Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Homoptera  (2)
  • pasture  (2)
  • Analytical Chemistry and Spectroscopy  (1)
  • 1
    ISSN: 1572-9680
    Keywords: borescope ; competition ; herbicide ; minirhizotron ; pasture ; Prunus avium ; silvopastoral
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract The use of a simple counting method using a borescope and minirhizotron system to study the interaction of roots of wild cherry trees (Prunus avium L) and pasture in an upland silvopastoral system is described. Operator variation was greatest when distinguishing different tree root categories (e.g. white, brown, woody) but was not significant in relation to total tree or grass root counts or species differences. Analysis of covariance was used to take these differences into account in a field trial using several operators. The seasonal patterns of tree and pasture root growth were different. Tree roots peaked in May before maximal shoot growth. The peak in pasture roots occurred two weeks earlier. Tree height growth was increased by the use of herbicides to control grass growth but this effect was only apparent during August when the soil was dry and when pasture root counts were reduced.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-1561
    Keywords: Damson-hop aphid ; Phorodon humuli ; Homoptera ; Aphididae ; methyl salicylate ; (E)-2-hexenal ; β-caryophyllene ; semiochemicals ; aggregation ; attractant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Behavioral studies using an olfactometer demonstrated that spring migrants of the damson-hop aphid,Phorodon humuli, respond to semiochemicals released by spring migrants feeding on hop leaves. Samples of the total volatiles released on feeding were analyzed by coupled gas chromatographysingle cell recording techniques and showed the presence of several active components. Three compounds were identified, using coupled gas chromatography-mass spectrometry, as methyl salicylate, (E)-2-hexenal andβ-caryophyllene. These three compounds elicited responses from separate olfactory receptors on the antenna. In the olfactometer, both (E)-2-hexenal andβ-caryophyllene gave positive responses from spring migrants, and a mixture of the two compounds in the natural ratio was more attractive than (E)-2-hexenal alone. Addition of methyl salicylate eliminated the response to the active binary mixture.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-1561
    Keywords: Pheromone ; sex ; attractant ; aphid ; Phorodon humuli ; Homoptera ; Aphididae ; nepetalactol ; monoterpenoid ; electrophysiology ; single cell recording ; mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Behavioral studies using an olfactometer demonstrated that sexual females (oviparae) of the damson-hop aphid,Phorodon humuli, release a pheromone to which males respond. Volatiles produced by the oviparae were analyzed by coupled gas chromatography-single cell recording from the secondary rhinaria on the male antenna and showed the presence of one peak with major activity. Coupled gas chrornatography-mass spectrometry suggested a nepetalactol, which was shown to have the 4aR, 7S, 7aS stereochemistry by synthesis from the corresponding nepetalactone isolated from the labiate plantNepeta mussinii. Although the stereochemistry at carbon-1 is not yet established, a synthetic sample comprising ca. 70% 1S and 30% 1R attracted highly significant numbers of males to water traps placed within and adjacent to a hop garden. Initial studies also indicated attraction of males in both the olfactometer and in the field by volatiles from the primary host.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1573-5036
    Keywords: borescope ; minirhizotron ; pasture ; root length density ; silvopastoral ; wild cherry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract A method for counting root intersections with observation tubes (mini- or micro-rhizotrons) is proposed that allows a theoretical conversion of root counts to estimated root length density and which is robust to the effects of tracking along the tubes. A field test showed that the method agreed well with measured root length densities in cores for wild cherry roots but not for roots of pasture species. The circumstances in which the method might be expected to perform well are discussed. Analysis of data from a field trial revealed that root counts were not uniformly distributed around the circumference of the observation tube. Implications for the design of such trials are noted.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Journal of Raman Spectroscopy 22 (1991), S. 771-775 
    ISSN: 0377-0486
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Surface-enhanced Raman scattering (SERS) from citrate-coated colloidal particles suspended in organic solvents is used to study surface reactions in an organic phase. Stable colloids which gave good SERS were produced from ethanol and acetonitrile. SERS was easily discriminated from the bulk solvent Raman scattering. Compounds which are sparingly soluble in water including 2,2′-bipyridine and benzene-1,2,4,5-tetracarboxylic acid dianhydride produced good SERS in ethanol. In the latter case, no SERS was observed from an aqueous colloid. Therefore, some form of solvent-dependent molecular recognition may operate. The formation of a bipyridine complex with copper(II) at the surface in a solvent system in which the ligand and complex are both soluble was observed. The solvent altered surface reactions. In the ethanol colloid, in contrast to the result in aqueous colloid, pyridine does not replace citrate readily. This work demonstrates the potential for the expansion of the use of colloidal SERS into the field of surface reactions in contact with an organic phase and is related to metal liquid-like films.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...