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David L. Hawksworth 《Plant Systematics and Evolution》1985,149(3-4):303-307
The nomenclatural history of the generic nameParmeliopsis is reviewed. Its correct citation is found to beParmeliopsis (Nyl. exStizenb.)Nyl., dating from 1866, not 1869 as commonly cited, withP. placorodia (Ach.)Nyl. as holotype species. There is consequently no nomenclatural problem to the adoption ofForaminella
Fricke Meyer, typified byF. ambigua (Wulfen)Fricke Meyer for theParmeliopsis species with falcate conidia. A synopsis of the nomenclature of the North American and European species of both these genera is included. 相似文献
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Gerhard Pils 《Plant Systematics and Evolution》1980,136(1-2):73-124
The biosystematics of theFestuca violacea group (F. rubra subsp.violacea sensuHackel) in the Eastern Alps is studied.F. picturata
Pils (=F. picta
Kit. exSchultes nonJ. F. Gmelin) is confirmed as diploid, whereas the chromosome numbers forF. nitida (diploid),F. puccinellii (hexaploid), andF. norica (diploid, tetraploid and hexaploid) are reported for the first time. Details of morphology, leaf anatomy, and epidermal structures now allow a better separation of these species; new maps illustrate their distribution. Karyological, chorological, morphological, and anatomical data form the basis for a discussion of the phylogeny of theF. violacea group and its position withinF. rubra s. latiss. 相似文献
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In this study, the antiulcerogenic effect of a water extract obtained from the lichen species Usnea longissima was investigated using indomethacin-induced ulcer models in rats. Experimental groups consisted of six rats. Antiulcerogenic activities of 50, 100 and 200mg/kg body wt. doses of the water extract were determined by comparing the negative (treated only with indomethacin) and positive (ranitidine) control groups. Although all doses of the water extract of U. longissima showed significant antiulcerogenic activity as compared to negative control groups, the highest activity was observed with 100 mg/kg body wt. doses (79.8%). The water extract of U. longissima showed moderate antioxidant activity when compared with trolox and ascorbic acids used as positive antioxidants. In addition, the activities of antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST)] were determined in the stomach tissues of rats and compared with those of the negative and positive control groups to expose the effects of antioxidant enzymes on antiulcerogenic activity. SOD and GST enzymes activities in indomethacin-administrated tissues were reduced significantly by indomethacin in comparison to control groups. These enzymes were activated, however, by the water extracts of U. longissima. In contrast to SOD and GST activities, CAT activity was increased by indomethacin and reduced by all doses of U. longissima and ranitidine. The present results indicate that the water extract of U. longissima has a protective effect in indomethacin-induced ulcers, which can be attributed to its antioxidant potential. 相似文献
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Wilfried Morawetz 《Plant Systematics and Evolution》1981,139(1-2):57-76
Detailed analyses of karyology and leaf morphology do not support relationships betweenFlacourtiaceae andTiliaceae. In spite of different chromosome numbers,Prockia (2n = 18),Flacourtia (2n = 22) andRawsonia (2n = 22) are very similar in karyomorphology, indicating a certain karyological uniformity withinFlacourtiaceae. Lacistema (2n = ca. 62) appears more isolated. On the other hand, theTiliaceae Grewia (2n = 18) andLuhea (2n = 36) have much in common and differ remarkably from the Flacourtiaceous genera. The salicoid leaf-teeth ofProckia are also found inIdesia, but never inTiliaceae. Epidermis ultrastructure reveals certain relationships betweenProckia andFlacourtia in contrast to the strongly differingGrewia. Idesia has a rare und unique epidermis sculpture. — Basic chromosome numbers and chromosomal evolution within theFlacourtiaceae are discussed. 相似文献
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Lothar Geitler 《Plant Systematics and Evolution》1977,127(1):39-43
After allogamous pairingEunotia tenella produces in each partner cell one gamete containing the two chromatophores of the mother cell and one abortive protoplast without chromatophores. This distribution results from a differential cytokinesis which exhibits the same constant orientation in regard to the epi- resp. hypotheka as in other species ofEunotia. Moreover inEu. tenella andEu. spec. the significant right hand—left hand dissymmetry during the growth of the daughter chromatophores in vegetative cytokinesis is the same as in other species. Both phenomena are significant for the genus and unique. In connection with the diminution of cell size in vegetative divisions the bending of the valvae increases to a certain degree.
