Studies in Stomatal Behaviour

Publisher Website
Google Scholar
Abstract
If Pelargonium stomata, wide open under a porometer-cup, are subjected to a mechanical shock and then darkened, subsequent closure is markedly accelerated. The effect persists for at least 18 hours and, provided a relatively lengthy dark period quickly follows the shock, is unaffected by subsequent light periods. If, however, the shock is followed by a light period of about 2 hours, subsequent closure is decelerated, and this deceleration similarly persists through subsequent dark periods. The effects can largely be explained on the basis of shock-induced respiratory changes, if it is postulated that photosynthesis inhibits respiration in chlorophyllous tissue. The effect of the shock is not instantaneous, the new pattern of behaviour not being discernible in either case until the stimulated tissue has been exposed to light or darkness for perhaps an hour. It appears that in occasional sensitive leaves such phenomena may be induced by the slight shock involved in fitting a porometer-cup, and the conditions of light or darkness to which the cup is subjected immediately after fixing may then influence its subsequent behaviour.

This publication has 0 references indexed in Scilit: