Germination of Dimorphandra mollis Benth. seeds: effect of salinity and osmotic conditioning

Abstract

This work aimed to study the effects of salt stress and the osmotic conditioning on the physiological quality of D. mollis seeds. It was carried out two experiments with previously acetone imbibed seeds for dormancy release. The first one evaluated the effect of CaCl2 and NaCl saline solutions osmotic potentials at: 0.0 (control), -0.4, -0.8, -1.5 and -2.0 MPa on seeds percentage germination and germination speed index of 2006 seeds lot.  In the second experiment, the faveiro seeds were imbibed in polyethyleneglicol solutions (PEG 6000) at 0,0 (control), -0.3, -0.7, -1.0 and -1.3 MPa potentials. The different concentration levels of CaCl2 and NaCl affected negatively the seeds physiological quality, reduced significantly the germination and IVG. The seeds osmotic conditioning at -0.3 and -0.7 MPa provided a significant increment in the seeds germination percentage and germination speed index. The osmotic conditioning presented favorable immediate effects, accelerating the D. mollis seeds germination.