Zur Morphologie und Entwicklungsgeschichte vonEunotia-Arten (Bacillariophyceae)相似文献
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Zoospore ultrastructure (incl. flagellar apparatus) has been investigated in three species ofTrebouxia (T. glomerata, T. erici, T. pyriformis) and one species ofPseudotrebouxia (P. impressa) using an absolute configuration analysis. Zoospores in all taxa studied are nearly identical in ultrastructure and exhibit a very distinctive disposition of cell organelles: cells are naked, biflagellate and considerably flattened along the plane of flagellar beat, the single contractile vacuole is located anteriorly in the ventral region of the cell, the nucleus is anteriorly to centrally located in the dorsal region of the cell. A single dictyosome is located close to the anterior, ventral edge of the nucleus. The chloroplast occupies a posterior position in the cell and usually has an anterior profile in the left region of the cell. There are two branched mitochondria per cell or a single mitochondrial reticulum with profiles anterior to the nucleus (in the dorsal region of the cell), and posterior to the nucleus. In zoospores ofTrebouxia spp. the posterior mitochondrial profile is associated with a microbody, inP. impressa zoospores the anterior mitochondrial profiles are associated with a microbody. The zoospores contain a distinctive system of three ER-cisternae: one system links to both basal bodies and extends to the nucleus, the other two systems subtend the plasmamembrane on the left and right broad cell surfaces and extend to the posterior region of the cell. The flagellar apparatus is structurally identical to that previously described for zoospores ofFriedmannia israelensis and exhibits basal body displacement by one basal body diameter into the 11/5 o'clock direction, a non-striated distal connecting fiber, a cruciate microtubular root system lacking system I fibers and presence of a single system II fiber which connects the basal bodies with the nucleus and runs parallel to one of the ER-strands. The left flagellar roots (X-roots) are subtended by a complex set of amorphous and striated material that connects each left root with both basal bodies.—This study demonstrates the close systematic relationship between the phycobiontsTrebouxia andPseudotrebouxia and the generaFriedmannia, Pleurastrum, andMicrothamnion and supports recent classification schemes which place all these taxa into a single order separate from otherChlorophyta.
Dedicated to Prof. DrElisabeth Tschermak-Woess on the occasion of her 70th birthday. 相似文献
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H. -Dietmar Behnke 《Plant Systematics and Evolution》1977,128(3-4):227-235
The exine-sculpturing of pollen fromGisekia africana (Gisekiaceae),Limeum argute-carinatum (Molluginaceae) andHectorella caespitosa (Hectorellaceae) with supratectate spinulae and an anulopunctate tectum is in accordance with the manyCentrospermae investigated so far with the SEM. Pollen ofRhabdodendron macrophyllum and three species fromGyrostemonaceae do not exhibit these surface details. WhileRhabdodendron with a finely reticulate exine probably fits intoRutaceae, the unique columellaless exine ofGyrostemonaceae has no direct counterpart, neither inCentrospermae nor inCapparales, the two orders to which this family was allied. The genera ofGyrostemonaceae can be distinguished by different arrangements of minute pollen surface details.
