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1.
Dinesh Chandra Sharma Mohd Sajid Khan M Salman Khan Rashmi Srivastava Ashwini Kumar Srivastava Ritu Shukla 《Bioinformation》2014,10(5):316-319
The occurrence of a large number of fossil woods having resemblance in anatomical features with the modern palm genus, Phoenix
L in Deccan Intertrappean fossil flora of Maastrichtian-Danian age (i. e. Late Cretaceous and Earliest Tertiary (65-67 my)) indicates
the most primitive record of date palm. Present discovery of biocompounds from fossil wood of Phoenix collected from Deccan
Intertrappean having affinity with the biocompounds known from modern plant further exemplify the earliest documentation of
Phoenix in Indian peninsula. 相似文献
2.
Premise of research
A large number of fossil coryphoid palm wood and fruits have been reported from the Deccan Intertrappean beds of India. We document the oldest well-preserved and very rare costapalmate palm leaves and inflorescence like structures from the same horizon.Methodology
A number of specimens were collected from Maastrichtian–Danian sediments of the Deccan Intertrappean beds, Ghughua, near Umaria, Dindori District, Madhya Pradesh, India. The specimens are compared with modern and fossil taxa of the family Arecaceae.Pivotal results
Sabalites dindoriensis sp. nov. is described based on fossil leaf specimens including basal to apical parts. These are the oldest coryphoid fossil palm leaves from India as well as, at the time of deposition, from the Gondwana- derived continents.Conclusions
The fossil record of coryphoid palm leaves presented here and reported from the Eurasian localities suggests that this is the oldest record of coryphoid palm leaves from India and also from the Gondwana- derived continents suggesting that the coryphoid palms were well established and wide spread on both northern and southern hemispheres by the Maastrichtian–Danian. The coryphoid palms probably dispersed into India from Europe via Africa during the latest Cretaceous long before the Indian Plate collided with the Eurasian Plate. 相似文献3.
A new species of Enigmocarpon, E. sahnii is described in this paper. It is an eight-locular petrified dicotyledonous, loculicidal capsule from the Mohgaonkalan (Danian, uppermost Cretaceous) beds of the Deccan Intertrappean Series of India. The fruit is small, globular, with six to eight seeds horizontally packed back to back in alternating rows in each locule and showing stalked glandular outgrowths on the septae and the inner wall of the fruit. The placenta, raphe and the fruit wall are spongy. 相似文献
4.
互花米草(Spartina alterniflora)的入侵给海岸带盐沼生态系统的结构和功能带来了显著影响。互花米草盐沼中的硫含量高于附近的土著芦苇(Phragmites australis)盐沼。为探讨硫元素对互花米草和芦苇竞争过程的可能影响及其作用机制, 以50 mmol·L-1的Na2SO4和Na2S对互花米草和芦苇进行处理, 分析处理前后5天内两种植物光合气体交换和叶绿素荧光指标变化的差异, 实验另设等Na+浓度的NaCl处理作为比较。研究发现: Na2S对互花米草和芦苇光合作用影响的差异最大, NaCl次之, Na2SO4最小。Na2S处理后, 互花米草净光合速率(Pn)出现显著上升, 芦苇Pn值大幅度下降。互花米草的光饱和点(Isat)上升而芦苇的Isat值无变化。表明Na2S处理对互花米草的光合能力有促进作用, 但对芦苇的光合能力有抑制作用。NaCl处理后互花米草Pn值也出现小幅上升, 而芦苇Pn值略有下降。Na2SO4处理对互花米草和芦苇的Pn值均无显著影响。除Na2SO4处理的互花米草外, 不同盐处理后的互花米草和芦苇非光化学淬灭(NPQ)均出现上升趋势。研究结果表明互花米草对环境硫胁迫的适应能力显著高于芦苇, 暗示盐沼高硫环境尤其是硫化物有助于互花米草相对于芦苇的竞争, 也很可能是其形成单一植被的重要原因之一。 相似文献
5.
