摘要:

Flight range studies were begun in July 1972 to determine the flight capability of femaleSimulium slossonaeDyar and Shannon. This information was necessary to conduct successful vector control work involvingLeucocytozoon smithi(Laveran and Lucet 1905) Sambon, 1908 transmission in turkeys.Simulium slossonaewas found to commonly travel up to 4 mi. following an infective blood meal. Throughout the 10–wk study only 4 flies were found to travel 6 mi. and 3 traveled 8 mi. This number of flies moving 6 and 8 mi. would probably not be critical from the standpoint of controllingL. smithiin turkeys.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.365

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

In areas with high lead emission from the exhaust of vehicles, insects contained averages of 10.3, 15.5, and 25.0 ppm lead (oven dry weight) for species that suck plant juices, chew plant parts, and prey on other insects respectively, indicating a biological concentration of lead from herbivore to carnivore trophic levels. In low lead emission areas insects in the same feeding categories had average lead contents of 4.7, 3.4, and 3.3 ppm respectively and showed no significant differences.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.370

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

In an attempt to determine the primary physical factors affecting the fall migration of the Egyptian alfalfa weevil, a multiple regression analysis, based on a 2-year study in north-central California, was conducted. Physical factors monitored on a daily basis were temperature, wind, cloud cover, evaporation, and precipitation. Four aspects of daily temperature were considered: maximum, minimum, difference between maximum and minimum, and average. Total wind movement and direction was studied. The average number of adult weevils recorded per square yard of trap per sample day was used as the dependent variable and the above-mentioned physical factors as the independent (predictor) variables. We analyzed the data for both study years and obtained a total reduction of 77.6% in the residual variance the first year and 71.3% for the 2nd. Daily temperature difference was by far the single most important factor in reducing the residual variance and, hence, appears to be the most important factor influencing the fall weevil migration.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.373

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

Groups of progeny produced by virgin and mated female parasites,Lysiphlebus testaceipes(Cresson), and reared on the biotype C greenbug,Schizaphis graminum(Rondani), displayed a similar increase in length of development periods, from 9–13 days to 15–21 days, and a similar, statistically significant, decline in the numbers of successfully emerged adults when reared at 24.0 and 18.3°C under controlled growth chamber conditions. At 12.8°C progeny of virgin females developed over a period of 26–46 days and progeny of mated females developed over 26–35 days. The difference in the number of emerged adult progeny of both parent types between 24.0 and 12.8°C was highly significant. Copulation was successful with similar progeny sex ratios at all 3 temperatures. Virgin female parasites were observed to produce only males. Manipulation of parasitized greenbugs and mummies had no significant deleterious effect on progeny survival.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.377

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

A laboratory study of the influence of various combinations of light, dark, and temperature on adultChrysoteuchia topiaria(Zeller) revealed that the rhythm of emergence was exogenous and was initiated by changes of temperature or by the transition from dark to light corresponding to dawn in nature. Thus, the time of emergence in nature is probably determined by an interaction of photoperiod and temperature. In a field test, virgin females were attractive to males in a rhythmic manner whereby 71% of the males were attracted to the females between 0700 and 1100. Cool and cloudy weather reduced the number of responding males.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.380

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

Estimation of gypsy moth,Porthetria dispar(L.) male mating potential has been made using box-type disparlure-baited traps. This potential, estimated by the reciprocal of the time elapsed before virgin females mated during the natural gypsy moth flight, was proportional to 22-h trap catches. Seasonal trap catches tended to be proportional to population as estimated by counts of pupae under burlap bands, with estimates adjusted for numbers of oak trees in 0.1-ha plots.Trap catches were highest when traps were adjacent to large trees and 1.5 m or less above the ground.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.383

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

Boll weevils,Anthonomus grandisBoheman, captured in traps were not always representative of field populations with respect to sex ratio and status of diapause. From June to mid-winter, the ratios of captured females to males are higher than they are in field populations. In the fall, the percentage of boll weevils in the field that are in diapause is higher than the percentage among those captured in traps.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.386

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

Blacklight traps were operated for 43 months at a density of 3 per square mile on an isolated tropical island, St. Croix, U. S. Virgin Islands, to determine the effect on populations of 25 insect species. Subsequently, the density of traps was reduced to 0.3 per square mile for 18 months, and changes in the collections were noted.The test species were:Agrius cingulatus(F.),Callionima ramsdeni(Clark),Eumorpha vitis(L.),Hyles lineata(F.),Manduca rustica harterti(Rothschild),Manduca sexta(L.),Xylophanes pluto(F.),X. tersa(L.),Heliothis virescens(F.),H. zea(Boddie),Ecpantheria icasia(Cramer),Gryllus assimilis(F.),Microcentrum triangulatumBrunner,Neoconocephalus triops(L.),Schistocerca pallens(Thunberg),Acrosternum marginatum(Palisot De Beauvois),Loxa pilipesHorvath,Nezara viridula(L.),Jadera rufofuscaBarber,Bothynus cuniculus(F.),Phyllophaga microphyllaMoser,P. portoricensis(Smyth),Calosoma alternans alternans(F.),Conoderussp. andLacon subcostatus(Candeze).Many species had decreased populations as measured by BL trap collections during the 43 months, and within a year after the trap density was reduced most had surges to population levels as high or higher than those recorded during masstrapping. Lepidopteran population indices were more affected than indices of other orders. Generally, most decreases and increases in populations appeared to be related to the trapping, but the numbers of some species that were removed by the traps were so low that any effect was indirect. Blacklight traps have a potential as a supplement for other control measures or possibly as a control themselves if the trap area is sufficiently large or sufficiently isolated.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.389

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

The effects of parasitism byBathyplectes curculionis(Thomson) onHypera postica(Gyllenhal) development and activity were studied at 25–26°C. Larvae of each instar were parasitized and the number of days required for development to the cocoon stage was compared with that of unparasitized larvae of the same age. The development time for larvae parasitized during the 3rd or 4th stadium was longer than that for unparasitized larvae. No significant difference existed between the time for development of larvae parasitized as 1st or 2nd instars and that for unparasitized larvae. The activity rate and distance traveled for unparasitized and parasitized larvae did not differ. All attempts to visually separate parasitized from unparasitized larvae were unsuccessful. Yellowish larvae had a higher percentage parasitism than green larvae, but the difference was not great enough to be of practical value.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.396

出版商:Oxford University Press    

年代:1974

数据来源: OUP

摘要:

Trichogramma californicumNagaraja and Nagarkatti deposited eggs into various solutions encapsulated in paraffin droplets. Oviposition occurred in physiological saline, Neisenheimer's saline solution, and some mixtures of amino acids but not into distilled water. The first paraffin droplet oviposited into byT. californicumreceived all the eggs. As many as 500 parasite eggs were deposited into one artificial egg.

ISSN:1754-5692    

DOI:10.1093/ee/3.3.399

出版商:Oxford University Press    

年代:1974

数据来源: OUP