Practical methods for rapid seed germination from seed coat-imposed dormancy of Prunus yedoensis

Abstract

The seeds of Prunus yedoensis have slow and poor germination when intact (with endocarp). Cold and/or warm stratification, washing, and scarification with liquid nitrogen and sulfuric acid, in combination with or without gibberellic acid (GA3) application, were investigated as facilitators for rapid and high germination. No germination was observed without GA3 in any treatment for intact seeds. GA3 treatment for one day significantly shortens the mean germination time (MGT) and improves seed germination percentage. Immersion in liquid nitrogen followed by GA3 treatment, GA3 application to intact seeds and seed coat removed seeds significantly enhanced the germination and MGT to 63 ± 7.6% (8.6 weeks), 71 ± 5.0% (4.7 weeks), and 93 ± 5.1% (0.8 weeks), compared to untreated seeds or stratified seeds (0%) chilled for six months. Depending on the GA3 application method, results could be different in intact seeds. GA3 application with vigorous shaking accomplished higher germination and lower MGT (71 ± 5.0%, 4.7 weeks) than gentle shaking incubation (33 ± 6.0%, 10.4 weeks). The germination inhibitor(s) were located in the seed coat because seed coat extract inhibited germination in decoated seeds. Therefore, coat removal alleviates the inability to promote germination and it has the same beneficial effect as does the application of GA3. According to the results, it suggest that the effective application of GA3 on intact seeds or seed coat removal could overcome seed dormancy in P. yedoensis.