Effect of soil arsenic on yield and as and P distribution pattern among plant organs of buckwheat and castor oil plant

A green house experiment was conducted to investigate the effect of different soil As concentrations (0, 50 and 100 mu g g(-1)) on plant yield and As and P distribution pattern among different parts of buckwheat (Fagopyrum esculentum L.) and castor oil plant (Ricinus communis L.). In case of buckwheat, root As, leaf As, flower As and seed As showed significant relationship with allotted soil As concentration for each plant. On the contrary, though castor oil plant's root and leaf As showed significant relationship with soil As concentration but leaf As accumulation was much more lower than buckwheat. For the better understanding of As and P distribution pattern among the plant organs of the two plant species; we also measured the As and P concentration for each plant organs and P/As ratio of different plant parts. Compared to buckwheat, castor oil plant was able to tolerate high concentration of As in its system by effectively maintaining greater ratio of P/As in the leafs.