摘要:

One-week-oldRlzyzopertha dominica(F,) adults were kept at 19, 25, 30, and 35°C following gamma irradiation with doses ranging from 5 to 80 kR given at 4200 R/minute. In general, the radiosensitivity of the beetle increased with elevation of the temperature following the treatment. A significant reduction in percent survival and duration of survival period occurred as the postirradiation temperature increased at all exposures. Furthermore, by lowering the temperature at which beetles were kept after irradiation, the onset of mortality was delayed by 5–10 days depending upon the exposure. In the control (unirradiated) group, beetles kept at 30°C lived longer as compared to any other temperature treatment.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.395

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

During a 9-week study in Monroe County, Tennessee, 10 Ellisco® traps forPopillia japonicaNewman when baited with unmated females captured 22,702 males, 20 times more than 10 adjacent traps baited with phenethyl propionate + eugenol (7:3). One female-baited trap caught 10,739 males; one chemical-baited trap caught 517 males. Also, the female-baited traps captured as much as 83 times more males per day as the chemical-baited traps during the early weeks of the test. The 10 female-baited traps caught 87 of 3164 marked beetles released in the study area compared with 8 captured in the adjacent chemical-baited traps. Seasonal ratios of captured males to females were 15.3:1 and 0.4:1 for the female- and chemical-baited traps, respectively. Attractancy of bait females appeared to decline with age.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.397

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

The highest unexplained mortality of immatureMegachile rotundata(F.) occurs in alfalfa-seed fields. Water-soluble saponins from alfalfa leaves, used to line bee brood cells, seemed capable of causing such mortality. Food masses of bee nests from non-alfalfa areas were injected with extracts of leaves from alfalfa plants selected for high or low saponin content. Mortality after injection with these extracts averaged 56.2 and 37.8%, respectively, and that for controls and uninjected cells averaged 29.0 and 5.9%, respectively. This relationship was consistent for 6 different extracts. Purified alfalfa saponins produced bee mortality directly related to saponin concentration. Suggestions to improve bee survival for alfalfa seed production include: selecting low saponin alfalfa lines, increasing bee populations on clovers, and providing alternative leaf forage near alfalfa seed fields.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.399

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

From 1959 through 1964, Federal and State entomologists in Idaho, Oregon, and Washington imported, reared, and releasedPraon pequodorumViereck,Aphidius ervi pulcherBaker,Aphidius ervi erviHaliday, andAphidius smithiSharma&Subba Rao to augment present populations or to replace lost populations of native parasites capable of providing biological control of the pea aphid,Acyrthosiphon pisum(Harris), on peas and alfalfa. As a result, populations of P.pequodorumandA. pulcherhave become increasingly effective against this pest, andA. ervihas become established in coastal Oregon and probably throughout Washington and Idaho. Also, in only 5 years,A. smithihas spread into nearly all the alfalfa- and pea-growing areas of the Pacific Northwest.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.402

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

Muscle tissue from several species of fish collected from 3 sites in the Brazos River Basin of central Texas was analyzed by gas chromatography for insecticide residues. DDT and its metabolites, DDD and DDE, were the only insecticides present in measurable quantities.Residue levels were highest in fish from the Brazos River, a stream which flows through intensively cultivated agricultural land. Residues were lower in fish from the Navasota River, a stream which drains a rangeland area. Lowest residues were present in fish from Somerville Reservoir, a large flood-control and recreational impoundment in a noncropland drainage system.In the Somerville and Navasota systems, several species of gar,Lepisosteusspp., were the only fish containing significant residues of total DDTs. These results suggest that gar might prove useful as an indicator species for determining insecticide contamination in aquatic ecosystems.Residues in all species average considerably less than 1 ppm total DDTs. None of the individuals contained residues that approached the Food and Drug Administration actionable level of 5 ppm total DDTs in the edible portion of fish.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.406

