摘要:

ABSTRACT.FemaleLucilia sericataMg. fed a reproductive diet of meat were sterilized by injection of 10μg of tepa. Light microscopy revealed that the medial neurosecretory cells of the brain of sterilized flies were highly active compared with the same cells in untreated flies of similar age and nutritional status. The corpora allata of sterilized flies were also greatly enlarged. The evidence suggests that developing oocytes secrete a substance that inhibits the corpora allata hormone, thereby suppressing brain neurosecretory cell activity and preventing oogenesis in the subsequent oocytes

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00326.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.In an ambient temperature (Ta) range of 18–28°C, thoracic temperatures (Tth) of individual maleLymantria dispar(L.), caught at flight in the field, ranged from 21 to 36.5°C, with a correlation coefficient of 0.63 betweenTthand ambient temperature (Ta). Ambient temperature (and insolation) altered the insect's body temperature and the probabilities, latencies, and durations of preflight responses to pheromone. In a wind tunnel at 16 and 20°C, quiescent males exposed to pheromone raised theirTthby sustained wing fanning from 17 and 21°C, respectively, toc.24°C before takeoff. At 24 and 28°C ambient,Tthrose by takeoff to 28 and 31°C, respectively. The latencies of male wing fanning in response to pheromone decreased from 1.44 min at 16°C ambient, to 0.58 min at 20°C, to 0.26 min at 24°C, and to 0.16min at 28°C. The components of behaviour (antennal twitch, body jerk, step and wing tremor) that occurred between quiescence and wing fanning were more frequent at ambients of 16 and 20°C than a

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00327.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.The spectral sensitivity and flicker fusion frequency (FFF) of wild‐type and salmonGlossina morsitans morsitansWestwood (Diptera, Glossinidae) were compared electroretinographically (ERG). Spectral sensitivity curves were similar in shape for dark‐adapted wild‐type and salmon flies, but salmon flies were over 100 times as sensitive as wild‐type flies over much of their sensitivity range. Estimation of the spectral absorption curve (from the differences in ERG sensitivities) for the pigment absent from (or present in low concentration in) the salmon eye suggests that the pigment is an ommochrome. FFF at threshold light intensities was similar in wild‐type and salmon flies, but at higher light intensity (1.3 °W/cm2) the FFF of salmon flies increasedc.200–300%, due to the capacity of the salmon eye to adapt rapidly to the flicker stimulus. Body weight had little effect upon spectral sensitivity and FFF. Wild‐type males were more sensitive to yellow‐green light and had higher FFF than did wild‐type females. Salmon males and females did not differ in spectral sensitivity, but females had higher FFF (when tested with 520‐nm light) than did males. Old wild‐type females did not differ from young females in either spectral sensitivity or FFF. However, old salmon females were more sensitive but had lower FFF than young salmon females. Food deprivation reduced spectral sensitivity and FFF in wild‐type males but not in salmon males. Irradiation (10.5 krad) reduced spectral sensitivity (c.75–375%) and FFF (c.30%) in wild‐type males. The greatly increased spectral sensitivity and FFF in salmon flies indicate that these flies may behave differently from wild‐type flies in the field. Differences in the way spectral sensitivity and flicker discrimination are affected by dark and light adaptation, and by such factors as age and sex, indicate that these measurements ar

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00328.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.In constant light or constant darkness,Glossina morsitans morsitansWestwood were found to exhibit no obvious rhythms of parturition, but in LD 12:12 most larvae were deposited during the photophase. When a divided photoperiod chamber was used to expose the female's head to LD 12:12 and the abdomen (containing the larvaein utero) to constant light, parturition coincided with the photophase of the female's head. But, if the abdomen was exposed to LD 12:12 and the female's head received constant light or was painted with black enamel, parturition coincided with the photophase of the larva. When the female's head and abdomen both received LD 12:12 but 11 h out of phase with each other, parturition was equally frequent in each 12h fraction. The results thus suggest that both the mother and larva are capable of entraining the rhythm, and that in a normal pregnancy both participate in establishing the rhythm.

