Interaction between NO 3 − and abscisic acid in the regulation of lateral root elongation in Zea mays L.

Abstract

Lateral root (LR) elongation rate of 7–8-day maize seedlings depends on the availability of NO3−, NO2−, and abscisic acid (ABA) in an environment. Four-hour exposure to 0.01–1.5 mM NO2− increases the relative LR elongation rate; in the case of NO2−, the stimulation occurs only at an NO2− concentration equal to 0.01 mM. Exogenous ABA (10−6 M) inhibits the LR elongation process. In the case of a combined influence of NO3− and ABA or NO2− and ABA, the character of the response elongation reaction is different. The NO role in the regulation of LR elongation is discussed.