Seed viability tests for Acer pictum and A-rubrum

摘要

Seed viability is commonly used to rapidly evaluate the seed quality, especially for the seeds with deep dormancies. To establish the experimental protocol that could obtain reliable seed viability for Acer pictum and A. rubrum, different treatments were examined in excised embryo and tetrazolium (TZ) tests. In the excised embryo test, it was found that sterilization could get a significantly higher viability for both species. No significant difference was observed between seed viability and seed germination percentage when the excised embryos were sterilized following the protocol established in this study, indicating it was appropriate for evaluation of seed quality of these two maples. In the TZ test, we examined the effect of GA(3) and stratification treatment on seed viability for these two species. For seeds of A. pictum, no significant difference was detected between the viabilities of seeds merely rehydrated with water and those rehydrated with GA(3) and stratification. Both protocols yielded seed viabilities that deviated insignificantly from the seed germination percentage. Thus, additional treatments other than water immersion were unnecessary to measure the seeds viability of A. pictum. By contrast, significant difference was observed for seed viabilities of A. rubrum under the above different rehydration methods. Only when seeds were rehydrated with GA(3) and stratification after water immersion yielded seed viability that was insignificantly different from seed germination percentage. Therefore, besides water immersion, additional treatments were compulsory for seed viability evaluation of A. rubrum. In this study, we also found that the radicle tip of a high percentage of A. rubrum embryos could only be partially stained in the TZ test, and this scenario was not related to the embryo colors of A. rubrum.