Individual pigments were identified by their
characteristic absorption bands and their concentrations were calculated using appropriate equations (Parsons &
Strickland, 1965). Individual pigments were resolved by thin layer chromatography and the spots were identified
by their characteristic colours with staining reagents and by their RF values (Stahl, 1967). The activities of
photosystems I1 and I, and NADP-photoreduction, were measured as described by Codd & Sallal (1978).