration rate has great influence on temperature. When the temperature is too high, the ratio of leaf temperature Temp 2 is as high as 10℃, so the increase of steam pressure in stomata cavity is greater than that of air steam pressure, which increases the internal and external pressure of leaf steam and strengthens transpiration. When the temperature is too high, the leaves lose too much water, the stomata are closed and transpiration is weakened.

(3)CO2 has great influence on stomatal movement. Low concentration of CO2 promotes stomatal opening, while high concentration of CO2 makes stomatal close quickly (whether bright or dark). At high concentration of CO2, stomatal closure may be due to (1) high concentration of CO2 increasing the permeability of cell membrane, leading to K+ leakage and eliminating solute potential gradient inside and outside plasma membrane. ② Intracellular CO2 acidification affects transmembrane proton concentration.