Abstract
The important planting trees are about 60 species. Propagation by seeds to produce seedlings is major method. However, some tree seeds have dormancy and germinate poorly. Dormant seeds pretreated with cold stratification at 5℃ break seed dormancy and increase seed germination and rate. The objectives were first to collect seeds in the families of Fagaceae, Lauraceae and Ulmaceae, and to test at various temperatures to break seed dormancy and enhance germination, and second to seeding directly to containers or using emerged seeds to transplant to containers, and to investigate seedling height and seedling quality. Our goal is to reach a labor saving and low cost in nursery management. Results showed that (1) seeds of Trema orientalis incubated at 30/20 and 25/15℃ with 12 hours light a day began to germinate after 3 weeks incubation, and germinate to 70% after 18 weeks. Seeds of T. orientalis under red light and white light exhibited better germination than that of blue light. Seeds of T. orientalis under far-red light germinated 0%. Cold stratification at 5℃ increased the Trema seeds germination, and cold stratified seeds germinated to high percentage at dark environment. On the other hand, light is not a major factor in seed germination after cold stratification. (2) Seedling hight of Machilus kusanoi and M. zuihoensis after 1 year growth was 54.6cm and 69.9cm, respectively, and seedling ground diameter was 7.39mm and 6.36mm, respectively. Index of Sturdiness Quotient was 7.5 in seedlings of M. kusanoi and 11 in seedlings of M. zuihoensis. The Index of Sturdiness Quotient with green healthy features showed these seedlings exhibited good quality. The seedlings can be outplanted after 3 months hardening-off treatment. (3) Comparison of soil medium with different components showed that soil plus organic fertilizer, rice husk and vermiculite had seedlings grow better than the other two kinds of soil medium. (4) Seeds of Litsea cubeba (Lauraceae), Lithocarpus synbalanos (Fagaceae) and Lithocarpus hancei (Fagaceae) were collected and they are dormant. These dormant seeds are cold stratified at 5℃ for 3 months and will be seeded in February 2016.