ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Articles  (5)
  • wheat
  • Springer  (5)
  • American Chemical Society
  • American Institute of Physics (AIP)
  • Hindawi
  • 2010-2014
  • 1995-1999  (5)
  • Chemistry and Pharmacology  (5)
Collection
  • Articles  (5)
Publisher
  • Springer  (5)
  • American Chemical Society
  • American Institute of Physics (AIP)
  • Hindawi
Years
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 23 (1997), S. 2695-2705 
    ISSN: 1573-1561
    Keywords: Defense ; herbivory ; aphids ; wheat ; Gramineae ; hydroxamic acids ; Defense theory ; Carbon/Nutrient theory
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Hydroxamic acids (Hx) are natural products of Gramineae that are associated with cereal resistance to pests. We aimed at characterizing the induction of Hx accumulation in seedlings of wheat,Triticum aestivum, by short-term infestation of the cereal aphid,Rhopalosiphum padi. A load of 25 aphids increased significantly the Hx levels in the infested primary leaf in comparison with control levels. Lower loads did not increase Hx concentration. Aphid infestation lasting 16 hr did not elicit induction of Hx, even after a time-lag of 32 hr to allow the expression of any induced response. Forty-eight hours was the minimum duration of aphid infestation required to trigger Hx induction. The age of the infested tissue (the primary leaf) did not affect induction. Similar increases of Hx were found in unfolding, expanding, and totally expanded primary leaves. It was determined that the regime of nutrient supply (N-intensive nutritive solutions at low and high concentration) to wheat seedlings had no effect on the magnitude of the aphid-induced Hx (N-based secondary metabolites). Results obtained are discussed in the framework of general theories of plant defense allocation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-1561
    Keywords: α-Amylase inhibitors ; trypsin inhibitors ; cereal endosperm ; wheat ; barley ; Spodoptera frugiperda ; digestive enzymes ; midgut proteases
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The α-amylase activity was determined throughout the larval development of Spodoptera frugiperda. Maximal activities with optimal pH in the range 8.5–9.5 were found in last instars. Protein preparations enriched in heterotetrameric inhibitors from wheat flour were active towards gut amylases from last instars, while those corresponding to homodimeric and monomeric inhibitors showed low inhibition levels. These results were further supported by testing purified members of each inhibitor type and by analyzing the effects of the inhibitors on the amylase isoenzyme pattern from native PAGE. High levels of trypsin-like activity were also found in gut extracts from last instars. Different genetic variants of the major barley trypsin inhibitor were active against this gut enzyme. None of the other larval digestive protease activities (chymotrypsin-like, elastase-like, leucine aminopeptidase-like, and carboxypeptidase A and B-like) were inhibited, indicating that the barley inhibitor is specific towards trypsin-like enzymes.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-1561
    Keywords: Spacing pheromones ; olfactometry ; aphids ; wheat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Olfactometry using an apterous individual of Rhopalosiphum padi (L.) showed an arresting effect by volatiles from a wheat seedling and a repellent effect by volatiles from a wheat seedling infested with aphids at a high population density (ca. 9 aphids/cm2). Four compounds, 6-methyl-5-hepten-2-one, (−)- and (+)-6-methyl-5-hepten-2-ol, and 2-tridecanone, were identified by GC-MS in air entrainments from the wheat seedlings with high aphid density but not from the wheat seedlings alone. The mixture of the four compounds in the natural proportion counteracted the attractivity of the volatiles from the intact uninfested wheat seedling. The likely role of these compounds in the spacing behavior of this aphid species, when present in high densities on wheat, is discussed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Journal of chemical ecology 23 (1997), S. 543-551 
    ISSN: 1573-1561
    Keywords: Temperature ; photoperiod ; hydroxamic acids ; growth ; defense ; secondary metabolites ; wheat ; Gramineae
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract The effects of temperature and photoperiod on accumulation of hydroxamic acids (Hx) in wheat (Triticum aestivum L.) seedlings were evaluated under laboratory conditions. Hx concentrations were significantly higher at higher temperatures. No such clear trend was found for the photoperiod effect. The significant effect of temperature and photoperiod on growth rate of seedlings and the significant positive correlation between growth rate prior to analysis and levels of Hx, suggested that environmental effects on Hx accumulation were at least partially mediated through their effect on plant growth rate. After uncoupling the effect of environmental conditions from the effect of plant growth rate by statistical means the effect of temperature on Hx was no longer significant. Therefore, temperature effect was fully mediated by plant growth rate. Implications of the patterns found are discussed in issues of plant-defense general theories.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1573-1561
    Keywords: Kairomone ; biological control ; cabbage ; wheat ; Diuraphis noxia ; Brevicoryne brassicae ; olfactometer ; infochemical ; preference ; host plants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Diaeretiella rapae (M'Intosh) (Hymenoptera: Aphidiidae) is a parasitoid of several aphid species, including the Russian wheat aphid (RWA),Diuraphis noxia (Mordvilko), and the cabbage aphid (CA).Brevicoryne brassicae (L.). The response of matedD. rapae females to odors from wheat, cabbage, and plant-host complexes was investigated using a four-choice olfactometer. Experienced parasitoids, but not inexperienced females, responded positively to odors of the wheat-RWA complex in a no-choice test. In choice tests, experienced parasitoids did not respond to odors of uninfested cabbage and wheat leaves, but did respond positively to aphid-infested plants and to aphids alone. The response ofD. rapae to the cabbage-CA complex and to CA alone was significantly greater than to the wheat-RWA complex and RWA alone, suggesting an innate odor preference for crucifer-feeding aphids.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...