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  • Pisum  (22)
  • Drosophila melanogaster  (17)
  • Springer  (39)
  • American Institute of Physics
  • 2005-2009
  • 1980-1984  (39)
  • 1925-1929
  • 1980  (39)
Collection
Keywords
Publisher
  • Springer  (39)
  • American Institute of Physics
Years
  • 2005-2009
  • 1980-1984  (39)
  • 1925-1929
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Development genes and evolution 188 (1980), S. 127-132 
    ISSN: 1432-041X
    Keywords: Pole cell isolation ; Maternal effect mutants ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary A procedure for pole cell isolation has been developed that takes advantage of theDrosophila melanogaster maternal effect mutantmat(3) 1. Embryos derived from homozygousmat(3)1 mothers form exclusively pole cells. By outcrossing we could substantially increase the expressivity of the original mutant stock. We further introduced theTM8 balancer chromosome, which carries the dominant temperature sensitive mutationDTS-4. This allows the accumulation of large homozygousmat(3) 1 fly populations by eliminating the heterozygous flies at the restrictive temperature. Early embryos were mechanically fragmented and the cells were isolated by means of metrizamide step gradients. The isolated cells were demonstrated to exhibit the various ultrastructural and histochemical characteristics of pole cells. The isolated cells were transplanted into genetically marked host embryos. The germ line mosaics that were obtained indicate that the isolated cells represent functional pole cells. Proteins synthesized by the isolated pole cells during short term in vitro labelling with35S-methionine were compared to the proteins synthesized by blastoderm cells fromOregon-R embryos. At least one protein could be demonstrated in the pole cell samples that is not synthesized byOregon-R blastoderm cells. The method allows a fast and gentle isolation of highly enriched pole cell populations which are a prerequisite for the biochemical analysis of germ cell determination and differentiation.
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  • 2
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    Planta 148 (1980), S. 437-443 
    ISSN: 1432-2048
    Keywords: Chloroplasts (number, DNA) ; DNA (chloroplast) ; Pisum ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts were prepared from pea (Pisum sativum L.) leaves throughout development and their contents spread in a monolayer to determine the number of chloroplasts per cell. This approach permitted the rapid analysis of more than 100 cells at each stage of development. The average number of chloroplasts per cell increased from 24±10 to 64±20 during greening and expansion of the first true foliage leaves; all cells containing chloroplasts apparently increase their chloroplast number. A parallel increase in the amount of DNA per nucleus was not observed. As the leaves senesced the chloroplast number gradually decreased to 44±12. We have correlated these changes with our previous results on the percentage of chloroplast DNA per cell. Chloroplast multiplication resulted in a 2.7-fold dilution (from 272 to 102) of the number of copies of the chloroplast DNA molecule per plastid.
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  • 3
    ISSN: 1432-2048
    Keywords: Ammonia assimilation ; Glutamate dehydrogenase ; Mitochondria ; Photorespiratory ammonia production ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The ability of isolated pea-shoot mitochondria conditioned to incorporate ammonia into glutamate to reassimilate endogenously produced ammonia from glycine transformation was investigated. In the presence of 1 mM to 20 mM glycine less than 15% of the ammonia liberated was found to be incorporated into glutamate. Thus, a prominent role of mitochondrial glutamate dehydrogenase in the reassimilation of intramitochondrially produced ammonia can be excluded.
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  • 4
    ISSN: 1432-2048
    Keywords: Phytochrome ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The red-light(R)-absorbing form of phytochrome (Pr) was detected spectrophotometrically in a 20,000 g particulate fraction prepared from a 1,000 g supernatant fraction from epicotyl tissue of pea (Pisum sativum L.) seedlings grown in the dark and only briefly exposed to dim green light. The difference spectrum of phytochrome in this fraction was essentially the same as that of soluble phytochrome from the same tissue. When the non-irradiated 20,000 g particulate fraction was incubated in the dark at 25° C, an absorbance change (decrease) of Pr after actinic red irradiation was found only in the far-red (FR) region. When the 20,000 g particulate fraction was irradiated with R and then incubated in the dark, the FR-absorbing form of phytochrome (Pfr) disappeared spectrally at a rate about half that in the soluble fraction, and the difference spectrum of the Pr which became detectable after dark incubation of the 20,000 g particulate fraction was markedly distorted. In contrast, Pfr in a 20,000 g particulate fraction prepared from tissues irradiated with R did not change optically during dark incubation at 25° C for 60 min, while Pfr in the soluble fraction from the same tissue disappeared in the dark. No dissociation of either Pr or Pfr from the 20,000 g particulate fraction was indicated during a 60-min dark incubation at 25° C, but Pfr in a 20,000 g particulate fraction prepared in vitro from R-irradiated 1,000 g supernatant fraction in the presence of CaCl2 disappeared spectrally and the difference spectrum of Pr in the 20,000 g particulate fraction became quite distorted during the dark incubation.
