摘要:

Resistance to defoliation of lodgepole pine,Pinus contortaDouglas, byColeotechnitessp. was investigated during an outbreak in central Oregon in the late 1960's. Severity of defoliation was closely associated with forest-site characteristics, tree age, and location of foliage in the tree crown. Through field-caging studies and laboratory-preference tests it was established that larvae invade some types of foliage more readily than others. Variation in susceptibility of foliage to attack was related to patterns of defoliation in the outbreak. It was concluded that degree of resistance to attack was probably determined by a feeding deterrent in the foliage which varied according to site, tree, and location in the crown.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.947

出版商:Oxford University Press    

年代:1973

数据来源: OUP

ISSN:0046-225X    

DOI:10.1093/ee/2.5.949

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

A method is described for estimating population sizes of arthropods inhabiting the soil surface, using pitfall trapping procedures. The problem of migrations was circumvented by using aluminum foil strips, coated with resin, as barriers around plots. Estimates of populations of Diplopoda, Araneida, Orthoptera, and Coleoptera made with the pitfall technique showed good agreement with estimates based on sorting by hand.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.951

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

Dark enamel spheres about the size of a large apple are highly attractive to apple maggot flies,Rhagoletis pomonella(Walsh) (Oatman 1964a; Prokopy 1967, 1968a, b; Moore 1969; Kring 1970; Rivard 1972). Also, yellow enamel rectangles are highly attractive to these flies (Still 1960; Oatman 1964b; Howitt and Connor 1965; Wilde and Goble 1966; Prokopy 1967, 1968b, 1972; Maxwell 1968; Moore 1969; Kring 1970). My recent study (Prokopy 1972) showed that rectangles painted daylight fluorescent yellow attract even more flies than those painted with yellow enamel. This is a report on the orchard response of apple maggot flies to spheres coated with various colors of daylight fluorescent paint or covered with aluminum foil compared with dark enamel spheres.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.953

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

Subterranean termites are among the most abundant but cryptic of animals, a factor making behavioral studies very difficult. Consequently little is known of their foraging behavior or general activity patterns. Previous studies have been restricted mainly to mound builders (Bouillon and Lekie 1964) or harvesters which forageopenly on the soil surface (Bouillon 1970, Nel 1968). A few estimates of subterranean termite populations have been based on baiting with attractive materials or soilcore sampling (Sands 1972).

ISSN:0046-225X    

DOI:10.1093/ee/2.5.954

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

Although Eurasian gypsy moth,Porthetria dispar(L.), females are known to fly (Mikkola 1971) the premise that the females of the European form are flightless has been widely accepted. Since the European form was introduced into North America in 1869, many studies have been made of various aspects of its life history. The descriptions usually state that the adult female does not fly (e.g., Beroza and Knipling 1972, Campbe11 1967, Friend 1945). This statement may be a perpetuation of the report that “The female has never been seen to fly in this country, except on one occasion, and that was after the laying of the eggs.” A female “that had finished or nearly finished laying her eggs, upon being disturbed by males, drop[ped] to the ground and … [flew]about twenty feet, striking the ground and rising again at distances of about two feet” (Forbush and Fernald 1896). Most entomologists either ignore or discount the single report of flight, and state categorically that females do not fly.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.957

