Potassium and calcium distribution patterns along the leaf insertion gradient of bean plants grown in nutrient solutions

Abstract

Potassium and calcium distribution patterns along the leaf insertion gradient of bean plants (Phaseolus vulgaris L. cv Tacarigua) were analyzed in plants grown in different K and Ca concentrations in the nutrient solution. The plants were sampled at the early flowering stage and the leaves analyzed following the helix or genetic spiral which follows leaves in the order of their origin at the shoot tip. Different canopy profiles for K and Ca showed that “critical concentration limits”; could be established for K but not for Ca, due perhaps to the non‐phloem mobile nature of this element. Besides, sampling procedures based on a “representative”; leaf (or leaves) were compared to those based on the sampling of the whole canopy in order to obtain reference nutrient concentration values.

Key words:

• plant analysis
• leaf insertion gradient
• Phaseolus vulgaris, L.