摘要:

The concept of computer maps as a data management and resource optimization technique in pest management is presented. A specific example is the use of the widely available computer mapping program SYMAP in the pest management program for the cereal leaf beetle,Oulema melanopus(L.).

ISSN:0046-225X    

DOI:10.1093/ee/4.3.357

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

A program of mass-trapping for control of 6 tortricid pest species of apple demonstrated relationships between trap catch and an index of apple foliage volume.Analysis of the trap catch data obtained from trap station densities ranging from 4 to 17 stations/acre revealed significant correlations between number of male moths caught and the amount of foliage/acre forArgyrotaenia velutinana(Walker),Choristoneura rosaceana(Harris),Grapholitha molesta(Busck), andGrapholitha prunivora(Walsh). The correlation was not significant forPandemis limitata(Robinson). Where the trap catch of the tortricids did not correlate significantly with foliage volume, the correlation between catch and trap density suggested that pheromone trap efficacy was decreased by a lack of effective drawing range, density of the foliage, competition by calling females, or some interaction of these factors. In the case ofLaspeyresia pomonella(L.), which was established in a gradient across the orchard, significant correlations between population density, foliage volume, and trap density were not evident.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.361

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

The effect of wheat trichome length was distinguished from the effect of density of trichomes by determining the oviposition and larval survival ofOulema melanopus(L.) on 9 wheat lines. The 3 densities and 3 lengths of the trichomes quantified 6 profiles that were defined as few-very-short, few-short, very-many-short, few-long, many-long, and very-many-long. Eggs per plant and percentage larval survival decreased in the same order. Trichome length is therefore an important resistance factor.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.365

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

Mortality of pre-adultRhinocyllus conicusFroelich on musk thistle (Carduus nutansL.) at Pulaski, Va., in 1972 was 68.0%. The range in mortality at 11 sampling sites was 56.6–95.8%; greater losses occurred in open, unsheltered pasture. Egg and early instar larval mortality (58.3%) resulted primarily from egg destruction by wind and rain. Mortality of late instar larvae and pupae (9.7%) was partially attributable to parasitism (3.6%) byAliolus curculionis(Fitch),Bracon mellitor(Say), andCampoplex polychrosidisViereck. Some loss of larvae and pupae was caused by crowding.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.371

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

The distribution of 6 species of false wireworms within 3 major soil textural classes (clay, loam, and sand) was studied in South Dakota.Eleodes hispilabris(Say) andEmbaphion muricatum(Say) were more prevalent in areas of loam and sand, whereasEleodes suturalis(Say) andEleodes obsoletawere more common in sandy areas.Eleodes tricostata(Say) was evenly distributed among the 3 soil classes.Eleodes opaca(Say) was equally prevalent in clay and sand soils. Although damaging populations of false wireworms were reported to have previously occurred in light sandy soils, recent outbreaks in South Dakota have occurred in regions of heavier soils. This study provides an indication of what species could be expected to cause damage in the major soil areas.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.373

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

A refined sampling technique showed that eggs ofCerotoma trifurcata(Forster) did not occur more than 3.8 cm below the soil surface. Of the eggs found within a 5.1-cm radius of plants more or less isolated in the row, almost 77% were within 2.5 cm of a plant. Thus, a cylindrical sample 5.1 cm in diam, 3.8 cm deep, and centered on a plant or a clump of plants is sufficient for determining relative numbers of eggs. Such small samples greatly accelerate the procedure for extracting eggs from the soil samples. Series of contiguous cubical samples, running perpendicularly across a row and halfway to the adjacent row in either direction, showed that over 73% of the eggs were within 2.5 cm of a row of plants and over 92% within 7.6 cm. Our findings provide the basis for developing a sampling technique for determining absolute numbers of eggs per area of crop field. Minor modifications of the extraction procedure are also described.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.375

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

Larvae of the cabbage looper,Trichoplusia ni(Hübner), parasitized byCopidosoma truncatellum(Dalman) consumed 35% more food and had a 30% higher maximum weight than unparasitized larvae. Food consumption and larval weight gain were exponential in both parasitized and unparasitized larvae, and parasitized larvae were more efficient in the conversion of ingested food into body weight. The greater consumption by parasitized larvae may affect plans for integrated biological control involvingC. truncatellum.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.381

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

Laboratory and field strains ofMuscidifurax raptorGirault and Sanders and a laboratory strain ofSpalangia endiusWalker were tested in environmental chambers. The field culture ofM. raptorwas obtained by exposing pupal house flies,Musca domesticaL., to a natural population of parasites.Parasitism of house fly pupae was less successful at either of the lower temperature conditions (spring/fall or winter). At summer conditions, the field culture ofM. raptoremerged over a slightly longer period than did the laboratory culture, though emergence began at about the same time. At spring/fall conditions, the field culture took somewhat less time to develop than the laboratory culture; at winter conditions, it developed much faster than the laboratory culture.Spalangia endiustook somewhat longer for development at all temperatures.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.383

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

Mortality factors and other life table data are presented forLaspeyresia pomonella(L.). Fecundity for the summer broods is ca. 50 eggs per female, with the spring brood females producing 25–30 each. Egg mortality ranges from 25% under caged conditions up to 50% under natural conditions. First-instar mortality is ca. 65%; and larval stages in apples suffer 35% mortality. The rate of mortality to 5th instars depends on the predators and parasites present, but a conservative estimate of 5th-instar mortality is ca. 30% in an unsprayed orchard. Pupal mortality is insignificant. Mortality to the overwintering larvae ranges from 50–75%, depending on what predators and parasites are present. These data should provide information necessary to develop an accurate simulation model of codling moth population dynamics.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.385

出版商:Oxford University Press    

年代:1975

数据来源: OUP

摘要:

HatchingPorthetria dispar(L.) larvae acquire nuclear polyhedrosis virus from the egg surface or from contaminated hair as they emerge from the egg mass. In comparative tests hair appeared to be more infectious than eggs. The most heavily contaminated material was debris taken from sites used for larval shelter and pupation. One hundred percent mortality occurred in hatching larvae exposed to the composite of exuviae, larval and pupal cadavers, and empty pupal cases. Debris mats are characteristic of dense but not sparse gypsy moth populations.

ISSN:0046-225X    

DOI:10.1093/ee/4.3.392

出版商:Oxford University Press    

年代:1975

数据来源: OUP