|
Effects of seed viability, storage conditions, and chemicals added to priming solution on breaking dormancy and germinability ware studied in perilla. Ca(NO₃)₂ at 200 mM was the most effective in reducing the days to 50% of the final germination percentage (T_(50)). Seeds primed at 20℃ for 4 days germinated most rapidly at all temperature regimes tested. Washing after priming slightly increased the T_(50) values. Air-drying for 2h at room temperature after priming maintained all the advantages achieved during priming treatment. However rate at 50℃ significantly reduced germination and beneficial effects of priming were lost. The addition of 50 μM GA₃ to Ca(NO₃)₂ solution resulted in breaking dormancy with higher percent germination when perilla seeds were germinated at 20℃. Seed priming induced earlier germination in all ten cultivars tested. However, the degree of its effectiveness differed depending on cultivars. The addition of 50 μM GA₃ in priming solution showed higher percent germination and shorter T5o than those of priming alone, when the seeds were germinated at 10, 15, 20, and 25℃. The effectiveness of priming in reducing the TSp was greater when the seeds were germinated at 10 to 15℃ than at optimum temperatures. Viability and germination of perilla seeds were severely reduced after 10 months of storage at 30℃. But no deleterious effect was observed in seeds stored at 5℃ for same period. The loss of seed germinability due to storage could be restored by seed priming.
|