摘要:

ABSTRACT.The sexual response of aGlossina morsitans morsitansWestw. male towards a decoy consisting of a dead male dosed with synthetic sex pheromone, was depressed by the presence of the cuticular lipids of the decoy male. However, addition of a C24 paraffin, not normally found on or in the cuticle of male or femaleG.m.morsitans, to a decoy male from which cuticular lipids were removed had a similar effect. Addition of either the C24 paraffin or an extract of male cuticular lipids to decoy females which possess natural sex pheromone in their cuticles, again depressed the sexual responses of males towards the decoys. The n‐hexane solvent used in the application of compounds to decoys, itself depressed responses towards natural pheromone on a dead female at volumes in excess of 100μl, presumably because it mixed the surface waxes which masked the pheromone. Occlusion experiments implied that sex pheromone receptors are present on both the tarsi and tibiae of the male. No evidence was found for the existence of a specific mating deterrent on or in the cuticle of maleG.m. morsita

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00296.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.The behaviour ofTrialeurodes vaporariorum(Westwood) (Homoptera, Aleyrodidae) in violet and green light (400 and 550 nm) was examined using several responses. Under 400 nm the whiteflies took‐off more readily and walked faster than under 500 nm. In flight, they oriented towards 400 nm when simultaneously illuminated with equal quanta of 550 and 400 nm light. The ecological significance of this behaviour is discussed, and it is concluded that in nature flying adults would orient towards the sky (i.e.c.400 nm) but would tend to land on a green plant because plants reflect maximally at 550 nm. Once landed on a suitable food‐plant the position on that plant where the insect finally feeds and reproduces is probably also determined by visual stimuli, since whiteflies will walk to the shaded side of a leaf regardless of whether that is below or ab

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00297.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.The initiation and pattern of embryonic development inLeptophyes punctatissima(Bosc) (Tettigoniidae) are shown to be variously dependent on temperature. Immediate high temperature (30°C) facilitated rapid and direct embryogenesis to the stage of diapause in the fully formed embryo. Slightly lower temperature (25°C) resulted in a delay before embryogenesis started, and this delay was greatly extended as an initial diapause if incubation temperatures were decreased (20‐16°C). Still lower initial temperatures (8–12°C) facilitated subsequent development at 20–30°C. These responses all increased as a function of exposure time. Once initiated, the rate of development was temperature dependent, but competence to tolerate high temperature, and ability to continue development at low temperatures, changed with age. In general, the developmental temperature range appears to be lowered with age. None of these different treatments had any effect on the late embryonic diapause. According to the temperatures prevailing at oviposition,Leptophyescould be an annual or a biennial species; the biennial pattern

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00298.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.Differences in the weight of parasitoid individuals ofBrachymeria intermedia(Nees) (Chalcidae) andCoccygomimus turionellae(L.) (Ichneumonidae) were found to be associated with differences in host diet. The availability of the host nitrogen to the parasitoids differed depending on the sex of the host,Lymantria dispar, and its diet. Nitrogen utilization efficiency (NUE) for both parasitoid species were inversely correlated with host weight and with host nitrogen. Values for NUE are lower than those reported for phytophagous insects such as Lepidoptera.

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00299.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.Ecdysteroid titres were determined in testes, fat body, muscles, haemolymph, carcass tissue, spermatophores, and faeces of males of the Mediterranean field cricket,Gryllus bimaculatusde Geer, throughout its adult life span. Considerable amounts of free ecdysteroids are concentrated in the testes and the fat body. The ecdysteroid titres were only slightly influenced by environmental temperature. In all tissues except the fat body, ecdysone and 20‐hydroxyecdysone were the predominant ecdysteroids present. In faeces, highest ecdysteroid concentrations were found at the time of lowest levels in tissue

