Stomatal Behaviour and Environment

Abstract

Stomata1 movement is a manifestation of strain in the epidermis, associated with change in the hydraulic pressure in the epidermal cells. This chapter discusses the role and behavior of stomata in the hydrology of the soil–plant–atmosphere system. Stomata operate in the light in such a way as to maintain positive turgor in the leaves, in the majority of crop plants and other species. The transient response of stomata to changes in environment which cause rapid changes in plant–water relations is quite dramatic. The nature of the stomatal response to change in water potential must involve the mechanical and hydraulic attributes of the stomatal apparatus. There is only a tenuous relationship between the potential of water in leaf tissue in bulk and the local potential of water to which an individual stoma responds in ways, which are also discussed. Thus the transient response of stomata to change in rate of evaporation may be a device which is designed to enhance the speed of the response to light. © 1977 Academic Press Inc. (London) Ltd.