Crescimento de Erythrina velutina willd. submetida a estresse salino e aplicação de ácido salicílico

Abstract

Erythrina velutina is an endemic species of the Northeast region of Brazil, known for displaying pharmacological properties and potential timber. However, its growth may be compromised by abiotic factors such as water scarcity and excess salts. The use of growth regulators such as salicylic acid is among the methods used to mitigate the negative effects of stress on vegetables. The objective of this study was to evaluate the growth of Erythrina velutina seedlings submitted to saline stress and salicylic acid application. The experimental design was a randomized complete block design with a 5 x 5 incomplete factorial scheme, generated from the Central Composite Box matrix with five levels of electrical conductivity of the irrigation water (ECw = 0.5, 1.74, 4.75, 7,76 and 9.0 dS m-1) four doses of salicylic acid (SA = 0.0, 0.29, 1.0, 1.71 and 2.0 mM L-1), with four replicates. The following variables were evaluated: plant height, leaf number, stem diameter, relative and absolute growth rate of height and stem diameter, root dry matter, stem, shoot and total leaf weight and Dickson quality index. Data were submitted to analysis of variance by the F test, in cases of significance was performed polynomial regression analysis. The salinity promotes serious damage to the growth of Erythrina velutina plants, being more pronounced in increasing levels of electrical conductivity. The application of salicylic acid at the concentrations used does not attenuate the effects of salinity.