Tolerância de algodoeiros naturalmente coloridos ao estresse salino cumulativo no terceiro ciclo de cultivo.

Abstract

Water quality in the Northeast is a limiting factor, the studies for the use of saline water being relevant to irrigate crops, as well as development of appropriate crop management practices and use of more tolerant species to salinity, such as the cotton. In this sense, the objective of this research was to evaluate the tolerance of colorful cotton genotypes to salt stress cumulative, varying the plant developmental stages to provide input to its cultivation in areas affected by salts. In an experiment conducted in a greenhouse of the Academic Unit of Agricultural Engineering, Campus of Campina Grande, were avaliadosdois cotton genotypes (G1 - BRS Ruby and G2 - BRS Safira), subjected to ten management strategies of salinity, varying water quality applied at different stages of the cycle of the plants, using seeds formed under salt stress in the preceding cultivation. Combined factors in a randomized block design, resulted in 20 treatments (2 x 10) with three plants per plot and three replications. growth variables were evaluated, physiological and production plants in different stages of dicilo plantas. Os data were submitted to analysis of variance by the 'F' test, comparing the averages Scott-Knott (p <0.05) management strategies of irrigation and Tukey test (p <0.05) for cotton genotypes. Among the genotypes BRS Ruby 'was the most sensitive to the salinity of the irrigation water (ECw 9 dS m-1), regardless of the stage of development. The application in the vegetative phase was detrimental to growth and development there is no recovery plant at flowering and fruiting.