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  • 5
    ISSN: 1432-2048
    Keywords: Auxin transport ; Cell length ; Light and auxin transport ; Phaseolus ; Pisum ; Transport (auxin)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The putative auxin-transporting cells of the intact herbaceous dicotyledon are the young, differentiating vascular elements. The length of these cells was found to be considerably greater in dwarf (Meteor) than in tall (Alderman) varieties ofPisum sativum L., and to be greater in etiolated than in light-grown plants ofP. sativum cv Meteor andPhaseolus vulgaris L. cv Mexican Black. Under given light conditions during transport these large differences in cell length did not influence the shapes of the transport profiles or the velocity of transport of14C-labelled indol-3yl-acetic acid (IAA) applied to the apical bud. However, in both etiolated and light-grown bean and dwarf pea plants the velocity of transport in darkness was ca. 25% lower than that in light. Under the same conditions of transport velocities in bean were about twice those observed in the dwarf pea. Exposure to light during transport increased the rate of export of14C from the labelled shoot apex in green dwarf pea plants but not in etiolated plants. The light conditions to which the plants were exposed during growth and transport had little effect on the rates of uptake of IAA from the applied solutions. The results indicate that the velocity of auxin transport is independent of the frequency of cell-to-cell interfaces along the transport pathway and it is suggested that in intact plants auxin transport is entirely symplastic.
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  • 6
    ISSN: 1432-2048
    Keywords: Cell-free translation ; Lectin ; Long-lived mRNA ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Extracts prepared from dry pea (Pisum sativum, L; cv oberon) primary axes translate efficiently their endogenous messengers in an in vitro protein synthesizing system. The native long-lived messengers are biologically fully active and direct the synthesis of a whole range of polypeptides with MW ranging up to 130,000. About 0.5% of the total in vitro synthesized polypeptides are recovered in the immunoprecipitate obtained with pea lectin antiserum. Since about one-fourth of the radioactivity in the immunoprecipitate comigrates with authentic pea lectin it is concluded that about 0.1% of the long-lived messengers code for the lectin.
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  • 7
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    Planta 149 (1980), S. 427-432 
    ISSN: 1432-2048
    Keywords: Chloroplast envelope ; Light and chloroplast envelope ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Glutaraldehyde fixation in 0.33 M sorbitol without any buffer reveals changes in the staining properties of the envelopes of chloroplasts of pea plants kept in the light or in the dark prior to fixation. After dark pretreatment the outer double membrane of the chloroplast does not adsorb heavy metals, resulting in a “white” unstained rim instead of the usual membrane. All other membranes of the cell, including chloroplast grana, are not affected and stain normally. Light pretreatment of the plants allows the usual staining of the outer membrane of the chloroplats. Fixation carried out in the medium usually used to isolate intact CO2 fixing chloroplasts (sorbitol+buffer+ions) reverses the above process and results in unstained envelopes of chloroplasts from preilluminated leaves, while the envelopes of chloroplasts from leaves kept in the dark stain normally. Glutaraldehyde-fixed chloroplats isolated from preilluminated leaves show a very basic isoelectric point during electrofocusing, while fixed chloroplasts from predarkened tissue exhibit an isoelectric point at about pH 7.
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  • 8
    ISSN: 1432-2048
    Keywords: Embryo culture ; Enzyme-linked immunosorbent assay (ELISA) ; Legumin ; Pisum ; Protein (storage) ; Storage protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A highly sensitive immunoassay has been used for the detection of a major storage protein, legumin, in embryos of Pisum sativum L.; with this technique nanogram quantities could be measured. In the two varieties tested, legumin could be detected in embryos in vivo, when they had attained a fresh weight of 2·10-3 g and 3·10-3 g, respectively. Contrary to earlier claims, embryos cultured in vitro were shown to be capable of initiating legumin synthesis. This capacity to initiate legumin synthesis was confirmed by two-dimensional isoelectric focusing-electrophoresis and fluorography; embryos harvested before initiation of legumin synthesis and cultured in radioactive medium were shown to have synthesized legumin subunits. The amounts of legumin and total protein synthesized per unit fresh weight were consistently greater in vitro than in equivalent embryos grown in vivo.
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  • 9
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    Planta 150 (1980), S. 431-434 
    ISSN: 1432-2048
    Keywords: Auxin transport ; Electric current ; Pisum ; Potential gradients
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract When a d.c. potential of 9.0 V was applied to the stem of intact pea seedlings (Pisum sativum L. cv. Meteor and cv. Alderman) via 10 mM KCl-soaked filter paper electrodes placed ca. 50 mm apart the stem passed a steady current of 15–20 μA (resistance ca. 100 kΩ cm-1). The basipetal transport of [1-14C]IAA applied to the apical bud was completely inhibited over the portion of the stem through which current flowed and 14C-labelled compounds accumulated in the vicinity of the upper electrode. The inhibition of transport was independent of the polarity of the applied potential. The basipetal transport of IAA in the stem above the electrode was not affected. Labelled auxin accumulated at the upper electrode both as unchanged IAA and as a compound tentatively identified as indol-3yl-acetyl aspartic acid (IAAsp). These compounds were only slowly remobilised when the current was interrupted. However, the ability of the transport system to move freshly-applied IAA was rapidly and fully restored when the potential was removed. No injury to the plant was detected after maintaining a current flow for up to 72 h. No leakage of 14C-labelled compounds into the KCl solution bathing the electrodes was detected.
