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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.
21

Development of traps for adult Glischrochilus quadrisignatus (Say) (Coleoptera:Nitidulidae) and investigation of olfactory responses to volatile components of corn, raspberry and tomato

Bourchier, Robert S. January 1986 (has links)
No description available.
22

Effects of harvesting aquatic bait species from a small West Virginia stream (part I); and, Crayfish marking with flourescent pigment (part II)

Brandt, Thomas M. January 1974 (has links)
Fluorescent granular pigment sprayed with 738 g/cm² (105 p.s.i .) for 5, 10, 20 second intervals was used to mark crayfish in a laboratory study. The pigment was retained by 100% of the unmolted crayfish 35 days after treatment and by 65% of the crayfish 56 days after treatment. Crayfish which were induced to molt after being sprayed generally lost the fluorescent pigment during the molt. Mortality, (2%), due to the marking procedures was minimal. / Master of Science
23

The effects of deuterating an attractant of the American cockroach, Periplaneta americana L., as a test for the frequency theory of olfaction

Kuo, Chung-Kuo January 2011 (has links)
Vita. / Digitized by Kansas Correctional Industries
24

Three feeding stimulants in the alfalfa steam distillate for the alfalfa weevils, (Hypera postica (Gyl.))

Chiou, Rita Hway-Ying,1949- January 1979 (has links)
Call number: LD2668 .T4 1979 C54 / Master of Science
25

Assessment of toxic baits for the control of ants (Hymenoptera : Formicidae) in South African vineyards

