星叶草下胚轴解剖

星叶草的茎部很短,下胚轴的长度几乎占有植株的整个高度。纤细的下胚轴主要依靠表皮层细胞外壁角质膜的增厚,以及中央初生木质部束的支持。初生木质部与初生韧皮部之间可见到2—3层排列规则或不规则的薄壁组织细胞,但是没有维管形成层的发生。这种植物的根茎维管组织的过渡区域,看不到一般双子叶植物中所见到的初生木质部束扭曲、分开或倒转的现象。伸向子叶的子叶迹,直接由原生木质部极外面的一群薄壁组织细胞分化形成。第一和第二片叶子的叶迹则在初生韧皮部中间发生。     

Morphological Studies on Circaeaster agrestis Maxim. (1) Process of Embryolo gical Development

The present paper aims at discovering the characters of embryological development of Circaeaster agrestis, which makes up a monotypic genus, Circaeaster, to establish the phylogenetic relationships of the genus. The different opinions on its systematic position among botanists are briefly explained. The embryological studies show that the most important advanced characters of the genus are as follows. The ovule is amphitropous, unitegmic and tenuinucelar; the embryo sac formation is in accordance with the Polygonum type; endosperm formation is of the cellular type, the primary endosperm nucleus dividing to form two cells and the first wall vertical; embryo formation follows the variation of the Caryophyllad type; at the early stage of development of embryo, the integument has been already atrophied and at last disappeared, so that the seed coat is absent in the mature fruit. On the basis of the embryological and some morphological evidence, the authors consider that a close relationship between the genus and Ranunculaceae and its related families seems to be unlikely. The affinities of the genus Circaeaster are still uncertain.     

基于形态学资料星叶草属系统位置的探讨

基于以往的形态学研究资料,对星叶草属与毛茛目其它成员进行了比较。结果表明,该属在一些基本的或原始的性状上与其它毛茛目成员相似,特别是它与毛茛科一些植物幼苗问的相似性表明,这个属应该属于毛茛目的成员,而且有可能通过幼态成熟的方式起源于前毛茛目植物。星叶草属与其它毛茛目成员问的区别,尤其是在维管系统和胚胎发育方面的区别表明,星叶草属在毛茛目内发生以后,可能是沿着一条特化和减化的途径发展的。     

播娘蒿下胚轴高频率再生植株因素的研究

以播娘蒿（Descurainia sophia)下胚轴为外植体,研究影响其分化的若干因素。结果表明：用附加2,4－D的培养基,对下胚轴切段预培养5d可提高分化频率;1.7mg/L AgNO3对分化出芽有很大促进作用,最佳激素组合为2.0mg/L 6-BA 0.2mg/L NAA;黄化苗的下胚轴比绿苗的下胚轴对激素反应更敏感,最高分化频率可达86.05%。再生芽转至1／2MS 0.5mg/L NAA 0.5mg/L IBA的培养基中,生根率100％。     

星叶草叶脉序的形态学及其系统学意义

在星叶草叶二叉分枝脉序中,网结脉中2条完全汇合叶脉与靠近脉中完全分离叶脉间未发现任 何形式的维管束汇合的中间类型,相反观察到了网结脉中不同程度的连接脉退化的痕迹,因此网结脉不可能由靠近脉形成;盲脉的出现与齿的退化、网结脉中连接脉的间断及非网结脉由分枝处间断等相关;上述事实表明星叶草叶的二叉分枝脉序应为一减化性状。     

Number of floral organs in Circaeaster agrestis (Circaeasteraceae) and possible homeosis among floral organs

98.9% of 5092 flowers from 1041 individuals of Circaeaster agrestis have five floral organs, the formula is P₃A₁G₁ (73.13%), P₂A₂G₁ (25.59%), and P₂A₁G₂ (0.22%). Only 0.4% of the flowers have six floral organs and the formula is P₃A₁G₂ (20 flowers) or P₃A₂G₁ (one flower). All these flowers have one vascular bundle in the pedicel and were considered to be normal ones. There are 33 flowers (0.65%) with six or more floral organs and two vascular bundles in the pedicel and we found traces of fusion of different degree of two flowers into one. These flowers were considered as abnormal. Therefore the normal number of floral organs of C. agrestis is five and occasionally six, and the floral formulas are P₃A₁G₁ or P₂A₂G₁, sometimes P₂A₁G₂, and occasionally P₃A₁G₂ or P₃A₂G₁. A tepal in P₃A₁G₁ may be replaced by a stamen in P₂A₂G₁ or by a carpel in P₂A₁G₂ or in reverse. A carpel in P₃A₁G₂ may be replaced by a stamen in P₃A₂G₁ or in reverse. We hypothesize that there are two possibilities for the number of the floral organs to be five (six), the result of reduction from P₃A₂G₂, or there exists homeosis among floral organs.     

