免费文献传递   相关文献

Seed Recalcitrance: a Current Assessment


Seeds have been categorized as orthodox, recalcitrant and intermediate seeds according to their dehydration behaviors. Identification of desiccation-tolerance and -sensitivity of seeds is the basis making storage strategy of seeds and long-term conservation of species gene resources. In addition to the inherent characteristics of the species, developmental status of the seeds, dehydration rate, and the conditions under which they are dried and subsequently re-imbibed are very important factors influencing desiccation tolerance of seeds. Survival, electrolyte leakage rate, and germination/growth rate produced by survived seeds are a excellent synthetic parameter when discussing desiccation tolerance of seeds. Desiccation tolerance of seeds is a quantitative feature. The term "critical water content" is incorrect and has caused some confusion in assessment of seed recalcitrance. A new working approach to quantify the degree of seed recalcitrance has been proposed in this paper.

种子顽拗性:最新评价
宋松泉  Patricia BERJAK nORMAN pammenter Tobias M. NTULI 傅家瑞
(1. 中国科学院西双版纳热带植物园,云南勐腊勐仑666303;
2. Plant Cell Biology Research Unit, School of Life and Enviironmental Sciences, Unixersity of Natal,Durban, 4041 South Africa; 3. 中山大学生命科学学院,广州510275

摘要: 根据种子的脱水行为,可以把种子分为正常性、顽拗性和中间性种子三种类型.种子脱水耐性和脱水敏感性的鉴定是制定种子的贮藏策略和物种基因资源长期保存的依据.除了物种的内在特性外,种子的发育状态、脱水速率、脱水时和重新水合时的环境是影响种子脱水耐性的重要因子.种子的存活率、电解质渗漏速率和存活种子的萌发生长速率是衡量种子脱水耐性的良好的综合参数.种子的脱水耐性是一种数量性状,用"临界含水量"的概念来判断是不正确的,且在评价种子顽拗性中引起了一些混乱.本文还提出了一种全新的评价种子顽拗性的工作模式.

关键词: 脱水耐性;脱水敏感性;正常性种子;顽拗性种子;中间性种子;脱水耐性的影响因子和评价参数;数量性状;临界含水量;种子顽拗性

通讯作者。Tel: 0691-8715474; E-mail: <sqsong@ xtbg.org.cn>。


全 文 :