Growth and Photosynthetic Pigments of Cotton Cultivars Irrigated with Saline Water
The cultivation of cotton is a relevant socioeconomic activity in the Brazilian agricultural scenario. In the Brazilian Northeast, however, production is limited by low rainfall, requiring water supplementation, a problem for the cotton cultivation practiced in the semi-arid region, due to the presence of saline ions in several water sources, from where the water is used for irrigation. It is necessary to identify cultivars that better tolerate saline stress in order to provide subsidies for their cultivation under such conditions. In this sense, the objective was to evaluate the tolerance of cotton cultivars to salinity. The experiment was conducted in a greenhouse, belonging to the Natural Resource Technology Center of the Federal University of Campina Grande, Campus I, Campina Grande, Brazil, in a completely randomized design in a 2 × 5 factorial scheme, with four replications, totaling 40 experimental units (BRS 368 RF and BRS SAFIRA) submitted to five saline levels (1.5, 3.0, 4.5, 6.0 and 7.5 dS∙m−1 ). Irrigation with water saline of EC from 1.5 dS∙m−1 affects adversely the growth of cotton cultivars, causing reductions in plant height, stem diameter, leaf area and number of leaves. Saline stress reduced the levels of the photosynthetic pigments of the cotton plants studied.