梨蒴珠藓孢子萌发与原丝体发育特征研究

为了解梨蒴珠藓（Bartramia pomiformis）孢子萌发和原丝体发育特征,在显微镜下观察室内人工培养的梨蒴珠藓单倍配子体发育过程。结果表明,梨蒴珠藓孢子吸水膨胀5 d后,开始破壁萌发,原丝体系统以丝状绿丝体为主,轴丝体在绿丝体上分化产生。培养22 d后,配子体在轴丝体细胞上分化产生。参照Nishida的标准,梨蒴珠藓孢子萌发类型为真藓型（Bryum-type）。这为梨蒴珠藓的人工扩繁提供了发育学基础资料。     

中华缩叶藓孢子萌发与原丝体发育特征研究

通过室内人工培养中华缩叶藓的孢子,在光学显微镜下详细观察了其孢子萌发、原丝体发育及配子体发生的全过程.结果表明:中华缩叶藓的孢子在壁内萌发,随后分裂产生块状原丝体;块状原丝体上可产生两种丝状体,一种是具疣的棒状原丝体,另一种是由长圆柱状细胞组成的轴丝体;配子体原始细胞只产生于块状原丝体上.根据中华缩叶藓的孢子萌发和原丝体发育特征,并参照Nishida对藓类植物孢子萌发类型的划分,确定中华缩叶藓的萌发孢子型应属于缩叶藓型(Ptychomitrium-type).     

五种藓类植物的孢子萌发与原丝体发育

本文对中华缩叶藓(Ptychomitrium sinense)、狭叶缩叶藓(P.linearifolium)、威氏缩叶藓(P.wilsonii)、葫芦藓(Funaria hygrometrica)和立碗藓(Physcomitrium sphaericum)5种国产藓类植物的孢子萌发和原丝体发育进行研究,结果表明不同藓类孢子萌发和原丝体发育类型不同,孢子萌发和原丝体发育方式与藓类植物的生态环境有关.     

五种藓类植物的孢子萌发与原丝体发育

本文对中华缩叶藓(Ptychomitrium sinense)、狭叶缩叶藓(P. linearifolium)、威氏缩叶藓(P．wilsonii)、葫芦藓(Funaria hygrometrica )和立碗藓(Physcomitrium sphaericum ) 5种国产藓类植物的孢子萌发和原丝体发育进行研究, 结果表明不同藓类孢子萌发和原丝体发育类型不同, 孢子萌发和原丝体发育方式与藓类植物的生态环境有关。     

垂蒴真藓原丝体发育特征的研究

在室内培养垂蒴真藓(Bryum uliginosum)孢子的基础上,对其孢子萌发、原丝体发育及配子体发生的全过程进行了跟踪观察。结果表明：该种孢子萌发后直接产生绿丝体。而轴丝体和假根仅在绿丝体上产生;配子体原始细胞产生于绿丝体基部细胞或轴丝体上。由此可以看出：垂蒴真藓属于真藓型孢子萌发型(Bryum-type)。     

中国藓类植物孢子萌发和原丝体发育的初步研究

关于苔藓植物的孢子萌发(Spore Germination)和原丝体发育(ProtonemaDevelopment)的研究,对阐明苔藓植物的各分类群之间的关系和种系发生及系统演化等有重要意义。虽然早在1782年J. Heduing就报告过藓类植物的原丝体形态,但后来长时间内研究较少,直到20世纪50年代开始增多了研究者从事本项工作。到1978年     

三种植物生长调节剂对密叶绢藓（Entodon challengeri）孢子萌发、原丝体发育及芽体发生的影响

研究了3种植物生长调节剂苯基噻二唑基脲(TDZ)、6-苄基腺嘌呤(6-BA)、萘乙酸(NAA)对密叶绢藓[Entodon challengeri(Paris)Cardot]孢子萌发、原丝体发育及芽体发生的影响,并对整个发育过程进行了显微观察和照相,结果表明:(1)3种植物生长调节剂对密叶绢藓孢子萌发影响不显著;(2)在原丝体发育阶段,1.0 mg/LNAA对原丝体初期的发育促进效果显著,0.4 mg/L TDZ对原丝体发育中期分枝的形成促进效果显著,6-BA处理效果不显著;(3)3种植物生长调节剂单独处理均促进芽体的发生,但0.4 mg/L TDZ效果最佳。而1.5 mg/L 6-BA TDZ组合处理效果更加显著;(4)芽体的发生数量与芽体的长势无正相关性。     

