Water salinity and salicylic acid in guava cultivation

The objective of this work was to evaluate the growth, physiology, production and postharvest quality of guava cv. Paluma under salt stress and foliar application of salicylic acid. The experiment was conducted under greenhouse conditions, in a 2 × 4 factorial design, with two levels of electrical conductivity of irrigation water (0.6 and 3.2 dS m-1) and four concentrations of salicylic acid (0; 1.2; 2.4 and 3.6 mM), with three repetitions. Irrigation with 3.2 dS m-1 water promoted reductions in gas exchange, chlorophyll a and b contents, relative water content, and increased electrolyte leakage in the leaf lamina of guava plants at 150 days after transplanting. Water with an electrical conductivity of 3.2 dS m-1 reduced rootstock and scion diameter, crown diameter, crown volume, and vegetative vigor index, as well as gas exchange and production components. The application of salicylic acid at concentrations ranging from 0 to 3.6 mM did not mitigate the effects of salt stress on Paluma guava plants at 390 days after transplanting.