Semi-arid regions present the inherent problem of accumulation of salts in the soil due to the use of brackish water for irrigation, and water deficit compromises the growth and physiological indices of crops. This study evaluated the effect of salt and water stress on growth and gas exchange in the zucchini cv. Caserta crop. The study was conducted at the University of International Integration of Afro-Brazilian Lusophony, Redenção, Ceará State, Brazil. The experimental design was completely randomized, in a 5 × 2 factorial scheme with five levels of electrical conductivity of the irrigation water - ECw (0.5, 1.0, 1.5, 2.0, and 2.5 dS m-1) and two water regimes (50 and 100% of the potential crop evapotranspiration - ETc), with five replicates. At 36 days after sowing, the following traits were evaluated: CO2 assimilation rate, transpiration, stomatal conductance, internal carbon concentration, leaf temperature, relative chlorophyll index, and water use efficiency. At 45 days after sowing, the plant height, stem diameter, number of leaves, and leaf area were also evaluated. The use of brackish water (1 to 2.5 dS m-1) reduced the growth parameters of zucchini cv. Caserta. The increase in ECw caused a decline in the physiological traits. Under 100% ETc, higher values of CO2 assimilation rate, transpiration, and instantaneous water use efficiency were recorded, and there was 50% ETc for internal carbon concentration, even with the increase in ECw.

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Salt stress negatively affects the sense, the objective of this work was to evaluate growth and soil saturation extract parameters (EC and pH) in cowpea crop irrigated with saline water under different leaching fractions. The experiment was conducted in the experimental area of the Auroras Seedling Production Unit, which belongs to the Universidade da Integração Internacional da Lusofonia Afro used was entirely randomized, in a 5x2 factorial scheme, referring to five 15 and 20%) and two electrical conductivities of the irrigation water (0.3 and 4.0 dS m repetitions. The leaf area, aboveground and root dry mass were negatively affected with the increase of the leaching fraction, however, with less intensity with water of lower salinity. Increasing the leaching fraction increased the number of leaves, stem diameter, and pH, but more efficiently with the lower salinity water. The increase of the leaching fraction associated with increased the electrical conductivity of the