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  • 10
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    Planta 147 (1980), S. 444-450 
    ISSN: 1432-2048
    Keywords: Abscisic acid ; Auxin ; Cytokinin ; Decapitation ; Fruit-set ; Gibberellin ; Parthenocarpy ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The influence of removing the apical shoot and different leaves above and below the flower on the fruit-set of unpollinated pea ovaries (Pisum sativum L. cv. Alaska) has been studied. Unpollinated ovaries were induced to set and develop either by topping or by removing certain developing leaves of the shoot. Topping had a maximum effect when carried out before or on the day of anthesis, and up to four consecutive ovaries were induced to set in the same plant. The inhibition of fruit-set was due to the developing leaves and not to the apex. The third leaf above the first flower, which had a simultaneous development to the ovary, had the stronger inhibitory effect on parthenocarpic fruit-set. The application of different plant-growth regulators (indoleacetic acid, naphthylacetic acid, 2,4-dichlorophenoxyacetic acid, gibberellic acid, benzyladenine and abscisic acid) did not mimic the negative effect of the shoot.
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  • 11
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    Planta 147 (1980), S. 451-456 
    ISSN: 1432-2048
    Keywords: Abscisic acid ; Auxin ; Fruit-set ; Gibberellin ; Parthenocarpy ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The development of parthenocarpic fruits of Pisum sativum L. cv. Alaska was induced by the application of different plant-growth regulators in aqueous solution to the emasculated ovaries in untopped plants. At least one compound in each of the groups of auxins (2,4-dichlorophenoxyacetic acid), cytokinins (benzyladenine), and gibberellins (gibberellic acid) was found active. Gibberellic acid (GA3), however, was the only substance which produced pods similar to those of fruits with seeds. The length of the pods obtained by GA3 was a linear function of the logarithm of the concentration of GA3 in the solution. The effect of GA3 (at a concentration which produced 50% of the maximum pod length) was enhanced by a simultaneous application of 2,4-dichlorophenoxyacetic acid. Abscisic acid (ABA) counteracted the effect of GA3 and of topping. The results suggest that gibberellins and ABA may exert a major regulatory control in natural fruit-set. Peas can be used for the assay of fructigenic activity and is an advantageous material for the study of the mode of action of gibberellins on fruit-set.
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  • 12
    ISSN: 1432-2048
    Keywords: Legumin ; Pisum ; Protien synthesis ; RNA ; Storage protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Evidence is presented to show that legumin, the major storage protein in Pisum, is synthesised in vitro by the wheat germ and reticulocyte lysate systems, from polyribosomes and mRNA isolated from developing pea seeds. While legumin isolated from mature pea seeds consists of 40,000 and 20,000 MW subunits, the in vitro legumin is synthesised as a 60,000 MW precursor consisting of covalently linked 40,000 and 20,000 MW subunits. The implications of these findings are discussed in relationship to studies with other systems.
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  • 13
    ISSN: 1432-2048
    Keywords: Pisum ; Polyribosomes ; Post translational modifications ; Protein synthesis ; Storage proteins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Polypeptide material has been immunoprecipitated by antivicilin antibodies from translation products of polyribosomes and poly(A)-rich RNA isolated from developing seeds of Pisum sativum in the wheat germ and reticulocyte lysate cell-free synthesis systems. Analysis of this material by SDS-PAGE shows it to consist of three bands, of molecular weights 70,000, 50,000 and 47,000. The in vitro vicilin polypeptides of 70,000 and 50,000 mol. wt. have been shown to be very similar to the 70,000 and 50,000 mol. wt. subunits of vicilin by specific immunoprecipitation, and behaviour on treatment with cyanogen bromide and trypsin. The 50,000 mol. wt. in vitro vicilin polypeptide contains no significant extra sequence compared to the 50,000 mol. wt. vicilin subunit. The 47,000 mol. wt. in vitro vicilin polypeptide has no corresponding subunit in vicilin from mature seeds, but a 47,000 mol. wt. subunit is present in vicilin isolated from developing seeds. Comparison of translation products from polysomes isolated from seeds at middle and late stages of development shows that synthesis of the 50,000 and 47,000 mol. wt., but not 70,000 mol. wt. polypeptides is very much reduced at late stages of development. These results are discussed with reference to the nature of the vicilin fraction.
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  • 14
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    Planta 148 (1980), S. 346-353 
    ISSN: 1432-2048
    Keywords: Chromatin ; DNA ; Germination (embryos) ; Nucleosomes ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Micrococcal nuclease digestion of chromatin from ungerminated and 48 h-germinated pea embryos yields DNA fragments which are multiples of basic units of 194–195 base pairs. Extensive digestion produces a core particle of 145 base pairs. Deoxyribonuclease I gives rise to fragments which are multiples of 10 bases upon analysis on denaturing gels. These values are comparable with those found for other plant materials. These results indicate that gross changes in nucleosomal organization do not accompany the onset of germination.
