Regulation of the Calvin cycle under abiotic stresses: an overview

Anthropogenic activities are creating various ecological problems, thus emerging diversity of abiotic stresses like water, salinity, temperature, cold, heavy metal, ozone, and UV radiation. Significant loss in plant growth rate and yield due to these stresses has imparted a major challenge to the food security globally. Response to such abiotic stresses has been studied well from the physiological level to the molecular level. Photosynthesis and carbon fixation is pivotal for all the plants that are affected by mostly all abiotic stresses. The downregulation of Calvin–Benson–Bassham cycle is also augmented by stomatal closure, CO2 diffusion through stomata, decreased activity of ribulose bisphosphate carboxylase/oxygenase activity, which in turn decreases the CO2 assimilation, consequently resulted in reduced biomass accumulation and crop yield. Other response includes the synthesis of stress hormones such as abscisic acid, regulating factor for stomatal opening, and generation of reactive oxygen species causing oxidative stress. There is a complex network of interaction and regulation that acts during stress situation and helps plant to adapt accordingly. This chapter focuses on the damaging effect of various abiotic stresses on Calvin–Benson–Bassham cycle and provides updated information on the cycle and the factors associated with its regulation.