Efeito da salinidade na qualidade fisiológica de sementes de arroz e feijão submetidas a estresse salino

Abstract

Experiments were carried out to evaluate the physiological quality of seeds and the growth of the rice seedlings cv. EL I Passo L 144 and bean cv. FT Nobre, treated with solutions of sodium chloride (NaCl), in the different concentrations zero; 30; 60; 90; 120 and 150 mm. This, used viability tests, vigour and characteristics of the growth. The germination and the emergency rice seeds were negatively affected in the concentrations of 120 and 150 mM of NaCl, the bean seeds already show reduction in the percentage of the germination, but the emergency index was affected drastically, for all the appraised salinity levels. The speed of emergency of both species showed decrease in the highest concentrations of NaCl. The fresh and dry matters of the shoot and roots of bean seedlings reduced with increment in salt concentrations, but for the rice, the salinity didn't affect significantly this cultivar. The length of shoots part of the rice seedlings and of bean decreased drastically with increase of the salinity. In the test of electric conductivity with zero, three and 24 hours of incubation, the rice seeds and of bean presented larger liberation of having leached, in the largest concentrations of NaCl. The total chlorophyll content, of bean seedlings presented significant differences in the largest salinity levels (120 and 150 mM of NaCl), but they didn't differ for the seedlings of rice. Therefore, in the conditions that the work was accomplished we can conclude that the salinity doesn't have effect in the absorption of water. However, the physiological quality and the seeds growth of both species are committed for the growing levels of the sodium chloride.