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  • 15
    ISSN: 1432-2048
    Keywords: Gibberellin metabolism ; Pisum ; Seeds (gibberellin metabolism)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The metabolism of GA29 during seed maturation in Pisum sativum cv. Progress No. 9 was further investigated. [17-13C1]GA29 was metabolised to a GA-catabolite (structure 3), with incorporation of the [13C] label from the GA29 substrate into the GA-catabolite being demonstrated by GC-MS. Quantitation of the GA-catabolite using GC-MS was achieved by adding GA-catabolite, labelled with [18O], to seed extracts as an internal standard. At least 50% conversion of [13C1]GA29 to [13C1]GA-catabolite was demonstrated with the build up of exogenous [13C1]GA-catabolite strictly paralleling the accumulation of native GA-catabolite. These results strongly suggest that conversion of GA29 to the GA-catabolite is a natural metabolic step occurring during the final stages of seed maturation. 25 μg per seed of native GA-catabolite was recorded in 37 day old seeds. Some problems encountered in the analysis of extracts containing the GA-catabolite are discussed briefly.
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  • 16
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    Planta 148 (1980), S. 7-16 
    ISSN: 1432-2048
    Keywords: Glutamate dehydrogenase ; Glutamate formation ; Mitochondria ; Isoenzyme patterns ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A 2–8-fold increase in the activity of glutamate dehydrogenase (GDH), accompanied by an alteration of the GDH isoenzyme pattern, was observed in detached pea shoots floated on tap water (preincubated shoots). Sugars supressed the process, whereas NH + 4 and various metabolites as well as inhibitors of energy metabolism and protein synthesis were ineffective. The subcellular distribution pattern revealed evidence that the GDH isoenzymes are exclusively located in the mitochondrial matrix. The alterations in GDH activity occurring in preincubated shoots are restricted to the mitochondria. An experimental device suitable for studying the GDH function in isolated intact mitochondria has been established. Using [14C] citrate as the carbon source and hydrogen donor, the mitochondria synthesized considerable amounts of glutamate upon addition of NH + 4 . The rates of glutamate formation in dependency of increasing NH + 4 levels follow simple Michaelis-Menten kinetics. Half-saturation concentrations of NH + 4 of 3.6±1.2 mM; 1.9±0.06 mM and 1.6±0.1 mM were calculated for the mitochondria isolated from pea shoots, roots, and preincubated shoots, respectively. The results are discussed in relation to the possible role of GDH in NH+/4 assimilation at elevated intracellular NH+/4 levels.
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  • 17
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    Planta 150 (1980), S. 153-157 
    ISSN: 1432-2048
    Keywords: Manganese ; Pisum ; Superoxide dismutase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A manganese-containing superoxide dismutase (EC 1.15.1.1) was purified to homogeneity from a higher plant for the first time. The enzyme was isolated fromPisum sativum leaf extracts by thermal fractionation, ammonium sulfate salting out, ion-exchange and gel-filtration column chromatography, and preparative polyacrylamide gel electrophoresis. Pure manganese superoxide dismutase had a specific activity of about 3,000 U mg-1 and was purified 215-fold, with a yield of 1.2 mg enzyme per kg whole leaf. The manganese superoxide dismutase had a molecular weight of 94,000 and contained one g-atom of Mn per mol of enzyme. No iron and copper were detected. Activity reconstitution experiments with the pure enzyme ruled out the possibility of a manganese loss during the purification procedure. The stability of manganese superoxide dismutase at-20°C, 4°C, 25°C, 50°C, and 60°C was studied, and the enzyme was found more labile at high temperatures than bacterial manganese superoxide dismutases and iron superoxide dismutases from an algal and bacterial origin.
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  • 18
    ISSN: 1432-2048
    Keywords: mRNA ; Protein synthesis ; Pisum ; Seeds (translation) ; Translation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Extracts from the primary axes of dry pea (Pisum sativum L.) seeds are able to perform an initiation-dependent translation of exogenous mRNA. SDS polyacrylamide gel electrophoresis of the products synthesized under direction of alfalfa mosaic virus RNA (AMV-RNA) and tobacco mosaic virus RNA (TMV-RNA) shows that the fidelity of translation in this pea system is at least as high as in a wheat embryo cell-free protein synthesizing system. The endogenous messengers are also efficiently translated in extracts from the primary axes of pea seeds. The direct translation of these messengers in a homologous cell-free system may be of interest for a study of the products coded for by the long-lived messengers present in this plant.
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  • 19
    ISSN: 1432-2048
    Keywords: Amino acids (in chloroplasts) ; Chlorplast preparation ; Pisum ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A procedure is described for the rapid (〈5 min) isolation of purified, physiologically active chloroplasts from Pisum sativum L. Mitochondrial and microbody contamination is substantially reduced and broken chloroplasts are excluded by washing through a layer containing a treated silica sol. On average the preparations contain 93% intact chloroplasts and show high rates of 14CO2 fixation and CO2-dependent O2 evolution (over 100 μmol/mg chlorophyll(chl)/h); they are also able to carry out light-driven incorporation of leucine into protein (4 nmol/mg chl/h). The amino-acid contents of chloroplasts prepared from leaves and from leaf protoplasts have been determined. Asparagine is the most abundant amino acid in the pea chloroplast (〉240 nmol/mg chl), even thought it is proportionately lower in the chloroplast relative to the rest of the cell. The chloroplasts contain about 20% of many of the amino acids of the cell, but for individual amino acids the percentage in the chloroplast ranges from 8 to 40% of the cell total. Glutamic acid, glutamine and aspartic acid are enriched in the chloroplasts, while asparagine, homoserine and β-(isoxazolin-5-one-2-yl)-alanine are relatively lower. Leakage of amino acids from the chloroplast during preparation or repeated washing was ca. 20%. Some differences exist between the amino-acid composition of chloroplasts isolated from intact leaves and from protoplasts. In particular, γ-aminobutyric acid accumulates to high levels, while homoserine and glutamic acid decrease, during protoplast formation and breakage.
