中国团藻科新记录属—— 板藻属(Platydorina)

在广东省深圳水库采集的浮游植物样品中发现团藻科1个单种属及其种：板藻属（Platydorina）、具尾板藻（Platydorina caudata Kofoid）。植物体扁平状马蹄形,微呈左旋;在马蹄形后端具3至5个胶质突起;由16或32个细胞在胶质基质中朝不同的方向排列成单层的群体,细胞球形或梨形,具2条等长鞭毛,细胞在群体两面交错排列;每个细胞具1个眼点;鞭毛基部具2个伸缩泡;色素体大型杯状,1个蛋白核位于杯状色素体的基部。无性繁殖通过亲体部分或全部细胞的反复分裂完成;有性生殖为异配生殖,形成厚壁休眠合子。     

月绿藻属一新种(团藻目)——饶氏月绿藻

根据饶钦止教授生前手稿记录及图认定饶氏记载的是月绿藻属1新种,命名为饶氏月绿藻(Selenochlorisjaoii):细胞侧扁,正面观卵形,后端裂成两瓣,钝圆,无乳头状突起;侧面观卵形,后端钝圆;2条等长的鞭毛从细胞顶端伸出,长度为细胞长的1.5倍;色素体杯状,无蛋白核,具1个大的细胞核。细胞长10.5~12μm,宽8.75μm,厚6μm。本种与S.reniform is(P layfair)Ettl近似,但后者细胞正面观为肾形,与前者明显不同。     

中国苔类植物一新记录属——假带叶苔属

在研究安徽苔藓植物区系过程中,发现一中肋部分具双输导束的假带叶苔属植物。这是一个单种属,原仅在日本有过报道,故为我国新记录,现报道如下。 假带叶苔属 Hattorianthus Schust. & Inoue, Bull. Natn. Sei. Mus. Tokyo, Ser. B. (Bot.) 1 (3): 1 (3): 103, 1975. 植物体黄绿色,基部及中肋部分黄褐色;叶状体,基部柄状,直立或倾斜生长,宽4—7mm,长20—35mm,边缘略波曲;中肋部分上平下凸,横切面高15—17细胞,具     

中国淡水绿藻纲新记录属麦可属(Mychonastes)

从我国滇池分离、培养获得2株超微真核藻, 对其进行形态学、细胞超微结构和18S rRNA基因序列分析。结果表明: 藻株在细胞形态、结构和繁殖方式具麦可属(Mychonastes Simpson Van Valkenburg)特征, 细胞壁2层, 外层细胞壁表面具不规则肋网和典型的暗-明-暗结构; 具备一套简单的细胞器, 包括细胞核、不具蛋白核的叶绿体和线粒体各1个, 叶绿体周生、杯状, 占据细胞大部分体积; 以似亲孢子方式繁殖。结合18S rRNA序列分析, 将其归为麦可属, 属于绿藻纲、绿藻门, 是该属在我国淡水湖泊的首次描述。       

海南岛木耳属的研究

子实体单生,鲜时坚韧的胶质,不透光,耳状,1-2×2.5-3.5cm,厚2-3.1mm,基部发达,呈黄褐色,不孕面有短柔毛和许多短的裂缝,栗褐色,干时棕黑色;子实层有粗条状隆起密集的结节,紫红色,干后紫黑色。柔毛层:毛长30-80(-100)μm,粗4-5.5μm,无色到褐黄色,不成簇,具狭窄的腔,顶园,易截断,基部明显膨大或再突然收缩成细而长的根状;致密层:20-50μm     

形形色色的藻类植物

图1-2 甲藻门 1.Gymnodinium eucyanochroum扫描电镜照片。示细胞的横沟和纵沟中各有1条鞭毛;2.角甲藻Ceratiumhirundinella背面观,示横沟、1个顶角和3个底角,淡水产。图3金藻门锥囊藻属Dinobryon树状群体,每个细胞外均有1个钟罩状的囊壳。生活于清洁的淡水中。图4-7硅藻门(细胞均经过酸化处理,示壳面花纹) 4.蛇目圆筛藻Coscinodiscus argus壳面圆形,具六角形孔纹,呈放射状和螺旋状排列。海产。     

云南金合欢属一新记录种

<正> 双腺金合欢 新记录 图1 Acacia tonkinensis Ⅰ. Nielsen in Adansonia sor. 2, 19(3): 358. 1980. 灌木攀援,有倒钩状小刺;小枝,叶柄,花序梗,叶轴和花序轴密被锈色茸毛。托叶卵形早落;二回羽状复叶,叶轴下面有倒刺;总叶柄具倒刺,基部和中部以上各具1个小腺体,以及最顶上1—3对羽片之间具有1个小腺体,小腺体圆锥形或瘤状;羽片9—12对,     