Nyamukondiwa, Casper 12 1900 (has links)
Thesis (MScAgric (Conservation Ecology and Entomology))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Ant infestations comprising the Argentine ant Linepithema humile (Mayr), common pugnacious ant Anoplolepis custodiens (F. Smith) and cocktail ant Crematogaster peringueyi Emery are a widespread pest problem in South African vineyards. Integrated Pest Management (IPM) programmes aimed at suppressing the problematic honeydew excreting vine mealybug Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) on grapes must include ant control to optimize the effectiveness and efficacy of mealybug natural enemies. If ants are eliminated, natural enemies are able to contain mealybugs below the Economic Threshold Level (ETL). Current strategies for ant control are limited and generally include the application of long term residual insecticides that are detrimental to the environment, labour intensive to apply and can disrupt natural biological control if applied incorrectly. A more practical method of ant control using low toxicity baits was therefore investigated. Field bait preference and bait acceptance assessments aimed at determining bait repellency and palatability, respectively, were carried out during spring, summer and autumn in three vineyards of the Cape winelands region during 2007/08. Five toxicants comprising gourmet ant bait (0.5%), boric acid (0.5%), fipronil (0.0001%), fenoxycarb (0.5%) and spinosad (0.01%) dissolved in 25% sugar solution were tested against a 25% sucrose solution control. Gourmet ant bait was significantly more preferred and accepted by all ant species than the other baits. Laboratory bait efficacy assessments using four insecticides (gourmet, boric acid & spinosad) at concentrations of 0.25; 0.5; 1; 2 and 4 times the field dose and fipronil at 0.015625; 0.03125; 0.0625; 0.125; 0.25 times the field dose were carried out. Results revealed that boric acid (2%), gourmet ant bait (2%) and fipronil (1.0 X 10-5%) exhibited delayed toxicity for L. humile and C. peringueyi while spinosad (0.01%) showed delayed action on L. humile. Field foraging activity and food preference tests were also carried out for the three ant species during 2007/08. Foraging activity trials revealed that vineyard foraging activity of L. humile is higher relative to A. custodiens and C. peringueyi. This means fewer bait stations are required for effective L. humile control making low toxicity baits a more affordable and practical method of controlling L. humile than the other two ant species. Food preference trials showed that L. humile and C. peringueyi have a high preference for sugar while A. custodiens significantly preferred tuna over other baits. However, all ant species had a preference for wet baits (25% sugar water, 25% honey, tuna & agar) as opposed to dry ones (fish meal, sorghum grit, peanut butter & dog food). This research concludes that low toxicity baits show potential in ant pest management and can offer producers with a more practical, economical and environmentally friendly method of ant control which is compatible with vineyard IPM programmes. / AFRIKAANSE OPSOMMING: Mierbesmetting wat uit die Argentynse mier Linepithema humile (Mayr), die gewone malmier Anoplolepis custodiens (F. Smith) en die wipstertmier Crematogaster peringueyi Emery bestaan, is ’n plaagprobleem wat wydverspreid in Suid-Afrikaanse wingerde voorkom. Programme vir geïntegreerde plaagbeheer (GPB) wat daarop gemik is om die wingerdwitluis Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) – wat ’n probleem is weens die heuningdou wat dit afskei – op druiwe te beheer, moet mierbeheer insluit om sodoende die uitwerking en doeltreffendheid van die witluis se natuurlike vyande die beste te benut. As miere uitgeskakel kan word, sal dit vir die natuurlike vyande moontlik wees om die witluis sodanig te beheer dat dit onder die ekonomiese drempelvlakke (EDV) bly. Huidige strategieë om miere te beheer, is beperk en sluit gewoonlik die toediening van insekdoders in wat lank neem om in die grond af te breek, wat skadelik vir die omgewing is, waarvan die toediening arbeidsintensief is en wat die natuurlike biologiese beheer kan versteur indien dit verkeerd toegepas word. Daarom is ’n meer praktiese metode ondersoek waar miere deur die gebruik van lae toksisiteit lokase beheer word. Ondersoeke na lokaasvoorkeure en lokaasaanvaarbaarheid in die praktyk, wat daarop gemik is om te bepaal of die lokaas onderskeidelik afstootlik en smaaklik bevind word, is oor lente, somer en herfs in drie verskillende wingerde in die Kaapse wynlandstreek gedurende die 2007/08-seisoen uitgevoer. Vyf gifstowwe, bestaande uit gourmet ant bait (0.5%), boorsuur (0.5%), fiproniel (0.0001%), fenoksiekarb (0.5%) en spinosad (0.01%) wat in ’n 25%-suikeroplossing opgelos is, is getoets teenoor ’n kontrole wat uit ’n 25%-sukrose-oplossing bestaan. Al die mierspesies het gourmet ant bait bo die ander lokase verkies en aanvaar. In die laboratorium is ondersoeke gedoen om die doeltreffendheid van die lokase te bepaal deur vier insekdoders (gourmet ant bait, boorsuur en spinosad) te gebruik in konsentrasies van 0.25; 0.5; 1; 2 en 4 keer die dosis in die praktyk en fiproniel teen 0.015625; 0.03125; 0.0625; 0.125; 0.25 keer die dosis in die praktyk. Resultate het getoon dat boorsuur (2%), gourmet ant bait (2%) en fiproniel (1.0 X 10-5%) vertraagde toksisiteit getoon het vir L. humile en C. peringueyi, terwyl spinosad (0.01%) ’n vertraagde uitwerking getoon het op L. humile. Toetse om kossoekaktiwiteite in die praktyk en die voedselvoorkeure van die drie mierspesies te ondersoek, is ook gedurende die 2007/08-seisoen gedoen. Proewe oor kossoekaktiwiteite het getoon dat hierdie aktiwiteite in die wingerd by L. humile hoër is in verhouding met A. custodiens en C. peringueyi. Dit beteken dat minder lokaasstasies nodig is om L. humile doeltreffend te beheer en lei daartoe dat lae toksisteit lokaas ’n beter manier is om L. humile te beheer as die ander twee mierspesies. Proewe oor voedselvoorkeure het aangedui dat L. humile en C. peringueyi ’n groot voorkeur toon vir suiker, terwyl A. custodiens ’n duidelike voorkeur vir tuna het. Alle mierspesies het egter ’n voorkeur vir nat lokaas (25% suikerwater, 25% heuning, tuna en agar), eerder as droë lokaas (vismeel, sorghumgruis, grondboontjiebotter en hondekos) getoon. Uit hierdie navorsing word afgelei dat lae toksisteit lokaas potensiaal toon in mierbeheer en dat dit produsente ’n meer praktiese, ekonomiese en omgewingsvriendelike metode van mierbeheer kan bied wat met GPB-programme in die wingerd versoenbaar is.
26