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  • 20
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    Planta 148 (1980), S. 437-443 
    ISSN: 1432-2048
    Keywords: Chloroplasts (number, DNA) ; DNA (chloroplast) ; Pisum ; Protoplasts
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Protoplasts were prepared from pea (Pisum sativum L.) leaves throughout development and their contents spread in a monolayer to determine the number of chloroplasts per cell. This approach permitted the rapid analysis of more than 100 cells at each stage of development. The average number of chloroplasts per cell increased from 24±10 to 64±20 during greening and expansion of the first true foliage leaves; all cells containing chloroplasts apparently increase their chloroplast number. A parallel increase in the amount of DNA per nucleus was not observed. As the leaves senesced the chloroplast number gradually decreased to 44±12. We have correlated these changes with our previous results on the percentage of chloroplast DNA per cell. Chloroplast multiplication resulted in a 2.7-fold dilution (from 272 to 102) of the number of copies of the chloroplast DNA molecule per plastid.
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  • 21
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; choice of oviposition site ; strain difference ; site discrimination ; egg insertion ; selection ; wild type
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Females ofDrosophila melanogaster were given a choice of oviposition site either on the surface of the medium or on the surface of paper positioned vertically on the medium. A significant difference was seen in the proportion of eggs deposited on the paper among wild strains of different geographic origins. Bidirectional selection for oviposition on these two sites was effective. These selected lines were examined under various conditions to determine the factors involved in this site selection for oviposition. The lines that chose medium laid eggs only on substrates into which egges could be inserted. The lines preferring paper showed no strict requirement for burying their eggs. Tarsal sensillae were involved in site discrimination.
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  • 22
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    Behavior genetics 10 (1980), S. 163-170 
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; mating success ; male fertility ; male age ; female choice experiments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Female choice experiments were used to investigate the effect of relative male age on mating success inD. melanogaster. Experiments were conducted with a Canton-S (CS) strain, in which two virgin males of different ages (2, 4, or 8 days old) were offered to virgin females. Older males were found to be more successful under competitive conditions. In another group of experiments, vermilion (v) males of different ages competed with CS males of different ages. The competitive success ofv males was found to increase with their relative age. Male fertility at 2, 4, and 8 days of age was documented for both male genotypes mated with CS females. CS males fathered more offspring per copulation thanv males, and the fertility of all males was found to increase with age. Discussion focuses on the changes in male mating success and fertility with age and genotype.
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  • 23
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    Biochemical genetics 18 (1980), S. 65-76 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; cuticle ; chitin ; β-alanine ; N-acetyldopamine ; tanning ; melanization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract In Drosophila melanogaster, the chitinous microfibrils arising from the tips of the epidermal villi in adult cuticles remain irregular and loose in the mutant ebony (which fails in cuticular incorporation of β-alanine) but closely knit and regular in normal flies. Addition of β-alanine to cuticles from which nonchitinous materials have been removed with alkali converts the loose arrangement of the microfibrils to a compact and sharply delineated arrangement. β-alanine also accelerates tyrosinase-catalyzed oxidation of N-acetyldopamine by reacting with the oxidized product of the reaction to produce an orange-red complex. Similarly, β-alanine accelerates oxidation of N-acetyldopamine when these two substances are added to fluids from the hemocoel, to lead to tanning instead of normal blackening. These findings may help explain why β-alanine induces tanning while inhibiting melanization in insects.
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  • 24
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; 6-phosphogluconate dehydrogenase ; isozyme
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract 6-Phosphogluconate dehyrogenase is evident at all developmental stages of Drosophila melanogaster. The activity level is highest in early third instar larvae and declines to a lower, but relatively constant, level at all later stages of development. The enzyme is localized in the cytosolic portion of the cell. The A-isozymic form of 6-phosphogluconate dehydrogenase was purified to homogeneity and has a molecular weight of 105,000. The enzyme is a dimer consisting of subunits with molecular weights of 55,000 and 53,000. For the oxidative decarboxylation of 6-phosphogluconate the Km for substrate is 81 µm while that for NADP+ is 22.3 µm. The optimum pH for activity is 7.8 while the optimum temperature is 37 C.
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  • 25
    ISSN: 1573-4927
    Keywords: Tryptophan ; kynurenine ; white ; Drosophila melanogaster ; amino acid transport ; Malpighian tubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Dissected Malpighian tubules from wild type and the eye color mutant white of Drosophila were compared with respect to their abilities to transport tryptophan and kynurenine into tubule cells. It was determined that mutation at white greatly impairs the ability of Malpighian tubule cells to take up tryptophan. Functional studies on the extracellular spaces and ultrastructural observations indicated no differences in these respects between wild type and white tubules. It is consistent with several observations that much of the tryptophan associated with white exists in the intercellular spaces. Furthermore, the uptake of tryptophan by the w + system of wild type tubules is inhibited by the analogue 5-methyl-tryptophan. However, the incorporation of radioactive tryptophan into protein in tubule cells from wild type and white occurs at the same rates and is not affected by 5-methyl-tryptophan. Therefore, it is apparent that Malpighian tubules have a transport system that enables entry of tryptophan into a cellular pool and that this cellular pool is initially independent of the tryptophan pool used for protein synthesis. The mutant white lacks this transport system. From these studies and others it appears that compartmentalization of cellular pools may be brought about via the utilization of specific membrane transport systems.