Zur Skulptur der Pollen-Exine bei drei Centrospermen (Gisekia, Limeum, Hectorella), bei Gyrostemonaceen und Rhabdodendraceen相似文献
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Thomas Friedl 《Plant Systematics and Evolution》1989,164(1-4):145-159
Pyrenoid ultrastructure has been investigated from cultures of all 26 species ofTrebouxia with the aim of establishing pyrenoids as a taxonomic character. Different arrangements and forms of thylakoid lamellae within the pyrenoid matrix allow eight pyrenoid types to be distinguished. Each type is characteristic of a group of species. Thegigantea- andimpressa-type are similar, differing only in the form of the tubules: short, branched tubules mark thegigantea-type; ± long and straight invaginations theimpressa-type. Thearboricola-type is characterized by meandering pyrenoid membranes developing from lamellae parallel with each other in young autospores. Pyrenoids of thegelatinosa-type are traversed by thin parallel-arranged tubules. Few thylakoids with a curved profile are typical of theirregularis-type. Thecorticola-type is different from all others in having a distinct starch sheath closely connected with the pyrenoid matrix and no pyrenoglobuli being associated with the pyrenoid membranes. No true pyrenoids have been found inT. magna andT. erici. Within the chloroplast, they have indistinct areas with pyrenoglobuli, but without differentiated thylakoids. Pyrenoid morphology is stable in culture on different media as well as in phycobionts within lichen thalli. Comparing the pyrenoid of a lichenizedTrebouxia with that from cultured species, the identification of the phycobiont within the lichen thallus is possible, without the need of culturing the algae. This has been shown in species ofParmelia andHypogymnia. New aspects for the taxonomy and systematics ofTrebouxia are discussed.Dedicated to Prof. DrLothar Geitler on the occasion of the 90th anniversary of his birthday. 相似文献
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Leaf extracts of several taxa ofArgyranthemum (nanophaneroand chamaephytes endemic to the Macaronesian Islands) andChrysanthemum s. str. (therophytes of the West Mediterranean region) were subjected to polyacrylamide disc gel electrophoresis and analysis of peroxidase isoenzymes. The differences between the two genera are small; this points to their close affinity. The taxonomic subdivision ofChrysanthemum s. str. is confirmed. ForArgyranthemum the inclusion ofA. callichrysum andA. ochroleucum into sect.Ismelia is suggested.A. foeniculaceum may fit better into the otherwise isolated sect.Monoptera but somewhat approaches sect.Ismelia. Isoenzyme patterns inA. frutescens s. l. seem to reflect a geographical differentiation of the group on 5 Canary Islands. 相似文献
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The green algaTrebouxia aggregata (Archibald)Gärtner (Chlorellales) and the procaryotic blue-green alga (cyanobacterium)Gloeocapsa sanguinea (C. Agardh)Kütz. emend.Jaag (Chroococcales) are reported to be the phycobionts inEuopsis granatina (Sommerf.)Nyl. (Lichinaceae). The ultrastructure of the two organisms, studied in the lichen thallus, is described.
Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet. 相似文献
12.
Jing-Yu Li Yukio Agatsuma Takeshi Nagai Yoichi Sato Kazuya Taniguchi 《Journal of applied phycology》2009,21(2):215-224
The kelps Laminaria longissima and L. diabolica, belonging to the groups of L. angustata and L. japonica, respectively, differ greatly in their morphological characteristics although their geographical distributions overlap widely
along the eastern coast of Hokkaido. To clarify the interaction between the morphological and physiological characteristics
of the two species, and their link with environmental variables, hatchery-raised young sporophytes of L. longissima and L. diabolica collected from Hokkaido were cultivated simultaneously under similar conditions in Matsushima Bay, Miyagi, from January to
July 2004. Seasonal morphological characteristics, gross photosynthetic rate, nutrient uptake rates, and resource contents
were examined. The blade lengths of L. longissima and L. diabolica reached a maximum of 329.9 cm and 256.7 cm, respectively, in April to May, and decreased to 284.4 cm and 68.6 cm, respectively,
in July. The total elongation length of L. longissima (412.5 cm) was similar to that of L. diabolica (373.8 cm). However, the total erosion length of L. longissima (145.9 cm) was approximately half that of L. diabolica (302.9 cm). The gross photosynthetic rate and uptake rates of NH4-N, NO3-N, and PO4-P of the two species were similar. However, the carbon, nitrogen, and phosphorus contents were transferred and stored in
the whole blade tissues in the case of L. longissima, but in the meristem of L. diabolica from May to June. These results suggest that morphological differences are a response to different resource storage patterns.