John W. Hall 《American journal of botany》1961,48(8):731-737
Hall , John W. (U. Minnesota, Minneapolis.) Anachoropteris involuta and its attachment to a Tubicaulis type of stem from the Pennsylvanian of Iowa. Amer. Jour. Bot. 48(8): 731–737. Illus. 1961.—Petioles referable to Anachoropteris involuta are described, attached to a stem which most nearly corresponds to a member of the genus Tubicaulis. These petioles are attached in a 2/5 phyllotaxy. At their points of departure petiole traces are massive and C-shaped but become involute in regions away from their attachment. Adventitious roots were borne on the stem in partial whorls. It is suggested that Anachoropteris petioles were extremely long and that they bore adventitious stems at intervals. These, in turn, bore adventitious roots, perhaps to serve for uptake of minerals or support in regions removed from the true stem. Such a “petiole unit” may also have functioned as a vegetative propagule. This would account for the apparent rarity of true stems and the abundance of petioles in coal balls. 相似文献
6.
A new genus and species of Cretaceous Cyatheacean tree fern, Heilongjiangcaulis keshanensis gen. et sp. nov., is erected for several permineralized stems collected at the Keshan County in Songliao Basin, Heilongjiang Province, Northeast China. The new taxon is characterized by a dictyostelic, erect stem with dense multicellular scales and surrounded by persistent petiole bases and adventitious roots. The stem contains a central pith lacking medullary bundles, which is surrounded by a dictyostele, and the cortex externally. Each meristele of the dictyostelic ring is enclosed by a sclerenchyma sheath. The pith and cortex are parenchymatous. The proximal petiole bases present a frond trace composed of numerous meristeles, arranged in 1 abaxial and 2 adaxial arcs, with internally projecting bundles on the upper and lateral sides. The feature combination of the new genus is nearly identical to the anatomical structures of modern scaly genera of the Cyatheaceae apart from the absence of medullary bundles. It is interpreted as a primitive representative of early Cyatheaceae, that closely resembles the modern scaly genera, which suggests that in the Cretaceous, the tree ferns in this family were already in possession of most of the anatomical characteristics observed in extant taxa. The fossil records of the stems, petioles, and spores indicate that during the Jurassic and Cretaceous, the Northeastern region of Asia may have been one of the distribution centers of early Cyatheaceae. 相似文献
7.
The families Achariaceae and Salicaceae (Malpighiales) are characterized by wood anatomical ranges that partly overlap. Formerly these families were treated together in the polyphyletic Flacourtiaceae and a much more narrowly circumscribed Salicaceae. Here we attribute two recently collected fossil woods from the Deccan Intertrappean Beds to the clade that contain these two families, i.e., the Parietal Clade of the Malpighiales. The new genus Elioxylon shares features with several extant genera of Achariaceae and Salicaceae, but does not completely match with any of them. A new record of Hydnocarpoxylon indicum Bande & Khatri is a good match for extant Hydnocarpus Gaertn. (Achariaceae). Elioxylon and Hydnocarpoxylon share an absence of parenchyma, the presence of septate fibres and 1–3 seriate heterocellular rays with long uniseriate margins consistent with Achariaceae and Salicaceae. Elioxylon has mixed simple and scalariform perforations, whereas Hydnocarpxylon has exclusively scalariform perforations. Other Deccan fossils formerly attributed to “Flacourtiaceae” in the literature are critically discussed and mostly excluded from Achariaceae and Salicaceae. Elioxylon and Hydnocarpoxylon from the Maastrichtian ‐ Danian of India are the oldest fossil records of the Parietal Clade of the Malpighiales. With their occurrence on the Indian plate during its northward journey from Gondwana to Laurasia, these fossils provide further support for an ‘out‐of‐India’ hypothesis for Achariaceae and/or Salicaceae. “Baileyan trends” in vessel perforation plate and vessel grouping evolution are apparent in the phylogeny of the Parietal Clade. 相似文献
8.