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    Biochemical genetics 18 (1980), S. 303-309 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; allozymes ; GPT ; genetic mapping
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    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract We have used electrophoretic variants of glutamate-pyruvate transaminase (GPT, E.C. 2.6.1.2) in Drosophila melanogaster to genetically map the structural gene to position 42.6 on the X chromosome. By pseudodominance tests over several deficiencies we have localized it cytogenetically to the interval 11Fl-2 to 12Al-2. The sedimentation constant (s 20,w) of the native enzyme was determined in sucrose density gradients to be 5.9 and the native molecular weight approximately 87,000. The similarity in physical properties to mammalian enzymes suggests that the enzyme may also be dimeric in D. melanogaster.
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  • 27
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    Biochemical genetics 18 (1980), S. 699-715 
    ISSN: 1573-4927
    Keywords: modifying genes ; G6PD activity ; 6PGD activity ; Drosophila melanogaster ; enzyme polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Different homozygous lines of similar genotype with respect to G6pd and 6Pgd were shown to have different enzyme activities for G6PD and 6PGD. Crosses between high and low lines suggested that there were modifying genes present on the autosomes, while others were probably located on the X chromosome. Allelic variation within each electrophoretic class of G6pd and 6Pgd might, however, also have contributed to this variation. An experiment on adaptation to sodium octanoate demonstrated that in adapted flies selection for lower enzyme activity had occurred, which provided further evidence for the existence of genetic differences in activity. Furthermore, a strong positive correlation between the activities of G6PD and 6PGD was found for each genotype. Since no correlation was found between MDH and the two enzymes G6PD and 6PGD, it could be concluded that this correlation was probably rather specific for G6PD and 6PGD. Interaction between genotypes with respect to activity was also found. It was shown that the variation at 6Pgd influenced the activity of G6PD within a genotype. The data are discussed in relation to fitness differences presented in foregoing articles.
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    Biochemical genetics 18 (1980), S. 905-913 
    ISSN: 1573-4927
    Keywords: Drosophila melanogaster ; allozymes ; α-glycerophosphate dehydrogenase ; frequency-dependent selection
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Polymorphism at the α-Gpdh locus was studied in Drosophila melanogaster. Using two different lines, one marked by the F allele (FF line) another by the S allele (SS line), four populations were initiated, two in which the initial frequency of F was 0.1 and two in which it was 0.9. They have been observed for 34 generations. From the fifth generation on, the equilibrium frequency in the four cages was about 0.60. Viability has been measured during the evolution of the populations while F frequencies changed and recombinations between the FF and SS lines occurred. It has also been evaluated in synthetic populations built with different frequencies: (1) from the original FF and SS lines and (2) from FF and SS lines extracted after 34 generations of joint evolution. In all three cases, the FF viability depended on the frequency of the F allele. The similarity of the three linear regressions implies that the α-Gpdh locus or other closely linked loci is the target of the selection in the populations analyzed here.
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    Behavior genetics 10 (1980), S. 183-190 
    ISSN: 1573-3297
    Keywords: ethanol ; Drosophila melanogaster ; larvae ; strain difference ; habitat selection ; isofemale strains
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract There is a latitudinal cline in attraction to ethanol of newly hatchedD. melanogaster larvae; attraction decreases as one moves from the temperate regions to the Australian tropics. Tropical populations manifest high levels of heterogeneity compared with temperate regions, making tropical populations less dependent on ethanol. Since ethanol is a resource forD. melanogaster, an approach to the genetics of resource utilization in natural populations via behavior genetics of larval ethanol responses is feasible, using isofemale strains as experimental material.
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  • 30
    ISSN: 1573-3297
    Keywords: Drosophila melanogaster ; Drosophila simulans ; hybrid behavior ; transition analysis ; courtship sequences
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    Topics: Biology , Psychology
    Notes: Abstract Several transitions between sequential male courtship elements were analyzed forDrosophila melanogaster its close relativeD. simulans, and two types of hybrid males. Hybrid males from special reciprocal crosses did not differ. WhileD. melanogaster andD. simulans males differed markedly for the majority of transitions studied, hybrid males showed no consistent pattern with the parent species, being indistinguishable fromD. simulans males, indistinguishable fromD. melanogaster, or intermediate between them, depending on the trait observed. This suggests independent genetic control of these transitions during male courtship.
