# Salicylic Acid Reduces Salinity Stress in Barbados Cherry Irrigated with Oilfield Water in Semiarid Brazil

## TL;DR

Salicylic acid helps reduce the harmful effects of salty irrigation water on Barbados cherry plants in dry regions of Brazil.

## Contribution

Combining oilfield water with salicylic acid improves plant growth under salinity stress in semiarid areas.

## Key findings

- Salicylic acid at 1.3 mM reduced salinity stress effects up to 2.63 dS m–1.
- OPW-D3 (50% SW + 50% OPW) was most effective for seedling morphophysiology.
- Junco genotype showed best seedling quality, while Crioula tolerated more salinity.

## Abstract

The Barbados cherry (Malpighia emarginata DC) is a fruit crop of significant economic, social, and nutritional
importance, particularly in Northeast Brazil. Its sustainable cultivation
in semiarid regions depends on irrigation due to the negative water
balance during most months. Given water scarcity, strategies such
as using lower-quality water, including brackish water, wastewater,
and oilfield produced water (OPW), have been investigated. These water
sources, combined with proper irrigation management and salicylic
acid (SA), can mitigate abiotic stresses like salinity. This study
evaluated Barbados cherry rootstock production under irrigation with
synthetic OPW and SA concentrations at the Federal Rural University
of the Semi-Arid Region, CaraúbasRN, Brazil. A randomized
block design with a 5 × 4 × 2 factorial arrangement and
four replications was used. Treatments included five OPW dilutions
in supply water (SW): D1 (100% SW), D2 (75% SW + 25% OPW), D3 (50%
SW + 50% OPW), D4 (25% SW + 75% OPW), and D5 (100% OPW), combined
with four SA concentrations (0, 0.8, 1.6, and 2.4 mM) and two genotypes
(Junco and Crioula). Results show
that OPW, combined with SA, enables irrigation in semiarid regions,
reducing improper OPW disposal and promoting water conservation. The
average SA concentration of 1.3 mM alleviated saline stress effects
up to 2.63 dS m–1, enhancing biomass production
and seedling quality. The OPW-D3 dilution (50% SW + 50% OPW) was most
effective for seedling morphophysiology, with Junco showing the best quality and Crioula exhibiting
greater saline stress tolerance. These findings highlight the potential
of combining OPW and SA as a sustainable strategy for Barbados cherry
seedling production under saline conditions.