Termite control for homeowners

Baker, Paul B. 03 1900 (has links)
9 pp. / Termites are considered Arizona's number one urban pest. All termites can be placed into 3 broad categories based on their habitat: damp-wood, dry-wood and subterranean. In Arizona, damp-wood and dry wood termites are not major wide spread problems but can be under selected conditions. Subterranean termites on the other hand are considered one of our major urban pests. Detection of the presence of termites in many cases can be difficult to do. A discussion of construction practices is presented to keep termites from invading your home. Control technologies such as a pre and post-treatment using a termiticide, physical barriers and baiting systems are presented.
27

Assessment of sodium fluoroacetate (1080) in baits and its biodegradation by microorganisms.

Kirkpatrick, Winifred E. January 1999 (has links)
In Western Australia dried meat baits containing 1080 are used extensively by agricultural and conservation organisations to control foxes and dingoes for the protection of agricultural production and native fauna. Field trials were conducted to assess 1080 loss from dried meat baits and this required the analysis of over five hundred baits. Because of this large number of baits it was essential to have a simple and efficient 1080 extraction procedure and method of 1080 analysis. In this study three methods of 1080 extraction and the new bioassay method for 1080 analysis were investigated. A simple and cost-effective 1080 extraction method using water with a 98% 1080 recovery rate was developed and modifications to the bioassay method were made.Factory-produced 1080 dried meat baits were laid in the field during different seasons at four locations in Western Australia, samples were collected over time and analysed for 1080 content using the bioassay. Rainfall was recorded and temperature data was collected for each site. Baits were exposed to the elements but were placed in mesh or wire cages to restrict invertebrate attack and prevent removal by vertebrates. Some baits were placed on the surface and others were buried. Initially 1080 loss from baits from all 4 sites was minimal, ranging from 0 - 21% at day 7 - 9. Further loss was gradual even when rainfall was recorded. Generally baits had to be exposed to at least 50 mm of rain before 1080 loss increased to 50%. At some sites baits continued to remain toxic to foxes even after long exposure. The mean 1080 content of baits from the Carnarvon site at day 226 was 2.0 mg (55% of the mean 1080 content of baits at day zero) with 137 mm of rainfall recorded for that period. Loss of 1080 from baits buried occurred at a faster rate than from baits placed on the surface during the same time period. By day 14 no 1080 was ++ / detected in the buried baits compared to the 68% detected in the surface baits. Under certain conditions 1080 loss from baits was minimal. Levels of 1080 in baits from Nangeen Hill remained fairly constant during the months of September to December 1995, and again during February to April 1996.Gastrolobium plant tissue and soil samples from the southwest of Western Australia were investigated for the presence of 1080 degrading microorganisms. Microbes were isolated and individually tested in solution containing 1080 as the sole carbon source. Isolates which showed 1080 degrading ability were further tested for their degrading efficiency in McClung carbon-free solution with added 1080 as the sole source of carbon and in factory 1080 waste solution, at 1080 concentrations of 20 and 200 mM. The effect of temperature on their rate of degradation was also examined. Thirteen isolates (7 fungi and 6 bacteria) showing varying degrees of 1080 degrading ability were obtained. Rates of 1080 degradation varied among isolates but were highest in the factory waste solution at the 20 mM concentration and in the McClung solution, where 1080 was the sole source of carbon, at the higher concentration of 200 mM. The most efficient isolates OSK and 10H (both Pseudomonas species) degraded all the 1080 present in sterile factory waste solution up to 20 mM 1080 concentration in 4 days and the isolate 1AF (Fusarium oxysporum) degraded 93% of 200 mM 1080 in the McClung solution in 9 days. The optimum temperatures for 1080 degradation were 30 degrees celsius and fluctuating ambient temperatures of 15 28 degrees celsius.
28

