东北蕨类植物配子体发育的研究——Ⅰ.水龙骨科

蕨类植物具有两个独立生活的植物体世代,但研究工作常着重其孢子体世代,对配子体世代的了解往往被人忽视。Stokey和Momose自三十年代开始曾对蕨类配子体的形态学方面进行了研究,继之Atkinson尤其是Nayar等人系统地研究了同型孢子的真蕨类配子体的比较形态学及其在分类系统上的意义。蕨类配子体结构简单,生长周期短,易于观察,用来     

长江三角洲地区全新世蕨类孢子与藻类——以奉贤DY03钻孔的产出类型为例

长江三角洲奉贤DY03钻孔的全新统沉积物中蕨类孢子和藻类的种类丰富,如何正确鉴别,并解释它们的来源、传播与沉积过程等问题,成为讨论过去生物多样性变化、古生态环境与气候事件的重要基础.本文收录奉贤DY03钻孔沉积物中出现频率较高的蕨类孢子和藻类,蕨类孢子可能鉴定到种或属的水平,但也有部分种类只能鉴定到科的水平,有的类型难...     

蕨类植物孢子萌发及原叶体发育的观察

以腐叶土为培养基质,对21种蕨类植物进行了孢子萌发和原叶体发育的研究,结果表明：①不同时期播种的同种蕨类的孢子,发育出原叶体和幼孢子体所历经的时间长短不同;②孢子萌发和配子体生长发育的适宜温度约为15～24℃;⑨稀有蕨类的孢子萌发率低,而在野外能形成较大种群的蕨类的孢子萌发率高;④用GA3处理孢子可以促进萌发;⑤当原叶体上长出幼孢子体时,原叶体由大变小,由绿变黄,21种蕨类的原叶体都在幼孢子体上长出第3片叶时消失;⑥幼孢子体上长出的第1、2片叶在形态上与以后长出的叶不同;⑦孢子萌发需要光;⑧1片原叶体尽管有多个颈卵器,但仅发育出1株幼孢子体;⑨利用腐叶土进行蕨类孢子繁殖是一种经济实用的繁殖方法。     

野生浆果悬钩子营养成份分析

悬钩子(Rubus)广泛生长在山坡、沟旁和荒野间。果似草莓。体积约1.5厘米直径大小。味酸甜。成熟期在六月下旬至七月中旬之间。在我国分布的有几十种之多。为了开发和利用野生资源,我们在秦巴山区采集了4个不同种的悬钩子样品,对其营养成分进行了较系统的分析测定。     

甘肃窑街中侏罗世Coniopteris lanzhouensis的微细构造研究

本文对甘肃窑街中侏罗统窑街组采集的真蕨类化石标本进行了描述,通过与相似种的小羽片的形态和大小、羽片排列和间距、羽轴宽度、孢子囊群形态等特征对比,明确该化石植物为Coniopteris lanzhouensis。通过实验分析揭示了Coniopteris lanzhouensis的原位孢子基本特征:孢子为四面体,赤道轮廓呈圆三角形,顶角钝圆,三边线微凸或微凹;具三射线,三射线平直且较窄,长度为孢子半径的3/4或延伸至孢子边缘,顶端具与其垂直的褶皱;外壁光滑,壁薄,极面观直径30-40μm,平均约33μm;孢子的颜色以浅黄色为主。明确了Cibotiumspora juncta可能是Coniopteris lanzhouensis的孢子,后者为前者的母体植物。     

两种观赏蕨类植物的繁殖技术研究

探讨了江南星蕨和庐山石韦两种观赏蕨类的繁殖技术。分株繁殖主要在春季进行,并注意日常管理。两种蕨类的孢子繁殖采用5种基质对照,经试验,江南星蕨孢子繁殖的基质以泥炭土：蛭石：珍珠岩：2：1：1为最佳,而庐山石韦则以基质泥炭土：蛭石=2：1为最好。     

