PDF(Sci-hub)
Abstract：
Meaningful conservation techniques for the endangered Morus boninensis require seed production and storage, since in situ purebred seed production is infrequent in Ogasawara Islands (World Natural Heritage Site) in Japan. Ex situ living M. boninensis specimens produced seeds by open- and artificial-pollination in a greenhouse. Seed desiccation tolerance and storage characteristics were examined. Open-pollinated seeds were dried at 75, 33 and 8% relative humidity (RH) for 5 days then cryopreserved at -170 °C. Artificially pollinated seeds were dried at 8% RH then stored cryogenically at -170 °C and in freezers at -80 or -20 °C for 6 months. Germination rates were compared among seeds before and after drying and storage. Germination rates of undried seeds were 83% for open-pollinated seeds and 65% for artificially pollinated seeds. M. boninensis seeds exhibited the characteristic high desiccation tolerance of orthodox seeds and maintained a high germination rate after drying to a moisture content of approximately 4%. Cryopreservation of open-pollinated dry seeds with moisture contents of ca. 12, 7 and 4% maintained germination rates, while cryopreservation of undried seeds (moisture content ca. 44%) resulted in no germinability. Cryogenic and freezer storage of artificially pollinated dry seeds for 6 months resulted in maintenance of germination rates comparable to undried seeds before storage. Seed production was enabled by ex situ M. boninensis collection. The present study also developed a method for low temperature seed storage. Ex situ living tree collection represents a feasible seed resource for reintroduction and restoration programmes for M. boninensis.
摘要：
濒危桑树的有意义的保护技术需要种子的生产和储存，因为在日本的小gas原群岛（世界自然遗产）很少生产纯种种子。在温室中通过开放式和人工授粉产生种子。检查了种子的脱水耐受性和储存特性。将开放授粉的种子在75、33和8%相对湿度(RH)下干燥5天,然后在-170°C下冷冻保存。人工授粉的种子在8%RH下干燥,然后在-170°C下低温储存,并在-80或-20°C下在冰柜中储存6个月。比较干燥和储存前后种子的发芽率。未干燥种子的发芽率对于开放授粉的种子为83％，对于人工授粉的种子为65％。M.boninensis种子表现出正统种子特有的高脱水耐受性，并在干燥至约4％的水分含量后保持了高发芽率。水分含量约为的开放式授粉干种子的冷冻保存。保持12、7和4%的发芽率，同时冷冻保存未干燥的种子（水分含量约44%)导致无发芽。人工授粉的干种子的低温和冷冻储存6个月可保持与储存前未干燥种子相当的发芽率。种子生产是通过异位收集来实现的。本研究还开发了一种低温种子贮藏方法。异位活树的采集代表了一种可行的种子资源，可用于博宁纳氏菌的重新引入和恢复计划。
