A New Theory of the Mechanism of Stomatal Movement

SUMMARY After a brief examination of the classical theories of stomatal movement and their drawbacks, a new theory is propounded. It postulates (a) that the important movement is that of closure-, (b) that this is an 'active' process; and (c) that the ubiquitous carbohydrate changes are secondary, 'stabilizing' changes, probably not directly linked to the main process. The evidence for the theory is stated and discussed, and some implications examined.