The Influence of Wind on the Behaviour of Stomata of Photosynthetic Stems of Cytisus scoparius (L.) Link

Potted transplants of Cytisus scoparius (L.) Link sub-speciesmaritimus (Rouy) Heywood (prostrate) and sub-species scoparius(erect) were subjected to an abrupt increase in wind speed.Following this change, stomata of the prostrate plants closedquite markedly to an equilibrium conductance within 60 min andremained substantially closed for at least the next 8 h. Stomatalconductance of erect plants increased slightly in the hour followingthe increase in windspeed but decreased gradually in the next8 h. These changes resulted in changes in transpiration andplant water status but stomatal responses to wind were not directresponses to changes in the bulk water status of the plants.It is suggested that the occurrence of sub-species maritimuson exposed sea cliffs and the limitation of the erect sub-speciesscoparius to relatively more sheltered habitats may be relatedto the stomatal responses to wind and the plant-water relationshipsof the two sub-species. Cytisus scoparius, broom, stomata, wind