Carrot seed germination in different conditions of salinity and temperature

The success of the germination process depends on the entry of water through the tissues that enclose the embryo. The presence of salts reduces the gradient between the ground and the surface of the seed, restricting the absorption of water by the seed. The objective of the experiment was to evaluate the effect of salinity and temperature on the germination of carrot seeds. The osmotic potentials utilized in the solutions were 0.0 (control); -0.4; -0.8; -1.2, -1.6 and -2.0 MPa. obtained with the use of NaCl p.a.; the temperatures used were 15 °C, 20 °C, 25 °C, 35 °C, 15-35 °C and 25-35 °C. A commercial variety of carrot seeds, the 'Brasilia' cultivar, was used. Percentage germination, germination speed index, fresh and dry mass of seedlings were determined. The averages were subjected to analysis of regression. Germination was reduced by the temperature of 35 °C and by osmotic potentials greater than -0.8 MPa. Temperatures of 20 °C and 25 °C are more favorable to the germination of seeds in the GSI salt conditions tested.