Howard J. Falcon-Lang 《Palaeontology》2004,47(2):349-366
A new genus of ginkgoalean woody branch, Pecínovicladus kvaceki gen. et sp. nov., is described from the Upper Cretaceous (mid to late Cenomanian) Peruc-Korycany Formation at Pecínov Quarry, near Prague, Czech Republic. Eighteen branch specimens, anatomically preserved as charcoal, the product of wildfire, occur as allochthonous assemblages in intertidal facies and as parauthochthonous assemblages in supratidal salt marsh facies. Primary branches range from 7–13 mm in diameter, and are composed of a central, parenchymatous pith, a medial pycnoxylic xylem layer, and an outer periderm layer. Closely spaced, helically arranged leaf bases and rare secondary branch scars characterize the exterior. The branches are confidently referred to the Ginkgoales on the basis of a variety of diagnostic xylem features, most notably the presence of inflated axial parenchyma containing moulds of crystals, and by the precise anatomical correspondence of the leaf bases to those of detached, but facies-associated Nehvizdya obtusa leaves of known ginkgoalean affinity. The newly described ginkgoalean, together with cheirolepidiaceous conifers, formed fire-prone vegetation in halophytic salt marsh environments under a seasonal, subtropical climate. 相似文献
9.
Non-marine diatoms occur in the Deccan Intertrappean beds (Upper Cretaceous) of Mohgaon-Kalan, Chhindwara District, Madhya Pradesh and Pisdura, Lameta Formation (Upper Cretaceous), Maharashtra, India. This represents the oldest record of non-marine diatoms yet reported and the oldest from the Indian subcontinent. The diatoms were recovered from thin sections of chert and dinosaur coprolites by random fracturing. Solitary forms are the most common but colonial filaments up to five cells were also observed. Based on the morphological characters, the diatoms are identified as Aulacoseira Thwaites. The Lower Cretaceous marine diatom genus Archepyrgus Gersonde and Harwood also resembles Aulacoseira in general morphological characters and it seems that Aulacoseira evolved from Archepyrgus and migrated to the non-marine realm. 相似文献
10.
Pearson GA 《Plant physiology》1967,42(9):1171-1175
At the end of a 4 hour absorption period approximately 95% of the sodium absorbed by bean plants was retained in the secondary roots. The sodium translocated to the shoot was retained in the stem.
2,4-Dinitrophenol decreased the amount retained in the secondary roots of bean plants and increased the amount translocated to the shoot. The stem retained most of the translocated sodium.
Bean plants without roots absorbed considerably more sodium than plants with roots and translocated a greater proportion of the sodium to the petioles and blades. 2,4-Dinitrophenol reduced the amount of sodium in the stem and petioles and increased the amount in the blades.
2,4-Dinitrophenol reduced the amount of sodium retained by the secondary roots of cotton plants but did not appreciably affect the amounts translocated to the shoot.
相似文献11.
A new species of the Osmundaceae, Plenasium xiei sp. nov., is herein described from the Cretaceous of Northeast China. The specimens examined here represent the earliest unequivocal record of the extant genus Plenasium in Eurasia based on fossil rhizomes. The rhizome consists of a central stem with a mantle of petiole bases and adventitious roots. The stem contains an ectophloic‐dictyoxylic siphonostele and a two‐layered cortex. The C‐shaped leaf trace bears two protoxylem bundles at the point of separation from the stele. The pith is heterogeneous. The parenchymatous inner cortex is thinner than the sclerenchymatous outer cortex. Lobed sclerenchyma bands occur at the adaxial sides of the stem xylem strands, in the concavity of the leaf trace, and along the adaxial side of the vascular bundles of the petiole base. In distal petiole portions, the sclerenchyma band splits into several groups in the transverse view. Sclerenchyma rings are heterogeneous with an abaxial sclerenchymatous arc of thick‐walled fibers. Numerous sclerenchyma strands of thick‐walled fibers appear in the petiolar inner cortex and the stipular wing. These fossils provide unambiguous evidence for the existence of subgenus Plenasium of modern Plenasium by at least the Late Cretaceous, demonstrating the longevity of this extant subgenus. Altogether the leaf and rhizome fossil records of Plenasium indicate that this genus was widely distributed across North America and Eurasia from the Early Cretaceous to the Early Cenozoic, followed by a range restriction to Eurasia in the Late Cenozoic. Extant Plenasium species are only known from East and Southeast Asia. 相似文献
12.
