石仙桃（兰科）中的 CAM 空息。

CAM-idling in Hoya carnosa (Asclepiadaceae).

机构信息

Department of Botany and Plant Sciences, University of California, 92521, Riverside, CA, USA.

出版信息

Photosynth Res. 1983 Jan;4(1):203-11. doi: 10.1007/BF00041816.

Abstract

In the leaf sueculent Asclepial Hoya carnosa (L.) R. Br., CAM photosynthesis occurred under well-watered conditions, as characterized by diurnal gas exchange and changes in titratable acidity. Following 10-12 days of severe water stress, the plants shifted from CAM to a modified CAM-idling mode of metabolism. CAM-idling was characterized by complete or almost complete stomatal closure accompanied by CAM-like diurnal changes in titratable acidity. H. carnosa plants maintained this CAM-idling mode of photosynthesis for at least 8 weeks. Upon reirrigation, the plants returned to the original CAM mode within 1 week. These results suggested that CAM-idling is a reversible, intermediate form of sustained metabolism which enables plant survival under conditions of extended drought.

摘要

在肉质多浆的叶子植物球兰（Hoya carnosa）中，CAM 光合作用在水分充足的条件下发生，其特征是昼夜气体交换和可滴定酸度的变化。在经历 10-12 天的严重水分胁迫后，植物从 CAM 转变为一种改良的 CAM-休眠代谢模式。CAM-休眠的特征是完全或几乎完全关闭气孔，同时伴随着可滴定酸度的 CAM 样昼夜变化。球兰植物至少维持这种 CAM-休眠光合作用模式 8 周。重新浇水后，植物在 1 周内恢复到原始的 CAM 模式。这些结果表明，CAM-休眠是一种可持续代谢的可逆中间形式，使植物能够在延长干旱条件下生存。