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THIERRY BACKELJAU CARLOS P. DE BRITO REGINA M. TRISTÃO DA CUNHA ANTONIO M. FRIAS MARTINS LUC DE BRUYN 《Biological journal of the Linnean Society. Linnean Society of London》1992,46(1-2):131-143
Thirty specimens of Arion intermedins from Flores (and Corvo) were electrophoretically (PAGE) assayed for 11 enzymes, yielding information about 14 putative loci in two colour morphs of this species. One of these colour variants was tentatively identified as A. pascalianus (P morph). Except for the Mdh locus, all loci in A. intermedins sensu lato from Flores were monomorphic. Mdh , however, was diallelic for Mdh100 and Mdh122 . This latter electromorph was absent in A. intermedins sensu stricto from Flores, but present in the P morph and A. intermedins from Belgium. As a consequence A. intermedins sensu lato from Flores consists of two genetic strains defined by the Mdh alleles. The genetic identity between these strains (7) is 0.929. The genetic identity between the P morph and A. intermedins sensu stricto in Flores is 0.951, while between the P morph and Belgian A. intermedins it is 0.973. These values suggest that the supposed A. pascalianus from Flores is only a colour morph of A. intermedins. This paper also provides the first published record of this species from the island of Corvo. 相似文献
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Karyology of some Brazilian species of Alismataceae 总被引:1,自引:0,他引:1
JÚLIA Y. COSTA ELIANA R. FORNI-MARTINS 《Botanical journal of the Linnean Society. Linnean Society of London》2003,143(2):159-164
The family Alismataceae ( sensu Cronquist) comprises 11 genera and 75 species of aquatic and semiaquatic herbs. In Brazil, only the two most speciose genera, Echinodorus Rich. ex Engelm. and Sagittaria L., are present. The chromosome number 2 n = 22 is common to all species. We present karyotypes for eight species, together with their asymmetry index (TF%) and total chromatin length (TCL). All karyotypes have high karyotypic asymmetry and TCL, due to their large and mostly acrocentric chromosomes. The chromosomal evolution of the Alismatidae group is discussed. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 159−164. 相似文献
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ELIANA E. BONTTI † JOSEPH P. DECANT † SETH M. MUNSON † MARK A. GATHANY † AGNIESZKA PRZESZLOWSKA† MICHELLE L. HADDIX †‡ STEPHANIE OWENS INGRID C. BURKE †‡ WILLIAM J. PARTON ‡ MARK E. HARMON§ 《Global Change Biology》2009,15(5):1356-1363
One of the major concerns about global warming is the potential for an increase in decomposition and soil respiration rates, increasing CO2 emissions and creating a positive feedback between global warming and soil respiration. This is particularly important in ecosystems with large belowground biomass, such as grasslands where over 90% of the carbon is allocated belowground. A better understanding of the relative influence of climate and litter quality on litter decomposition is needed to predict these changes accurately in grasslands. The Long‐Term Intersite Decomposition Experiment Team (LIDET) dataset was used to evaluate the influence of climatic variables (temperature, precipitation, actual evapotranspiration, and climate decomposition index), and litter quality (lignin content, carbon : nitrogen, and lignin : nitrogen ratios) on leaf and root decomposition in the US Great Plains. Wooden dowels were used to provide a homogeneous litter quality to evaluate the relative importance of above and belowground environments on decomposition. Contrary to expectations, temperature did not explain variation in root and leaf decomposition, whereas precipitation partially explained variation in root decomposition. Percent lignin was the best predictor of leaf and root decomposition. It also explained most variation in root decomposition in models which combined litter quality and climatic variables. Despite the lack of relationship between temperature and root decomposition, temperature could indirectly affect root decomposition through decreased litter quality and increased water deficits. These results suggest that carbon flux from root decomposition in grasslands would increase, as result of increasing temperature, only if precipitation is not limiting. However, where precipitation is limiting, increased temperature would decrease root decomposition, thus likely increasing carbon storage in grasslands. Under homogeneous litter quality, belowground decomposition was faster than aboveground and was best predicted by mean annual precipitation, which also suggests that the high moisture in soil accelerates decomposition belowground. 相似文献
