Effects of pre-storage hydration treatments on germination performance, moisture content, DNA synthesis and controlled deterioration tolerance of tomato (Lycopersicon esculentum Mill.) seeds

Abstract

AbstractStorage of tomato seeds under deteriorating conditions reduced the rate of germination, the uniformity of germination, total germination and the proportion of normal seedlings. Pre-storage humidification and hydropriming of seeds resulted in a significant increase in resistance to deterioration. In contrast, osmoprimed seeds were more deterioration sensitive. Humidification or hydropriming for one day did not allow nuclei to enter the S phase of the cell cycle. Osmopriming strongly increased the percentage of nuclei with replicated DNA in the embryonic root tip, indicating initiation of the cell cycle and progression towards the G2 phase. The interaction between the prestorage treatments, cell cycle progression and deterioration resistance, is discussed. Based on the changes in moisture content equilibrium and cell cycle activity it is hypothesized that the beneficial effects of pre-storage humidification and hydropriming were related to metabolic activities induced by the partial hydration and that the adverse effects of osmopriming were caused by a decrease in DNA repair activity due to progression in the cell cycle.