苔藓植物孢子萌发与原丝体发育研究进展

孢子萌发与原丝体发育对于研究苔藓植物以及其他植物类群的系统发育与系统演化有着十分重要的作用。本文综述苔藓植物孢子萌发类型、原丝体发育特征以及环境影响因子等,还介绍了20世纪90年代以来该领域研究的新进展,如人们以苔藓植物原丝体为实验材料进一步揭示Ca2 ．CAM信号系统、植物激素、光信号系统等在植物体内的作用机制。     

苔藓植物孢子萌发与原丝体发育研究进展

孢子萌发与原丝体发育对于研究苔藓植物以及其他植物类群的系统发育与系统演化有着十分重要的作用。本文综述苔藓植物孢子萌发类型、原丝体发育特征以及环境影响因子等,还介绍了20世纪90年代以来该领域研究的新进展,如人们以苔藓植物原丝体为实验材料进一步揭示Ca2+·CAM信号系统、、植物激素、光信号系统等在植物体内的作用机制。     

光照和温度对尖叶拟船叶藓孢子萌发及原丝体发育的影响

用组织培养法和光学显微镜技术初步研究了光照和温度对尖叶拟船叶藓孢子萌发及原丝体发育的影响。结果表明：（1）光照是影响孢子萌发的主要环境因子,20℃环境下,24h光照4d的孢子萌发率达83.3％;温度下黑暗培养的孢子30d也不能萌发,转光照后4d的萌发率可达84.6％;（2）温度是影响原丝体发育的主要环境因子,连续光照下,20℃的原丝体生长最快、分枝最多、分化最早,第31天可长达651.64μm;25℃次之,只有379.12μm;而自然光照下5-10℃环境下的孢子萌发率（18d为70.2％）和原丝体生长速度（127.44μm）均最慢;（3）原丝体发育到一定阶段,断裂为单个细胞,单个细胞再萌芽出新原丝体。     

Characteristics of spore germination and protonemal development in Hypnum pacleseens

The spore germination, protonemal development, and gametophyte differentiation of Hypnum pacleseens were observed in cultivation. Photomicrographs showed that spore germination of Hypnum pacleseens occured within the exospore. Its protonema is massive with filamentous chloronema formed inside. The terminal part of the chloronema differentiated into filamentous caulonema and its rhizoid was derived from the apical cell of the filamentous chloronema. The initial cell of gametophyte differentiated from chloronema and caulonema. Sporeling-type of Hypnum pacleseens is developmentally similar to Glyphmitrium-type.     

Characteristics of spore germination and protonemal development in Hypnum pacleseens

The spore germination,protonemal development,and gametophyte differentiation of Hypnum pacleseens were observed in cultivation.Photomicrographs showed that spore germination of Hypnum pacleseens occured within the exospore.Its protonema is massive with filamentous chloronema formed inside.The terminal part of the chloronema differentiated into filamentous caulonema and its rhizoid was derived from the apical cell of the filamentous chloronema.The initial cell of gametophyte differentiated from chloronema and caulonema.Sporeling type of Hypnum pacleseens is developmentally similar to Glyphmitrium-type.     