本研究选择闽江河口鳝鱼滩芦苇和短叶茳芏空间扩展前的芦苇湿地、短叶茳芏湿地,以及二者空间扩展形成的交错带湿地为对象,探讨了两种植物空间扩展过程中植物-土壤系统的全磷(TP)赋存特征及其主要影响因素。结果表明: 在空间扩展影响下,湿地植物和土壤的TP含量均发生了明显变化。其中,交错带湿地土壤的TP含量比芦苇湿地和短叶茳芏湿地土壤分别增加了20.0%和7.1%。这与芦苇和短叶茳芏空间扩展过程中土壤的颗粒组成以及植物的生物量、根冠比变化有关。除叶外,交错带芦苇不同器官的TP含量整体均低于短叶茳芏的相应器官。这与二者在交错带生境中对P养分吸收利用与转运方式的差异有关。另外,空间扩展导致的竞争作用使二者的P分配比也发生较大变化,与纯群落相比,交错带芦苇提高了根、叶的P分配比,而交错带短叶茳芏提高了根的P分配比。芦苇和短叶茳芏为了应对空间扩展过程中的竞争可能采取了不同的P养分利用策略,前者通过加强根部P养分吸收和提高叶片光合作用的方式来占据竞争优势,而后者通过提高根系生物量以增强对P养分吸收利用的方式来抗衡来自芦苇的竞争。 相似文献
13.
博落回(Macleaya cordata)是罂粟科含有异喹啉生物碱的主要药用植物, 其生物碱提取物具有多种药理活性。目前对博落回的研究主要集中在生物碱的成分、活性和药理等方面, 对与其合成、运输、储藏密切相关的发育解剖结构及生物碱组织化学定位研究还未见报道。该文报道了温室中生长的博落回植株形态特征, 并结合徒手切片和改良碘化铋钾沉淀的方法对主要器官(根、茎、叶)的发育结构和生物碱组织化学染色进行了初步分析。结果表明, 博落回发育基本遵循一般双子叶植物的规律。根中生物碱出现在中柱鞘外的薄壁细胞和导管周围。茎和叶柄中的生物碱主要出现在维管束周围, 偶尔也出现在茎的髓细胞中。总体上, 茎中的生物碱积累量少于根。 相似文献
14.
Zhong-Jian Liu 《Historical Biology》2017,29(4):431-441
Despite increasing claims of pre-Cretaceous angiosperms, whether there really are angiosperms in the Jurassic is apparently still an open question for many people before further evidence is available. This question can only be answered by studying more Jurassic plant fossils. Here we report a fossil angiosperm, Yuhania daohugouensis gen. et sp. nov, from the Middle Jurassic of Inner Mongolia, China. The plant includes connected stem, leaves, flowers, aggregate fruits, fruitlets, and seeds within fruitlets. The leaves are helically arranged along the curving stem, linear in shape, with 5–6 parallel veins. The aggregate fruit is pedicellate, composed of over 20 carpels/fruitlets helically arranged. Each fruitlet encloses a seed. The reproductive organs in various stages are found in the same plant, allowing us to understand the development of Yuhania. The occurrence of Yuhania in the Middle Jurassic re-confirms the Jurassic history for angiosperms that has been suggested by other independent research and adds to the on-going study on the early evolution of angiosperms. 相似文献
15.
