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1.
The epidermal structure of the five species of ferns, Arthromeriswallichiana (Spr.) Ching., Drymoglossum piloselloides (Prest.),Drynaria quercifolia (L.) J. Smith, Lepisorus nudus (Hook.)Ching. and Pyrrosia nuda (Gies.) Ching., has been investigated.Fifteen types of stomatal structures have been identified ofwhich copolo-desmocytic and coperi-desmocytic are new types.Four more possible stomatal structures: ccpolo-peri-, codesmo-polo-,codesmo-peri- and duplodesmocytic, are suggested. Localizationof starch, insoluble polysaccharides, protein and lipids hasbeen examined histochemically in the guard cells, subsidiarycells and epidermal cells. In Drynaria starch plastids and plastidscontaining both starch and protein are present in guard cells.Starch plastids are present in the subsidiary cells of all speciesexcept in Arthromeris, whereas, they are present in epidermalcells of only Drymoglossum and Lepisorus. Granular or amorphousinsoluble polysaccharides (other than starch) are present inguard cells of all the species, in the subsidiary cells of Arthromeris,Drynaria and Pyrrosia, and in the epidermal cells of Pyrrosia.Except in Pyrrosia lipids are present in the guard cells. Subsidiarycells of Drynaria and the epidermal cells of Arthromeris andDrynaria show lipid bodies. The presence of plasmodesmata andectodesmata is demonstrated in the epidermal cells of Drymoglossum.  相似文献   

2.
This is essentially a preliminary report on the revision ofsubgenus Lissachatina of the African land snail family Achatinidae.It extends the conchological revisionary work of J.C. Bequaert(1950) along the complementary line of comparative anatomicalstudies of the reproductive tracts. This is directed towardthe goal of a better understanding of phylo-geny in this family.Species emphasized are Achatina albopicta E.A. Smith,1878; A.allisa Reeve, 1849; A. fulica Bowdich, 1822; A. loveridgei Clench& Archer, 1930; A. zanzibarica Bourguignat, 1879, and thenew species A. eleanorae. Relegated tosynonymy are A. albicansPfeiffer, 1851; A. delorioli Bonnet, 1864; and A. iredalei Preston,1910. Tangible anatomical characters separate subgenera Lissachatinaand Achatina. A. capelloi Furtado, 1886; A. craveni E.A. Smith,1881; and A. connollyi Preston, 1912 are transferred from Lissachatinato Achatina s.s. Other transfers are in progress. (Received 26 September 1994; accepted 25 November 1994)  相似文献   

3.
对中国草螟亚科3个近缘属:带草螟属 Metaeuchromius Bleszynski、丽草螟属Euchromius Guenée和双带草螟属 Miyakea Marumo进行了研究。该3属在中国已记录12个种,包括带草螟属Metaeuchromius两新种:黄色带草螟 M. fulvusalis sp. Nov.,模式产地广西,与褐带草螟 M. circe Bleszynski近缘;灰色带草螟 M. grisalis sp. Nov.,模式产地浙江,与云南带草螟 M. yuennanensis (Caradja)近缘。对新种给出了描述、外生殖器特征图和与近缘种的比较。并提供了带草螟属中国已知种检索表。  相似文献   

4.
5.
中国菲寄蝇属分类研究(双翅目: 寄蝇科)   总被引:1,自引:0,他引:1  
赵建铭  陈小琳 《昆虫学报》2007,50(9):933-940
经研究发现中国菲寄蝇属现共有9种,其中包括4新种:金额菲寄蝇Phebellia aurifrons sp. nov.,褐粉菲寄蝇Ph. fulvipollinis sp. nov.,宽叶菲寄蝇Ph. latisurstyla sp. nov.和毛基节菲寄蝇Ph. setocoxa sp. nov.。我国新记录3种:叶蜂菲寄蝇Ph. clavellariae (Brauer & Bergenstamm),灰粉菲寄蝇Ph. glauca (Meigen)和拟灰粉菲寄蝇Ph. glaucoides Herting。本文除详细描述新种特征及绘制特征图外,还提供中国菲寄蝇属已知种类的分种检索表。  相似文献   