假橐吾属, 中国菊科植物一新属

多年生草本,根状茎粗短,有多数纤维状根,茎基部有残存的叶柄。叶互生、纸质,基生叶在花期宿存,具长叶柄,长圆状心形或宽卵状心形,楔状下延成具翅的叶柄,基部扩大,半抱茎,但绝无叶鞘;中部茎叶与下部叶同形,较小,具短叶柄,叶柄具翅,自中部向基部逐渐扩大,基部具叶状卵形抱茎的叶耳。头状花序盘状,在茎端排列成总状;花序梗有2枚小     

中国藓类植物新记录属—筛齿藓属

作者在芬兰赫尔辛基大学植物标本馆(H)研究Dr.T.Koponen 1970年在台湾采集的部份苔藓标本时,发现了筛齿藓(Coscinodon cribrosus (Hedw.) Spruce)。筛齿藓属(Coscinodon Spreng)为中国植物新记录属,特此报道。筛齿藓的主要区别特征为:(1)植物体矮小,呈丛生垫状,叶先端具透明毛尖;(2)叶披针形,中肋两侧具明显长纵褶;(3)叶基部细胞长形至长方形,薄壁;(4)蒴柄短,孢蒴内隐于孢叶之中;(5)蒴帽大,钟形,具纵褶,覆盖大部孢蒴;(6)蒴齿具筛孔。     

广东省淡水红藻弯枝藻属一种（Compsopogon sp．）的形态描述及分类地位探讨

2009年8月在广东省龙川县定南水河采集到一份弯枝藻属的标本,其形态特征介于弯枝藻（Compsopogon caeruleus）和疏枝弯枝藻（Csparsus）之间。植物体株高10～18cm,主轴直径180～270μm,微收缢;中轴细胞近球形和扁球形,横壁收缢明显,直径150-200μm,高100～110μm;皮层细胞1层,中轴细胞缢缩处为2—3层;多角形或卵形,长25~35μm,直径20-25μm;分枝直出至侧生,某些基部细胞特化为假根;分枝顶端渐尖、急尖或二叉状;单孢子球形,直径10—14μm。该标本可能为弯枝藻和疏枝弯枝藻在演化过程中的一种过渡类型。     

Isolation and some properties of extracellular glucan-producing strains of human oral Streptococcus salivarius

A total of eighteen strains of Streptococcus salivarius, which formed rough gelatinous, rough mucoid or smooth mucoid colonies on sucrose agar media, were isolated from the saliva and tongue dorsum of adults. All of the isolates produced glucans as well as fructans from sucrose. The bulk of the glucans was synthesized by the extracellular enzyme fraction and was water insoluble, whereas most of the fructans were synthesized by the cell-associated enzyme fraction and were water soluble. All strains formed microbial deposits on wire and glass surfaces when cultured in sucrose broth, but their sucrose-dependent adhesion was apparently looser than that produced by a cariogenic S. sobrinus strain. The rough gelatinous colony forming strains possessed a greater ability to synthesize water-insoluble glucans and produced heavier deposits with higher cohesion. Preliminary studies showed that the S. salivarius of such characteristic forms of colony were detected primarily in the saliva and tongue dorsum: the smooth mucoid colony formers appeared to predominate in the tongue coat and the rough mucoid and rough gelatinous colony formers were prominent in saliva. Isolation of these S. salivarius from dental plaques was low.     

Sexual reproduction inEudorina elegans (chlorophyta,volvocales)

Sexual reproduction inEudorina elegans Ehr. was studied in detail in laboratory cultures, with particular regard to conjugation between gametes and gone colony formation. Male and female gametes fused after being induced by changing the medium. The anterior end, including the flagellar base, of the male gamete entered the anterior region of the female gamete. Fusion of the two protoplasts proceeded laterally and posteriorly. The male gamete bore a slender cytoplasmic protrusion at the base of the flagella. This structure has not been previously described in the male gamete ofEudorina, and may participate in plasmogamy. A biflagellate gone cell swam from the germinating zygote and secreted a gelatinous envelope. It then divided to form a gone colony within the gelatious envelope, which moved during colony formation by means of the two flagella which were retained intact from the original gone cell.     