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

Campoletis sonorensis(Cameron) males exhibited 4 main elements of courtship behavior when exposed to females or odor-laden air from females. The 4 courtship behavioral elements were: orientation, wing vibration, antennal touching, and attempted copulation. Odor from females lowered the threshold for the behavioral elements of courtship exhibited by males.Wing vibration may aid the male in orientating toward the odor source. Actual orientation of the male to another insect appeared to involve sight, while antennal touching was used by the male to position itself with respect to the female. Orientation and attempted copulation with males occurred as readily as with females in the presence of the female pheromone.Both virgin and mated males responded to both virgin and mated females. Multiplemated older females were less active in eliciting male courtship behavior. No region of the female could be isolated with respect to pheromone production. Ethyl acetate extracts of females were active in eliciting the courtship behavior of males.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.409

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

Releases ofMicroterys flavus(Howard) in selected citrus groves in south Texas reduced populations of brown soft scale,Coccus hesperidumL., for prolonged periods compared with groves exposed to chemical control. The theoretical potential of this encyrtid parasite is such that a single gravid female could produce sufficient offspring in 6–7 weeks to destroy 1,089,300 scales. Procedures might be developed that would overcome adverse effects on the parasites and assure the success of compensatory releases of this parasite for control of brown soft scale.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.414

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

Nine species of naturally occurring hymenopterous parasites were recovered fromCnephasia longana(Haworth) in western Oregon. The most commonly recovered parasites were the braconidsAgathis cincta(Cresson),Bracon hyslopi(Viereck),B. gelechiae(Ashmead), and the ichneumonidEnytus eureka(Ashmead). Other parasites reared were the ichneumonsIschnus-inquisitorius atriceps(Cresson),Itoplectis conquistor(Say),I. quadricingulata(Provancher),Phytodietus burgessi(Cresson), andTranosema interrupta pterophorae(Ashmead).The incidence of parasitism was generally low, and larvae were not attacked until late in their activity period. There appears to be a preference differential between ichneumons and braconids in attacking omnivorous leaftier larvae infesting different host plants. None of the parasites introduced and released against the omnivorous leaftier in Oregon nearly 20 years ago have become established.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.419

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

When host plants ofHeliothis zea(Boddie) andH. virescens(F.) were studied in a 2500-acre area near Brownsville, Texas in 1970,H. zeawas found primarily on grain sorghum during the spring and on cotton during June–August. Cotton was the primary cultivated host ofH. virescens, but in the spring and fall, it was also common on such uncultivated bosts asNicotiana repandaWilld.,Verbena neomexicana(Gray) Small, andRuellia runyoniiTharp&Barkley; in addition,H. virescenswas found onAubtilon trisulcatum(Jacq.) Urban in tbe fall.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.424

出版商:Oxford University Press    

年代:1972

数据来源: OUP

摘要:

Phytoseiulus persimilisAthias-Henriot was introduced on hop plants at 10, 20, and 30 per plant for control of the twospotted spider mite,Tetranychus urticaeKoch.P. persimilisbecame established on hops but the predator-prey populations were retarded by an infestation of the hop aphid,Phorodon humuli(Schrank). Phosalone when applied to reduce aphid numbers also killedP. persimilisbut permitted survival ofTyphlodromus occidentalisNesbitt, a native phytoseiid predator ofT. urticaeon hops. A laboratory study of the interaction ofP. persimiliswithT. occidentalisand the coccinellidsStethorus punctillumWeise and the convergent lady beetle,Hippodamia convergensGuérin-Meneville, indicated thatT. occidentalisandS. punctillumfed on eggs and larvae ofP. persimilis.H. convergensfed on all stages ofP. persimilis. In the field,T. occidentalisfed onP. persimiliseggs and larvae.P. persimilisdid not feed onT. occidentaliseggs or larvae.T. occidentalisappears to be a better candidate thanP. persimilisfor control ofT. urticaeon hops.

ISSN:1754-5692    

DOI:10.1093/ee/1.4.431

出版商:Oxford University Press    

年代:1972

数据来源: OUP