摘要:

Tests of the host specificity ofCoccipolipus epilachnaeSmiley, a mite parasitic on the Mexican bean beetle,Epilachna varivestisMulsant, suggested that hosts are limited to the members of the subfamily Epilachninae. Coccinellid species tested that were not suitable hosts included:Chilocorus stigmaSay,Coccinella septempunctataL.,Cycloneda munda(Say),Hippodamia parenthesis(Say),Hippodamia convergensGuérin-Ménèville,Coccinella undecimpunctataL. andCoccinella novemnotataHerbst.C. epilachnaedid complete its life cycle onSubcoccinella vigintiquatuorpunctata(L.), another epilachnine.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.46

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Nabis americoferusCarayon exhibited differential mortality when exposed to dimethoate, toxaphene-naled, and aldicarb in comparison to untreated plots.Dimethoate at 0.56 kg/ha cause significantly greater mortality to damsel bugs over a 7-day period than did a combination of 3.4 kg toxaphene and 2.2 kg naled/ha. The increased mortality caused by the dimethoate was reflected in the greater numbers of the beet armyworm larvae,Spodoptera exigua(Hübner), than in the plots treated with toxaphene-naled.In a 2nd trial,Nabismortality was recorded after 48- and 72-h exposure to cotton terminals following treatment. An untreated check, a single side-dressing of aldicarb, and 3 dimethoate applications were compared. Three dimethoate applications produced 3 predator mortality peaks. The untreated plots had the least mortality. Aldicarb produced moderate mortality which increased following each of two irrigations. The increase inNabismortality from check, to aldicarb, to dimethoate was reflected in proportional increases in late season larval populations of the cabbage looper,Trichoplusia ni(Hübner).

ISSN:1754-5692    

DOI:10.1093/ee/8.1.48

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

The minimum temperature threshold for the development of apple maggot pupae,Rhagoletis pomonellawas 6.4°C. From 1951–75 the 1st flies emerged in cages over infested apples on the avg on June 15 near Highland, NY and on June 23 in Geneva, NY. The avg accumulated air temperature thermal units (T.U.'s) from Mar. 1 using a threshold of 6.4°C until 1st emergence were 614±53 and 641±48, respectively, at the 2 locations. The annual deviations between the actual first emergence and the date when the avg T.U.'s were accumulated ranged from 1–8 days with an avg of 3.5 at Geneva and from 1–14 days with an avg of 5-7 days at Highland. From 1975–77 the mean T.U. accumulation and the 99% confidence interval developed at Geneva was used to predict emergence in 5 locations in Wayne Co. The deviations between the observed emergence and dates in which the appropriate number of T.U.'s was accumulated averaged 3.5 and 0.8 days, respectively.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.51

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Dauerlarvae of the insect-parasitic nematodeNeoaplectana carpocapsaewere either strongly attracted to or repelled by various concentrations of known constituents of insect feces. These included uric acid, xanthine, allantoin, ammonia, and arginine (attractants) and allantoic acid (repellent). Dauerlarvae exhibited aggregating behavior adjacent to paper treated with uric acid, suggesting that high concentrations were an arrestant. Certain combinations of uric acid, xanthine, allantoin, allantoic acid, and arginine greatly increased, decreased or masked the attractiveness of these chemicals.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.55

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Traps baited with slow release formulations of grandlure (30–40 mg/trap) remained effective for 6 wk without rebaiting and captured more boll weevils,Anthonomus grandis grandisBoheman, than traps rebaited weekly with 3 or 6 mg of grandlure. A 2-fold increase in grandlure concentration produced a significant increase in weevil capture, but captures were not increased additionally by a 4-fold increase when the 2 concentrations were not competing for capture of the same weevils.There was little difference in the attraction of boll weevils to one wick containing 3 mg of grandlure or to one laboratory reared male boll weevil that had fed on cotton squares.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.62