Efficacy evaluation of Mohlolo Insecticide Bait on German Cockroach, Blattella Germanica L

Mbowane, Clarah January 2014 (has links)
Thesis (M.Sc. (Plant Production)) -- University of Limpopo, 2014 / In most cases the discipline plant protection is restricted to the protection of propagules, the plants and their produce in storage, while excluding the protection of processed (cooked) food from contaminants. Generally, the German cockroach (Blattella germanica L.) is a serious contaminant of processed food and had recently been viewed as a pest worthy of control in plant protection when viewing the entire value chain of agricultural commodities. Due to the nature of the pest, it is quite difficult to control using registered agrochemicals on the market. An entrepreneur in the rural areas of Limpopo Province developed bait for cockroach control, which was code named Mohlolo during efficacy trials. The use of baiting in cockroach management is currently the sought after approach in the world where cockroaches are problematic. Bait has the advantage over liquid or dust formulations because baiting requires shorter service, has shown increased efficacy, and has reduced environmental contamination. The objectives of this study were to determine whether the effect of MIB would be age related in the suppression of populations of B. germanica under laboratory conditions, and also to investigate whether MIB would reduce populations of B. germanica in residential areas. Five concurrent B. germanica age-related experiments were run in a complete randomized design. 1-d, 2-d, 3-d, 4-d, 5-d old nymphs and adult German cockroach experiments were conducted at Limpopo Agro-Food Technology Station (LATS) laboratory, (53’21,41” S/29 23o 44’19,95”E) hosted at the University of Limpopo. Each age group consisted of 10 nymphs and was put in 250 cm3 container that contained xv Mohlolo insecticide bait (MIB). One gram (1 g) of Mohlolo insecticide bait and moistened cotton wick were put at the bottom centre of the 250 cm3 containers containing nymphs based according to their respective ages. Residential experiments were conducted at UL student apartments. Two Bait containers were then placed in the kitchen, lodge, bathroom and bedroom. In the kitchen MIB containers were put behind the cooking stove and refrigerator, in the lodge the bait was placed next to the study table (because most study tables are also used during the eating time). In the bathroom the baits were put next to toilet seat and lastly in the bedroom, the bait was placed next to study table. According to the results, 100% mortality of 1-, 2-, 3-, 4-, 5-days nymphs and adult B. germanica was obtained after 7th, 2nd 3rd 3rd and 4th day, whereas LT50 values ranged from half a day to one and half (1.5) day. The study also demonstrated that B. germanica populations had high LT50 and LT100 values in residential areas compared to LT50 and LT100 values obtained in the laboratory experiments. This is probably due to the fact that residential areas that have low levels of sanitation availed the cockroaches with an opportunity to choose from many foods hence, it reduced the probability for cockroaches to feed on Mohlolo insecticide bait in the respective apartments. Results of this study showed that, Mohlolo bait toxicity and effectiveness as a control agent can reduce infestation of cockroaches in all developmental stages when applied at small quantity. Providing results of this study would provide information on resistance and tolerance of B. germanica nymphs and adult population against MIB in the xvi laboratory and residential areas. It would also provide biological information on the efficacy of MIB against the German cockroaches.
29

Product formulations and in vitro-in vivo evaluation of 1) topical insect repellent formualtions against mosquitoes; 2) oral sustained release formulations of cefaclor and pentoxifylline in adults

Chou, Joyce Tian-wei 20 November 1995 (has links)
Graduation date: 1996
30

Olfactory response of Lygus hesperus Knight to chemicals naturally found in alfalfa

Zaugg, Jerry Lynn, 1942- January 1971 (has links)
No description available.

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