• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Preferencia de Gonipterus scutellatus Gyllenhal (Coleoptera: curculionidae) por hojas de distintas especies de eucaliptol

García Safe, Diego Raúl January 2008 (has links)
Memoria para optar al Título Profesional de Ingeniero Forestal / En 1998 aparece en Chile el gorgojo del eucalipto (Gonipterus scutellatus Gyllenhal (Col.: Curculionidae), insecto de origen australiano, y con ello una preocupación creciente por las más de 525.000 ha plantadas con especies de Eucalipto. Esta plaga se ha expandido por las regiones IV a IX, causando pérdida de crecimiento, deformaciones de fuste e incluso la muerte de plantas afectadas, como consecuencia de las defoliaciones. Este estudio abordó, por una parte, la preferencia de adultos de este insecto entre tres especies de eucalipto: E. globulus, E. nitens y E. camaldulensis, y por otra, la composición de los aceites esenciales en las especies estudiadas, que podrían incidir en la resistencia a la infestación de este curculiónido.
2

Identification of volatile organic compounds from Eucalyptus detected by Gonipterus scutellatus (Gyllenhal) females

Bouwer, Marc Clement 11 November 2010 (has links)
This thesis concerns the development of semiochemical identification expertise and methodology at the University of Pretoria. The Eucalyptus snout beetle Gonipterus scutellatus was used as a model insect in developing these methods, firstly because it is a known pest in the Eucalyptus forestry industry of South Africa. Secondly, nothing is known about its chemical ecology and lastly, it is a relatively large insect that is easily worked on. Three main techniques were used namely: Electroantennography (EAG), Gas Chromatography Electroantennography Detection (GC-EAD) and Gas Chromatog- raphy Mass Spectrometry (GC-MS). EAG was used to difierentiate and identify certain Eucalyptus species that were expected to contain compounds that may function as either kairomones or allomones for G. scutellatus. The EAG process revealed that G. scutellatus responds more intensely to damaged Eucalyptus leaves as compared to undamaged leaves. The crushed foliage of the known hosts Eucalyptus globulus and E. viminalis gave larger responses than the crushed foliage from a known non-host E. citriodora. We sampled the volatiles from the crushed foliage of these three species and tentatively identified sixteen compounds from the E. globulus volatile profile that was antennally active for G. scutellatus females. The presence of these volatiles were subsequently investigated for E. viminalis and E. citriodora. The green leaf volatiles, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal and aromatic compounds, 2-phenylethanol, benzyl acetate and ethylphenylacetate often gave larger responses than the terpenes such as α-pinene, β-pinene and camphene. Crushed E. globulus leaves contained 2-phenyl ethanol, benzyl acetate, ethylphenylacetate, eucalyptol, α-pinene, (Z)-3 hexenyl acetate, (Z)-3-hexen-1-ol and (E)-2-hexenal that were antennally active. The E. viminalis profile had very little 2-phenylethanol and virtually no benzyl acetate. The E. citriodora volatile profile contained very little (Z)-3-hexen-1-ol, (E)-2-hexenal, 2-phenylethanol, benzyl acetate and ethylphenylacetate. These compounds may influence the host selection behaviour of G. scutellatusfemales. These volatiles can be tested in a behavioural bioassay in order to determine their effect on the Eucalyptus snout beetle G. scutellatus. / Dissertation (MSc)--University of Pretoria, 2010. / Chemistry / unrestricted

Page generated in 0.0612 seconds