三峡库区消涨带特有濒危植物丰都车前Plantago fengdouensis的迁地保护

丰都车前(Plantago fengdouensis)为近年在三峡库区消涨带发现的一特有植物。通过多年的调查,发现该种仅分布于重庆市忠县、丰都县和巴南区等3个长江江心岛上,总共290株。随着三峡水库的逐步蓄水,丰都车前的自然分布区将于2006年全部水淹,使其成为因三峡工程建设而导致自然生境和野生居群全部毁灭的唯一的草本植物。为保护这一即将野外灭绝的稀有植物,在对其地理分布、生态学和群落学调查的基础上,对其形态特征、年生长周期和生殖值与同属植物车前(P.asiatica)和北美车前(P.virginica)进行了调查、试验和比较研究,表明丰都车前果期长、种子不适宜长距离传播和生殖值低以及长江水淹干扰是其狭域分布和数量稀少的主要原因。同时探讨了其迁地保护策略,并提出了下一步的研究和保护建议。     

GLOEOCOCCUS TETIMSPORUS SP. NOV. (TETRASPORALES,PALM ELL ACEAE), FROM COLORADO MOUNTAIN LAKES1

A new species, Gloeococcus tetrasporus sp. nov., collected from mountain lakes, is described from unialgal culture. Vegetative cells are ellipsoid and Chlamydomo nas–like, occur in tetrad complexes within the general colonial matrix, and exhibit slow, limited motility within the confines of the individual gelatinous matrices. The colonial matrix is amorphous and structureless, without a definite bounding layer. Colonies may reach several centimeters in size. Vegetative cells have a parietal cup–shaped chloroplast with a central–basal pyrenoid and a small, linear stigma, two contractile vacuoles, and two short flagella. Cell division is by eleutheroschisis in nonflagellate cells. After two divisions, four daughter cells arc formed within the expanded parent wall that will become incorporated into the colonial matrix. Zoospores are formed either from transformed vegetative cells or after cytokinesis. Zoospore flagella are two to three times the length of vegetative cell flagella. Rapid flagellar movement ruptures the sheath and liberates the zoospores. When zoospores settle, they secrete new sheaths, and divide twice to initiate new colonies. Sexual reproduction and formation of resistant spores were not observed.     

阿维菌素和哒螨灵亚致死剂量对土耳其斯坦叶螨实验种群生命表的影响

为了了解阿维菌素和哒螨灵对土耳其斯坦叶螨Tetranychus turkestani Ugarov et Nikolski实验种群的亚致死效应, 为新疆土耳其斯坦叶螨的综合防治提供理论依据, 我们在室内通过叶碟饲养的方法, 利用生命表技术研究了阿维菌素和哒螨灵亚致死剂量对土耳其斯坦叶螨实验种群成螨和卵的影响。结果表明: 阿维菌素和哒螨灵LC₂₀、LC₁₀剂量处理成螨后, 可使成螨的产卵量、平均寿命和卵孵化率显著降低; 卵期、幼螨期、若螨期和产卵前期明显延长, 而成螨期和雌螨寿命又明显低于对照; 对次代种群的影响表现在净生殖率(R₀)、 周限增长率(λ)降低、生存率和平均每雌日产卵率明显降低, 内禀增长率（r_m）由0.37降低至0.17～0.29, 平均世代历期(T)除阿维菌素LC₂₀处理时长于对照外, 其他处理均低于对照, 种群倍增时间(Dt)延长。两种药剂亚致死剂量处理卵后, 内禀增长率（r_m）由0.32降低至0.11～0.22, 净生殖率(R₀)降低, 平均世代历期(T)和周限增长率(λ)降低, 而种群加倍时间(Dt)增长; 幼螨期、若螨期和产卵前期明显长于对照, 成螨期和雌螨寿命显著低于对照; 生存率和平均每雌日产雌率明显降低。这些结果证明, 在亚致死剂量下, 阿维菌素和哒螨灵能够降低土耳其斯坦叶螨种群的发育速率, 这对土耳其斯坦叶螨的综合防治策略的制定有积极意义。     

鱼腥藻PCC7120基因all5292和alr0647的初步研究

通过BLAST软件分别对藻胆蛋白裂合酶(biliprotein lyase)编码基因cpcS和cpcT进行同源搜索分析,在鱼腥藻(Anabaena)PCC7120中获取了同源基因all5292和alr0647。同源分析发现,这两个基因所编码氨基酸序列与其相对应的裂合酶氨基酸序列相似程度分别达到53.4%和61.4%。随后,对这两个基因进行了初步研究。结果显示:All5292和Alr0647无论单独还是共同表达均没有裂合酶催化藻蓝胆素PCB结合到藻蓝蛋白(phycocyanin)或藻红蓝蛋白(phycoerythrocyanin)β亚基上的功能。通过在不同生理条件下对鱼腥藻PCC7120的培养,还对这两个基因的调控表达进行了初步的探索。结果表明:all5292和alr0647的表达与氮源的缺乏与否有联系,在氮胁迫条件下两个基因均进行了转录而在氮源充足的情况下则没有表达。     

