Irving Keiser
United States Department of Agriculture
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Irving Keiser.
Journal of Insect Physiology | 1968
R. E. Doolittle; Morton Beroza; Irving Keiser; Esther L. Schneider
Abstract The structure of cue-lure [4-(p-hydroxyphenyl)-2-butanone acetate], a potent attractant for the male melon fly, Dacus cucurbitae Coquillett, was systematically altered by replacing atoms of hydrogen with deuterium in various parts of the molecule. The positions of substitution were established from the nuclear magnetic resonance spectra of the compounds. The deuterium substitutions did not affect the attractiveness of the compound to the male melon fly. The far i.r. spectra, believed by some investigators to be related to the olfactory properties of molecules, were determined for the deuterated and undeuterated compounds. Shifts in spectral position did occur as a result of deuteration. However, no relationship between olfactory response and absorption in the far i.r. region was found.
Environmental Letters | 1974
Irving Keiser; Richard M. Kobayashi; Doris H. Miyashita; Ernest J. Harris; D. L. Chambers
Abstract Volatilization of cue-lure, methyl eugenol, and trimedlure, the synthetic lures for male melon flies, Dacus cucurbitae Coquillett, oriental fruit flies, D. dorsalis Hendel, and Mediterranean fruit flies, Ceratitis capitata (Wiedemann), respectively, was found to take place at different rates: cue-lure showed a low level of volatility; trimedlure is comparatively very volatile; methyl eugenol is intermediate but was more similar to cue-lure than to trimedlure. Traps baited with even trimedlure would need only infrequent servicing if a lure reservoir were incorporated with the wick, and if the reservoir were made large enough to contain adequate supplies of trimedlure.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1982
Irving Keiser; Mohammad Ashraf; James A. Silva; Ernest J. Harris
Abstract The 3 tephritids in Hawaii of economic importance, namely the Mediterranean fruit fly (medfly), Ceratltls capltata (Wiedemann), the oriental fruit fly, Dacus dorsalis Hendel, and the melon fly, D. cucurbitae Coquillett, showed marked differences in species‐, age‐, and sex‐specific susceptibilities to CO2 anesthetization. Mortalities for medflies exposed to CO2 increased more with time than did mortalities for the other 2 species. Older medflies and oriental fruit flies were more susceptible to CO2 exposure than were younger flies. Female medflies and oriental fruit flies were generally affected more by CO2 exposure than were males. Melon files were the least affected of the tested species by anesthetization with CO2.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1976
Mohammad Ashraf; Irving Keiser; Ernest J. Harris
Abstract Male melon flies, Dacus cucurbitae Coquillett, treated with a single dose of the chemosterilant tepa (tris(l‐aziridinyl) phosphine oxide), or with gamma irradiation, either single or fractionated doses, did not differ significantly in sexual competitiveness as determined by percentage hatch of eggs. Mating competitiveness of males treated by either method ranged from 53 to 66% of that of untreated males. In another study, melon flies (males and females) sterilized with 0.0125% tepa, the threshold dose for both sexes, completely suppressed a population when the ratio was 16:16:1:1 (sterile males‐sterile females‐untreated males‐untreated females) as determined by no egg hatch.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1988
Irving Keiser; Sana Ullah Khattak; Mohammad Ashraf; James A. Silva
Abstract Mortalities of laboratory‐reared adult Mediterranean fruit flies, melon flies, and oriental fruit flies fed hydrolyzed protein were less than those fed whole protein or no protein. Dosage mortalities of these species treated with malathion showed differential toxicities for each species similar to the diet‐specific longevity relationships. Species‐specific sex differences in laboratory mortalities of adult flies were noted: male Mediterranean fruit flies lived longer than females; female melon flies and female oriental fruit flies lived longer than males.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1987
Irving Keiser; Mohammad Ashraf
Abstract The 3 Tephritids in Hawaii of economic importance, namely oriental fruit flies, Dacus dorsalis Hendel, Mediterranean fruit flies (medfliea), Ceratltis capitata (Wiedemann) and melon flies, D. cuourbitae Coquillett do not survive more than 2–3 days as adults kept at ambient temperatures (75°‐85°F) when deprived of sugar. When adults are deprived of sugar in a cold environment (40oF) for up to 10 days (tests terminated) there are survivors at different age levels, depending upon periods of exposure. Young flies generally withstand food deprivation in the cold environment longer than older flies. This discovery has important implications regarding introduction and spread of new infestations. Theoretically, a gravid female might survive a trip in a cold storage area in the hold of a cargo vessel with fruit and start a new infestation when the fruit is removed and the adult female returned to ambient temperature at the ships destination.
Archive | 1981
Irving Keiser; Martin Jacobson; James A. Silva
In 1976 we reported1 that certain perfume fixatives controlled the release of trimedlure,2 an attractant of male Mediterranean fruit flies, Ceratitis capitata (Wiedemann), and thereby enhanced the duration of effectiveness of this lure. The perfume fixatives were evaluated in an olfactometer stocked with laboratory massreared flies, and included tonalid, musk R-1, ambrettozone, galaxolide, astrotone, hibiscolide, phantolid, and musk BRB.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1978
Irving Keiser; Mohammad Ashraf; Ernest J. Harris; James A. Silva
Abstract Laboratory‐reared virgin females of 3 species of Tephritidae oviposited significantly fewer eggs than similar previously mated females. Melon flies, Dacus cucurbitae Coquillett, were most affected (3.0X more eggs for mated females), and Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were least affected; oriental fruit flies, D. dorsalis Hendel, were in between. Numbers of eggs laid by females mated with males treated either with tepa in drinking water or with gamma irradiation were not significantly different from those laid by females mated with untreated males. Thus, mating per se was important in enhancing oviposition regardless of the fertility of the males.
Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering | 1976
Mohammad Ashraf; Irving Keiser; Ernest J. Harris
Abstract When oriental fruit flies, Dacus dorsalis Hendel, of mixed sex were supplied with sugar treated with 0.026% thiotepa for 3 days after eclosion no eggs hatched. Only 0.2% hatched when the dose was 0.0065% thiotepa. A dose of 0.10% was toxic to the insects. Mediterranean fruit flies, Ceratitis capitata (Wiedemann), were not completely sterilized at any dose tested although eggs hatched when flies of mixed sex were supplied with 0.051% thiotepa, and only 0.4, 0.7, 0.7, and 0.8% hatched when the dose was 0.051, 0.026, 0.013 or 0.0065%, respectively. A dose of 0.82% was toxic. Mortality of both species was lower among treated flies that were fed normally after treatment, especially among those treated at or near the threshold dosages, than among untreated flies. Also, when both species were deprived of food and water, treated flies survived longer than untreated flies. Treated oriental fruit fly males were 84% as competitive in mating with females as their untreated counterparts; treated male Mediterr...
Journal of Economic Entomology | 1974
Irving Keiser; Richard M. Kobayashi; Doris H. Miyashita; Ernest J. Harris; Esther L. Schneider; D. L. Chambers