ESTRESSE HÍDRICO E SALINO EM DIFERENTES TEMPERATURAS NA GERMINAÇÃO E VIGOR DE SEMENTES DE Phaseolus lunatus L.

Abstract

The Phaseolus lunatus L. species, popularly known as bean, lima bean or bean-to-file is used for human and animal consumption, for providing vegetable protein and decrease the almost exclusive reliance on common beans (Phaseolus vulgaris L.), which may also be used as compost or green cover crop for soil protection. The objective of this study was to evaluate the germination and vigor of the seeds when subjected to water and salt stress at different temperatures. To evaluate the germination simulating water stress condition polyethylene glycol solutions used were 6000 (PEG 6000) in different osmotic potentials of 0.0; -0.1; -0.2; -0.3; -0.4 And -0.5 MPa at temperatures of 20, 25, 30 and 35 ° C. While saline solutions were prepared using as the solute sodium chloride (NaCl) at concentrations of 0.0; 1.5; 3.0; 4.5 and 6.0 dS m-1 at temperatures of 20, 25, 30, 35 and 20-30 ° C. To determine the effect of the treatments evaluated the percentage, first count and germination speed index and the length and seedling dry matter. The PEG 6000 solution at potentials above -0.4 MPa inhibit germination and seed vigor unfeasible Phaseolus lunatus L., better suiting to 25 ° C. Salt stress induced by NaCl to the potential of 1.5 dS m-1, does not affect the germination of seeds of this species performance, and better performance under alternating temperature of 20-30°C.