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Revisiting Coptotermes (Isoptera: Rhinotermitidae): a global taxonomic road map for species validity and distribution of an economically important subterranean termite genus 下载免费PDF全文
THOMAS CHOUVENC HOU‐FENG LI JAMES AUSTIN CHRISTIAN BORDEREAU THOMAS BOURGUIGNON STEPHEN L. CAMERON ELIANA M. CANCELLO REGINALDO CONSTANTINO ANA MARIA COSTA‐LEONARDO PAUL EGGLETON THEODORE A. EVANS BRIAN FORSCHLER J. KENNETH GRACE CLAUDIA HUSSENEDER JAN KŘEČEK CHOW‐YANG LEE TIMOTHY LEE NATHAN LO MATTHEW MESSENGER AARON MULLINS ALAIN ROBERT YVES ROISIN RUDOLF H. SCHEFFRAHN DAVID SILLAM‐DUSSÈS JAN ŠOBOTNÍK ALLEN SZALANSKI YOKO TAKEMATSU EDWARD L. VARGO AKINORI YAMADA TSUYOSHI YOSHIMURA NAN‐YAO SU 《Systematic Entomology》2016,41(2):299-306
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Acclimation of metabolism to light in Arabidopsis thaliana: the glucose 6‐phosphate/phosphate translocator GPT2 directs metabolic acclimation 下载免费PDF全文
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SYNOPSIS. In cultures of Trypanosoma conorhini the authors have detected "cyst-like bodies" (CLBs) that, in the initial phase, have the appearance of 2 or more overgrown crithidiae fused together; after disorganization of the internal structure of the parent flagellates and division of their organelles, new crithidiae are formed within the CLB. The wall of the CLB consists of an irregularly thick layer of cytoplasm surrounded by the periplast of the parent flagellates and a true cystic membrane is not evident. The daughter crithidiae eventually escape from the CLB leaving the periplast and other residues of the parent flagellates. It is suggested that this represents a method of reproduction entirely different from binary or multiple fission, that is probably common to other trypanosomes of the Section STERCORARIA, and that it may provide for genetic exchange even if it is not a true sexual process. 相似文献
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DAVID SILLAM‐DUSSÈS ETIENNE SÉMON ALAIN ROBERT ELIANA CANCELLO MICHAEL LENZ IRENA VALTEROVÁ CHRISTIAN BORDEREAU 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(1):20-27
In the present study, trail pheromone blends are identified for the first time in termites. In the phylogenetically complex Nasutitermitinae, trail‐following pheromones are composed of dodecatrienol and neocembrene, the proportions of which vary according to species, although neocembrene is always more abundant than dodecatrienol (by 25–250‐fold). Depending on species, termites were more sensitive to dodecatrienol or to neocembrene but the association of both components always elicited significantly higher trail following, with a clear synergistic effect in most of the studied species. A third component, trinervitatriene, was identified in the sternal gland secretion of several species, but its function remains unknown. The secretion of trail pheromone blends appears to be an important step in the evolution of chemical communication in termites. The pheromone optimizes foraging, and promotes their ecological success. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 20–27. 相似文献
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ROSA M. T. HAIDO MANUEL J. G. ESTEVES ELIANA BARRETO-BERGTER 《The Journal of eukaryotic microbiology》1992,39(5):609-612
ABSTRACT Changes in the cell surface carbohydrates of Trypanosoma cruzi epimastigotes induced by Amphotericin B (AmB) were assessed by chemical methods and by agglutination assay employing a panel of highly purified lectins of various sugar specificities, Escherichia coli K12 with mannose-sensitive fimbriae was also used as an agglutination probe. Amphotericin B caused a decrease in the total carbohydrate content of all glycoconjugate fractions isolated. Exposure to AmB strongly affected the mannose/galactose ratio (1:5) in the CHCI3/methanol/H2O soluble fraction. These sugars in 1.4:1 ratio were the major hexose components of control cells. The decrease in the mannose content (48 to 15%) after AmB treatment agrees with the marked decrease in the T. cruzi cell surface receptors for fimbriated E. coli K12. Also, an increase in the galactose content (74%) as compared with control cells (34%) is in agreement with the peanut agglutinin and Euonymus europaeus lectins agglutination results. Differences in the cell surface carbohydrates induced by AmB could be associated with alterations in the membrane structure and organization. 相似文献