蕨类植物不同孢子裂缝类型在中国的分布格局

孢子在蕨类植物分类及有性生殖过程中具有重要地位, 一般都具有裂缝构造, 常见的是单裂缝和三裂缝, 极少数情况下有多裂缝的变异类型。我们统计了中国蕨类2,281种(含种下单位)的孢子裂缝类型, 来探讨两种不同裂缝类型的分布格局。结果表明: (1)具有单裂缝类型的物种数多于三裂缝类型, 单裂缝与三裂缝物种数目的比值(单/三比)与纬度和海拔呈正相关。随着温度下降以及降水量的降低, 具单裂缝孢子的物种比例增加。推测具单裂缝孢子的蕨类分布范围更广, 更适宜生活在干旱及高纬度或高海拔寒冷地区, 而具三裂缝孢子的蕨类更适宜存在于低纬度或低海拔的温暖地区; (2)蕨类植物孢子裂缝类型不是单次起源, 可能存在平行演化。本研究可以为蕨类植物的起源演化与生态适应等研究提供一定的证据。     

蕨类植物的无菌培养,快速繁殖和种质保存

我国有丰富的蕨类资源,共有2500种左右,占全世界1/6,其中有大量特有种.蕨类作为室内观赏植物,药用和蔬菜还没有得到充分的利用。另外随着森林和环境的破坏,有不少种已濒临灭绝.为了更好地开发和保存蕨类资源,我们进行了无菌培养的研究。成熟孢子经消毒无菌后在无激素的含活性碳培养基上可萌发形成原叶体,原叶体可以进行无性繁殖,在     

新疆准噶尔盆地白杨河中侏罗世植物化石新材料

系统描述了准噶尔盆地西北缘白杨河地区西山窑组植物化石15属25种,首次在新疆地区发现侏罗纪真蕨类重要分子Coniopteris hymenophylloides的原位孢子及其孢子囊群,并对Phoenicopsis ( Phoenicopsis) an-gustifolia的叶角质层进行了研究。白杨河地区西山窑组迄今已知植物化石24属39种,以富含蕨类、茨康类、银杏类及松柏类,少见苏铁类等为特征,属于较为典型的内陆型、温带或暖温带植物群;其时代为中侏罗世,且可能为中侏罗世早期。该植物群应属于欧亚大陆早、中侏罗世植物地理区系中的西伯利亚区,反映了温暖潮湿、具季节性变化、并有利成煤的环境。     

早泥盆世始叶蕨（新属）及叶子起源的讨论

本文报道了滇东南文山地区下泥盆统坡松冲组（西根阶）地层中一陆生植物新属,种－纤细始叶蕨（Eophyllophyton bellum gen.et sp.nov),植物体矮小,多次二叉分枝,远端枝二列互生长出次一级二叉分枝为主的末级枝,枝系起源叶顶生成侧生,多次分叉,缩合,扁化,蹼化并部分并合,生殖单位可下垂,由二枚顶端内卷的孢子叶组成,孢子囊圆至肾形,沿远,端加厚带开裂,成列侧生在孢子叶相对面的叶轴上,上述特征表明新植物远比同期的莱尼类,三枝蕨类和工蕨类复杂和进化,并显示出和工蕨类的某些亲缘关系,文内还探讨了枝系起源叶（大型叶）的发生和演化。     

瓶囊碘泡虫成熟孢子的显微及亚显微结构研究

应用光镜、透射电镜和扫描电镜观察,瓶囊碘泡虫Myxobolus ampullicapsulatus Zhao et al.,2008成熟孢子由孢壳、极囊和孢质3部分组成.其孢子壳面观呈梨形,缝面观呈凸透镜形,囊间突明显;2片孢壳厚而均匀且表面凹凸不平.极囊瓶形,位于孢子前端,约占整个孢子长度的2/3;极囊壁由"暗-明"2部分组成;极丝呈双"S"形缠绕并沿极囊纵轴逆时针向上螺旋8～11圈.孢质均匀而稠密,近球形的2个胚核大小不一;孢质中除了可观察到丰富的线粒体、粗面内质网、核糖体、高尔基体、嗜碘泡等细胞器及脂滴等泡状结构外,还可于孢质中观察到有一些数目不等的球状电子致密物质,其中2个分布于极囊周围.     