金鱼草下胚轴不同部位切段形态发生能力的研究

金鱼草（ＡｎｔｉｒｈｉｎｕｍｍａｊｕｓＬ．）下胚轴不同部位切段的形态发生能力有很大差异。在外源添加ＢＡ,ＮＡＡ的情况下,金鱼草下胚轴近基部切段培养物的芽、根发生明显高于其上各部位切段,以近基部切段为外植体培养时,其形态发生能力以ＢＡ和ＮＡＡ配合为好,最适剂量为ＢＡ１０ｍｇ／Ｌ＋ＮＡＡ０１５ｍｇ／Ｌ。     

UVB诱导的绿豆下胚轴原生质体收缩效应

ＵＶ－Ｂ处理外起绿豆幼苗下胚轴原生质体的收缩;绿豆幼苗的下胚轴的伸长亦受ＵＶ－Ｂ处理的显著抑制。统计分析证实两者呈显著正相关（ｒ＾２＝０．８０６６）。这一结果表明,ＵＶ－Ｂ对绿豆下胚轴生长的抑制作用与不胚轴细胞伸长受到抑制相关。     

Ca2+ Activated Protein Kinases in Hypocotyl of Soybean (Glycine max L.)

The soluble protein extract of soybean hypocotyl was autophosphorylated, the labeling products were analyzed by SDS-PAGE. A 18 kD protein band was intensely labeled when a relatively high concentration of calcium was present, meanwhile a weakly labeled 67 kD protein band was also observed. When the reaction time was prolonged to 15 or 30 min, the labeling intensity of them was weakened gradually and the labeled bands disappeared eventual ly from the autoradiograph. If the calcium chelater EGTA was added into the reaction sys tem, only 67 kD was phosphorylated with high intensity. When non-labeled ATP was added during the reaction process, 32p in the labeled proteins could be substituted gradually by Pi. This indicated that the reaction system was in a dynamic equilibrium of phosphorylation-de- phosphorylation. There were also data inferred that it was a calcium dependent process. Histon H1 could speed up the phosphorylation, suggesting that it was a suitable substrate for protein kinases in the extract. Findings support that 18 kD and 67 kD protein may be Ca2+ sensitive protein kinases that can be autophosphorylated. Their different responses to Ca2+ may make the calcium signal transduction controllable.     

PEG法介导转化诸葛菜下胚轴原生质体获得转基因植株

采用诸葛菜无菌苗的下胚轴组织为材料,分离原生质体,在原生质体培养基中作液体浅层暗培养,植板率为５％,植株再生频率为１００％。作者进而开展了遗传转化研究。为研究ＰＥＧ介导转化诸葛菜原生质体的影响因素,通过瞬间表达,实验了ＰＥＧ法转化子叶原生质体的过程,在此基础上将分离纯化后的原生质体与带ＨＰＴ基因的质粒ＤＮＡ（ｐＢＩ２２２）混合,ＨＰＴ基因作选择标记,ＰＥＧ介导转化;重新收集转化后的原生质体,以５×１０４／ｍｌ的密度在原生质体培养基中作浅层培养;培养１０—１５天后用２５ｍｇ／Ｌ的潮霉素（ｈｙｇｒｏｍｙｃｉｎ）进行筛选,一月后出现少量细胞团,转入含潮霉素５０ｍｇ／Ｌ的扩增培养基扩增愈伤组织,进而转入含５０—１００ｍｇ／Ｌ潮霉素的分化培养基诱导分化成苗,分化率为１００％,转入生根培养基中生根成完整植株。抗性植株再生率为４×１０（－５）。在获得再生转基因植株后,以再生植株叶片为材料,进行Ｓｏｕｔｈｅｒｎｂｌｏｔ分子杂交,证实外源基因已稳定整合到植物基因组中并表达,再生转基因植株频率为１０（－５）。国内外首次转化诸葛菜属植物原生质体获得成功。     

Culture of Cotyledon and Hypocotyl Protoplasts from True Potato Seedlings in Solanum tuberosum L.

