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  • 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

Variability in susceptibility of insect pests of stored products to insecticides.

Kumar, Virendra. January 1966 (has links)
Insect pests of public health importance were the first among which the development of highly insecticide resistant strains was shown to be widespread. More recently, numerous instances of resistance among economically important insect pests of growing crops have been revealed. The relative scarcity of reported resistance in stored-products pests is probably a reflection of fewer investigations and fewer instances of continued insecticidal controls. The possible development of resistance at a future date in stored-products pests and the chance that one might avoid such development if it can be foreseen should be adequate justification for the present investigation. It was felt that the occurrence of stored-products pests as isolated islands of population might enhance the selection of resistant strains locally and also allow their eradication if they are discovered, making this a worthwhile area for study. [...]
2

Quantitative evaluation of relative insecticide resistance of Lygus hesperus Knight

Chaudhry, Umruddin, 1927- January 1960 (has links)
No description available.
3

Gene flow as a factor in the evolution of insecticide resistance

Caprio, Michael A January 1990 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1990. / Includes bibliographical references. / Microfiche. / xiii, 114 leaves, bound ill. 29 cm
4

Monitoring insecticide resistance of the western tentiform leafminer Phyllonorycter elmaella (Doganlar and Mutuura) (Lepidoptera: Gracillariidae) in northern Oregon

Shearer, Peter W. 12 December 1990 (has links)
Graduation date: 1991
5

Resistance to pyrethroid and organophosphate insecticides in the pink bollworm, Pectinophora gossypiella (Saunders).

Osman, Abdelgadir Ahmed. January 1989 (has links)
Baseline data on susceptibility levels to azinphosmethyl and permethrin were generated on five field-collected populations of the pink bollworm, Pectinophora gossypiella (Saunders), from Arizona and Southern California, relative to a standard susceptible laboratory strain. The field strains showed less than 2-fold resistance to azinphosmethyl but exhibited variable levels (1.3- to 18.3-fold) of resistance to permethrin. Resistance of pink bollworms to permethrin seems to be correlated with the pattern of insecticide-use prevalent in the localities studied. Strains from Yuma, Phoenix and Westmoreland exhibited highest levels of resistance to permethrin. Synergism of permethrin with an oxidase inhibitor, piperonyl butoxide (PBO), and an esterase inhibitor, S,S,S-tributyl phosphorotrithioate (DEF), produced less than 2-fold synergism in the Yuma strain. Results suggest that nonmetabolic factor(s) may be involved in permethrin resistance of the Yuma field strain since neither PBO nor PBO/DEF combination suppressed resistance completely. It is possible that pink bollworm resistance is at least partially conferred by the khr-gene. Rearing of two field strains collected from Marana and Yuma under insecticide-free conditions resulted in reversion of resistance in four and five generations, respectively, to levels close to that found in the susceptible laboratory strain. Permethrin-resistance in these field strains is unstable and is apparently in its early phase of development. Monitoring of resistance in field strains should be performed preferably in the F₁ generation. Subsequently, selection studies were performed on both larval and adult stages to investigate the capacity of the pink bollworm to develop resistance in both life-stages. Selection of larvae with both azinphosmethyl and permethrin resulted in higher levels of resistance in larvae than in adults. Results suggest that azinphosmethyl possesses a low degree of selectivity for development of resistance in pink bollworm adults. Fourteen to 16 generations of selection with azinphosmethyl and permethrin produced ca. 2- and 9-fold resistance, respectively, in the adult stage. A laboratory-selected strain showing ca. 13-fold resistance was used in reciprocal crosses with a susceptible laboratory strain. The F₁ results suggested that inheritance of permethrin resistance was autosomal and partially dominant. Chi-square analysis of responses of backcross progeny indicated that resistance seems to be conferred by a major gene under the influence of minor gene(s).
6

The molecular genetic basis of insecticide resistance in the peach-potato aphid Myzus persicae (sulzer)

Field, Linda Mary January 1989 (has links)
No description available.
7

Structure and organization of esterase B1 amplification in Culex mosquitoes

Laias, Naima Mahhmoud January 1997 (has links)
No description available.
8

Insecticide resistance£t in the aphid Myzus persicae (Sulzer)

Little, E. J. January 1989 (has links)
No description available.
9

Early detection of insecticide resistance in mosquitoes

Solá, Milagros. January 1900 (has links) (PDF)
Thesis (M.E.S.)--Evergreen State College, 2008. / "June 2008." Title from title screen (viewed 4/8/2010). Includes bibliographical references (leaves 69-71).
10

Characterization of fitness costs associated with insecticide resistance in the diamondback moth, Plutella xylostella, from Hawaii

Ellison, Frances V. January 2007 (has links)
Thesis (M.S.)--University of Delaware, 2007. / Principal faculty advisors: Charles E. Mason and J. Lindsey Flexner, Dept. of Entomology & Wildlife Ecology. Includes bibliographical references.

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