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

For 3 yr, blacklight traps were used to monitor the emergence of spring brood pecan nut casebearer moths,Acrobasis nuxvorellaNeunzig, at 7 locations in Louisiana. Moth activity varied from year to year at the same location and from location to location within the same year. Seasonal abundance varied greatly among locations with larger populations present in orchards along the Red River Valley compared to orchards in the Mississippi Delta and Ouachita Valley - Macon Ridge Area of the state.For 4 seasons, studies were conducted to assess the damage due to 1st generation pecan nut casebearer. At Monroe and Chopin, orchards characterized by little moth activity, casebearer damage was virtually non-existant; however, at Shreveport, where moth activity was the greatest, annual avg damage ranged from 10–28% infested nut clusters.As a result of these investigations, it appears that BL traps have the potential to be an effective tool in management of 1st generation pecan nut casebearer. Trap data were instrumental in a grower eliminating control applications for the pest the past 3 seasons. With further study, the traps may prove to be effective as a monitoring device to properly time insecticide applications in areas where casebearer continues to be an annual problem.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.65

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Traps that captured boll weevils,Anthonomus grandis grandisBoheman, alive were more effective than traps requiring an adhesive. A thixotropic adhesive was convenient to work with but did not weather satisfactorily. A trap that turns with a slight breeze did not capture more weevils than stationary traps. A latin square in time experimental design was effective in removing variation of mean weevil capture due to effects of season and trap location when trap designs were compared around a cotton field. A commercial trap based on the design of the Leggett trap was effective in capturing weevils. Pigmented adhesive sprayed on a cotton plant was ineffective in capturing boll weevils that responded to grandlure.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.70

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

The plant bugsLeptopterna ferrugata(Fallén) andMegaloceroea recticornis(Geoffrey) reduced seed set in grasses by feeding on the culm or directly on developing seeds. Bugs made relatively fewer feeding probes on stems than on leaves and panicles during different stages of development of grass. The viability of seeds was destroyed when bugs had fed directly on the developing seeds. Survival of overwintering eggs laid in the stems of grasses determined the density of bugs the following season and was influenced by postharvest management of the straw. Mechanical removal of the straw was not as effective in reducing the incidence of feeding injury as burning the straw.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.73

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Seven plots in Monroe CO., Pa., with a general gypsy moth,Lymantria dispar(L.), infestation were treated with disparlure. A total of 2957 egg masses was examined for numbers of eggs, parasitism byOoencyrtus kuwanai(Howard), and embryonation. The application of disparlure had no effect on either size of egg mass or percent parasitism. There was also no effect due to the height on the tree from which the egg mass was collected. However, an interaction between height and egg mass size did affect parasitism within 0.25 m of the ground. The greatest variability in the data was attributed to plot differences. This was related to the selection of plots on the basis of level of gypsy moth infestation, and the resultant differences in egg mass size. The negative dependence of percent parasitism on number of eggs per egg mass was linearized with a natural log transformation of eggs per mass. The regression model accounted for 75% of the variation in the data. The overall weighted avg percent egg parasitism was 49.8, with a range of 26.9–81.6.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.77

出版商:Oxford University Press    

年代:1979

数据来源: OUP

摘要:

Egg production rates were obtained, under controlled laboratory conditions, forChrysopa carneafemales collected from alfalfa field plots, where the adults had fed on either naturally-occurring foods or various artificial food sprays. These field collected adults then were fed only a sucrose solution in the laboratory.Females field-fed a nutritionally complete food spray responded by producing eggs at a higher rate than those feeding on sugar alone and at comparable rates with those feeding on naturally-occurring foods, i.e., honeydew and/or pollen.The intensity of attraction and egg production ofC. carneato artificial food sprays was found to be greatly modified by seasonal changes in the quality and quantity of naturally-occurring foods and the numbers of resident adults in the vicinity of the food sprays.

ISSN:1754-5692    

DOI:10.1093/ee/8.1.81

出版商:Oxford University Press    

年代:1979

数据来源: OUP