Growth and Dormancy in Lunularia cruciata (L.) Dum.: I. RESUMPTION OF GROWTH AND ITS CONTINUATION

Lunularia cruciata may become dormant at three stages in itslife history: mature thallus, gemma, and spore. The resumptionof growth and its continuation in various conditions have beenstudied in thalli and gemmae. Air-dry, mature thalli of theIsrael strain, planted on a suitable medium, produce adventitiousbranches ventrally from the region immediately posterior tothe existing meristem, which itself fails to resume growth.When dormant gemmae are taken from the gemma-cup, however, theexisting apical cells and meristems simply recommence growing,so that the new growth is continuous with the old. Except inthe case of mature thalli aroused from dormancy, apical dominanceis pronounced, and branching occurs only by bifurcation. Thisdominance can be broken by applying sucrose solution to thegrowing tips—possibly a plasmolytic effect. The growth in area of freshly planted gemmae accelerates forabout 25 days before its relative rate slows to any great extent.During the first half of this period, growth is due exclusivelyto the expansion of existing cells, but subsequently cell numbersincrease rapidly from the 8–10,000 present in the dormantgemma. Cell numbers were estimated by using a modified macerationtechnique, in which chelation followed prolonged fixation. Lunularia grows successfully at quite low light intensities.Of the mineral nutrient deficienccs investigated, lack of Plimits growth most severely, although N-deficiency also restrictsit to a very low level. Gemma-cup production appears to be unaffected by light intensity,at least within levels permitting growth. There is, however,a large temperature effect, cup production decreasing markedlyabove 12° C.     

山东省蕨类植物的区系分析

对山东省蕨类植物区系成分、地理分布和生态特点进行了初步研究,并与辽宁、日本等６个地区进行了比较。结果表明,山东省蕨类植物区系具有以下几个特点：１．区系成分不算丰富,但地理成分多样,以温带成分占优势,也残存有较多的热带成分;２．种系分化强烈,特有现象明显,特有种占１１．３％;３．地理分布极不均匀,并存在明显的地带性差异,表现为由南向北、由东向西种类减少;４．与辽宁、北京、河南关系密切,与秦岭、日本也     

Formation and composition of the Bacillus anthracis endospore

The endospores of Bacillus anthracis are the infectious particles of anthrax. Spores are dormant bacterial morphotypes able to withstand harsh environments for decades, which contributes to their ability to be formulated and dispersed as a biological weapon. We monitored gene expression in B. anthracis during growth and sporulation using full genome DNA microarrays and matched the results against a comprehensive analysis of the mature anthrax spore proteome. A large portion (approximately 36%) of the B. anthracis genome is regulated in a growth phase-dependent manner, and this regulation is marked by five distinct waves of gene expression as cells proceed from exponential growth through sporulation. The identities of more than 750 proteins present in the spore were determined by multidimensional chromatography and tandem mass spectrometry. Comparison of data sets revealed that while the genes responsible for assembly and maturation of the spore are tightly regulated in discrete stages, many of the components ultimately found in the spore are expressed throughout and even before sporulation, suggesting that gene expression during sporulation may be mainly related to the physical construction of the spore, rather than synthesis of eventual spore content. The spore also contains an assortment of specialized, but not obviously related, metabolic and protective proteins. These findings contribute to our understanding of spore formation and function and will be useful in the detection, prevention, and early treatment of anthrax. This study also highlights the complementary nature of genomic and proteomic analyses and the benefits of combining these approaches in a single study.     

Spore coat protein of Bacillus subtilis. Structure and precursor synthesis.

