Effects of long term exposure to aluminium stress on the accumulation and distribution of K+, Na+, Ca2+, Mg2+, Fe2+ and cl- in rice and chickpea plants

Abstract

Sand culture experiments were undertaken to examine the effect of increasing aluminium levels (50-150 µM) on the mineral nutrients uptake (K⁺, Na⁺, Ca²⁺, Mg²⁺, Fe²⁺ and Cl^-). Increasing concentrations of Al inhibited the uptake of K⁺, Ca²⁺, Mg²⁺ and Fe²⁺ but enhanced that of Na⁺ and Cl^- in the root and shoot of rice, and the root, stem and leaves of chickpea. 150 µM Al caused a maximum inhibition of K⁺ accumulation in the root and shoot of rice ranging from 25.5 to 49.0%  and 33 to 55.5%, respectively, from 7 to 28 day of treatment. In the root, stem and leaves of chickpea, 150 µM Al inhibited K⁺ content by 23.9 to 84.0%, 13.2 to 54.4% and 25.3 to 61.2%, respectively, from 7 to 28 day of application. On the contrary, a dramatic 2.7 to 3.1-folds and 70.8% to 2.3-folds stimulation of Na⁺ accumulation was recorded in the root of rice and chickpea, respectively, following 100 µM Al treatment from 7 to 28 day of treatment. Different concentrations of aluminium led to a stimulation of Cl^- accumulation in different parts of rice and chickpea plants. In rice and chickpea plants, the inhibitory effect of aluminium stress on the accumulation of Ca²⁺,Mg²⁺ and Fe²⁺ was enhanced with the increase in Al concentration from 50 to 150 µM.