GLORIA

GEOMAR Library Ocean Research Information Access

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Hyperparasitoid defense strategies against spiders: the role of chemical and morphological protection (2000)
    Springer
    Entomologia experimentalis et applicata 97 (2000), S. 67-74 
    Details
    ISSN: 1570-7458
    Keywords: aphid hyperparasitoid ; Alloxysta ; predation ; spiders ; chemical defense ; morphological resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The aphid endohyperparasitoid Alloxysta brevis(Thomson) (Hymenoptera: Charipidae) applies defensive chemicals stored in mandibular gland reservoirs against attacking ants. Alloxystines can be divided into species capable of exploiting ant-attended resources and into species exclusively reared from unattended aphid-parasitoid systems. Mandibular secretions are found in species of both groups, with little variation in chemical composition. We show that the mandibular gland secretion does not only protect against ant attacks but acts as an overall defense agent against generalist predators like spiders. The protective success differed with the spider species. The web-building spider Agelena labyrinthica(Clerck) (Araneae: Agelinidae) killed 57% of attacked A. brevisfemales, but sucked out only 8%. The smaller free-hunting jumping spider Salticus scenicus(Clerck) (Araneae: Salticidae) failed in overwhelming or severely injuring A. brevis. The pattern of interactions showed striking similarities with interactions between A. brevisand the ant Lasius niger(Hymenoptera: Formicidae). Primary parasitoids which are lacking chemical defense and sufficient morphological protection suffered significantly higher mortality due to spider predation. Our results indicate that – additional to chemical defense- parasitoid survival depends on the specific morphological resistance against grip pressure during capture, and on the predator – prey size relationship.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1004069524135
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Differential Interactions Between an Aphid Endohyperparasitoid and Three Honeydew-Collecting Ant Species: A Field Study of Alloxysta brevis (Thomson) (Hymenoptera: Alloxystidae) (2000)
    Springer
    Journal of insect behavior 13 (2000), S. 771-784 
    Details
    ISSN: 1572-8889
    Keywords: Alloxysta brevis ; aphid hyperparasitoid ; ant aggression ; interaction patterns ; chemical defense ; escape behavior ; hyperparasitoid sex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The behavioral interactions between the chemically protected aphid hyperparasitoid Alloxysta brevis and three trophobiotic ant species were examined in the field on thistles. The patterns were not essentially influenced by hyperparasitoid sex. Ants differed in their guarding behavior of aphids and their response toward A. brevis. Lasius niger attacked the hyperparasitoid more readily than Myrmica laevinodis, while aggression by Formica rufa was intermediate. Apart from applying chemical defense, A. brevis responded to ants by flying away (mainly at L. niger) or with avoidance behavior (mainly at M. laevinodis). Additionally, females might switch their tactics from flight to defense with increasing age. Females left the plant more often after encounters with L. niger or F. rufa than with M. laevinodis. Disturbance by any ant species affected the foraging activities, reducing oviposition success to nearly zero.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1007856330094
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Zur Wasserpermeabilität der Internodialzellen von Tolypella nidifica (1965)
    Springer
    Naturwissenschaften 52 (1965), S. 619-619 
    Details
    ISSN: 1432-1904
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00622135
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Die WasserpermeabilitÄt pflanzlicher Zellen (1965)
    Springer
    Protoplasma 60 (1965), S. 401-425 
    Details
    ISSN: 1615-6102
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Zusammenfassung 1. Der Austausch des Gewebewassers von Wurzeln gegen Wasser des umgebenden Mediums erfolgt mit der gleichen Geschwindigkeit, mit der Wasser durch hypertonische Lösungen den Wurzeln entzogen wird. 2. In hypertonischen Lösungen wird die Geschwindigkeit des H2O/HDO-Austausches nicht verÄndert. 3. Mit hypertonischen Saccharoselösungen vorbehandelte Wurzeln lassen einen zunÄchst sehr raschen, danach langsamer ablaufenden Wasseraustausch erkennen. Der rasche Proze\ (t 1/2=9 sec) entspricht nahezu der freien Diffusion des Wassers, der langsame Proze\ (t 1/2=150 sec) gibt die Wasserpermeation durch die plasmolysierten Protoplasten wieder. 4. Internodialzellen vonTolypella nidifica zeigen unter bestimmten Bedingungen Abweichungen von der Osmometertheorie. Einseitig oder beidseitig offene Internodialzellen sind plasmolysierbar. 5. Die Grö\enD.q/R.T.l der Diffusionsgleichung undr 2. q/8η. l der Strömungsgleichung stellen Grenzwerte der WasserpermeabilitÄtskonstanteP w in der allgemeinen PermeabilitÄtsgleichung dm/dt=Pw (p 1 −p 2) dar.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01247889
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Proton relaxation in aqueous DNA solutions (1969)
    New York : Wiley-Blackwell
    Biopolymers 7 (1969), S. 447-452 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: By use of D2O we found that the shortening of the longitudinal proton relaxation time which occurs in the investigated aqueous yeast DNA solutions (≦ 2.4% with 2% protein) was not based on a hydration effect, but was caused by magnetic impurities only. An estimate shows that the mobility of the hydrated water molecules is reduced by less than two orders of magnitude in comparison with the free water molecules.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1969.360070403
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Zur Theorie der α-Ketosäuren, XIII. Struktur und Stabilität von Protonen- und Metallchelaten in wäßrigem Medium (1965)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 98 (1965), S. 3578-3581 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Halogenierungsgeschwindigkeit o-hydroxy- und o-carboxy-substituierter Acetophenonderivate wird durch Mineralsäuren nicht beeinflußt, da die in wäßriger Lösung gebildeten Protonenchelate das Molekül vor dem Einfluß von Fremdsäuren schützen. Die für α-Ketosäuren typische Metallionen-Katalyse der Halogenierung wird bei den untersuchten Derivaten des Acetophenons nicht beobachtet.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19650981121
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Untersuchungen zur Theorie der α-Ketosäuren, XII: Säure- und basenkatalysierte Keto-Enol-Umlagerung bei α-Ketosäuren in Wasser (1965)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 98 (1965), S. 1938-1948 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die Geschwindigkeiten der säure- und basenkatalysierten Keto-Enol-Umlagerung von Aceton, Methyläthylketon, Brenztraubensäure, Methylbrenztrauben-säure, Dimethylbrenztraubensäure und Lävulinsäure in wäßr. Lösung wurden durch kolorimetrische Messung der Anfangsgeschwindigkeit der Jodanlagerung bestimmt. Es zeigt sich, daß α-Ketosäuren auch in wäßrigem Medium als Protonenchelate vorliegen, wobei die Wasserstoff-Brücke durch intramolekulare Säurekatalyse die Umwandlungsgeschwindigkeit der Säuren erhöht und das Molekül gleichzeitig vor dem Angriff von Fremdsäuren schützt. Komplexaktive Metall-lonen (Zn) beschleunigen die Umwandlungsgeschwindigkeit der α-Ketosäuren erheblich.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19650980632
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...