6.
CORNER  E. J. H. 《Annals of botany》1952,16(2):269-291
The genera Allantula (one sp.) and Parapterulicium (two spp.)are described from Brazil. The first has decumbent, cystidiateand unbranched fruit-bodies. The second has gloeocystidia anddichophyses, neither of which have yet been recorded in Pteruloidgenera. In the revision of Deflexula, ten species are recognized, fourbeing transferred from Mucronella and Pterula, and three beingdescribed as new, namely, D. major, D. mangiformu, and D. sulcispora.  相似文献   

7.
The genus Tricolia(Phasianellidae) in the Eastern Atlantic andMediterranean is reviewed on the bases of radular morphology,shell characters and polychromatism. The taxa included within the T. pullus (L.) group are not clearlyseparable and are treated as geographical subspecies:T. pulluspullus (L.), T. pullus picta (da Costa), T. pullus azorica (Dautzenberg),T. pullus canarica Nordsieck. The case of T. tenuis (Michaud)is problematic since it is clearly separable from sympatricT. pullus pullus in most parts of the Mediterranean but transitionalto T. pullus picta, towards the Atlantic. Other taxa are considered as having specific status since theyare consistently separable when found in sympatric populations.These include T. speciosa (Muhlfeldt), T. miniata (Monterosato),T. tingitana n.sp., T. petiti (Craven), T. nordsiecki (Talavera)and T. algoidea (Pallary). The last two species are stated forthe first time as belonging to the Phasianellidae. The genusEpheriella Pallary, based on T. algoidea, is synonymized withTricolia. (Received 6 April 1981;  相似文献   

8.
Ethylene biosynthesis in higher plants is regulated developmentallyand environmentally. To investigate the regulation of ACC synthasegene expression, the promoters of Arabidopsis ACS genes, AtACS4,AtACS5, and AtACS7, were fused to a GUS reporter gene, and therecombinant transgenes were introduced into Arabidopsis to producethree groups of AtACS::GUS transgenic plants. Histochemic andfluorometric study of these transgenic plants revealed thatpromoters of AtACS4, AtACS, and AtACS7 are all active in dark-germinatedseedlings. AtACS5 has the highest promoter activity in leavesof 2-week-old light-grown seedlings among the three AtACS genesstudied. In the mature leaves, AtACS4 and AtACS7 genes are expressedin both veins and areoles, whereas AtACS5 is expressed at ahigher level in the areoles and epidermal cells surroundingtrichomes. The promoter activities of all these AtACS genesare found in the reproductive organs. AtACS5 and AtACS7 arehighly expressed in petals, sepals, carpels, stamens, caulineleaves, inflorescence stems, and siliques, while AtACS4 expressionis undetectable in the petals of open flowers. All three AtACSgenes are expressed in root tissue. In the 2-week-old light-grownArabidopsis, the AtACS4 promoter is responsive to the planthormones IAA, ethylene, and ABA, and to darkness and wounding;the AtACS5 promoter to IAA, ABA, salt, high temperature, andwounding; and the AtACS7 promoter to GA3, ethylene, and ABA,and to darkness and salt. Low-temperature treatment abolishesthe darkness-induced AtACS7 gene expression, but not that ofAtACS4. Each AtACS gene has a unique expression profile duringgrowth and development. It appears that at any developmentalstage or any growth period of Arabidopsis, there is always amember of AtACS multigene family that is actively expressed. Key words: ACC synthase, Arabidopsis, ethylene, gene expression, GUS histochemical staining, reporter, stress treatments  相似文献   