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    Planta 150 (1980), S. 82-88 
    ISSN: 1432-2048
    Keywords: Legumin ; Pisum ; Protein (storage) ; Storage protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Since there is some question as to whether or not legumin is glycosylated, this storage protein was isolated by various procedures from developing cotyledons of Pisum sativum L. supplied with [14C]-labeled glucosamine and analyzed by sodium dodecylsulfate-polyacrylamide gel electrophoresis. Legumin isolated by the classical method of Danielsson [(1949) Biochem. J. 44, 387–400] a procedure in which globulins extracted with a buffered salt solution are precipitated with ammonium sulfate (70% saturation) and legumin separated from vicilin by isoelectric precipitation, was labeled. The glucosamine incorporated into legumin was associated with low-molecular-weight polypeptides. In contrast, legumin isolated by the method of Casey [(1979) Biochem. J. 177, 509–520], a procedure where legumin is prepared by zonal isoelectric precipitation from globulins precipitated with 40–70% ammonium sulfate, was not labeled. However, the globulin fraction precipitated with 40% ammonium sulfate was labeled and the radioactive glucosamine was associated with low-molecular-weight polypeptides. Legumin isolated from protein bodies [Thomson et al. (1978) Aust. J. Plant Physiol. 5, 263–279] was not extensively labeled. However, the saltinsoluble fraction of protein body extracts was labeled and the radioactivity was associated with low-molecular-weight polypeptides. These results indicate that protein bodies contain a glycoprotein of low-molecular-weight that co-purifies with legumin isolated by the method of Danielsson but that is discarded when isolation methods developed more recently are used.
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  • 32
    ISSN: 1432-2048
    Keywords: Auxin ; Cell elongation ; Epidermis peeling ; Fusicoccin ; Pisum
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    Topics: Biology
    Notes: Abstract The effects of peeling and wounding on the indole-3-acetic acid (IAA) and fusicoccin (FC) growth response of etiolated Pisum sativum L. cv. Alaska stem tissue were examined. Over a 5 h growth period, peeling was found to virtually eliminate the IAA response, but about 30% of the FC response remained. In contrast, unpeeled segments wounded with six vertical slits exhibited significant responses to both IAA and FC, indicating that peeling does not act by damaging the tissue. Microscopy showed that the epidermis was removed intact and that the underlying tissue was essentially undamaged. Neither the addition of 2% sucrose to the incubation medium nor the use of a range of IAA concentrations down to 10-8 M restored IAA-induced growth in peeled segments, suggesting that lack of osmotic solutes and supra-optimal uptake of IAA were not important factors over this time period. It is concluded that, although the possibility remains that peeling merely allows leakage of hydrogen ions into the medium, it seems more likely that peeling off the epidermis removes the auxin responsive tissue.
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    Theoretical and applied genetics 56 (1980), S. 161-173 
    ISSN: 1432-2242
    Keywords: Drosophila melanogaster ; Chromosome ; Spontaneous interchange ; half-translocation ; Non-homologous pairing ; Mitosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Herein is described an attempts to establish chromosome pairing-interchange relationships in Drosophila melanogaster female. For this purpose, the formation of half-translocations was studied in XXY and XX females bearing compounds of the second pair of autosomes. With respect to XXY females, it was expected that the free Y chromosome would pair with these compounds and that half-translocations involving 2L would arise. In as much as compound chromosomes in XX females had no partner for pairing, the formation of half-translocations involving 2L was not expected. Half-translocations were registered in the F1 from crosses of XX and XXY females to b j pr cn/T(Y;2)C males. The cross was designed to permit the detection of very rarely occurring non-homologue interchanges. Offspring number was 335 in XX females and 550 in XXY females. The majority of offspring consisted of individuals arisen from the spontaneous restitution of compounds and the formation of 2n egg cells. Based on phenotype, the offspring of XX females contained 4 individuals with half-translocations involving 2L; there were 48 such flies among the offspring of XXY females. As confirmed by progeny analysis, 38 half-translocations occurred in XXY females and none in XX females. Of the 31 spontaneous interchanges in XXY females 28 were recorded between the Y and the left compound, one between the Y and the right compound, and one between the X and the left compound. Non-homologue interchanges were of oogonial origin judging by the fact that individuals with half-translocations arose in clusters. Unlike Y — left compound interchanges, the interchanges between autosomal compounds seem to be of meiotic origin.
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    Theoretical and applied genetics 57 (1980), S. 25-32 
    ISSN: 1432-2242
    Keywords: Long-term selection ; Residual genetic variability ; Heritability ; Abdominal bristle number ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Six replicate lines of Drosophila melanogaster, which had been selected for increased abdominal bristle number for more than 85 generations, were assayed by hierarchical analysis of variance and offspring on parent regression immediately after selection ceased, and by single-generation realised heritability after more than 25 generations of subsequent relaxed selection. Half-sib estimates of heritability in 5 lines were as high as in the base population and much higher than observed genetic gains would suggest, excluding lack of sufficient additive genetic variance as a cause of ineffective selection in these lines. Also, there was considerable diversity among the six lines in composition of phenotypic variability: in addition to differences in the additive genetic component, one or more of the components due to dominance, epistasis, sex-linkage or genotype-environment interaction appeared to be important in different lines. Even after relaxed selection, single-generation realised heritabilities in four lines were as high as in the base population. As a large proportion of total genetic gain must have been made by fixation of favourable alleles, the compensatory increase of genetic variability has been sought in a genetic model involving genes at low initial frequencies, enhancement of gene effects during selection and/or new mutations.
