摘要:

The solitary egg parasitoidTelenomus heliothidisAshmead recognized its host, the eggs ofHeliothis virescens(F.), (Lepidoptera: Noctuidae), by both chemical and physical cues.T. heliothidisonly accepted hosts between 0.50 and 0.63 mm in diameter, with spherical hosts preferred to spheroidal hosts. Color was not a critical factor in host recognition byT. heliothidis. A minimal area of the host had to be coated by a recognition kairomone to be accepted even if the host were properly shaped. Recognition of both host shape and odor appeared to be by the antennae.T. heliothidisshowed a preference for younger host eggs. This preference was attributed to the change in shape of olderH. virescenseggs.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1114

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

A generalized life cycle and biology of the morphs are described forBrachycolus asparagiMordvilko. Oviparae laid overwintering eggs on the asparagus ferns,Asparagus officinalisL., beginning in September. The eggs hatched in late March and developed into fundatrices that established themselves on the emerging asparagus spears. A fundatrix gives birth to about 18 nymphs, as compared with 54 nymphs for an apterous virginopara. In summer, the apterous morph had a 33.5% higher intrinsic rate of increase than the alate morph. Crowding of nymphal asparagus aphids increased wing production. The fecundity curve for the apterous virginoparae peaked once, early in their reproductive phase, whereas the curve for the alate virginoparae peaked a number of times and showed that their reproductive phase spanned most of their adult life. A single sexupara could give birth to oviparae, as well as to male and virginoparous morphs. The oviparae produced an average of 10.5 eggs. Males were capable of multiple matings.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1120

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

Only about 1% ofBathyplectes anurus(Thomson) females, from five locations in three states, had nonfunctional ovaries. In contrast, the ovaries of nearly 10% ofB. curculionisfemales from four states were infertile. This infertility was related to time of emergence from the cocoon; females emerging during the first half of the emergence period had normal ovaries, but 23% of late-emerging females had nonfunctioning ovaries. Ovaries of both species reached maximum fertility (presence of eggs in oviducts) within 24 h of eclosion. Cocoons that had previously been candled, to eliminate dead individuals, had eventual survival rates of from 54% (B. curculionis) to 68% (B. anurus). The proportion of females produced was 49% forB. anurusand 63% forB. curculionis. The reduced ovarian function ofB. curculionisis one of the likely reasons thatB. anurushas become the dominant parasite of alfalfa weevil larvae in the New Jersey-southeastern Pennsylvania area during the past decade.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1125

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

Alfalfa weevil embryo and larval establishment mortalities were assessed as a function of embryonic age (aged 10, 25, 50, 75, and 100 degree-days Celsius) when development was interrupted, duration of the interruption (up to 60 days), and temperature at which development was interrupted (4, − 6, − 16°C). Based on the sequence of treatment combinations that significantly influenced mortality, it was concluded that the more advanced the embryonic age when development was interrupted, the longer the interruption, and the lower the temperature during the interruption, the greater the embryo mortality (EM), larval establishment mortality (LEM), and therefore the total mortality (TM) (TM = EM + LEM).

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1129

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

Oviposition patterns ofHeliothis zea,Manducaspp.,Spodoptera exigua, andTrichoplusia niwere studied in processing-tomato fields of northern California. The initiation of egg laying appears to be related to flower formation, with peak egg deposition occurring in relation to the peak number of open flowers per plant forH. zea, S. exigua, andT. ni. Oviposition byManducaspp. increases as the season progresses. All species deposit most of their eggs on leaves of the terminal half of the branch. The majority of eggs are located on the ventral leaf surface, within one leaf of the inflorescence. From these data, it is possible to estimate the number of plants that would have to be sampled to find an egg of one species at a given egg density.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1133

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

Temperature-dependent simulation models for nondiapause and postdiapause development of alfalfa blotch leafminer pupae,Agromyza frontella(Rondani), were used to analyze the late summer and fall development of pupae under field and laboratory conditions. Pupal development during the second summer generation was accurately simulated by the nondiapause model under both laboratory and field temperature conditions. Adult emergence in the field during the fall generation was overestimated by the nondiapause model used in conjunction with recorded field soil temperatures. This suggested that diapause occurred in the fall generation, although prolonged pupal development was not readily observed in the laboratory. The development of fall generation pupae collected from the field in October and November and reared under controlled temperatures was adequately simulated by the postdiapause model but not the nondiapause model. The results suggest that a fall generation pupal diapause occurs and is largely completed by November.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1138

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

The host suitability ofForcipata locaDelong and Caldwell was determined in a series of feeding and oviposition tests conducted in the laboratory and field. The plants tested included forage and weed species commonly found in Missouri pastures. Visual examination of plants, radioisotope labeling, and adult survival and oviposition were techniques used to determine host suitability. Twentyone test plants were acceptable food hosts, and 12 also were acceptable breeding hosts. The majority of plants belonged to the family Gramineae, and three belonged to the closely related family Cyperaceae.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1149

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

In central and eastern Iowa, adults of the European corn borer (ECB),Ostrinia nubilalis(Hübner), were captured hourly with blacklight traps (BLT) in and away from action sites (dense vegetation where ECB adults mate and rest) for 14 nights during the second flights of 1980 and 1981. Also, samples of moths in the grass at the action sites were taken hourly. Peak capture of females in the BLT occurred immediately after dusk, whereas peak male capture occurred during the period of greatest mating activity (ca. 2400 to 0100 h). Captures of males remained much greater than those of females throughout the rest of the night, indicating that, during this period, males are captured while seeking less mobile females. This difference in mobility explains the tendency of males to outnumber females in BLT. Males tended to outnumber females in captures obtained daily in action sites with a drop-net. The drop-net data suggest that, after oviposition in cornfields, not all mated females return to the action site each night, but that males usually remain in the action sites because of the pheromone released by the unmated females.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1154

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

Experiments were conducted to evaluate the response of 3rd-instar larvae of the horn fly,Haematobia irritans(L.), to laboratory-simulated bovine manure pat temperature gradients. Significant differences were found to exist between distributions of larvae in pats with uniform and gradational temperature profiles. Larvae exhibited a positive thermotaxis toward warmer, but nonlethal, temperatures in the upper strata of the pat from 0800 to 1000 h; however, between 1400 and 1800 h, a negative thermotactic response to potentially lethal temperatures occurred as larvae were recovered primarily from the comparatively cooler, lower strata of the pat.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1159

出版商:Oxford University Press    

年代:1983

数据来源: OUP

摘要:

The production of extrafloral nectar by cotton had two distinct peaks with cultivar ‘Stoneville 7A,’ the first peak produced by mainstem node leaf nectaries and the second peak produced by subbracteal nectaries on fruiting structures. Cultivar ‘Coker 201’ produced a first peak corresponding with that observed for ‘Stoneville 7A,’ and a much less pronounced but corresponding second peak. Oviposition byHeliothis punctigeraWallengren moths was highly correlated with extrafloral nectar production during the first 13 weeks of the crop's development but poorly correlated later in the plant's development. It is postulated that the low correlation late season may be due to any of several factors, including a change in nectar quality or buildup of fungi associated with the nectaries.

ISSN:0046-225X    

DOI:10.1093/ee/12.4.1166

出版商:Oxford University Press    

年代:1983

数据来源: OUP