Atributos químicos de neossolo flúvico do semiárido de Pernambuco cultivado com tomateiro irrigado com águas salinas

Abstract

The increasing demand for food in the world makes irrigation a technique of fundamental importance, especially in arid and semi-arid regions, like much of the Brazilian Northeast, where drought occurs in most of the year. However, the use of irrigation without proper management of soil-water-plant-salinity may cause serious environmental problems, social and economic. Given the above the aim of this study was to evaluate the development of three tomato cultivars (IPA-7, Redenção and SM-16) and changes in Fluvic Neossoil chemical properties of Cachoeira II Irrigated Perimeter soil irrigated with water of different salinity and sodium adsorption ratio (SAR). The work was conducted in a greenhouse, using the three tomato cultivars irrigated with solutions prepared to correspond to six values of electrical conductivity (EC) and two of sodium adsorption ratio (SAR), combined as salinity treatments. The experimental design was randomized blocks with disposition factorial 3 x 6 x 2 (three tomato cultivars, six EC and two SAR) with four replications, totaling 144 experimental units. The variables studied were fresh leaves (FLM) and leaf dry matter (LDM) stem fresh weight (SFW), dry stem (DSM), plant height (PHE), stem diameter (SD) and number of leaves (NF) content of the elements Ca2 +, Mg2 +, K+ and Na+ in shoots of the plant; Ca2+, Mg2+, K+ and Na+ and soluble, pH, EC and SAR of saturation extracts of soil and percentage of saturation by sodium (ESP) of soil. Irrigation with water of different salinities caused: significant changes in variables FLM, LDM, SFW and PHE, increased levels of calcium and sodium in dry tomato leaves, where calcium was the element found in greater concentration, increase in content exchangeable sodium, the PST, the SAR and EC of saturation extract of soil indicating changes in the processes of salinization and sodification; was no reduction in growth variables due to the increase in salinity of irrigation solution, however, the RAS water Irrigation did not affect significantly the growth parameters of tomato. It was found, increased the accumulation of elements in plant dry matter with increasing salinity of irrigation water. Calcium was the predominant ion in dry matter, observing an increase of sodium with increasing salinity and SAR waters used. The waters of increasing salinity caused an increase in content of exchangeable sodium, the ESP, the SAR and EC of the soil, indicating changes in the processes of salinization and sodification