Morphophysiological aspects of radish plants under exogenous alanine application

ABSTRACT Radish is a fast-growing vegetable of great economic importance, particularly for small-scale farmers. Amino acids, such as alanine, supplied by exogenous application, can act as a biostimulant by participating in physiological processes linked to nitrogen metabolism and protein synthesis, promoting plant growth. Therefore, this study aimed to evaluate the effects of exogenous alanine application on the morphophysiological aspects of the 'Crimson Giant' radish variety. The experiment was conducted in a greenhouse at the Federal Rural University of the Semi-Arid Region, Mossoró, RN, Brazil. A completely randomized design comprised seven alanine concentrations (0.0, 2.5, 5.0, 7.5, 10.0, 12.5, and 15.0 mM) with five replicates. The variables evaluated were: plant height, stem diameter, number of leaves, leaf area, leaf dry mass, specific leaf area, and leaf mass per unit area. For the roots, the following variables were assessed: fresh mass, length, diameter, pH, soluble solids, and firmness. It was found that the exogenous application of alanine altered the morphophysiological characteristics of radish plants, with the 5.0 mM concentration standing out. Increasing alanine concentrations reduced soluble solids and root firmness. Exogenous application of alanine, particularly at a concentration of 5.0 mM, increased stem diameter, root diameter, and leaf area, highlighting its potential role as a biostimulant in radish cultivation.