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    Theoretical and applied genetics 57 (1980), S. 113-117 
    ISSN: 1432-2242
    Keywords: Long-term selection ; Relaxed selection ; Reverse selection ; Dominance of bristle number genes ; Drosophila melanogaster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Reverse and relaxed selection were carried out in sublines which were derived from six replicate lines of Drosophila during 86–89 generations of selection for increased abdominal bristle number, and the reverse selection sublines were reciprocally crossed with selection lines of their origin. The results of serial relaxed selection initiated at different generations of selection confirm that the accelerated responses observed in the selection lines were largely due to deleterious genes, particularly lethals, with large effects on the selected character. The decline in mean bristle number under relaxed selection was not much different between crowded and uncrowded relaxed sublines. Reverse selection initiated at generation 57 was very effective, though it failed to bring the mean back to the base population level, and the genetic differences between replicate sublines (two from each of the six lines) indicate that low bristle number genes were probably rare in the selection lines. The genes which were still segregating after 57 generations of selection, on the average, did not show any directional dominance. The contribution of the X-chromosome to selection response was proportional to its chromosome length.
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    Theoretical and applied genetics 57 (1980), S. 247-255 
    ISSN: 1432-2242
    Keywords: Compound ; free-arm strains ; Drosophila melanogaster ; Unstable genetic isolation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Crosses between compound-2L; free-2R (free-arm) and standard strains of Drosophila melanogaster produce two classes of inviable aneuploid hybrids in equal proportions: monosomic 2L and trisomic 2L. The lethal period for monosomics occurs during embryogenesis while the trisomics survive to late pupae. Since the hybrids are inviable, standard and free-arm strains within a mixed population remain genetically isolated. Genetic isolation in the absence of mating isolation offers an extreme example of unstable equilibrium. Relative fitness data indicate that an unstable equilibrium will be established between free-arm and standard strains at a ratio of 2.5∶1. Indeed, in three cage experiments established at initial ratios of 3∶1, free arms to standards, laboratory (Oregon R) or native (Okanagan S) standard strains were completely replaced in approximately 100 days by free-arm lines derived either from laboratory or from native genetic background. In contrast, one cage established at an initial ratio of 4∶1 failed to show replacement and for 92 days remained at approximately the initial ratio. Subsequent genetic analysis of flies removed from this cage identified the presence of an anomalous strain through which genetic information was transferred reciprocally between the free-arm and standard lines. The second chromosomes carried by this strain consisted of a free-2R and a standard second on the right arm of which was attached a duplication for all of 2L. While the origin of the 2L·2R+2L chromosome was uncertain, genetic and cytological examinations revealed that it represented the reciprocal crossover product expected from an exchange that generated a F(2R). Additional crosses disclosed that the transmission frequency of the asymmetrical pair of second chromosomes, as well as their right-arm crossover products, was disproportionately in favor of the short arm. Since unequal transmission was invariably greater from female parents, this phenomenon was viewed as further evidence in support of the drag hypothesis.
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  • 37
    ISSN: 1573-3297
    Keywords: mating success ; allozyme polymorphism ; overdominance ; mating latency ; Adh locus ; Drosophila melanogaster ; rare genotype mating advantage ; alcohol dehydrogenase ; statistical methods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Strains ofDrosophila melanogaster having different alcohol dehydrogenase (Adh) genotypes (FF, FS, or SS) were assembled in a mating chamber in varying ratios, and the mating successes were recorded. In experiments with a 25∶25 ratio, theFF males succeeded in mating more than didFS andSS males, while theFS males surpassed theSS males. As for the females,FF also surpassedSS. In experiments with a 5∶45 or 45∶5 ratio, some differences from the 25∶25 ratio occurred, but in these cases the rare genotypes were at a disadvantage. In one case, female genotypes (FF vs.SS) displayed a difference in mating latency time, but male genotypes did not. The findings did not suggest that rare genotype mating advantage and overdominance in mating success play a role in the maintenance of theAdh polymorphism.
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    Behavior genetics 10 (1980), S. 291-302 
    ISSN: 1573-3297
    Keywords: foraging strategies ; chromosomal analysis ; Drosophila melanogaster ; larvae ; feeding-locomotor behavior
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract Two larval foraging strategies inDrosophila melanogaster were identified, “rover” and “sitter.” “Rovers” traverse a large area while feeding whereas “sitters” cover a small area. The difference between “rovers” and “sitters” was analyzed genetically by chromosomal substitutions between isogenic stocks. Differences in larval locomotor behavior (“crawling behavior”) can be attributed to the second chromosome, the “rover” strategy being dominant over the “sitter” strategy. Differences in feeding rate (“shoveling behavior”) are affected additively by both the second and third chromosomes. Natural populations ofDrosophila larvae were sampled three times over a 2-month period; “rovers” and “sitters” were at constant frequencies in these populations. The two foraging strategies are discussed in the light of resource utilization in environments where food is distributed continuously or discontinuously.
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    Plant and soil 56 (1980), S. 335-340 
    ISSN: 1573-5036
    Keywords: Acetylene reduction ; Field method ; Nitrogen fixation ; Non-destructive ; Pisum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Direct injection of acetylene into soil around plant roots, followed by determination of ethylene/acetylene ratios in the soil atmosphere has been tested as a rapid, non-destructive method of estimating acetylene reducing activity. In pots of artificial media as well as in field soil, the ratios determined within 10 min. after injection were significantly correlated with the rates of acetylenedependent ethylene production in detached roots. The method may be useful in preliminary screening of large numbers of plant-bacteria combinations.
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