MORFOFISIOLOGIA DO CRESCIMENTO INICIAL DE CAFEEIROS SOB SALINIDADE DA ÁGUA DE IRRIGAÇÃO

Abstract

The intensity of salt stress on the plant depends on tolerance, which varies between species and between genotypes of the same species. The objective of this work was to evaluate the effects of irrigation water salinity on the initial vegetative growth, gas exchange, electrolyte leakage, and water status of coffee canephora clones. The experiment was carried out in a greenhouse using a randomized block experimental design, in a 5x2 factorial scheme, with four replications, with five electrical conductivities of the irrigation water (ECw): 0.08; 0.88; 1.68; 2.48, and 3.28 dS m^-1 and two clones: C08 and C25. There was an interaction effect between salinity and clones only for leaf area at 60 days after transplanting (DAT). The ECw above 0.08 dS m^-1 caused a reduction in stomatal conductance, internal CO₂ concentration, transpiration, CO₂ assimilation rate, number of leaves, plant height, stem diameter, leaf area, fresh and dry biomass aerial part, root dryness, and root/shoot ratio at 60 DAT, and in relative water content in leaf tissues and cell membrane damage at 30 and 60 DAT. There was a significant effect of clones only for plant height at 30 and 60 DAT.