9.
Extensive series of Amphidromus Albers, 1850 were collectedfrom low-altitude areas (30–500 m above sea level)in Thailand, Laos, Malaysia, Singapore and Indonesia between1993 and 2004. Data on shell colour, genital and spermatophoremorphology, and radular structure are presented. Five speciesof Amphidromus (Amphidromus) are reviewed, of which four occurin Thailand. Intraspecific variation between populations ofAmphidromus (Amphidromus) atricallosus (Gould, 1843) is considered;three subspecies are accepted and a new subspecies described.Subspecies of A. (A.) inversus (Müller, 1774) and A. (A.)schomburgki (Pfeiffer, 1861) are reconsidered, and a new subspeciesof the latter is described. A dichotomous key to the speciesand subspecies of Amphidromus (Amphidromus) in Thailand is provided. (Received 7 May 2004; accepted 31 March 2005)  相似文献   

10.
彩万志  王运兵 《昆虫学报》1998,41(-1):163-179
文中对国产的7种菱猎蝽作了比较详细的再描述与图示;短刺菱猎蝽Isyndus bre vispinus Breddin、毛翅菱猎蝽I .Lativentris Distant、毛足菱猎蝽I.Pilosipes Reuter被视为 有效种或独立种;I.Sinicus Hsiao et Ren 和I.Yunnananus Ren分别被认为是毛足菱猎蝽 I.Pilosipes Reuter和毛翅菱猎蝽I.Lativentris Distant的同物异名;短刺菱猎蝽为中国新纪录;所有种的阳茎构造均为首次报道;此外,还编制了该属中国已知种类分种检索表。  相似文献   

11.
Nolet  Bart A. 《Behavioral ecology》2002,13(4):571-574
Previous research has found that efficiency, or, more precisely,the foraging gain ratio (FGR), is a valid currency in foragingtheory when (1) there is a limit to the energy that can beassimilated by the forager and (2) a forager is trying to meetan energy requirement. The FGR is b/ (ccr), whereb is the rate of metabolizable energy intake, and c and crare the rates of energy expenditure while foraging and resting,respectively. Here I show that, when energy expenditure hasa cost besides energy, animals should also choose the optionwith the highest FGR when they are aiming at a given positivedaily gain. The next question is which gain they should aimfor? Researchers have shown that observed intake levels ofgrowing ruminants are close to the levels predicted by maximizationof the efficiency of oxygen utilization. This currency can be approximated by (BC + Cr) / C, where B is the daily metabolizable energy intake, and C and Cr are the total andbasal daily energy expenditures, respectively. By simulatinggrowth at different intake levels, I found that mass-specificoxygen consumption rate is indeed minimal at the observed intakelevels. This is the first study in which these efficiency measures(FGR and the efficiency of oxygen utilization) are combined.  相似文献   

12.
Eighteen species of the genus Oncaea, four of them polymorphic,have been collected from the inshore and offshore waters ofthe Lebanon. Three species are new additions to the Mediterraneanfaunal list, O.shmelevi, O.pumilis and O.rufa. The males ofthree poorly described species, O.bathyalis, O.ovalis and O.similis,the female of O.shmelevi and both sexes of O.tenella are redescribed.Oncaea media and O.mediterranea were the two most common representativesof the genus in the study area. Oncaea were most abundant inDecember and January and between March and May; they were mainlymesopelagic and oceanic. Many of the species recorded here havecosmopolitan distributions; some of the smaller ones are lesswell-known, but may prove in time to be as widespread as thelarger taxa.  相似文献   

13.
The habitat, diet, some reproductive and mortality factors forseveral shallow-water species of the boreal turrid genus Oenopotafrom the Puget Sound region were determined. All fed exclusivelyon tubicolous polychaetes. Oenopota fidicula was a dietary andhabitat generalise Oenopota elegans eats Schistocomus hiltoniand lives in areas of shell fragments. Oenopota excunata eatsTharyx multifilis and is a habitat generalist. Oenopota tabulataappears to be a dietary generalist, but lives only on or nearrocks. The widely-distributed species, O. levidensis, eats spionidpolychaetes, primarily Polydora species, or Owenia fusiformis,and is a habitat generalist. Feeding frequencies are low asare population densities; although O. levidensis sometimes exceeds15 animals m–2. Crabs are major predators upon turridsin some areas, but mortality causes are generally obscure. Spawningwas observed in four species, but only O. elegans and O. levidensishad viable larvae. Development takes 13–15 weeks, 6–7weeks in a capsule and 6–7 weeks as planktonic veligers.There are no nurse eggs. Settling was not observed. *Present mailing address: Bamfield Marine Station Bamfield,B.C. VOR 1B0 CANADA (Received 30 May 1982;  相似文献   

