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Drought tolerance refers to the degree to which a plant is adapted to arid or drought conditions. ''Desiccation tolerance'' is an extreme degree of drought tolerance.〔(Ars | Publication Request: Evolutionary Linkage Between Drought And Vegetative Desiccation Tolerance In Plants )〕 Plants naturally adapted to dry conditions are called ''xerophytes''. ==Adaptations to dry conditions== (詳細はC4 carbon fixation or crassulacean acid metabolism (CAM) to fix carbon during photosynthesis. Both are improvements over the more common but more basal C3 pathway in that they are more energy efficient. CAM is particularly good for arid conditions because carbon dioxide can be taken up at night, allowing the stomata to stay closed during the heat of day and thus reducing water loss.〔(Botany online: Photosynthesis - C3, C4 and CAM. Regulation of The Activity )〕 Many adaptations for dry conditions are structural, including the following: *Adaptations of the stomata to reduce water loss, such as reduced numbers or waxy surfaces. *Water storage in succulent above-ground parts or water-filled tubers. *Adaptations in the root system to increase water absorption. *Trichomes (small hairs) on the leaves to absorb atmospheric water. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Drought tolerance」の詳細全文を読む スポンサード リンク
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