Department of Biology and the Philip L. Boyd Deep Canyon Desert Research Center, University of California, Riverside, California 92502.
Plant Physiol. 1973 Dec;52(6):539-41. doi: 10.1104/pp.52.6.539.
Contrasting metabolic regimes operate in Opuntia basilaris Engelm. and Bigelov, before and after precipitation. During periods of drought, atmospheric CO(2) exchange and transpiration are greatly reduced throughout the day/night cycle by stomatal closure and a highly impervious cuticle. The hypothesis is that endogenously produced CO(2) is retained and recycled through dark CO(2) fixation, organic acid transformations, photosynthesis, and respiration. Immediately following precipitation, nighttime stomatal opening is initiated, permitting increased atmospheric CO(2) assimilation and organic acid synthesis.
在降雨前后,恩格勒氏仙人球和大花仙人球的代谢模式截然不同。在干旱时期,通过关闭气孔和形成高度不透水的角质层,全天/夜间的大气 CO(2) 交换和蒸腾作用大大减少。假设是内生产生的 CO(2) 通过暗 CO(2) 固定、有机酸转化、光合作用和呼吸作用被保留和再循环。降雨后立即开始夜间气孔开放,允许增加大气 CO(2) 同化和有机酸合成。