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

Biological control of economically important insect pests of crop plants has a long history (Clausen 1956) during which releases of insect parasites have played a dominant role. The method has been particularly used in attempts to control such alfalfa insect pests as the alfalfa weevil,Hypera postica(Gyllenhal) (Brunson and Coles 1968), the Egyptian alfalfa weevil,H. brunneipennisBoheman (Clancy 1969), and the spotted alfalfa aphid,Therioaphis maculata(Buckton) (Van den Bosch et al. 1959). However, in all such work, the parasites were released in relatively small numbers, and control was not anticipated until after a sufficient period of natural buildup. Thus when Knipling (1966) suggested inundation of insect populations by mass production and sustained release of parasites and predators as a means of suppressing insect populations, Ridgway and Jones (1969) attempted to control the bollworm,Heliothis zea(Boddie), and the tobacco budworm,H. virescens(F.), on cotton by making inundative releases of eggs of a lacewing,Chrysopa carneaStephens. Knipling and McGuire (1968) indicated the importance of the plant-growth factor on limiting the efficiency ofTrichogramma. Fye and Larson (1969) made preliminary evaluations ofT. minutumRiley as a released regulator of lepidopteran pests of cotton, and Surber (1970)3subsequently pointed out that these releases ofTrichogrammasp. on cotton were apparently ineffective, because the 10,000 wasps/ week that were released could not completely search the area of the host plant which had increased 7.6–fold in 8 weeks. The increase in leaf area may therefore be an important consideration in use of inundative releases of insects for immediate control of harmful insect populations. Also, this increase is important in determining optimum rates of insecticides to insure maximum control of the target insect while minimizing costs, effect on nontarget species, residues, and environmental pollution. We therefore investigated the possibility of producing accurate estimates of the daily increase in the area of alfalfa leaves in relation to temperature in southern Arizona.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.958

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

Few methods have been described for marking tabanids. Bennett and Smith (1968) marked them with32p in water which the flies imbibed. Thornhill et al. (1971), and Thornhill and Hays (1972) marked flies with model airplane dope. Face flies,Musca autumnalisDe Geer, were marked successfully with fluorescent powder for field studies (Turner and Gerhardt 1965). In studying tabanid flight in Louisiana we wanted to mark large numbers of flies with a minimum of interference. We allowed the flies to mark themselves with Day-Glo fluorescent pigments3as they passed through a selfmarking device mounted on a canopy trap (Catts 1970), as modified by Adkins et al. (1972).

ISSN:0046-225X    

DOI:10.1093/ee/2.5.960

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

A colton-pest management program covering 40,000 acres in 1700 fields was initiated in 2 locations in Georgia in 1972. A major component of the program was use of cotton-insect “scouts” who made weekly surveys of each field to determine population levels (for beneficial and pest species) and existing damage.OP insecticides are relied upon heavily for cottoninsect control in Georgia. Insect resistance to chlorinated hydrocarbons has resulted in greater usage of OP insecticides. However, because of their relatively greater toxicity and because they are readily absorbed through the skin, it is not surprising that most deaths from pesticides have resulted from use of OP chemicals (Davies et al. 1967). A more widespread use on cotton is inevitable with the ban of DDT. Because of the significant role played by organophosphates in acute intoxications and the enthusiasm for them in pest-management programs, the Georgia Cooperative Extension Service monitored the health of the program personnel throughout the summer.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.961

出版商:Oxford University Press    

年代:1973

数据来源: OUP

摘要:

The black cutworm,Agrotis ipsilon(Hufnagel), is sometimes a highly destructive pest of a large number of seedling crops (e. g., clover, soybeans, tobacco)throughout the United States. The factors contributing to these occasional economically important infestations are not entirely understood, especially in the Midwest. In Tennessee, Crumb (1929), in the Central Great Plains, Walkden (1950), and in Wisconsin, Apple (1967) concluded thatA. ipsilonoverwinters in the pupal stage, since they could not carry the larval stage through the winter. Other workers apparently assumed that infestations in cultivated crops arose from springemerging adults, though Davidson and Peairs (1966) did indicate overwintering in the insect's larval stage. However, they did not specify any geographical area, and they may have had reference to subtropical areas where infestations are known to occur during the winter (Oatman and Platner 1972). In the present paper we present evidence that infestations ofA. ipsilonin the Midwest result from overwintering larvae. Our evidence is based primarily on the parasitic relationship between the mermithid nematode,Hexamermis arvalisPoinar and Gyrisco, andA. ipsilon, as well as between other parasites of the pest.

ISSN:0046-225X    

DOI:10.1093/ee/2.5.963

出版商:Oxford University Press    

年代:1973

数据来源: OUP