摘要:

When 18,416 adultScolytus multistriatuswere marked with a fluorescent powder and released, 27% were recaptured in pheromone-baited traps. Of these, 98% were captured on traps 1.5 m from the release point, but the maximum distance for capture was 160 m. In another phase of the study, adult beetles were marked with32P as they emerged from elm logs. Of 1964 beetles subsequently captured in pheromone-baited traps, 63% were 1.5 m from the emergence site. EndemicS. multistriatusfrom unknown sources were caught in all traps, with an avg of 2553/trap and a total of 51,059. They were found at all trap heights to 4.8 m.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.1

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

An olfactometer designed forOryctes rhinoceros(L.) is described and its effectiveness demonstrated by a comparison of results with field tested chemicals. Using the olfactometer, (±)-Des-N-morphinan, but not its stereoisomer was found to be a strong attractant for adult rhinoceros beetles. This is the 1st synthetic bridged hydrocarbon found to be an insect attractant.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.6

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Significantly more leafhoppers, especiallyAmbylsellus curtisii(Fitch),Doratura stylata(Boheman),Draeculacephala antica(Walker),Graminella nigrifrons(Forbes),Endria inimica(Say), andMacrosteles fascifrons(Stål), were collected from nitrogen fertilized (480 kg N/ha) than from unfertilized plots of 3 grass cultivars out of 39 in 1971 and 9 out of 23 N-fertilized (240kg N/ha) cultivars in 1972. Also, more grasshoppers,Dicromorpha viridisScudder,Melanoplus bivittatus(Say), and anotherMelanoplusspecies; the flea beetles,Chaetocnema pulicariaMelsheimer andSystena frontalis(F.); and the frit fly,Oscinella frit(L.), were collected in significantly higher numbers on some N-fertilized cultivars.Peak numbers of most insect species occurred in late summer. Carbofuran (10% granules, 2.24 kg AI/ha in 1972) and (flowable, 1.12 kg AI/ha in 1973) reduced mean numbers of most species of insects and resulted in increased dry matter yield of a few cultivars both years.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.11

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Studies of the locust twig borer,Ecdytolopha insiticiana(Zell.), were conducted in 2 geographic regions of Maryland which differed sizeably in elevation and length of growing season. The number of larval instars was established. Head capsule dimensions were statistically analyzed and grouped into 7 separable categories, representing 7 probable larval instars. Compared within instars, the larvae mined greater distances upward from the point of attack than downward. Distances of attacks from the tip of the tree stem were significantly greater with advanced larval instars. Larvae per burrow averaged 1.41 for the entire study and numbers per burrow were not significantly different for different instars.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.19

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Sampling of a grasshopper (Acrididae) population weekly during the summer months of 1975, 1976, and 1977 showed that hatching began when the soil temperature (one cm below the surface) was above 15.6°C for a total of at least 200 h and when the degree hours (number of degrees each hour that the soil temperature exceeded 15.6°C) totaled 2466. Grasshopper density decreased from 1975–77. In 1975Melanoplus sanguinipes(F.) totaled 53% of the number collected; in 1976 and 1977,Amphitornus coloradus(Thomas) was most abundant and comprised 23% and 30%, respectively, of the population. Grasshoppers became active at surface temperatures (5 cm above ground) of 13°–16°C, and feeding began at 21°C. Three-yr averages showed the surface temperatures remained above 21°C for 12 h each day in July, 10 h in August, and 8 h in Sept. Seasonal growth, including seed set, of 3 grass species (western wheatgrass—needleandthread—prairie junegrass) was mostly completed before grasshoppers developed to the damaging stage (4th and 5th instars and adults). Clipping studies showed that grass and forb production decreased from 1473 kg/ha in 1975 to 503 kg/ha in 1977 and was directly correlated with spring and summer precipitation. Forage lost to grasshoppers was estimated at 235 kg/ha in 1975, 226 kg/ha in 1976, and none in 1977.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.24

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Spider prey of 2 mud dauber wasps,Sceliphron caementarium(Drury) andChalybion californicum(Saussure), was determined in Comanche Co. Oklahoma. Of 747 spiders removed from mud nest constructed bySceliphron, 93% were either araneids or thomisids. Examination of 446 spiders from nests utilized byChalybionshowed 99.3% of them to be either araneids or theridiids.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.30

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Seasonal flight activity of peachtree borer,Synanthedon exitiosa(Say), males was monitored from 1975–77 in the Georgia peach belt (Peach, Houston, and Crawford Co.) by recording captures in sticky traps baited with a synthetic sex pheromone. Male moth flight began in late Apr., peaked in late Aug. or early Sept. and ended the last week of Oct. Emergence trapping patterns were essentially the same for different environmental locations sampled, regardless of the pheromone concentration used, except that seasonal flight was shorter in the piedmont area. Pheromone trap monitoring appears to be adequate for detecting infestations and characterizing seasonal flight activity.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.32

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Water velocity, substrate placement and the length of exposure time influenced the number ofProsimulium mixtum/fuscumSyme and Davies andCnephia dacotensisDyar and Shannon larvae attaching to white ceramic tiles and clear plastic tapes in the field.P. mixtum/fuscumreadily attached to either substrate whereasC. dacotensisdemonstrated a preference for white ceramic tiles. In an artificial stream, both species preferred specific velocity ranges although they did not increase their relocation behavior when exposed to varying depths of 2 to 30 cm and temperatures of 2° to 30°C.P. mixtum/fuscumincreased relocation behavior in the absence of light.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.34

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

The aggregation pheromone ofDendroctonus jeffreyiwas investigated by combined gas chromatography and mass spectrometry of volatiles from hindguts of attacking beetles. The major compounds in females were identified as 1-heptanol and 2-heptanol, which are produced by oxidation of heptane present in the host resin. In field tests, 1-heptanol in combination with heptane was attractive, but racemic 2-heptanol was not. The addition of 2-heptanol to 1-heptanol appeared to reduce the number of beetles responding.The results indicate a probable difference between the chemical communication systems ofD. jeffreyiandD. ponderosae, both of which have apparently adapted to utilize the metabolic products of potentially toxic hydrocarbons in their hosts.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.40

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Bollworm,Heliothis zea(Boddie), seasonal abundance in corn and sorghum was determined using 40-w blacklight (BL) traps and field sampling. Comparison of bollworm moth catches and egg numbers indicated that the number of eggs during periods of peak oviposition is more closely related to the number of males than to the number of females caught in the BL traps.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.42

出版商:Oxford University Press    

年代:1979

数据来源: OUP