短柄禾叶蕨配子体发育的研究

首次通过人工培养的方式,详细记录了短柄禾叶蕨（Grammitis dorsipila (Christ.)C.Chr.）具代表性的配子体形态发育全过程及各环节的特征,包括孢子萌发、原丝体、毛状体、叶绿体、边缘细胞、精子器等,并附特征性结构照片29幅。为禾叶蕨科（Grammitidaceae）的研究积累了配子体发育方面的详实资料,并初步讨论了短柄禾叶蕨配子体特征所体现的系统学意义。     

液体培养基条件下乌毛蕨配子体发育的研究

在液体培养基条件下对中国产乌毛蕨(Blechnum orientaleL.)配子体发育进行了观察。结果表明:乌毛蕨的孢子为两面体型,两侧对称,极面观为椭圆形,赤道面观为半圆形或豆形,周壁具脊状褶皱;孢子萌发为书带蕨型;原叶体发育为三叉蕨型,成熟原叶体为对称的心脏形。经比较分析,蕨类植物孢子繁殖时采用混合土培养较适宜;液体培养基和混合土在研究蕨类植物配子体发育时同样具有可行性。孢子形态和配子体发育的观察结果表明,乌毛蕨是蕨类植物中较进化的种类;乌毛蕨科与鳞毛蕨科亲缘关系较近。     

麦秆蹄盖蕨（Athyrium fallaciosum）配子体的发育规律及播种密度对配子体性别分化的影响

在组织培养条件下,对麦秆蹄盖蕨（Athyrium fallaciosum）配子体发育的连续过程进行了详细观察。结果表明:麦秆蹄盖蕨孢子为四面体型; 孢子萌发为书带蕨型（Vittaria-type）;原叶体发育为铁线蕨型（Adiantum-type）,成熟原叶体为对称的心形;精子器近圆球形,成熟颈卵器细长,常向原叶体基部倾斜或弯曲。常规播种条件下,发现麦秆蹄盖蕨配子体有雌配子体、雄配子体、雌雄同体配子体和无性配子体类型。配子体的性别随密度不同而呈现一定的变化趋势,雄配子体随密度增大呈上升趋势;雌配子体随密度增大先上升后下降;雌雄同体配子体和无性配子体随密度变化不大。雌配子体和雌雄同体配子体具颈卵器数目一般为10～15个;精子器数目随密度的增大逐渐减少,雄配子体中具有约50个精子器,雌雄同体配子体具有约20个精子器。     

香鳞毛蕨配子体发育的研究

研究了香鳞毛蕨(Dryopteris fragrans (L.)Schott)配子体的发育过程。结果发现孢子极面观为椭圆形,赤道面观为半圆形,单裂缝。孢子萌发为书带蕨型;丝状体2～9个细胞长,有明显顶端细胞,可形成多细胞的广阔板状片状体;片状体顶端分生组织继续分裂,发育为幼原叶体;原叶体发育为三叉蕨型;毛状体数量丰富,均为单细胞;颈卵器和精子器几乎同时形成,较小;成熟原叶体倒卵状心脏形。该配子体表现为进化性状。     

黑龙江省蹄盖蕨科(Athyriaceae)植物的RAPD分析及其系统学意义

在形态分类研究的基础上,利用RAPD技术,对黑龙江省蹄盖蕨科植物6属9种共15个种群进行了遗传多样性分析,分析结果表明：（1）假冷蕨属应包括在蹄盖蕨属中（2）角蕨属与蹄盖蕨属,羽节蕨属与冷蕨属亲源关系较近（3）短肠蕨属为独立一属,与其它属亲源关系较远。根据黑龙江省蹄盖蕨科植物的DNA水平的研究结果,再结合其形态学特征,建议将黑龙江省蹄盖蕨科划分为3个亚科：冷蕨亚科(Cystopterioideae)包括2个属：冷蕨属(Cystopteris)和羽节蕨属(Gymnocarpium)。蹄盖蕨亚科(Athyrioideae)包括3个属：蹄盖蕨属(Athyrium)、假冷蕨属(Pseudocystopteris)和角蕨属(Cornopteris)。双盖蕨亚科(Diplazioideae)包括短肠蕨属(Allantodia)。     