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00329.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.The responses of adult maleSpodoptera littoralis(Boisd.) (Noctuidae) to components of the female sex pheromone were examined in a wind tunnel. The responses of male moths from both Egyptian and Cretan stocks to the primary ‘attractant’ (Z, E)‐9,11 tetradecadienyl acetate (III), were compared with the responses to III combined with various percentages of the secondary components tetradecyl acetate (I), (Z)‐9‐tetradecenyl acetate (IIA), (E)‐11‐tetradecenyl acetate (IIB), IIA and IIB combined, and(Z, E)‐9,12‐tetradecadienyl acetate (IV). Analysis of the flight behaviour recorded on videotape showed that with one exception (IV), the secondary components increased the males' success in reaching the source and increased the length of time they spent at the source. In most cases, increasing the relative percentage of the secondary component caused a reduction in the number of males responding. The results are compared with those obtained in field trials

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00330.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.Experiments withMacrotermes michaelseni(Sjöstedt), involving artificial groups of different sizes of final larval instar females, showed that the proportion of presoldiers produced in each group decreased exponentially with increase in the size of the colonies. This relationship was not smooth, however, but stepwise. Increasing the number of workers in a group with larvae improved the chance of the larvae differentiating into presoldiers, although the normal proportion of soldiers for the species was not achieved under these conditions, even at maximum crowding. The inhibitory effect of soldiers in stopping larvae differentiating into more soldiers was established, and evidence obtained for a non‐volatile or low volatility pheromone. It is postulated that dominance by larvae which have acquired ‘competence’ over others, allows them to suppress these others from differentiating into presoldiers through the pheromone acting on specific behavioural el

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00331.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.Pupation site preference and body orientation of potato tuber moth larvae,Phthorimaea operculellaZeller (Geleehiidae), were examined in the laboratory. The larvae preferred a dry, enclosed, dark place as their pupation site. Dryness was the strongest of the three categories of stimulus; the second was stimuli evoking thigmotaxis; the third was darkness. Having selected a pupation site, a larva oriented its head to the open side of the site. If two or more openings were present, final orientation was influenced by light and gravity. These preferences and orientation habits enhance pupal protection, and the ultimate successful exit of the adult pupation crevices.

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00332.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.Changes in lift and thrust were elicited in tethered male gypsy moths,Lymantria disparL. (Lepidoptera, Lymantriidae), by visual pattern elements moving radially either towards or from the point directly beneath their body, if the sex‐pheromone, (+)‐disparlure, was present. The sign of these changes was such as to counteract the pattern movements, which were generated by a rotating spiral beneath the moth. By restricting the area of spiral visible to the moth to either transverse or longitudinal sectors, flightaltitudewas affected by the centrifugal/centripetal movements in the lateral sectors, whereas flightspeedwas affected by those in the frontal sector. It is deduced that in free flight these compensatory reactions are responsible for the stabilization of flight altitude and speed, respectively. Surprisingly, without pheromone present these responses were usually not detectable: a wide range of flight altitude and speed was then observed. In the presence of (+)‐disparlure, however, these responses were always strongly pronounced, the animal keeping within a narrow range of speed and altitude. These compensatory reactions were blocked by the attraction‐inhibiting (‐)‐disparlure if presented in racemic mixture with the (+) form: the range of speed and altitude shown by the moth was then the same as without any pheromone. Under closed‐loop conditions, the mean flight speed was reduced by the racemic mixture as well as by (+)‐disparlure

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00333.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.The responseof host‐depibved Rhagoletis pomonellaWalsh (Diptera, Tephritidae) females to host fruit (Crataegus viridisL.) marked withR.pomonellaoviposition deterring pheromone was measured in the laboratory. A positive correlation was found between length of host deprivation (5, 10, 20, 40 or 80 min) and probability of host acceptance (i.e. oviposition) by flies. The results are discussed in relation to current theories on physiological control of insect feeding and oviposition behaviou

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00334.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

ABSTRACT.Under laboratory light: dark cycles, the flight activity of adultLucilia cuprina(Wied.) was low during darkness and uniformity high during light. This pattern persisted as a rhythm both in constant darkness and in constant light of intensity up to 1lx, with a period of approximately 22 h in each. Light pulses of 15 min at l00lx applied to the free‐running rhythm in constant darkness generated phase shifts of up to 60°, 12‐h light pulses of the same intensity generated maximal (180°) phase shifts. The phase response curves had shapes similar to those of a number of other insect rhythms. When exposed to light periods (70 lx) of greater than 12 h followed by constant darkness, the rhythm reinitiated at the light‐dark transition from a constant phase equivalent to that at the time of the light‐dark transition in the LD 12

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1983.tb00335.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY