Authors:Vlatka Rozman, Irma Kalinovic and Anita Liska
Huang, Y., Ho, S. H., Lee, H. C., Yap, Y.L., 2002. Insecticidal properties of eugenol, isoeugenol and methyleugenol and their effect on nutrition of
We studied a benthic invertebrate assemblage of a stream that passes through pristine, rural, suburban and urban areas of a municipality located in southeastern Brazil to investigate a possible relationship between this assemblage structure and urbanization. The environmental variables and fauna structure were analyzed in a spatial and temporal scale, sampling the four sites in a dry and wet season. We found a clear spatial pattern, with higher similarity between sites from rural and suburban area that presented intermediate environmental characteristics. The pristine site showed in both seasons the lowest values of alkalinity and fecal coliform. On the other hand, the site located in the urban area showed the lowest concentration of dissolved oxygen and higher of suspended solids, ammonia and fecal coliform. The extreme values of these three variables occurred in the wet season, probably related to the high rainfall values. The benthic invertebrate fauna structure followed the same longitudinal and seasonal pattern found for the environmental variables. The site in urban area showed the lowest richness, diversity and evenness, with a dominance of two groups resistant to adverse environmental conditions (Oligochaeta and Orthocladiinae) and absence of more sensitive groups (Coleoptera, Ephemeroptera and Trichoptera). The increase drag of the substrate and associated invertebrates can be responsible for the lower abundance and richness observed in the wet season. The environmental variables that best defined the differentiation between sites (dissolved oxygen, organic suspended solids and fecal coliform) related directly to urbanization effects, like dump effluents and removal of riparian vegetation.
Authors:W. D. James, A. T. Showler, J. K. Westbrook and J. S. Armstrong
Stable isotope markers have been used to study animal nutrition for several decades and more recently to study the foraging
and cultural habits of imported fire ants. In this work, we have extended that effort to evaluate the potential for marking
boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), with the rare earth element samarium to aid in studies of insect invasion and pest eradication protocols. Neutron activation
analysis (NAA) was performed on the marked boll weevils as well as plant material from the cotton squares on which the insects
were fed. Samarium levels in non-dosed insects average about 20 ng/g or about 100 pg total element per insect. Our computed
average determination limit was 36 pg samarium/weevil. The determination limit for cotton plant squares and leaves averaged
3.5 ng/g and 8.2 ng/g, respectively. These initial results indicate the NAA method is capable of identifying individual marked
insects which have assimilated 1 ng of samarium, a ten-fold increase in content over average blank values.
., Draganic, M., Baca, F. and Kaitovic, Z. (1994): Rasprostranjenost i stetnost Diabrotica virgifera virgifera LeConte (Coleoptera, Chrysomelidae) nove stetocine kukuruza u Jugoslaviji. Zastita bilja, Vol. 45, 19
Authors:K. Mohammadpour, A. Avand-Faghih and A. Hosseini-Gharalari
Avand-Faghih , A. ( 1996 ): The biology of red palm weevil, Rhynchophorus ferrugineus Oliv . (Coleoptera: Curculionidae) in Saravan region (Sistan and Balouchistan Province, Iran). Appl. Entomol. and Phytopathol. 63 , 16