摘要
跟踪测定显胎生红树植物木榄(Bruguiera gymnorrhiza)胎生胚轴发育过程中的长度、密度、鲜重、干重、含水量、渗透势、五种主要无机渗透调节离子(Ca2+,Mg2+,Na+,K+,Cl-)浓度及含量的变化.结果表明:木榄胚轴在发育过程中不断积累有机营养物质以及盐分,并在母树上完成渗透调节、器官形成等生理过程;可以将木榄繁殖体的发育过程划分为果期、生长活跃期和成熟期3个阶段;比较胚轴和生境中土壤、海水的理化指标,可以得出木榄胚轴的密度、渗透势以及盐分水平的变化是以适应母树所处的高盐和周期性海水浸淹生境为目标;探讨了木榄胎生现象的生理生态学意义及适应方式.
Hypocotyls of Bruguiera gymnorrhiza were collected at various stages of development while still on the parent plant. Length, density, fresh weight, dry weight, water content, osmotic potential, ions concentrations and contents （Ca^2＋ , Mg^2＋ , Na^＋ , K^＋ , C1^- ） were determined. The result showed that the hypocotyls of B. gymnorrhiza undergoed some growth before becoming detached from the parent plant. They accumulated large amounts organic nutriments and ions during the development. The growth of hypocotyls could divided into 3 stages according to the changes of each physiology characteristics： The first 45 d was the fruit stage. The following 60 d were a period of highest activity after the hypocotyl emerged through the fruit wall. In the final 60 d before detachment, the seedlings came into being. The osmotic potential of mature hypocotyls B. gymnorrhiza was negative than that of the solution on whichtheir parent plant vegetated, while the ions concentrations were approaching to those of the solution on which their parent plant vegetating. Thus help the seedlings survive better in the flooding and saline conditions. The density of mature hypocotyls of B. gymnorrhiza were lower than seawater, thus the hypocotyls can float and be dispersed by tide.
出处
《海洋学报》
CAS
CSCD
北大核心
2006年第2期121-127,共7页
基金
国家自然科学基金资助项目(30200031)
福建省自然科学基金资助项目(B0410001)
关键词
木榄
胎生胚轴
发育
红树林
Bruguiera gymnorrhiza
hypocotyl
development
mangroves
