Avaliação do crescimento de plantas de feijão-de-corda em função da salinidade e da composição iônica da água de irrigação.

Abstract

The water use of inadequate quality in the irrigation can cause serious damages as much to the soil how much to the plants. The objective of this work was to evaluate the effect of salinity and chemical composition of irrigation water on plant growth of cowpea plants [Vigna unguiculata (L.) Walp.] cv. Pitiúba. Plants were cultivated in plastics pots, using 22 kg of soil at greenhouse conditions and subjected to four different salt stress concentrations (0,5; 1,5; 3,0 and 4,5 dS.m-1) in irrigation water obtained by adding NaCl, CaCl2.2H2O and MgCl2.6H2O (A1); a mixture of chloride, sulphate, carbonates, and bi-carbonates salts (A2), or alone NaCl (A3). A completely randomized design, in a factorial arrangement (3 x 4), with five replicates was adopted. After 48 days sowing they were measured fresh and dry masses of leaves, stems and roots. The salinity of irrigation water caused reduction in the biomass production, but it was not observed effects of the chemical composition of water on these parameters.