Photosynthetic O(2)-production and photorespiratory O(2)-uptake were measured, using stable isotope techniques, in isolated intact leaf cells of the C(3) plant Xanthium strumarium L., and isolated intact chloroplasts of Spinacia oleracea L (var. Yates 102). Considerable light dependent O(2)-uptake was observed in both systems, a proportion of which could be suppressed by CO(2) (63% suppression ...

recently, 6-(2-naphthyl)-2, 3-dihydro-as-triazine-3-thione (ndtt) was synthesized in laboratory and used successfully for the spectrophotometric determination of nanogram levels of cu2+ in aqueous solution. this reagent forms a specific red complex with cu2+ ions after the extraction by chloroform at alkaline ph. the absorption of the complex in the uv region (313 nm) is about 8 times as strong...

Limited magnesium (Mg) supply adversely affects photosynthesis. This is particularly related to the high demand for Mg of key enzymes in chloroplast, such as photosystems, ATP synthase and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). The accepted critical concentrations yield dry matter (DM) are 1.5–3.5 mg g?1 DM. Earlier studies on deficiency indicated that carbon fixation by Rub...