摘要:

The half-life of unpasteurized and pasteurized dried films ofBacillus thuringiensisexposed to a laboratory UV source was 30 and 45 min, respectively. Films ofB. thuringiensiscontaining peroxidase and exposed to UV were significantly more stable than those not containing peroxidase. The findings supported the assumption that sunlight inactivation of entomopathogens probably is caused by peroxide or peroxide radicals produced by the UV irradiation of amino acid (s).

ISSN:0046-225X    

DOI:10.1093/ee/7.2.270

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

Experimentally determined cold tolerances of eggs, larvae, and pupae of the stable fly,Stomoxys calcitrans(L.), exposed to constant cold temperatures are reported. These data were used to develop predictive models for relating mortality of these immature stages of the fly to cold exposure levels defined by different combinations of exposure times and temperatures.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.273

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

Males of the Nantucket pine tip moth,Rhyacionia frustrana, flew significantly earlier on cool than on warm nights in response to traps baited with either crude pheromone extract or live females. Moths were unable to sustain flight below 10°C. Initiation of flight appeared to be unrelated to light intensity.The early flight on cool nights increases the probability that sufficient numbers of the moths emerging from overwintering pupae will successfully mate and maintainR. frustranapopulations.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.278

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

The seasonal dynamics of house dust mites,Dermatophagoidesspp., was investigated for 19 mo in southern Calif. In Orange Co. houses sampled,D. pteronyssinus(Trouessart) was generally more abundant from July–Nov. or Dec., whileD. farinaeHughes was more prevalent from Aug.–Dec. or early spring. Both species were less abundant from late spring to ca. July. In Riverside houses, both species were generally more abundant from late summer to early fall (1975), and from early spring to early summer (1976), with lower numbers present from June–July (both years). Monthly fluctuations of each species generally corresponded to climatic changes, particularly RH, with increased populations occurring 1–2 mo after conditions approached or became optimum forD. farinaeorD. pteronyssinus, while populations declined when RH reached or fell below critical levels for the respective species.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.281

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

Two strains of the two-spotted spider mite,Tetranychus urticae, were 20–40 times more tolerant to permethrin than 3 strains of the phytoseiidMetaseiulus occidentalis. One predator colony was 2 times more susceptible to permethrin than the other two. The authors note that very low rates of permethrin might preserveM. occidentalispopulations in the field.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.287

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

A survey for hymenopteran parasites of the eggs ofPeriplaneta americanaL.,P. brunneaBurmeister,P. fuliginosa(Serville), andBlatta orientalisL. conducted in 17 Texas and 4 Louisiana cities during 1974–75 revealed the existence of 2 primary parasites,Tetrastichus hagenowii(Ratzeburg) andEvania appendigaster(L.). Parasitization rates at the survey sites ranged from 0–68% ($\tt\ \bar x$= 26%).T. hagenowiiwas found at the majority of the Texas and all of the Louisiana sites and accounted for 99.4% of the total parasitism. Only 4 specimens ofE. appendigasterwere recovered fromP. americanaoothecae collected from 2 Texas localities.T. hagenowiiparasitized oothecae deposited at heights up to 3 m in either concealed or unconcealed locations.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.289

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

The establishment since 1974 of colonies ofColeophora parthenicaMeyrick on Russian thistle,Salsola ibericaSennen and Pau, at 4 locations in southern California is reported. This stem and branch borer was successfully introduced from Pakistan. The larvae and pupae are parasitized in California by the solitary, external parasite,Norbanus perplexus(Ashmead) (Hym.:Pteromalidae). At current levels of establishment no control of Russian thistle has been observed.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.294

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

The rates of development of larvae and pupae of the waxmoth,Galleria mellonella, and its nuclear polyhedrosis virus (Baculovirus) were determined over a range of temperature from 18°–40°C. Larvae did not undergo significant development at 18°C and virus disease was slowed but not inhibited. At 40°C, both larval development and virus disease were stopped. Upon return to a lower temperature, larvae resumed development but the degree of disease development depended upon the time of exposure to the high temperature.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.297

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

A study was conducted to determine the oviposition preferences of certain permanent and floodwater mosquitoes relative to selected Louisiana marsh plants.Culex salinariusCoquillett showed a significant (P<0.01) preference forDistichlis spicata(L) Greene habitats in both the intermediate and brackish marsh impoundments (2.07 and 1.15 larvae/dip, respectively).Anopheles bradleyiKing was collected in association withSpartina patens(Ait) Buhl. habitats in significantly (P<0.01) higher numbers (0.12 from the intermediate and 0.21 larvae/dip from the brackish marsh impoundment) than in association with other plant species.Culiseta inornata(Williston) was collected only in the intermediate marsh impoundment in association withD. spicata(0.13 larvae/dip).Soil samples fromD. spicatahabitats contained significantly (P<0.01) moreAedes sollicitans(Walker) eggs thanS. patensorBacopa monnieri(L) Wettst., yielding 52% of the eggs collected.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.300

出版商:Oxford University Press    

年代:1978

数据来源: OUP

摘要:

Haplaxius crudusnymphs feed and live in the thatch layer and on the roots of St. Augustinegrass, bahiagrass, centipedegrass, bermudagrass, paragrass, yellow nutsedge, broomsedge, foxtail, and other sedges. Secretions from the abdominal wax glands protect the nymphs from wetness, disease, and predators. Average nymph size after each molt at 24°C was 0.80, 1.35, 1.80, and 2.47 mm for 4 respective molts. No differences in size were noted at 30°C. Wingpad development between each molt is a unique characteristic for identifying nymphal age. All nymphal instars developed more rapidly at 30° than at 24°C. Cool temperature (15°C) had an adverse effect on nymph development. Large nymphs survived an extended period without feeding. Eggs were 0.5–0.6 mm in length and 0.15–0.20 mm in width with one blunt end. Parthenogenic reproduction was not observed. The mean life span for adult males on St. Augustinegrass was 7.3 days and 7.8 days for adult females. The mean generation time at 30°C was 52.6 days and 80.8 days at 24°C. The adultH. crudussurvived 37 and 50 days on coconut and veitchia palms, respectively. Coconut cultivars differed significantly in numbers ofH. crudusattracted. The numbers of adults attracted to palm differed significantly among seasons.H. cruduswas found in palms more in the evening hours than in the morning hours.

ISSN:0046-225X    

DOI:10.1093/ee/7.2.305

出版商:Oxford University Press    

年代:1978

数据来源: OUP