Osmotic stress on seeds genetically transformed tobacco plants

Salinity and drought stress limit the productivity of several crops, thus studies related to the genetic transformation of seeds in a model plant, such as tobacco, can be an alternative to minimize negative impacts caused by environmental conditions. The objective of this work was to evaluate the tolerance of osmotic stress on seeds of genetically transformed tobacco plants with the introduction of the gene synthesizer of proline ( p5csf129a ), under saline and drought stress conditions. For this was employed five events with differences in proline content, ranging the content of 0.70 to 10.47 µmoles g -1 of fresh mass. The saline concentrations used were: zero (distilled water); 50; 100; 150 and 200 mmol L -1 of NaCl; already for the drought stress, simulated with PEG 6000, worked up with the following osmotic potentials: zero (distilled water); -0.2; -0.4; -0.6 e -0.8 MPa. Each treatment tested was evaluated by germination test, first germination count and speed germination index. It is concluded that the seeds of genetically transformed tobacco plants with overexpression of the gene p5csf129a , synthesizer of proline, are more tolerant to osmotic stresses. At the conditions tested, tabacco seeds with proline content of 10.47 µmol g -1 exhibit superior perfomance, revealing higher potential physiological.