14.
Consider a set of baseline predictors X to predict a binaryoutcome D and let Y be a novel marker or predictor. This paperis concerned with evaluating the performance of the augmentedrisk model P(D = 1|Y,X) compared with the baseline model P(D= 1|X). The diagnostic likelihood ratio, DLRX(y), quantifiesthe change in risk obtained with knowledge of Y = y for a subjectwith baseline risk factors X. The notion is commonly used inclinical medicine to quantify the increment in risk predictiondue to Y. It is contrasted here with the notion of covariate-adjustedeffect of Y in the augmented risk model. We also propose methodsfor making inference about DLRX(y). Case–control studydesigns are accommodated. The methods provide a mechanism toinvestigate if the predictive information in Y varies with baselinecovariates. In addition, we show that when combined with a baselinerisk model and information about the population distributionof Y given X, covariate-specific predictiveness curves can beestimated. These curves are useful to an individual in decidingif ascertainment of Y is likely to be informative or not forhim. We illustrate with data from 2 studies: one is a studyof the performance of hearing screening tests for infants, andthe other concerns the value of serum creatinine in diagnosingrenal artery stenosis.  相似文献   

15.
The taxonomy of South African Siphonaria is reviewed. We concludethat nine species are valid. These are: S. anneae Tomlin, 1944;S. capensis Quoy & Gaimard, 1833; S. compressa Allanson,1959; S. concinna Sowerby, 1824; S. dayi Allanson, 1959; S.nigerrima Smith, 1903; S. oculus Krauss, 1848; S. serrata (Fischer,1807) and S. tenuicostulata Smith, 1903. Of these, Siphonarianigerrima Smith, 1903, has been incorrectly synonymized withSiphonaria carbo Hanley, 1858, which is not present on SouthAfrican shores. S. aspera Krauss, 1848 is reduced to a juniorsynonym of S. Serrata (Fischer, 1807). Shell characteristicsand mode of larval development are described for these nineSouth African species. All species deposit benthic egg massesand development may be either planktonic with swimming veligerlarvae (S. capensis, S. concinna and S. oculus) or direct, withcrawling larvae emerging from the eggs (S. anneae, S. compressa,S. dayi, S. nigerrima, S. serrata and S. tenuicostulata). (Received 20 November 1992; accepted 24 January 1994)  相似文献   

16.
COLLINSON  M. E. 《Annals of botany》1980,46(5):603-632
The nine extant genera within the Nymphaeaceae s l (Water Lilies)are shown to be separable from one another on the basis of seedmorphology In particular, epidermal detail, vertical sectionof the testa and relative position of the micropyle and hilumare diagnostic for each genus These features are consideredin connection with current systematic treatments of this familyFossil seeds are reviewed at the generic level and many of theseeds previously assigned to Brasenia ovula (Brong ) Reid andChandler are shown to belong to an extinct genus of Nymphaeaceaeintermediate between the currently accepted families Cabombacaceaeand Nymphaeaceae s s They are redescribed as Sabrenia chandleraegen et sp nov. The British Tertiary fossils Brasenia spinosaChandler, Palaeonymphaea eocenica Chandler emend and ?Nymphaealiminis sp nov are described Fossil material of Carpolithesovulum Brongniart 1822a, Brasenia victoria (Casp ) Weberbauer1893, B teumeri Kirchheimer 1935, B tenuicostata Nikitin 1965and Nymphaea arethusae Grambast 1962 has been studied for comparativepurposes The use of ‘?’ before the extant genericname is advocated when all features of a fossil indicate thatit may be placed in a living genus but when certain additional,critical features of the living genus are lacking on the fossil. Nymphaeaceae, water lilies, seeds, palaeobotany, Tertiary, Sabrenia chandlerae gen et sp nov Nymphaea liminis sp nov, Brasenia ovula  相似文献   

