11. Accumulation of these hormones appears to cause increased stomatal density such as when the plants are kept in closed environments. 12. The upper surface of the leaves is green and shiny, while the undersides have 2 wide silvery stomatal bands. 13. The leaves are linear, long and wide, glossy green above, and with two white stomatal bands below. 14. He demonstrated the link between forests and the atmosphere using novel techniques for measuring leaf water potential and stomatal conductance. 15. The leaves have two whitish lines on the bottom, each of which is formed by wax-covered stomatal bands. 16. The stomata are usually restricted to the abaxial or underside of the leaf, forming two stomatal bands around the midrib. 17. Potassium channels and pumps have been identified and shown to function in the uptake of ions and opening of stomatal apertures. 18. It is thought that plant hormones, such as ethylene and cytokines, control the stomatal developmental response to the environmental conditions. 19. The stomatal armature contains one dorsal tooth and two subventral teeth, while the wall may additionally contain rows of small denticles. 20. The needles are 1 2.8 cm long, pruinose, with stoma-lines above and 2 stomatal bands below.