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00300.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.In both virgin and inseminated femaleCulex pipiens quinquefasciatusSay, circadian flight‐activity has two major components: evening (E) and morning (M) in virgins, and evening (E) and night (N) in inseminated females. These components probably represent the activity of constituent oscillators of the underlying pacemaker system. In DD (constant dark) the E and M peaks are approximately 12 h apart in virgins, the E and N peaks 6–7 h apart in inseminated females. Entrainment to regimes between LD 6:18 and 18:6 appears to have only small effects on the relative position of these components, and after a change to DD they quickly relax towards a common phase‐relation. Entrainment to LD 12:12 followed by release into DD or constant dim light (intensities 0.005‐5 be) showed that light has a differential effect on the components, initially increasing the period of the E component more than that of the apparently more stable M and N components. Thus with increasing light intensity a bimodal cycle fuses into a unimodal cycle. Light also affected the level of activity, causing big increases in the activity of both virgin and inseminated females at 0.05 lx, but depressing activity, at least initially, at 5 lx. These results indicate that, under natural conditions, moonlight may have big effects, both on the level of activity and on the underlying circadian pa

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00301.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.Regular flight exercise of adult maleLocusta migratoria migratorioides(R and F) accelerated the development of maximum flight speed and disrupted the development of the typical pattern of change of flight speed exhibited when normal (untrained) adult male laboratory locusts are flown on roundabouts. Thus, while untrained mature locusts fly fast initially and then slow to a steady cruising speed after 20 min, trained locusts flew at a relatively constant speed throughout a 60‐min test period. Flight training also led to a marked reduction in the size of the fat body and the flight muscles, but flight muscle ultrastructural development was not affected. Regular flight exercise had no long‐term effect on haemolymph carbohydrate concentration but lipid levels were significantly depres

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00302.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.The morphology of the palp joints inGryllus bimaculatusDeGeer is described in the context of their use in various behavioural situations. Two patterns of movements are distinguished: the goal‐directed movement of each individual palp, as seen during grooming and food intake actions, and the rhythmic probing movement of the two maxillary palps together during exploratory behaviour and walking. Their details were studied by single frame analysis of video and cine records. The functional characteristics of the maxillary palps with regard to the dimensions of space within which they move in these patterns (‘operational space’) and the potential sensory stimuli they receive (‘reception space’) are compared with those of the antennae and discussed from the viewpoint of division

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00303.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.The behaviour of the carrot fly larva,Psila rosaeF. (Diptera, Psilidae), was investigated in the presence of six concentrations of thirty‐four volatiles associated with carrot root and oftrans‐methyl‐iso‐eugenol, a constituent of carrot herb oil. Bomyl acetate, 2,4‐dimethyl styrene, α‐ionone, SbT‐ionone and biphenyl were the most consistently preferred compounds. Klinotaxis and klinokinesis were the orientation responses near the stimulus source.Trans‐2‐nonenal was the most consistently avoided compound. Extracts derived by steam distillation of carrot roots and by concentration of vapour from roots were resolved, by gas liquid chromatography, into forty‐five and twenty‐two major constituents, respectively. The five preferred compounds are micro‐components of these extracts, collectively representing 1% and 0.6% of root extract oil and vapour, respectively. It is suggested that these secondary plant constituents are specific host finding cues for the larva, and that frara‐2‐nonenal

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00304.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

ABSTRACT.Feeding patterns ofLocusta migratoriaL. nymphs, kept under LD 12:12 at 30°C with ample food, were analysed over the first 6 days of the fifth instar. A number of differences were found between the light and dark phases. (1) More was eaten during the light than the dark, with the differences becoming progressively larger over the 6 days. (2) During light phases most insects showed an increasing tendency to feed with time since the last meal, while in the dark the probability of starting to feed remained constant. (3) There was little variation in feeding patterns within the light phase, but marked changes occurred within the dark phase, feeding declining to a low level in the last 4h. The amount eaten during a meal was regulated similarly in the light and dark, with time rather than amount eaten being of paramount importance in terminating a meal. The time when feeding started was somewhat influenced by the size of the preceding meal, but once feeding began meal size was largely independent of the preceding meal. The importance of food quality in determining the pattern of feeding is discussed

ISSN:0307-6962    

DOI:10.1111/j.1365-3032.1982.tb00305.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY