摘要:

Before the rainy season, eggs ofDiabrotica virgifera zeaeKrysan and Smith were found to be dormant in nonirrigated fields in Jalisco, Mexico. At this time, soil moisture was about 11.5%. Embryo development began in June, when the soil moisture was about 20%. Initial egg hatch occurred during the first week of July. There appeared to be no difference in the rate of development betweenD. v. zeaein central Mexico andD. v. virgiferaleConte in the U.S. corn belt, but all events in the development ofD. v. zeaein nonirrigated fields occurred ca. 1 month later than the same events in the development ofD. v. virgiferain the corn belt. The population ofD. v. zeaeappeared to be adapted to several different cropping practices: in May, before the rainy season began, we found eggs in diapause, larvae, or adults in different fields depending upon the availability of soil moisture and the time of planting. Diseasesand predatorsappearedto have a greater influenceon the populationdynamics ofD. virgiferain Mexico than in the corn belt.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1078

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Chemical, chromatographic, and mass spectral analyses of the heptane extracts of excised femaleHeliothis subflexaovipositors showed that the females produce 11 compounds that are analgous to knownHeliothisspp. sex pheromones. Seven of these compounds have been previously identified from femaleH. virescens. In addition to these seven, femaleH. subflexaproduce the (Z)-isomers of 7-, 9-, and 11-hexadecen-1-ol acetate and 1-hexadecanol acetate. The ratio of (Z)-11-hexadecenal to (2)-9- hexadecenal found inH. subflexawas significantly different from ratios found in other femaleHeliothisspp. Chromatographic analyses of the heptane extracts of the ovipositors of F1females resulting from theH. subflexa(♀) ×H. virescens(♂) cross and female progeny form F1hybrid females backcrossed 34 times toH. virescensshowed that they both produce a blend of pheromonal compounds that is qualitatively and quantitatively similar to compounds produced byH. virescensfemales. Field and laboratory behavioral studies indicated that the C16acetates and the ratio of (Z)-11-hexadecenal: (Z)-9- hexadecenal secreted by femaleH. subflexaplay significant roles in the maintentance of the specificity of the femaleH. subflexapheromonal signal.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1084

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Snail fecal content studies were conducted on the citrus tree snail,Drymaeus dormani(Binney). The fecal content consisted primarily of sooty mold and other mycelia, all stages ofPhyllocoptruta oleivora(Ashmead), including its spermatophore,Dialeurodes citriAshmead pupae, and other unidentifiable arthropod body parts. Daily activity coincided with environmental conditions of 100% relative humidity. Seasonal activity was quantified from hygrographic records. The distribution ofD. dormaniwas clumped. Population density was related to cultural practices and environmental factors. Control areas on citrus fruit not affected by the citrus tree snail were covered with microbiota. The ambulatory, nongrazed areas covered byDrymaeuswere encrusted with pedal secretions.Drymaeuspressed citrus rust mite spermatophores to the fruit surface and ruptured the sperm sacs, Mycelia were covered and encrusted with mucilage. Grazed areas, 1 cm wide, were void of microbiota and covered with a thin mucilage veil.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1091

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

The survival of a susceptible and two synthetic pyrethroid-resistant strains of the predatory mite,Amblyseius fallacisGarman, were compared with an indigenous predatory mite population after the applications of two synthetic pyrethroids, permethrin and fenvalerate. Susceptible and indigenous predatory mites were reduced to almost undetectable numbers after two permethrin and one fenvalerate application. The two resistant strains survived permethrin applications equally well, but only one strain survived the fenvalerate spray at measurable levels. Overwintering survival of resistant strains was confirmed by using microelectrophoresis and LC50, studies.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1096

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

An alfalfa aphid,Macrosiphum creeliiDavis (Homoptera: Aphididae), previously a noneconomic pest in the Pacific Northwest, became increasingly abundant beginning in 1963. Its host plant relationships were determined, as well as its developmental, survival, and reproductive rates on alfalfa in the laboratory. Anatomical differences were shown to distinguish it from the pea,Acyrthosiphum pisum(Harris), and potato,Macrosiphum euphorbiae(Thomas), aphids with which it might be confused. Its primary host plants were found to be alfalfa, lentils, Austrian pea, and broadbean. Most host plants of the pea and potato aphids were not acceptable.M. creeliireproduced well at temperatures as low as 5 to l0°C, and provided up to 70 progeny each. The only parasite found to attackM. creeliiwasAphidius pulcherBaker.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1100

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

The interspecific interactions of 5th-instarOrius insidiosus(Say) and 2nd-instar larvae of another mite predator,Leptothrips mali(Fitch), was studied in the laboratory.L. maliis a potential prey forO. insidiosus, but has a defensive anal secretion which repels predator attacks. Most contacts between well-fedO. insidiosusandL. maliresulted in mutual avoidance. Most attacks byO. insidiosuswere unsuccessful, especially if the approach was from the rear. Contact with the thrips' anal secretion resulted in immediate repelling ofO. insidiosus, with subsequent cleaning activity lasting 1 to 3 min. This study indicates that these two predators are compatible, especially in the presence of another food source such as the European red mite.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1104

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Male and female adultTenodera aridifolia sinensisSaussure (Orthoptera: Mantodea) were marked in an old field shortly after ecdysis. Mantid movement was ploned over a 17-day period. Males had a significant directional component to their movement, but the females did not. Males also moved significantly greater distances than the females over comparable periods of time.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1108

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Velvetbean caterpillar,Anticarsia gemmatalis(Hübner), larvae were reared on the following potentially important overwintering hosts in southern Florida:Dolichos lablabL. (hyacinth bean);Galactia speciformisTorr and Gray;Glycine max(L.) Merrill (soybean);Indigofera hirsutaL. (hairy indigo);Melilotus albaDesr. (sweet clover);Phaseolus lathyroidesL.;Phaseolus vulgarisL. (snap bean);Rhynchosia minima(L.) (least rhynchosia); and Vigna luteola (Jacq.). Development time, number of instars, pupal weights and foliage consumed were used to evaluate host suitability. Based on the first three categories,I. hirsuta,R. minima,P. lathyroides,V. lutoela,D. lablab, andM. albawere at least as good as soybean for larval development.P. vulagariswas the poorest host.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1112

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

The response of boll weevils,Anthonomus grandisgrandis Boheman (Coleoptera: Curculionidae), to trap density (number per ha) and grandlure concentration (wicks per trap) was determined in a noncotton area. Trap density in this area was not a factor in weevil capture. Traps with four wicks were significantly more effective than traps containing one or two wicks per trap. Results in a cotton field may differ, depending on competition between male weevils and traps and the maturity of the colton plants.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1114

出版商:Oxford University Press    

年代:1982

数据来源: OUP

摘要:

Six plots of pine trees harboring high densities ofN. sertiferlarvae were sprayed with the nucleopolyhedrosis virus (NPV) of this species. Half of these plots were resprayed in the second year of the study. Polyhedral inclusion bodies (PIB) were recovered in all plots from soil and foliage sampled at fixed time intervals within a 21-month period from the initial date of spraying. The concentration of PIB from both soil and foliage samples in the second year were generally lower in plots treated once than in those treated twice. NPV-induced larval mortality in plots sprayed once was 100% in the first season and 8% in the second. Laboratory bioassays of soil samples at intervals within the 21-month period resulted in 11 to 80% NPV-induced larval mortality. This study suggests that the NPV ofN. sertifercan persist and retain some activity for at least 21 months under field conditions.

ISSN:1754-5692    

DOI:10.1093/ee/11.5.1116

出版商:Oxford University Press    

年代:1982

数据来源: OUP