湖南蕨类植物区系新资料（Ⅱ）

报道了湖南蕨类植物区系新记录20种（隶属5科7属）;它们是毛足铁线蕨 (Adiantum bonatianum)、多芒复叶耳蕨（Arachniodes aristatissima）、狭长复叶耳蕨（A. attenuata）、粗裂复叶耳蕨(A. grossa)、南川复叶耳蕨(A. nanchuanensis)、黑鳞复叶耳蕨（A. ningrospinosa）、缩羽复叶耳蕨(A. reducta)、长刺复叶耳蕨（A. setifera）、节肢蕨（Arthromeris lehmannii）、多羽节肢蕨（A. mairei）、上斜刀羽耳蕨（Polystichum assurgentipinnum）、深裂耳蕨（P. incisopinnulum）、前原耳蕨（P. mayebarae）、假线鳞耳蕨（P. pseudosetosum）、边果耳蕨（P. shimurae）、钻鳞耳蕨（P. subulatum）、等基贯众（Cyrtomium aequibasis）、尖齿肋毛蕨（Ctenitis dentisora）、梵净肋毛蕨（C. wantsingshanica）、琼崖舌蕨（Elaphoglossum mcclurei）。     

狭眼凤尾蕨配子体发育及其成精子囊素对水蕨配子体发育的影响

对狭眼凤尾蕨（Pteris biaurita）配子体发育特征及其外源成精子囊素对模式植物水蕨（Ceratopteris thalictroides）在黑暗和光照条件下孢子萌发和配子体发育的影响进行了研究。结果表明：（1）狭眼凤尾蕨孢子深褐色,三裂缝,孢子萌发为书带蕨型,原叶体发育为水蕨型,无毛状体产生;培养发现,其配子体能产生精子器,但不产生颈卵器,当接种密度适中时,可进行无配子生殖。（2）在光照和黑暗条件下狭眼凤尾蕨成精子囊素有促进和抑制水蕨孢子萌发的作用,但效果均不显著。（3）在光照条件下,狭眼凤尾蕨成精子囊素可以延迟水蕨心脏形配子体分生组织缺刻的形成,但对其配子体形态和性别分化无明显影响;而在黑暗条件下狭眼凤尾蕨成精囊素对水蕨长条形配子体的形态发育具有一定影响,与对照组相比其顶端分生组织发达,整体呈长楔形,对性别分化影响不显著。可见,狭眼凤尾蕨和水蕨不具有同种成精子囊素系统。     

湖南蕨类植物区系新资料

报道了湖南蕨类植物区系新记录17种（隶属7科,11属）,它们是桫椤（Alsophila spinulosa）、长尾铁线蕨（Adiantunm diaphanum）半月形铁线蕨（A. philippense）、新月蕨（Pronephrium gymnopteridifrons）、密毛紫柄蕨（Pseudophegopteris hirtirachis）、禾秆紫柄蕨（P. microstegia）、金佛山溪边蕨（Stegnogramma jinfoshanensis）、假大羽铁角蕨（Asplenium pseudolaserpitiifolium）、都匀铁角蕨（A. toramanum）、长镰羽耳蕨（Polystichum falcatilobum）、瓦鳞耳蕨（P. fimbriatum）、棕鳞耳蕨（P. polyblepharum）、倒鳞耳蕨（P. retroso-paleaceum）、膜边肋毛蕨（Ctenitis clarkei）、三叉蕨（Tecaria subtriphylla）、指叶假瘤蕨（Phymatopteris dactylina）、掌叶线蕨（Colysis digitata）。     

黑轴凤丫蕨复合群的分类修订

凤丫蕨属(Coniogramme Fée)种间界限模糊,存在过渡类型,是蕨类植物中分类比较困难的类群之一。黑轴凤丫蕨(C.robusta(H.Christ) H.Christ)是凤丫蕨属植物中比较特殊的种类之一。本文在标本考证、野外考察和微形态研究的基础上对该种的分类进行了订正。将假黑轴凤丫蕨(C.pseudorobusta Ching et Shing)和新黑轴凤丫蕨(C.neorobusta Ching et Shing)归并到黑轴凤丫蕨。同时对该种下的两个变种黄轴凤丫蕨(C.robusta var. splendens Ching et Shing)和棕轴凤丫蕨(C.robusta var. rependula Ching et Shing)重新定义模式标本。     

骨碎补铁角蕨（铁角蕨科）——海南岛一新分布种

报导了海南岛铁角蕨科一新分布种,即骨碎补铁角蕨(Asplenium ritoense Hayata)。在国内的植物志采用的学名是一不合法名称,即Asplenium davallioides Hook.。应给予纠正。     

