Prolonged storage reduced the positive effect of hydropriming in Chinese cabbage seeds stored at different temperatures

Abstract

Primed seeds generally deteriorate and lose beneficial effects of priming during subsequent dry storage. Therefore, it is necessary to determine how long the positive effects of priming could maintain in primed seeds stored at ambient temperature. In present study, naturally aged Chinese cabbage seeds were hydroprimed at 20°C in the dark for 10h. The primed seed were stored at 4, 20 or 30°C, respectively, and samples were tested at regular intervals (1, 3, 6 and 9months). Results indicated that the germination attributes (germination percentage, germination rate and seedling vigor index) of primed Chinese cabbage seeds stored at 30°C for 9months significantly decreased compared with un-stored primed seeds, even worse than non-primed seeds. However, such negative effects were not observed in primed seeds stored at 4°Cand 20°C for 9months and 30°C for 6months. The diminished beneficial effects of hydropriming can be attributed to decreased activities of peroxidase (POD) and catalase (CAT), soluble sugar and soluble protein content, with increased malondialdehyde (MDA) in primed Chinese cabbage seeds.