The Effect of Chilling Maize Shoots and Roots on the Electric Potential, Composition of Fatty Acids and the ATPase Activity in the Non‐chilled Organs of Seedlings

The effect of separate chilling (5°C for 2 and 4 days) on the shoots and roots of two maize hybrid seedlings on the electric potential, the composition of fatty acids and the ATPase activity in the microsomes of non‐chilled leaves and roots (20°C) was investigated. It has been found that the low temperatures induced on the non‐chilled organs gave similar changes to organs exposed to a reduced temperature. The changes consisted of a parallel depolarization of leaf and root membranes and similarly a decrease in the ATPase activity as well as changes in the unsaturation of the membranes’ fatty acids. The reduction of the acid content 18:2 was particularly significant, which in the leaf microsomes correlated with a drop in the ATPase activity. The similarity between the reactions of the chilled and non‐chilled parts of the plant gives evidence of a communication’ between the organs which may facilitate a coordinated reaction of the entire organism to stress. The background for these phenomena could be die action potential of die chilled parts of seedlings which, in the non‐chilled parts, might produce changes in the structure of biomembranes and in the activity of enzymes.