Effects of simulated acid rain and exogenous Al on assimilation and accumulation of Al and some nutrition elements of tea plants.

In order to provide valuable information to manage tea garden in acid deposition region,southern China,the assimilation and accu-mulation of Al and some nutritional elements in tea plant were studied using pot experiment treated with different pH acid rain(3.0,4.5,6.0) and exogenous Al(0,0.5,1.0 g.kg-1).The results showed that the content of aluminum in roots,shoots and leaves of tea plant increased with increasing dosages of Al treatment.Simulated acid rain increased Al accumulation in roots,shoots and leaves of tea plant under suitable Al treatmen(t0.5 g.kg-1 soil),while the simulated acid rain at high acidity(pH3.0)and the aluminum at high dosages(1.0 g.kg-1 soil)inhibited Al accumulation in tea plant.Exogenous Al promoted P,Cu and Fe accumulation in roots,shoots and leaves of tea plant and K accumulation in shoots and leaves,while had no obvious effects on K in roots of tea plant.Exogenous Al inhibited Ca,Mg and Zn accumulation in roots of tea plant,and had no obvious effects on their translocation in tea plant,thus these elements increased in the shoots and leaves of tea plant.Simulated acid rain had no apparent effects on P in roots and shoots,while simulated acid rain at pH4.5 increased P accumulation in tea leaves.Simulated acid rain had no apparent effects on K,Ca,Mg,Cu and Zn content in tea plant.Simulated acid rain decreased Fe accumula-tion in roots of tea plant,but had no obvious effects on shoots and leaves of tea plant without exogenous Al treatment.Under exogenous Al treatment,simulated acid rain obviously decreased Fe content in roots,shoots and leaves and the higher treatment dosages of exogenous Al,the lower content of Fe in roots,shoots and leaves.