The coat protein of Bacillus subtilis spores comprises about 10% of the total dry weight of spores and 25% of the total spore protein. One protein with a molecular weight of 13,000 to 15,000 comprises a major portion of the spore coat. This mature spore coat protein has histidine at its NH2 terminus and is relatively rich in hydrophobic amino acids. Netropsin, and antibiotic which binds to A-T-rich regions of DNA and inhibits sporulation, but not growth, decreased the synthesis of this spore coat protein by 75%. A precursor spore coat protein with a molecular weight of 25,000 is made initially at t1 of sporulation and is converted to the mature spore coat protein with a molecular weight of 13,500 at t2 - t3. These data indicate that the spore coat protein gene is expressed very early in sporulation prior to the modifications of RNA polymerase which have been noted.     

THE EFFECTS OF CYCLIC AMP ON DIFFERENTIATION OF A MUTANT DICTYOSTELIUM DISCOIDEUM CAPABLE OF DEVELOPING WITHOUT MORPHOGENESIS

The dev 1510 mutant of Dictyostelium discoideum differs from the wild type in that unaggregated cells are capable of differentiating into either spores or stalk cells depending on the culture conditions (12). Taking advantage of this fact, the effects of cyclic AMP (cAMP) on differentiation of the mutant cells were examined under conditions that prevent normal morphogenesis. In the presence of low concentrations of exogenous cAMP, the cells differentiated into only stalk cells, whereas in the presence of high concentrations they differentiated into only spores. Untreated cells formed stalk cells, but this was inhibited by addition of phosphodiesterase, indicating that it was induced by a low concentration of cAMP which they produced themselves. Cyclic GMP and dibutyryl cAMP also induced spore formation though less effectively, while 5'AMP, ADP and ATP had no effect. During development, the cells increased in sensitivity to cAMP in that spore formation was induced at lower concentration of cAMP after 4 hr of starvation. Treatment of cells that had been starved for 6hr with 10⁻⁴M cAMP for as short a time as 30 min was enough to induce 8% of the cells to form spores.
The effects on cAMP-induced differentiation of chemicals that are known to influence development of the wild type were also examined. Both NH₄Cl and KCl inhibited cAMP-induced stalk formation, but had no effect on spore formation. In the presence of arginine, spore formation was induced at a lower concentration of cAMP with higher efficiency. CaCl₂, LiCl and KF had no effect on cAMP-induced differentiation.     

Fern-spore-feeder interaction in temperate forests in Japan: Sporing phenology and spore-feeding insect community

Angiosperms are widely appreciated to have flowering schedules, but far less attention has been paid to the timing of spore production by ferns. Although a range of abiotic factors are likely responsible for the timing of fern sporing, spore predation by specialist spore-feeding insects may also exert selective forces on timing. As a step toward understanding ecological factors that affect the evolution of fern sporing phenology, we tracked annual sporing patterns and examined associations with spore-feeding insects in 38 ferns species in two Japanese temperate forests. Most sporing occurred during June through August, the period of highest temperature and precipitation at the study sites, but some species produced spores during a limited period in spring or very late autumn. Over 70% of all species examined were attacked by spore-feeders, which consisted of seven polyphagous and five oligophagous species. Spore feeders occurred predominantly during June through September, and stathmopodid moth larvae consumed up to 70% of the mature sporangia. Thus, although the warm and humid conditions in the summer is likely favored for prothallial growth and fertilization, spring or late-autumn sporing in some species may have evolved as an adaptation to escape spore predation by spore feeders.     

罗汉果果实病害观察初报

经初步研究,罗汉果果实病害主要有炭疽病(Colletotrichum gloeosporioides(Penz) Sacc)、黑斑病(Alternara tenuis Ness)和腐烂病(Fusarium heterosporum Ness)3种,它们多见于成熟期前后。其中炭疽病为害期长,危害严重,在果实成长过程中,可用70％甲基托布津1000—1500倍液来防治。     

Fungal spore attachment to substrata

A critical factor in the success of fungal growth is spore adhesion to host surfaces. Generating spores capable of rapid and firm bonding to their hosts is not only important for keeping spores from prematurely detaching from the host surface but can also serve as a trigger for spore germination and the development of infection structures. In this paper fungal spore adhesion mechanisms are reviewed as well as factors influencing spore adhesion, germination, and differentiation. This review ends with a brief discussion on the future of fungal adhesion research.