Gibberellin Effect on Tryptophan Metabolism, Auxin Destruction, and Abscission in Coleus 总被引:1,自引:0,他引:1
Application of gibberellic acid (GA) to the apical region of the stem enhances 14CO2 release from tryptophan-l-14C in cell free preparations of the apical region. Although GA when applied to the apical region markedly accelerates abscission rates of debladed petioles at the 4th node, the enhancement effect on tryptophan metabolism appears to be restricted to the apical bud region. The increased levels of diffusible auxin in Coleus stems, observed earlier by Muir and Valdovinos (1965), appear to be due to the GA effect on auxin precursor conversion rather than to an altered rate of auxin destruction. GA pre-treatment does not significantly alter destruction rates of auxin in the stem tissue. This is demonstrated by the release of 14CO2 from IAA-1-14C by sections of internode tissue. While a multiple deblading pattern retards abscission of debladed petioles considerably, application of GA to debladed petioles at the basal region of the stem restores the normal rates of abscission at debladed distal nodes. No significant change in the abscission rates at treated nodes is observed. The GA effect on abscission at distal nodes is attributed to the effect of the growth substance on auxin precursor conversion in the apical region. In these experiments, as in the case of plants treated in the apical region with GA, auxin destruction rates in the stem are not altered significantly. 相似文献
16.
S. D. CHITALEY F.L.S. S. A. PARADKAR 《Botanical journal of the Linnean Society. Linnean Society of London》1972,65(1):109-117
A detailed investigation of Rodeites Sahni from nearly 100 specimens collected from the Deccan Intertrappean beds of India has brought to light some new important facts: (1) The sporocarp wall is thicker and the spores within it are larger than hitherto described. (2) The mode of sorus attachment, observed for the first time, is similar to that of Marsilea rather than Regnellidium. (3) The presence of a distinct cellular gametophyte inside some megaspores is an entirely new finding for the family Marsileaceae. The presence of a male prothallus inside smaller microspores is also newly observed. (4) The occurrence of sporocarps in groups and their attachment are unique. (5) The prismatic layer is distinct in the sporocarp wall of Rodeites The above observations help in reconsidering the position of Rodeites in the Marsileaceae. 相似文献
17.
The effect of water level management on the soils and vegetation of two coastal Louisiana marshes 总被引:4,自引:1,他引:4
Wetland degradation and loss is the result of a combination of natural causes and anthropogenic activities and is a serious problem in coastal Louisiana, where approximately 80% of the total US coastal wetland loss since the 1930's has occurred. One method currently used to address this wetland loss problem is structural marsh management, which is the use of levees and water control structures to control hydroperiod. The effects of structural marsh management on two managed marshes in Southern Louisiana (Unit 4 of the Rockefeller Wildlife Refuge and the Fina LaTerre Mitigation Bank) were evaluated by comparing the soils and the dominant emergent marsh vegetation (Spartina patens) of the two managed marshes with those of two nearby unmanaged marshes. Soil redox potential, water depth, interstitial water sulfide concentration, salinity, NH4-N and elemental concentrations of Na, K, Ca, Mg, P, Fe and Zn were measured four times during 1989 which was a drawdown year. Net and total CO2 exchange rate, primary productivity, leaf area, stem density, and live, dead and total aboveground biomass were also measured. The managed marsh at Rockefeller had lower water levels, significantly less reduced surface and 15 cm deep soils and significantly lower interstitial sulfide concentrations and salinity levels. Na, K, Mg and Ca concentrations reflected the same pattern as salinity. Live aboveground biomass, primary productivity and leaf area were 3–4 times greater in the managed marsh. This indicates that marsh management improved soil conditions and provided an environment favorable to more vigorous plant growth. The management scheme at Fina LaTerre was also successful at maintaining lower water levels than in the adjacent unmanaged area. However, surface soils were more reduced and interstitial salinity higher, on average, in the managed marsh indicating generally poorer water circulation. Primary productivity was 50% less and stem density, leaf area, net CO2 and total CO2 exchange rates were significantly lower in the managed marsh, compared to the nearby reference marsh. Conditions in the managed marsh indicate that the management scheme was not successful at improving soil conditions when compared to those in the adjacent unmanaged marsh. This study indicates that structural marsh management is not the universal answer to problems faced by Louisiana's coastal wetlands, but may be of value in specific situations. 相似文献
18.