野雉尾金粉蕨配子体发育及其系统学意义

野雉尾金粉蕨为中国蕨科金粉蕨属植物,而金粉蕨属的系统位置一直存在争议。该研究用原生境腐殖土和改良克诺普氏(Knop’s)营养液对野雉尾金粉蕨的孢子进行培养,培养条件为温度25℃、光照强度2 500 lx、光照12 h/d,在光学显微镜下观察记录其孢子萌发和配子体发育过程。结果表明:野雉尾金粉蕨的孢子为黄褐色,四面体型,三裂缝,赤道面观为扇形,具周壁,外壁表面具网状纹饰。孢子培养7 d后开始萌发,孢子萌发类型为书带蕨型(Vittaria-type)。孢子萌发后,配子体原始细胞经多次横向分裂形成3~9个细胞的丝状体,丝状体细胞呈圆筒形,壁薄,侧壁向外鼓起,含有颗粒较大且数量较多的叶绿体。15 d左右发育为片状体,片状体多为匙状。25 d左右形成幼原叶体,幼原叶体不对称,配子体发育类型为水蕨型(Ceratopteris-type)。在原叶体发育过程中分枝丝状体非常发达,配子体呈丛状生长,整个发育过程没有毛状体产生。野雉尾金粉蕨的假根为单细胞管状,偶有分支,内无叶绿体。45 d左右精子器开始出现,精子器顶面观近圆形,侧面观为近椭圆形或短柱状。精子器成熟时,盖细胞裂开,精子逸出。60 d左右颈卵器出现,颈卵器比较大,基部略大于顶部,侧面观呈烟囱状,顶面观为铜钱状,颈部由四列细胞构成。90 d左右发育出肉眼可见的幼孢子体。从研究结果看,其配子体发育的特征与凤尾蕨科(Pteridaceae)凤尾蕨属(Pteris L.)相似,支持金粉蕨属归于凤尾蕨科的观点。该研究结果为野雉尾金粉蕨系统学研究提供了配子体发育方面的证据。     

四回毛枝蕨配子体发育的研究

采用MS培养基培养四回毛枝蕨孢子,利用光学显微镜详细观察记录了其孢子萌发、配子体发育及幼孢子体形成的整个过程。结果表明:成熟的孢子黑褐色,不透明,极面观圆球形,赤道面观蚕豆型,单裂缝,表面微褶皱。播种后8d左右萌发,萌发类型为书带蕨型,配子体发育为三叉蕨型。播种20d左右发育为片状体。播种30d左右形成幼原叶体,幼原叶体暂不对称,成熟原叶体呈蝴蝶形。原叶体边缘及背腹面都具毛状体,数量丰富,单细胞。播种50d左右开始有性器官出现,精子器近圆球形,由3细胞构成,成熟颈卵器颈部由5列细胞构成。原叶体受精后1月内可看到幼胚生成。     

Inhibition of Ageratina adenophora on spore germination and gametophyte development of Macrothelypteris torresiana

Allalopathy of Ageratina adenophora plays an important role in its invasion. However, we have little knowledge of its allelpathic effects on ferns. In Petri dish bioassays, the inhibitory potential of aqueous leachates from roots, stems and leaves of A. adenophora was studied on the spore germination and gametophyte development of Macrothelypteris torresiana. All leachates Inhibited the spore germination and growth of the first rhizoid of M. torresiana and inhibitory effects Increased with increasing leachate concentrations. Root leachates proved most inhibitory. Gametophyte rhizoids of M. torresiana treated with stem and leaf leachates ofA. adenophora were erect, which was similar to those of the control. However, gametophyte rhizoids of M. torresiana treated with root leachates of A. adenophora were erect, but also curving or swollen. Moreover, curving and swollen rhizoids Increased with Increasing concentrations. As time went by, rhizoids treated with root leachates were not so curved and the swelling almost disappeared. Possible causes are discussed in the present study. The increasing concentrations of leaf leachates also delayed the stages of gametophyte development. With the treatment of root leachates, the delay was more obvious. Thus A. adenophora inhibited the spore germination and gametophyte development of M. torresiana and the root leachates were most inhibitory.     

球腺肿足蕨的配子体发育特征及其系统学意义

采用改良Knop’s营养液液体和固体培养基,对球腺肿足蕨的孢子进行人工培养,利用光学显微镜观察其孢子的萌发及配子体发育过程。结果表明:成熟的孢子深褐色,不透明,极面观为椭圆形,赤道面观为豆形,单裂缝,周壁具密集的波纹状褶皱。孢子萌发类型为书带蕨型,原叶体发育类型为三叉蕨型。孢子接种后7d左右萌发,30d左右形成为片状体,50d左右发育为幼原叶体,幼原叶体不对称,但成熟原叶体心脏形对称。原叶体边缘及背腹面都具乳头状毛状体。75d左右精子器出现,精子器近圆球形,由3个细胞构成。90d左右颈卵器出现,成熟颈卵器颈部由4～5列细胞构成,3～5层细胞高。原叶体受精后1个月内可看到幼孢子体生成。最后讨论其系统学意义。     

Dry/wet cycling reduces spore germination and viability in six peatland bryophytes

