Quality of yellow passion fruit seedlings under saline water irrigation and salicylic acid concentrations

Abstract

The objective of this study was to evaluate the quality of „BRS Gigante Amarelo‟ passion fruit seedlings irrigated with brackish waters under salicylic acid application. The experiment was conducted under conditions of protected environment (screened) in the experimental area of the Federal Rural University of the Semiarid Region (UFERSA), Multidisciplinary Campus of Caraúbas, RN, Brazil, in the period from August to November 2022, in a randomized block experimental design and analyzed in a 4 x 4 factorial scheme, with four replicates and one plant per plot, with treatments consisting of electrical conductivity of irrigation water - ECw (0.5, 1.4, 2.3 and 3.2 dS m-1) and concentrations of salicylic acid - SA (0.0, 1.5, 3.0, and 4.5 mM L-1). Electrical conductivity of irrigation water up to 3.2 dS m-1 does not affect the absolute growth, photosynthetic rate and quality of „BRS Gigante Amarelo‟ passion fruit seedlings; ECw from the average value of 1.3 dS m-1 affects stomatal conductance, transpiration, internal CO2 concentration and root fresh and dry mass production. Foliar application of salicylic acid does not mitigate the effect of salt stress from irrigation water on the production of yellow passion fruit seedlings; however, the average concentration of 3.15 mM L-1 promotes greater absolute and relative growth, shoot fresh and dry mass and quality of seedlings. SA concentration of 1.5 mM L-1, associated with ECw of 1.0 dS m-1, is recommended for the production of “BRS Gigante Amarelo” passion fruit seedlings.