Karyotypes of thirteen species of Iris L. from China

Cytological studies were carried out for 13 taxa in the genus Iris from China, of which three species, namely I. subdichotoma, I. delavayi and I. cuniculiformis were endemic to China. The chromosome numbers in somatic cells for each taxon were as follows: I. subdichotoma, 2n=42; I. japonica, 2n=34; I. wattii, 2n=30; I. laevigata, 2n=32; I. ruthenica var. nana, 2n=42; I. collettii, 2n=28; I. dolichosiphon and I. cuniculiformis, 2n=22; I. bulleyana, I. delavayi, I. chrysographes, I. forrestii, and I. lactea var. chinensis, 2n=40. The chromosome number and karyotype of I. cuniculiformis were reported here for the first time and its karyotype formula was 2n=22=4m+6sm+12st(2SAT). The karyotype of I. dolichosiphon was also firstly reported, whose karyotype formula was 2n=22=4m+12sm+6st. The chromosome number and karyotype of I. subdichotoma was newly observed, whose karyotype formula was 2n=42=20m+22sm. Three populations of I. ruthenica var. nana from different localities were investigated and all the three populations had the same chromosome numbers different than previously reported. The karyotype formulae for I. ruthenica var. nana were shown as follows: Zhongdian population, 2n=42=30m+12sm (2SAT); Lijiang population, 2n=42=28m+14sm(2SAT); Nixi population, 2n=42=36m+6sm (4SAT). In addition, the 2n chromosome numbers of three subgenera Limniris, Iris and Nepalensis in the genus Iris from present results and previous reports were summarized. The results showed that the chromosome number varied considerably in subgen. Nepalensis, in which I. subdichotoma was possibly a key species between the genus Pardanthopsis and subgen. Nepalensis. Chromosome number of I. ruthenica was reported as 2n=84 which was twice as much as its variety I. ruthenica var. nana (2n=42) we observed. By comparing with related groups, I. ruthenica is likely to derive from diploid group. Finally, variation of chromosome number and evolutional tendency of karyotype in the genus Iris were also discussed.     

富营养底质对沉水植物的胁迫研究 Ι.乙酸对伊乐藻和菹草萌发与幼芽生长的影响

湖泊底质中有机物的厌氧代谢产生多种有机酸,其中主要成分是乙酸。研究了暴露于不同浓度的乙酸溶液后伊乐藻(Elodea nuttallii)和菹草(Potamogeton crispus)无性繁殖体的萌发和幼芽的生长状况。1 mmol/L的乙酸能显著抑制伊乐藻幼芽的生长(p<0.05),但对其繁殖体的萌发无明显影响。在4 mmol/L的乙酸影响下,菹草幼芽仍有明显的生长;菹草繁殖体的萌发受到显著抑制(p<0.05),但在随后的培养中可全部萌发。4 mmol/L以上的乙酸暴露3 d或6 d导致伊乐藻全部死亡,8 mmol/L的乙酸处理6 d或16 mmol/L的乙酸处理3 d或6 d导致菹草全部死亡。研究表明厌氧底质中的乙酸可能是阻碍沉水植物生长的重要因素之一,菹草比伊乐藻能耐受较高强度的乙酸胁迫,更适合作为先锋物种用于富营养化湖泊中的沉水植物恢复。     

Colonial development in Pandorina morum. I. Structure and composition of the extracellular matrix

Every cell in a colony of the freshwater alga Pandorina morum produces a daughter colony in each round of vegetative reproduction. The cells of P. morum structurally resemble those of Chlamydomonas and do not obviously differ from their presumptive unicellular ancestor in ways that would account for their colonial state. It is therefore possible that their colonial association may be the result of altered extracellular matrix, intercellular connections, or modified processes of cell division and matrix formation. The ultrastructural studies and chemical analysis reported here show that the matrix of P. morum is a multilayered structure containing hydroxyproline-rich glycoproteins and sulfated polysaccharide. Significantly, this matrix displays no major differences from the “wall” of Chlamydomonas species. No intercellular connections have been found in mature colonies. The extracellular matrix therefore maintains, but does not initiate, the colonial arrangement of the cells.