Abstract:

 Seed banking following internationally agreed standards is an important way for preserving collections of wild plant species ex situ; but this method is not suitable for desiccation sensitive species. Lauraceae comprehends some of the dominant species in the evergreen broadleaved forest in the south of China and contains many species both of ecological and economical importance. However, study on seed biology such as germination and desiccation tolerance of this family is scarce. Seeds of 9 species from 5 genera of this family were collected and their dormancy status and germination requirement were studied; also their desiccation tolerance were determined using a modified 100seed test. The results showed that seeds of Cinnamomum camphora probably have intermediate physiological dormancy; seeds of Actinodaphne forrestii, Actinodaphne obovata, Cinnamomum migao, Lindera metcalfiana var. dictyophylla, Lindera communis and Neolitsea polycarpa are nondeep physiological dormant; Seeds of Cinnamomum burmannii and Phoebe glaucophylla may have no or negligible dormancy. All 9 species lost seed viability after desiccated to 286%-716% moisture content while still retained considerable viability with moisture content ranged from 1732% to 4487% after moist storage; thus seeds of the 9 species are all desiccation sensitive and can not be stored at the conventional seed bank conditions.

Key words: Lauraceae, Seed, Dormancy status, Germination, Desiccation tolerance

摘要：

种子库是对野生植物进行长期迁地保存的重要手段，但不适用于种子脱水敏感的植物。樟科植物中有不少为我国南方常见的重要经济林木，许多种类具有较高的生态及经济价值，但关于其种子萌发及脱水耐性等生物学方面的研究资料十分缺乏。本研究选取来源于5个属的9种樟科植物，对其种子休眠及萌发特性进行了初步的研究并利用100粒种子法原理确定其脱水耐性。结果表明樟树 （Cinnamomum camphora） 种子可能具有中度生理休眠；毛尖树 （Actinodaphne forrestii）、倒卵叶黄肉楠 （Actinodaphneo bovata）、米槁 （Cinnamomum migao）、网叶山胡椒 （Lindera metcalfiana var. dictyophylla）、香叶树 （Lindera communis） 及多果新木姜子 （Neolitsea polycarpa） 的种子具有浅生理休眠；阴香 （Cinnamomum burmannii） 及粉叶楠 （Phoebe glaucophylla） 的种子可能不具有休眠。全部9种樟科植物种子在脱水到286%~716%含水量后均失去全部活力；而保湿保存的种子含水量保持在1732%~4487%之间，仍保持全部或大部分活力；因此该研究涉及的9种樟科植物都是脱水敏感性种子，不适合传统的种子库保存方法。

关键词: 樟科, 种子, 休眠, 萌发, 脱水耐性