摘要
本文观察了西双版纳生境下桫椤(Alsophila spinulosa (Hook.) Tryon)生物学特性。桫椤濒危的可能原因是:1.桫椤孢子寿命短,难萌发。2.孢子—原叶体—孢子体的生活周期长,并且在丝状体、原叶体和幼孢子体阶段,无特殊结构去抵抗和忍耐一切不利环境因子的影响。3.孢子萌发、形成配子和胚胎建成等过程对生境条件的要求严格,因此桫椤的分布受到很大的限制。在现代气候条件下,桫椤只能在温暖、湿润的热带、亚热带林地生存下来。一旦桫椤生栖的森林遭到破坏,桫椤随之死亡。4.桫椤是木本植物,生殖周期很长,不利于生存发展。5.桫椤根很不发达,树干内部的输导系统也较原始,只能适应空气和土壤湿润的生境。6.桫椤被人为的掠夺式的砍伐。针对以上情况,提出了保护这一种质资源的措施。
In this paper the authors report on the biological characteristics of Al-sophila spinulosa (Hook. ) Tryon. The reasons of endangering of this plant as follows. The life of the spores is too more short and the spores are very difficult to germinate. The biocycle from spore-prothallus-sporophyte is too long. They are very difficult to resist and tolerate adverse factors in variousenvironment.lt needs a strict habitat for spore germination gamete differentiation and embryogenesis.Therefore the distribution region is highly limited. And it is most suitable for Alsophila spinulosa to exist in the worm and humid tropical and subtropical forest under the contemporary climatic condition. When the forest which Alsophila spinulosa's life relys on is destroyed, the fern will be die. It is a woody plant. It has a long sexual cycle. The long sexual cycle makes the Alsophila spinulosa difficult to exist and develop. Because of owing poor adventitious roots and primitive vascular system, Alsophila spinulosa only adapts to humid habitats. Many of the ferns have been plundered by mankind.
In order to save the valuable gemplasm successfully, the folowing methods must be adopted. Lower temperature (10℃) and desiccating condition (relative humidity 30-50%) is of much help to storing spores and prolonging spore vitability. Using tissue culture techniques to propagate plantlets rapidly and cultivating the plantlets back to the original habitats. Moving the plants of Alsophila spinulosa from varies habitats into seminatuie protection areas for cultivation and conservation.Any forest which contains Alsophila spinulosa must be preserved.
出处
《云南植物研究》
CSCD
1990年第2期186-190,共5页
Acta Botanica Yunnanica
关键词
桫椤
孢子
生物学特性
濒危植物
Alsophila spinulosa
Spore. Biological charnctorislics
Endangering plant
