INFLUÊNCIA DA SALINIDADE DA ÁGUA E DO MODO DE IRRIGAÇÃO NO TEOR DE CLOROFILA TOTAL DE PLANTAS ORNAMENTAIS

The objective of this study was to evaluate the influence of increasing salinity of water and irrigation mode on the total chlorophyll content of four ornamental species. The experiment was conducted in a greenhouse at the Pici campus, Federal University of Ceará, 1 Doutorando, PPGCS/UFRPE. Recife – Pernambuco. Email: italooliveiraufpb@gmail.com; 2 Doutorandos, PPGCS/UFC. Fortaleza – Ceará. Email: juliamedeirosagro@gmail.com; regismta@bol.com.br; 3 Doutores, Professor Associado, PPGEA/UFC. Fortaleza – Ceará. Email: claudivan_@hotmail.com; 4 Doutor, PPGEA/UFC. Fortaleza – Ceará. Email: sousaibiapina@yahoo.com.br; leilaneves7@hotmail.com; F. Í. F. de Oliveira et al. Fortaleza, State Ceará, Brazil. The experimental design was a randomized complete block design with four replications, six increasing levels of electrical conductivity of the irrigation water in the plots (0.6, 1.2, 1.8, 2.4, 3.0 and 3.6 dS m), two irrigation modes in the subplots (localized irrigation and non-localized irrigation) and four ornamental species in the subsubparcels (Catharanthus roseus; Allamanda cathartica; Ixora coccinea and Duranta erecta). The plants were evaluated at 15, 30, 45 and 60 days after the beginning of the saline treatments, the readings were performed in three leaves per plant, located in the middle third of the plants. There was a significant effect (p <0.01) of the sources of variation and their interactions on the total chlorophyll content of ornamental plants. The species Duranta erecta presented the greatest decrease relative to salinity increase, both in the localized irrigation mode (20.7%) and in the non-localized irrigation mode (24.9%). The increase in the electrical conductivity of the irrigation water negatively affects the total chlorophyll content of the ornamental species, regardless of the mode of irrigation used.