Mesophytes are terrestrial plants which are adapted to neither a particularly dry nor particularly wet environment.
Properties
Plants that have an adequate water supply. Such plants have some xeromorphic features in order that they should conserve enough
water such as a
cuticle,
stomata with regulable diameter, and a greater number of stomata on the undersides of leaves, but lack others, meaning they do not retain too much water. Because of their lack of particular adaptation, when they are exposed to extreme conditions they do not survive well. For example, in hot weather they may overheat and suffer from
temperature stress. They have no specific adaptations to overcome this, but, if there is enough water in the soil to allow this, they can increase their rate of
transpiration by opening their stomata, thus meaning some
heat is remobed by the exiting water. In dry weather they may suffer from water stress (losing more water via transpiration than can be gained from the soil). Again they have no specific adaptations to overcome this, and can only respond by closing their stomata to prevent further dehydration. Their cells are thus likely to lose turgidity. This may cause the plants cells to become plasmolysed. prompting
wilting. Wilting does actually have some benefits as it reduces the leaf surface area exposed to the
atmosphere, meaning it reduces transpiration, and that exposed to solar radiation, meaning temperature stress is reduced. Although mesophytes often recover from such wilting, prolonged periods of it can lead to permanent wilting or cell
plasmolysis and subsequently
death.
Plant morphology |
Botany