We report exceptionally well-preserved plant remains ascribed to the extinct conifer Glenrosa J. Watson et H.L. Fisher emend. V. Srinivasan inside silica-rich nodules from the Cenomanian of the Font-de-Benon quarry, Charente-Maritime, western France. Remains are preserved in three dimensions and mainly consist of fragmented leafy axes. Pollen cones of this conifer are for the first time reported and in some cases remain connected to leafy stems. Histology of Glenrosa has not previously been observed; here, most of internal tissues and cells are well-preserved and allow us to describe a new species, Glenrosa carentonensis sp. nov., using propagation phase-contrast X-ray synchrotron microtomography, a non-destructive technique. Leafy axes consist of characteristic helically arranged leaves bearing stomatal crypts. Glenrosa carentonensis sp. nov. differs from the other described species in developing a phyllotaxy 8/21, claw-shaped leaves, a thicker cuticle, a higher number of papillae and stomata per crypt. Pollen cones consist of peltate, helically arranged microsporophylls, each of them bearing 6–7 pollen sacs. The new high resolution tomographic approach tested here allows virtual palaeohistology on plants included inside a dense rock to be made. Most tissues of Glenrosa carentonensis sp. nov. are described. Lithological and palaeontological data combined with xerophytic features of Glenrosa carentonensis sp. nov. suggest that this conifer has been adapted to survive in harsh and instable environments such as coastal area exposed to hot, dry conditions. 相似文献
19.
从福建多地采集了55份感染叶斑病的枫香植物病样,包含叶片、叶柄、枝条和树皮。通过分离纯化得到了12个类拟盘多毛孢属真菌菌株,综合形态特征以及3个基因(ITS、β-tubulin和tef1)的分子系统发育分析结果,分别鉴定为Neopestalotiopsis cocoes、N. chrysea、Pestalotiopsis neglecta和P. neolitseae,均为枫香上首次报道,其中N. cocoes在国内首次被发现。通过柯赫氏法则验证,发现N. cocoes能够侵染叶片、叶柄和枝条,N. chrysea能侵染叶片和枝条,P. neglecta能侵染叶柄和枝条,而P. neolitseae不能侵染枫香植物组织。 相似文献
20.
Tetsuo Katsumoto Tomonori Naguro Yun-Li Yan Akihiro Iino Kazukiyo Onodera 《Biology of the cell / under the auspices of the European Cell Biology Organization》1993,77(3):247-253
Summary— The spatial distribution of the microtubules (MT) in the rat 3Y1 cells in mitosis was investigated by immunoelectron microscopy and computer-graphic reconstruction of serial thin sections. In anaphase the interzone-MT increased in number gradually with advancing phase, while the kinetochore-MT in half-spindles decreased. The interzone-MT overlapped with each other at the equatorial region of the cell, and they formed a specific structure called the ‘stem bodies’. The ends of the interzone-MT opposite to the stem bodies often attached to chromosomes but not to the poles. The stem bodies were not labeled with immunogold particles of anti-α tubulin. Some of the stem bodies or MT which originate from stem bodies were found just beneath the plasma membrane in the equatorial region where abundant actin filaments appear showing the formation of the contractile ring and subsequently the cleavage furrow begins. On the basis of these observations it is assumed that the interzone-MT is involved both in the separation of chromosomes in anaphase and in the formation of the cleavage furrow in telophase. 相似文献