Microsatellite DNA Variation of the Gametophyte Clones Isolated from Introduced Laminaria japonica （Phaeophyta） and L. Iongissima of China and Varieties Derived from them

The variation of 90 Laminaria gametophyte clones representing the introduced Laminaria japonica （Group 1） and Laminaria Iongissima （Group 2）, the varieties of L. japonica （Group 3） and the varieties derived from interspecific hybrids （Group 4） was determined with 18 microsatellite markers. The allelic diversity and Nei＇s gene diversity of Group 1 were significantly higher than those of Group 2 （2.9 vs. 1.8 and 0.414 vs. 0.161, respectively）, demonstrating that the variation of the introduced L. japonica is richer than that of L. Iongissima. Both allelic diversity and Nei＇s gene diversity of Group 3 were lower than those of Group 1, indicating that only a portion of variation of L. japonica was incorporated into the varieties of L. japonica. Significant genetic differentiation was detected between four groups and between female （Population 1 ） and male （Population 2） gametophyte clones in each group. The variation among groups accounted for 39.95%, while that among populations accounted for 21.65% of the total. The genetic distance between Group 1 and Group 4 was obviously longer than that between Group 2 and Group 4 （0.686 vs. 0.291）, indicating that maternal gametophyte clone contributed more variation to the hybrids than the paternal gametophyte clone did.     

Reproductive Biology of the Pteridophyta

Because of the homothallic nature of many pteridophytes, two categories of mating are possible: intragametophytic selling (the origin of both gametes from a single gametophyte) and inter-gametophytic mating (the origin of each gamete from a different gametophyte).Various morphological and genetical criteria (placement of the gametangia on the thallus, their sequence of ontogeny, the capacity for simple polyembryony and genetic self-incompatibility) can be used to indicate the relative probability of intragametophytic selfing or intergametophytic mating. Only the former has genetic significance (i.e.complete homozygosity); if the latter is evidenced, then detailed studies of population variability are required to ascertain the breeding system.
Three types of reproductive systems involve the gametophyte generation: intragametophytic selfing, intergametophytic mating and apogamy. Apogamy generally offers the shortest gametophyte generation and the least evolutionary potential, intergametophytic mating systems generally have the longest gametophyte generation and the greatest evolutionary potential, and intragametophytic mating systems are intermediate in both respectS. It is envisioned that the interaction between gametophyte ecology and evolutionary potential is important in the evolution of a taxon's reproductive system.     

Reproductive biology of the Pteridophyta. II. Theoretical considerations

Because of the homothallic nature of many pteridophytes, two categories of mating are possible: intragametophytic selling (the origin of both gametes from a single gametophyte) and inter-gametophytic mating (the origin of each gamete from a different gametophyte).Various morphological and genetical criteria (placement of the gametangia on the thallus, their sequence of ontogeny, the capacity for simple polyembryony and genetic self-incompatibility) can be used to indicate the relative probability of intragametophytic selfing or intergametophytic mating. Only the former has genetic significance (i.e.complete homozygosity); if the latter is evidenced, then detailed studies of population variability are required to ascertain the breeding system. Three types of reproductive systems involve the gametophyte generation: intragametophytic selfing, intergametophytic mating and apogamy. Apogamy generally offers the shortest gametophyte generation and the least evolutionary potential, intergametophytic mating systems generally have the longest gametophyte generation and the greatest evolutionary potential, and intragametophytic mating systems are intermediate in both respectS. It is envisioned that the interaction between gametophyte ecology and evolutionary potential is important in the evolution of a taxon's reproductive system.     

RELATIONSHIP BETWEEN MALE AND FEMALE GAMETOPHYTE DEVELOPMENT IN RYE

The development of male gametophyte and female gametophyte within a floret of rye (Secale cereale L.) was examined. Generally, meiosis in microsporocytes and in megasporocytes occurs simultaneously in most florets, but the period from zygotene to tetrad meiosis in the megasporocyte progresses more slowly than that in the microsporocyte. When the female gametophyte has one nucleus and no vacuoles, the male gametophyte has a single, eccentric nucleus. By the time the female gametophyte develops to the vacuolated one-, two-, four-, and eight-nucleate stages and to the growth and differentiation of the egg apparatus stage, the male gametophyte reaches the two-celled pollen stage. As the female gametophyte matures, the male gametophyte also reaches maturity. The duration of male gametophyte development from microspore mother cell and the duration of female gametophyte development from megaspore mother cell are the same in most florets. The relationship between sexual development of cross-pollinated rye is similar to that of self-pollinated wheat (Triticum aestivum L.). It seems that the relationship is not related to the breeding system.     

