Abstract

Japanese Stewartia, Stewartia pseudocamellia (Maxim.), seeds were extracted from immature capsules and handled under nondesiccating conditions. Moisture content of fresh seeds was 82%. After exposing seeds for 48 hrs at room conditions seed moisture content was 56% and after 24 hrs at 80C (176F) it was 49%. Both ambient and 80C (176F) drying conditions resulted in complete loss of viability based on a tetazolium test. Exposing seeds to a 24 hr aerated water soak in 1 mM gibberellic acid (GA₃), and a 3 month warm (25C, 77F) stratification period increased seed germination only after 6 months of cold (4C, 40F) stratification compared to seeds given a 24 hr aerated water soak without GA₃ and similar warm and cold stratification periods. Best management practices for handling and germination of fresh Japanese Stewartia seeds are: (a) harvest seed capsules when they turn from green to brown, (b) maintain seeds under nondesiccating conditions, (c) treat seeds with a 24 hr aerated water soak in 1 mM GA₃ before a 3-month warm stratification, and (d) provide at least 7 months cold stratification.