Growth and gas exchange of West Indian cherry irrigated with saline waters under combinations of nitrogen-potassium fertilization

Abstract

Fertilization management has been one of the techniques used to mitigate salt stress in crops. In this context, this research aimed to study the effect of different combinations of nitrogen and potassium fertilization on growth and gas exchange of the West Indian cherry crop irrigated with salinized water at different vegetative stages. The experiment was conducted in field, in a randomized block design, with treatments arranged in a 5 x 4 factorial scheme, referring to five irrigation water salinities (ECw): 0.3, 1.3, 2.3, 3.3 and 4.3 dS m-1 and four combinations of nitrogen and potassium doses: C1 = 70% + 50%; C2 = 100% + 75%; C3 = 130% + 100% and C4 = 160% + 125% of N and K2O, respectively, of the recommended dose for West Indian cherry, with three replicates and one plant per plot, consisting of a 60 L pot. Harmful effects of water salinity manifested at 230 days after transplantation (DAT) on the stem and primary shoot diameter, from ECw of 2.32 dS m-1 on, and the tested fertilizer combinations did not mitigate them. Fertilization with 70% N + 50% K2O favored gas exchange activity and higher plant growth from 170 DAT, regardless of water salinity.