Damage of photosynthetic apparatus in the senescing basal leaf of Arabidopsis thaliana: A plausible mechanism of inactivation of reaction center II

► A plausible mechanism for inactivation of RC II discussed. ► Increase in redox state of QA− could be central to the inactivation of RC II. ► Increase in 1-qP indicate blockage of electron transport from QA to QB. ► Redox state of QA− & possible blockage between QA and QB are supported by TL. ► The decline in peak height & down shift of B and Q bands support damage of RC II.