不同环境因子对珍稀观赏蕨类金毛狗配子体性别分化的影响

金毛狗[Cibotium barometz(L.)J.Sm.]是珍稀观赏蕨类的重要类群,为国家二级重点保护野生植物。该研究以金毛狗孢子为试验材料,探究培养密度、外源赤霉素以及光质等不同环境因子对金毛狗配子体性别分化的影响,为金毛狗人工繁育和蕨类植物配子体性别决定机制研究提供技术支持。结果表明:(1)低配子体培养密度(1个/cm2和5个/cm2)有利于颈卵器和雌配子体形成,随着配子体培养密度增加,颈卵器平均数量及雌配子体比率下降,精子器平均数量以及雄配子体和两性配子体比例增加,但配子体培养密度过高(80个/cm2)会导致大量无性配子体产生。(2)不同配子体培养密度下,随着培养时间延长,两性配子体比率均有增加,且增加幅度基本一致。(3)外源GA4显著抑制颈卵器和雌配子体形成,并显著促进精子器和雄配子体形成;外源GA3对金毛狗配子体性别分化没有显著影响。(4)白光、红光、蓝光等不同光质对金毛狗配子体性别分化未产生显著影响,但会影响配子体的发育和形态建成。     

Oleosins in the gametophytes of Pinus and Brassica and their phylogenetic relationship with those in the sporophytes of various species

Oleosins, which are structural proteins on the surface of intracellular oil bodies, have been found in the sporophytic seeds of angiosperms. Here, we report an oleosin from the female gametophyte of gymnosperm Pinus ponderosa Laws, seed and another oleosin from the male gametophyte of Brassica napus L. With the pine seed gametophyte, we identified two putative oleosins of 15 and 10 kDa, which are similar to the oleosins in angiosperm seeds in terms of their presence in the oil bodies in massive quantity. The complete sequence of the cDNA encoding the gametophytic 15-kDa oleosin was obtained, and it has a predicted amino-acid sequence similar to those of oleosins in angiosperm sporophytic seeds. A Brassica napus pollen cDNA sequence, which was reported earlier, would encode an amino-acid sequence somewhat similar to those of seed oleosins. We tested if the dissimilarity signifies a substantially different oleosin in the Brassica male gametophyte or an analytic error. By direct sequencing of a polymerase chain reaction (PCR)-amplified fragment of genomic DNA, we obtained evidence showing that this reported dissimilarity is likely to have arisen from a sequencing error. Our predicted sequence of the Brassica pollen oleosin has all the structural characteristics of seed oleosins. A phylogenic tree of 20 oleosins, including those from sporophytic and gametophytic tissues of angiosperm and gymnosperm, was constructed based on their amino-acid sequences. We discuss the evolution of oleosins, and conclude that oleosins are ancient proteins with multiple lineages whose root cannot be determined at this time.Abbreviations PCR polymerase chain reaction - TAG triacylglycerols This work was supported by USDA grant 91-01439 (AHCH). We thank Dr. Mike Lassner of Calgene, Inc., (Davis, Calif., USA) for providing us with the unpublished jojoba oleosin amino acid sequence.     

Phytochrome-mediated germination and early development in spores of Dryopteris filix-mas L.: phase-specific and non phase-specific inhibition by staurosporine

The alkaloid staurosporine, currently known as the most potent inhibitor of protein kinase C, PKC, was tested for its ability to inhibit phytochrome-mediated spore germination in Dryopteris filix-mas L., evaluated by the induction of chlorophyll synthesis. Approximately half-maximal inhibition was obtained at a concentration of 10(-5) M. This effect of staurosporine was phase-specific and was found during the same period in which the presence of extracellular calcium is necessary for realization of the light signal. Furthermore, the ability of staurosporine to prevent progression of a germinated spore into early gametophyte development, evaluated by the accumulation of chlorophyll, was examined. Again, staurosporine (10(-5) M) significantly diminished chlorophyll accumulation, determined quantitatively in vivo by single-cell measurements, in a non-phase specific way. The fact that the phase-specific inhibitory effect of staurosporine in preventing germination was coincident with the phase-specific requirement of Ca2+ suggests that both Ca2+ and staurosporine affect the same step in the signal-transduction chain. A phosphorylation event catalysed by PKC or any Ca2+ -dependent protein kinase is proposed as the target of staurosporine and Ca2+.