The storage patterns of L. longissima and L. diabolica are likely to be genetically fixed characteristics, which have evolved in adaptation to the specific habitat environments
of the groups of L. angustata and L. japonica. The low water temperature and rich nutrients provided by the Oyashio Current are conducive to storage of resources in the
whole blade tissues and a large surface area retained for photosynthesis and nutrient uptake in the L. angustata group. Conversely, high temperature and poor nutrients, or large fluctuations in these parameters, provided by the Tsushima
Warm Current are more conducive to intensive storage of resources in the meristem for maturation and further growth in the
L. japonica group. L. diabolica retains the storage pattern of the L. japonica group but grows in regions affected by the Oyashio Current, allowing it to become the widest distributed Laminaria species. 相似文献
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Comparative studies in thePhysciaceae revealed that characters of the apical apparatus of asci differ between the various genera. Two major ascus types are observable in this family. They are found to correspond with certain ascospore types. 相似文献
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Zeller F. J. Heun M. 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,71(3):513-517
Summary In the progeny of a hybrid between monotelosomic line 3B of Chinese Spring wheat and Chinese Spring — Aegilops longissima ditelosomic addition line G a cytologically stable strain was selected consisting of 20 wheat chromosome pairs, one pair of telosomic chromosome 3BL and one pair of telosomic longissima chromosome G. Inoculating Chinese Spring — Aegilops longissima addition and substitution lines with ten different powdery mildew isolates, partial resistance was observed. The infection grade as well as the number of spores/cm2 leaf area were significantly reduced. 相似文献
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Maria Waha 《Plant Systematics and Evolution》1985,150(3-4):165-177
The four genera investigated show solitary sulcate pollen grains. The structure and sculpture of the sporoderm is very similar inBocageopsis andUnonopsis, and supports the close relationship of both genera; their flower morphology also is very similar. In contrast, the sporoderm ofEphedranthus, and especially that ofMalmea, is different in some characters and suggests more remote relationships; this is also confirmed by differences in flower morphology. Within this group of genera a distinct exine progression can be recognized from non-columellate (Malmea) to granular (Unonopsis guatterioides), further to somewhat irregularly (Bocageopsis, someUnonopsis species), and finally to very regularly columellate (Ephedranthus). The sculpture of the tectum varies from a reticulum with large lumina (Malmea) to one with small performations (Ephedranthus). Within theAnnonaceae the genusMalmea is among the most primitive in respect to pollen structure. The sulcus of the four genera is very large and runs over 1/3 of the pollen grain. It is characterized by a reduction of the exine and a bulgy thickening of the intine. 相似文献
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A new species, Hypocrella panamensis, is described from collections and cultures obtained on Barro Colorado Island, Panama. In order to aid in placement of this fungus, phylogenetic analyses were conducted using LSU (rDNA) sequences. Hypocrella panamensis is characterized by possessing pulvinate stromata with a Lecanicillium-like anamorphic state and superficial perithecia. Hypocrella panamensis consistently grouped in a clade containing Hypocrella nectrioides, H. phyllogena, and H. africana (100 % PP). Most species of Hypocrella possess Aschersonia or Hirsutella anamorphs. Hypocrella panamensis is unique in the genus Hypocrella in possession of a Lecanicillium-like anamorphic state. In its biological habit Hypocrella panamensis is similar to other species in Hypocrella in that it infects and degrades the scale insect, then grows superficially on nutrients that emerge to the plant surface through the stylet wound. 相似文献
20.
Lothar Geitler 《Plant Systematics and Evolution》1981,138(1-2):153-156
InCymbella the position of the chromatophore corresponds to the taxonomic differentiation into sections. The pyrenoid always shows the same right hand — left hand inclination. 相似文献