Formation of aerenchyma in roots of Zea mays in aerated solutions, and its relation to nutrient supply

Abstract

AbstractThe formation of lysigenous cavities (aerenchyma) in the root cortex of maize, Zea mays L. cv. Capella, under well‐aerated conditions has been studied in relation to the composition of the nutrient solutions. Nitrogen, either supplied as nitrate or as ammonium, reduced the cavity formation by the roots. This reduction was most apparent at nitrate concentrations above 2 mM. Cavities were increasingly formed when the nitrate concentration was decreased and they reached their largest dimensions in roots growing in water. Thus, inadequate availability of nitrogen leads, under acrated conditions, to deterioration of cortex cells and cavity formation in the maize roots. It is suggested that cavity formation in these roots is connected with reduced nitrogen assimilation.