Elemental composition of groundnut leaves as affected by age and iron chlorosis

Abstract

We studied the changes with time in the composition of leaves of different age, with particular attention given to the youngest leaves, because relatively little is known of the effect of iron chlorosis on the elemental composition of groundnut leaves (Arachis hypogaea L.).

For cultivar TMV2 and a number of breeder's lines, the development of chlorosis did not cause a consistent change in nutrient content of the leaves, but marked changes in content were associated with leaf age independent of chlorosis susceptibility. Concentrations of N, P, K, Cu, Mn, and Zn in the leaves of TMV2 generally decreased with increasing age; N, Zn, and Mn concentrations decreased from the unfolded buds to the second unfolded leaf (L2), but thereafter did not decrease. The concentrations of Ca increased markedly with leaf age and Mg concentrations tended to increase.

These results indicate that while iron chlorosis did not cause any consistent changes in the elemental composition of groundnut leaves, marked changes in content were associated with leaf age.

Key words:

• Leaf age
• major and micronutrient composition