Effects of Casuarina equisetifolia leachates on photosynthesis of Vatica mangachapoi Blanco seedlings

The effects of Casuarina equisetifolia allelochemicals on the photosynthesis parameters of V. mangachapoi seedlings were studied to explore the possibility of developing mixed forest of C. equisetifolia and Vatica mangachapoi. The C. equisetifolia leachates markedly reduced the net photosynthetic rate, stomatal conductance, respiration rate, light compensation point, maximal RuBP regeneration rate, apparent quantum efficiency, carboxylation efficiency, but there were no effects of 0.125 g/ml and 0.25 g/ml concentrations. However with increase in leachates concentration, the CO2 saturation point, CO2 compensation point of V. mangachapoi seedlings were increased. These results suggested that reduction in stomatal conductance under the influence of allelochemicals is not the primary limiting factor of photosynthesis, but allelochemicals also affect the RuBPCase activity which reduces the photosynthesis in V. mangachapoi seedlings.