Culture of protoplast using cotyledon and hypocotyl as the donor tissue from true potato seedlings (TPSs) of 3 breeding lines (DTO-33, ND 860-2 and BN 9815-3) of Solanum tuberosum L. was studied. The cotyledons and hypocotyls of TPSs just extended were excised and digested in an enzyme solution containing 1 % cellulase and 0. 5 % macerozyme for 17—20 h after vacuum infiltration of the tissue in the solution. The protoplasts were cultured in an improved liquid medium and transferred onto solid media for callus culture and shoot regeneration. Some factors affecting the efficiency of cotyledon and hypocotyl protoplast culture were studied. The results showed that using the cotyledons and hypocotyls as donor tissues for protoplast isolation and culture in potato, the division frequency of protoplast derived cells was significantly higher than that using the leaves and shoot-tips of the test-tube plantlets: the yield and quality of the protoplast from TPSs cultured under continuous high light intensity (3000 Ix) were much higher than the TPSs cultured under low light intensity (1000 Ix), and no intact protoplast was ever obtained from the TPSs cultured in continuous dark condition. Vacuum infiltration of the cotyledon and hypocotyl segments in enzyme solution before digestion increased protoplast yield. The yield of protoplasts from hypocotyl tissue was significantly higher than from the cotyledon, but there was no significant difference in quality between the protoplast derived from the two tissues. The significance, advantages and shortcomings of using the cotyledons and hypocotyls as the donor tissues for isolation and culture of potato protoplasts are dicussed.     

Cell Elongation and Microtubule Behavior in the Arabidopsis Hypocotyl: Responses to Ethylene and Auxin

During elongation of the Arabidopsis hypocotyl, each cell reacts to light and hormones in a time- and position-dependent manner. Growth in darkness results in the maximal length a wild-type cell can reach. Elongation starts at the base and proceeds in the acropetal direction. Cells in the upper half of the hypocotyl can become the longest of the whole organ. Light strongly inhibits cell elongation all along the hypocotyl, but proportionally more in the upper half. The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) is known to stimulate hypocotyl elongation in the light. Here we show that this stimulation only occurs in cells of the apical half of the hypocotyl. Moreover, ACC application can partially overcome light inhibition, whereas indole-3-acetic acid (IAA) cannot. On low-nutrient medium (LNM) in the light, elongation is severely reduced as compared to growth on rich medium, and both ACC and IAA can stimulate elongation to the levels reached on a nutrient-rich medium. Furthermore, microtubule orientation was studied in vivo. During elongation in darkness, transverse and longitudinal patterns are clearly related with rates of elongation. In other conditions, except for the association of longitudinally orientated microtubules with growth arrest, microtubule orientation is merely an indicator of developmental age, not of elongation activity. A hypothesis on the relation between microtubules and elongation rate is discussed.     

木犀属植物叶柄的比较解剖学研究

对木犀属(Osmanthus)26种植物叶柄的解剖结构进行了研究.结果表明,木犀属植物叶柄的解剖特征存在比较丰富的变异,叶柄横切面形状有3种类型(U型、V型、Y型),周缘波状、浅波状或近平滑;表皮毛有或无;维管束一般为1大2小,维管束轮廓在种问变异丰富,维管束类型有周韧、近周韧、外韧3种;小叶月桂、牛矢果、厚边木犀、美洲木犀叶柄中央具髓腔,部分种叶柄有硬化细胞或石细胞存在.木犀属植物叶柄的解剖结构特征比较稳定,可作为该属的分种特征.     

黄瓜和绿豆下胚轴不定根发生的研究

在MS基本培养基上,黄瓜和绿豆幼苗的下胚轴切段培养4d时即可见不定根发生。下胚轴不同部位切段的发根能力不同。下胚轴切段反插时比正插时发根快1-2d,发根率也高于正插的;0.01-0.05mg/L的NAA还诱导下胚轴切段在形态学上端发根。TIBA对正插或反插的下胚轴切段的不定根发生都有抑制作用。结果提示,生长素极性运输活性对不定根形成起着重要作用。     

Anatomical Studies of Chunia Wood

Chunia is a monotype of Hamamelidaceae in China. The wood structure of this genus possesses some primitive properties, such as the inclining end-wall of vessel elements, the scalariform perforation plates, the absence of spiral thickening in the wall, the heterogenous rays, crystal inclusion in Cell, and scanty parenchymatous cells in the axial system. On account of its intimate relation to the genus Mytilaria, therefore, both may be represented as primitive genera in this family.     