17.
漠甲亚科八种幼虫记述(鞘翊目:拟步甲科)   总被引:3,自引:0,他引:3  
于有志  任国栋 《昆虫学报》1995,38(3):347-354
漠甲亚科Pimcliinae是一类广布于古北区的耐旱沙漠昆虫,幼虫在沙土内发育,危害 植物嫩芽和根部,经济意义较大。本文记述了采自宁夏、甘肃、内蒙古和新疆的8个种,即多毛扁漠甲、谢氏宽漠甲、泥脊漠甲[1]、洛氏脊漠甲[1]、光滑胖漠甲[1]、蒙古漠王、谢氏宽漠王和大宽漠王的幼虫,并给出它们的检索表。幼虫标本保存于宁夏农学院。  相似文献   

18.
Protein-O-glycosylation in yeast: protein-specific mannosyltransferases   总被引:11,自引:2,他引:9  
S.cerevisiae contains at least six genes (PMT1–6) fordolicholphosphate-D-mannose: protein-O-D-mannosyltransferases.The in vivo mannosylation of seven O-mannosylated yeast proteinshas been analyzed in a number of pmt mutants. The results clearlyindicate that the various protein O-mannosyltransferases havedifferent specificities for protein substrates. Five of theproteins tested (chitinase, a-agglutinin, Kre9p, Bar1p, Pir2p/hsp150)are mainly underglycosylated in pmt1 and pmt2 mutants, wherebyqualitative differences exist among the various proteins. Twoof the O-mannosylated proteins (Ggp1p and Kex2p) are not atall affected in pmt1 and pmt2 mutants but are clearly underglycosylatedwhen PMT4 is mutated. Although the PMT4 gene product is shownto be responsible for O-mannosylating a Ser-rich region of Ggp1pin vivo, a penta-seryl-peptide is not an in vitro substratefor this transferase. A PMT3 mutation does affect O-manno-sylationof chitinase only in the genetic background of a pmt1pmt2 doublemutation, indicating that PMT1 and PMT2 can compensate for adeleted PMT3 gene. dolichol-phosphate PMT gene family protein glycosylation S. cerevisiae  相似文献   

19.
20.
The enormous metabolic plasticity of plants allows detoxificationof many harmful compounds that are generated during biosyntheticprocesses or are present as biotic or abiotic toxins in theirenvironment. Derivatives of toxic compounds such as glutathioneconjugates are moved into the central vacuole via ATP-bindingcassette (ABC)-type transporters of the multidrug resistance-associatedprotein (MRP) subfamily. The Arabidopsis genome contains 15AtMRP isogenes, four of which (AtMRP1, 2, 11 and 12) clustertogether in one of two major phylogenetic clades. We isolatedT-DNA knockout alleles in all four highly homologous AtMRP genesof this clade and subjected them to physiological analysis toassess the function of each AtMRP of this group. None of thesingle atmrp mutants displayed visible phenotypes under controlconditions. In spite of the fact that AtMRP1 and AtMRP2 hadbeen described as efficient ATP-dependent organic anion transportersin heterologous expression experiments, the contribution ofthree of the AtMRP genes (1, 11 and 12) to detoxification ismarginal. Only knockouts in AtMRP2 exhibited a reduced sensitivitytowards 1-chloro-2,4-dinitrobenzene, but not towards other herbicides.AtMRP2 but not AtMRP1, 11 and 12 is involved in chlorophylldegradation since ethylene-treated rosettes of atmrp2 showedreduced senescence, and AtMRP2 expression is induced duringsenescence. This suggests that AtMRP2 is involved in vacuolartransport of chlorophyll catabolites. Vacuolar uptake studiesdemonstrated that transport of typical MRP substrates was reducedin atmrp2. We conclude that within clade I, only AtMRP2 contributessignificantly to overall organic anion pump activity in vivo.  相似文献   

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