Influência do óxido nítrico na germinação de sementes de Plathymenia reticulata Benth com baixo vigor

The objective of this study was to investigate the nitric oxide (NO) action on the promotion of seeds germination with low vigor of Plathymenia reticulata. Accelerated aging on seeds were made per 24, 48 and 72 hours at 40°C as well as pre soaking in potassium nitrate (KNO3) and sodium nitroprussiate (SNP) solutions. The concentrations from zero (control), 0,01, 0,10, 1,0 and 10,0mMol.l-1 per six, 12, 18, and 24 hours were used. The accelerated aging period were followed by pre soaking in KNO3 and SNP. The electric conductivity and the activities of the enzymes superoxide dismutase (SOD) and catalase (CAT) were quantified. The best results of germination occurred with the pre soaked seeds in KNO3 and SNP during 24 hours and in 0,10mMol.l-1. The KNO3 and the SNP increased the germination of the aged seeds of P. reticulate. The accelerated aging increased the membrane permeability, which was reduced with the KNO3 and SNP treatments. The activity of SOD was greater in seeds treated with KNO 3 and SNP. The CAT activity did not show significant differences among the treatments, even when the seeds were soaked in KNO3 and SNP. It can be concluded that the nitric oxide increased the quality of the aged seeds by maintaining the membrane integrity and stimulus of the superoxide dismutase activity.