Anatomical Studies on Secondary Phloem of Pinus bungeana

This paper deals with structures of the secondary phloem of Pinus bungeana Zucc. The sieve cells lived for only one growing season. Most of them formed in spring and summer and then died in the end of winter. However, some of them formed in autumn and died eventually in the end of next spring. Two types of albuminous cells: type A and type B were seen in radial plates and rays, which possessed the following common characteristics, there were unilateral sieve area connections between these and the sieve cells. These cells had larger nuclei, denser cytoplasm with abundant mitochondria and rich RNA-protein. Their death closely followed that of the sieve cells. Type A albuminous cells differed from type B in that the former collapsed before the contents of sieve cells accompanied with it dissppeared. But, type B did not collapse until complete disappearance of the contents of sieve cells. The cytological characteristics of albuminous cells, the relationship between radial plates and rays, and possible physiological significance are also disscussed.     

Anatomical Studies on Secondary Phloem of Euonymus bungeanus

The anatomical structures, especially the type, distribution and arrangement of the constituent elements in the secondary phloem of Euonymus bungeanus Maxim. have been studied. The results showed that the secondary phloem was thicker, consisted of sieve-tube elements, companion ceils ,phloem parenchyma cells ,secretory ceils and rays. Sieve-tube elements, phloem parenchyma cells and secretory cells were alternately arranged in tangential bands, forming a conspicuous zone-like constitution. There was no obvious boundary between the functional phloem and the non-functional phloem. Sieve-tube elements were long, slender cells with very oblique end walls and compound sieve plates. Sieve areas on lateral wall were highly differentiated. Companion cells were triangular in transection and slender in radial section. Mostly,two or three companion cells stayed along with one sieve-tube element. In the functional phloem, phloem parenchyma cells were also slender, containing a few starch grains;but in the nonfunctional phloem they enlarged and contained abundant starch grains. Secretory cells were longer than sieve-tube elements, consisting of rubber-like material. Rays were uniseriate. Finally, the authors also discussed the phylogenetic position of E. bungeanus, which may provide some references for further study of the classification of different genera of Celastraceae.     

Comparative Anatomical Studies on Root Structure of Ranunculaceae

This paper deals with comparative studies of the root structure in 65 species of 36 genera of Ranunculaceae. Five types of the root structure were recognized in these species. A. The roots, in which the primary xylem was surrounded by the tracheary elements of the secondary xylem and the ray was absent, were always diarchy, as seen in Coptis. B. The rays were narrow and the tracheary elements of the secondary xylem were semicircle in shape, and the roots were diarchy, as seen in Leptopyrum. C. The rays and tracheary elements of the secondary xylem were sector in shape, and the roots were di-, tri-, and tetrarchy, as seen in Cimicifuga, etc. D. There was a few secondary xylem in the roots. D1. Primary structure was diarchy, in Kingdonia. D2. The roots were di-, tri-, tetra- and pentarchy, in Ranunculus etc. E. The secondary structure was absent. El. The roots were diarchy, in Asteropyrum. E2. They were di-, tri-, tetra- and pentarch, as seen in Caltha. According to comparative anatomical studies on the characteristics of the vessel elements and other parts of plant (carpel, petiole and vena- tion), the roots which were always diarcby whether in older or young, and whether the tra- .cheary elements of the secondary xylem well orless developed, could be considered as the most primitive type, for example: type A (Coptis) and type El (Asteropyrum). It would be con- cluded that the evolution of the root structure from primitive to specialized type was in the order from type A→B→C→D2→E2 and E1→D1 in Ranunculaceae.     

紫萍营养繁殖过程的解剖观察

以采自海南陵水的紫萍(Spirodela polyrhiza DW2501-4)为材料,观察紫萍的营养繁殖过程。紫萍DW2501-4培养在0.5倍Hoagland′s液体培养基中,先不断长出新的叶状体,随着营养物质的减少,长出休眠体进入休眠状态。休眠体经过4℃处理7 d后,可在含1%蔗糖的Hoagland′s固体培养基中重新萌发。为了进一步观察叶状体、类休眠体和休眠体的组织结构差异,以及休眠体萌发过程中组织结构的变化,制作了石蜡切片。观察结果显示:紫萍叶状体有数条叶脉,细胞中含少量的淀粉粒,表皮层以下有分层的气室,通常分上下两层,上层气室比下层气室小。类休眠体也有数条叶脉和少量气室,细胞中有较多淀粉粒。休眠体的细胞差异不明显,几乎没有气室,细胞内有大量的淀粉粒,部分细胞含有单宁;随着休眠体萌发,细胞中淀粉粒不断变小,同时分生组织分化出根和新的叶状体。