• Dry/wet cycling driven by water level fluctuation in wetlands may strongly influence the destiny of seeds. However, how dry/wet cycling affects spore survival and germinability in peatland bryophytes is poorly understood.
• Six peatland bryophytes, three hummock- and three hollow-dwelling Sphagnum species, were chosen as study species. We tested the effects of dry (60% air RH)/wet (waterlogging) cycle frequency (once per 12, 8 or 4 days for low, medium or high, respectively) and ratio (3:1, 1:1 or 1:3 dry:wet time per cycle) on spore germinability, viability, dormancy percentage and protonema development.
• Dry/wet cycling significantly reduced spore germination percentage and viability and slowed protonema development in all Sphagnum species, being more pronounced with higher dry/wet cycling frequencies. The hummock species S. capillifolium and S. fuscum had higher spore germination percentage after the continuous dry treatment, while the hollow species S. angustifolium, S. squarrosum and S. subsecundum showed the opposite response, compared to the continuously wet treatment. Except for S. squarrosum, spore viability was higher after the dry than after the wet treatment. Spore viability and dormancy percentage were higher after a dry/wet ratio of 1:3 than after ratios of 3:1 and 1:1.
• Our study shows that both germinability and viability of bryophyte spores are reduced by dry/wet cycling (especially when frequent) in peatlands. This emphasizes the need to ensure constant water levels and low frequencies of water level fluctuation, which are relevant in connection with wetland restoration, to promote Sphagnum spore survival and establishment in peatlands after disturbances.

     

龙津蕨的配子体发育特征及其系统学意义

采用改良Knop's营养液液体培养基于25℃恒温培养箱中培养龙津蕨(Mesopteris tonkinensis)的孢子,每天光照12 h,黑暗12 h,光照强度为2 500 lx。用光学显微镜观察记录其孢子萌发、配子体发育的全过程,为龙津蕨系统学的研究提供配子体发育方面的详实资料。结果表明:成熟孢子深褐色,不透明,两侧对称,极面观椭圆形,赤道面观圆角三角形,具单裂缝,孢子周壁具密集的脊状褶皱。播种后15 d左右萌发,形成2~5个细胞长的丝状体。孢子萌发类型为书带蕨型(vittaria-type)。具单细胞假根,不含叶绿体,基部膨大。20 d左右发育成片状体,30 d左右形成幼原叶体,幼原叶体不对称,成熟原叶体心脏形对称,56 d左右形成成熟原叶体,原叶体发育类型为铁线蕨型(adiantum-type)。幼原叶体仅左右两翼顶端细胞产生乳突毛状体,成熟原叶体边缘及背腹面都具少量乳突毛状体,毛状体由单细胞构成。68 d左右精子器开始出现,精子器近圆球形,由基细胞、环细胞、盖细胞构成。75 d左右颈卵器出现,成熟颈卵器颈部由3层细胞构成。其侧面观柱状,顶面观为铜面状。颈卵器垂直于原叶体表或向原叶体基部倾斜。另外,根据已知的金星蕨科其他属的配子体发育特征,发现龙津蕨配子体发育的这些特征与他们存在较大的区别,因此龙津蕨系统学位置还有待于进一步研究。     

Possible involvement of Ca<Superscript>2+</Superscript>-dependent protein kinases in spore germination of the fern<Emphasis Type="Italic">Osmunda Japonica</Emphasis>

Fern gametophyte is a good model system to investigate signal transduction in plant cells. In this work, we examined whether CDPKs are involved in the mechanisms of spore germination of the fernOsmunda japonica. A protein extract from the spores included four CDPK isoforms with relative molecular weights of 56, 53, 49, and 47 kDa, as detected by immunoblot analysis, and they showed CDPK-like activities, as detected by in-gel protein-kinase assay. It was also found that the inhibitors effective on CDPKs, such as a general protein kinase inhibitor, K252a, and a calmodulin antagonist, W-7, largely suppressed the spore germination, and that many proteins of the spores were phosphorylated in vivo in a calcium dependent manner in the period when the spores require external Ca²⁺ for the germination. Furthermore, we showed that Sr²⁺ and Mn²⁺, which could substitute for Ca²⁺ in the spore germination, were also able to activate theOsmunda CDPKs. From these results, we concluded that CDPKs would participate in the spore germination ofO. japonica.