Moderate heat pretreatment alleviates the inhibition of photosystem II activity caused by the response of cyanobacterial cells to high red light

Abstract

Pre-exposure of plants to one form of stress can impact tolerance to other forms of stress. This is called cross-tolerance. However, little is known about whether this type of cross-tolerance also occurs in cyanobacteria. Here, our results clearly indicated that short-time moderate heat pretreatment considerably alleviates the inhibitory effect of high red light but not blue light on the activity of photosystem II in the unicellular cyanobacterium, Synechocystis sp. strain PCC 6803, as determined by a chlorophyll fluorescence parameter, ΦPSII. We therefore conclude that a similar cross-tolerance strategy as identified in higher plants also occurs in cyanobacteria.