Showing papers on "Dacus published in 1987"
TL;DR: Most variation in ripe fruit removal by birds was attributed to the interaction of dispersal-related plant traits with insect frugivores that determine post-ripening fruit losses.
Abstract: Avian dispersal of seeds of the wild olive tree (Olea europaea var. sylvestris) was studied in Mediterranean shrubland, southern Spain. Fourteen species of small fru- givorous birds in the genera Sylvia, Turdus, Sturnus, and Erithacus accounted for 97.4% of the fruits consumed by birds. The significance of each bird species as an Olea fruit consumer was closely related to its abundance in the area and was not associated with its dependence on the fruit for food; this resulted in a highly asymmetric interaction between the plant and its dispersers. Fruit production differed greatly between two consecutive seasons. During an extremely dry year most trees aborted their entire fruit crop just after flowering. During the 2nd yr, both flower production and fruit set increased, and this resulted in larger crops of ripe fruit. Most fruits that ripened (96.2% of the final-sized fruits) during the year of low fruit pro- duction were consumed by dispersers (X = 93.9%), and incidence of fruit-damaging agents was low (6.0%). During the 2nd yr, fruit loss to the two main fruit predators, Dacus oleae (Tephritidae) and Prays oleae (Yponomeutidae), increased (X = 27.1%, range 1.1-52.3%). A satiation process took place during this year since fruit production exceeded the energy demand of the disperser assemblage, and this increased the potential for fruit loss to insect frugivores. Fruit removal by dispersers decreased (X = 5 2.4%), but the increase in fecundity during the 2nd yr for most of the trees compensated for this difference and resulted in a greater absolute number of seeds removed. Most variation in ripe fruit removal by birds was attributed to the interaction of dispersal- related plant traits with insect frugivores that determine post-ripening fruit losses. The types of higher order interactions that result from the action of birds, the pulp-damaging fly, and the seed-eating moth larva may damp, or reverse, any selective effect of a single system component on plant traits related to seed dispersal.
203 citations
TL;DR: It is proposed that 2-butanone is an important rendezvous stimulant in nature, bringing the mature male flies into the feeding and oviposition sites (host-trees) of the developing females for mating encounters.
Abstract: Adults of Dacus spp. feed on plant surface bacteria. The responses of D. tryoni (Froggatt) and D. cacuminatus (Hering) to some components of bacterial odours and to cue-lure were tested in a field-cage olfactometer, in studies in south-eastern Queensland. One component of bacterial emission, 2-butanone, attracted D. tryoni (a species responding to cue-lure) but not D. cacuminatus (a species responding to methyl eugenol) and is suggested as the attractive portion of the cue-lure molecule. Sexually mature males and immature females of D. tryoni responded to 2-butanone, cue-lure and bacterial odours in field-cage tests. Females fed on sugar and water required protein hydrolysate to produce eggs, but males were fertile with or without protein. These different nutrient requirements, and the fact that males and females possess different crop colour and bacterial contents when feeding in the same host-plant, indicate that the sexes feed on different substrates. Consequently, the strong bacterial attractant cues in the host-tree may be a feeding attractant to females and a sex attractant to males. It is proposed that 2-butanone is an important rendezvous stimulant in nature, bringing the mature male flies into the feeding and oviposition sites (host-trees) of the developing females for mating encounters.
84 citations
TL;DR: Parasitoids of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and the oriental fruit fly Dacus dorsalis Hendel were monitored on ripe loquat and windfallen peach fruits in the Kula area of Maui, Hawaii, from 1979 through 1985 as discussed by the authors.
Abstract: Parasitoids of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), and the oriental fruit fly, Dacus dorsalis Hendel, were monitored on ripe loquat and wind-fallen peach fruits in the Kula area of Maui, Hawaii, from 1979 through 1985. The percentage of parasitization ranged from 31 to 52% annually. Biosteres arisanus (Sonan), an egg and larva parasitoid, accounted for 74% of the total parasitization, but on several occasions, the larva parasitoids, Biosteres longicaudatus Ashmead and Biosteres tryoni (Cameron), each exceeded 30% parasitism. In most cases, the parasitoid male/female sex ratio was 1:1. The results suggest that opiine parasitoids are important factors in regulating fruit fly populations in Kula, Maui.
77 citations
TL;DR: It is proposed that frugivorous predators are the major natural enemies of larvae of tropical Tephritidae in their endemic habitat in south-east Queensland.
Abstract: The reduction in larval populations of Dacus cacuminatus (Hering) and D. halfordiae (Tryon) by frugivorous vertebrates feeding on their major host fruits was studied in an endemic rainforest habitat in south-east Queensland. Throughout the spring and summer season, 66% of Solanum mauritianum Scop. fruit (D. cacuminatus host) was eaten by Macropygia phasianella (Temminck), the brown pigeon; this increased to 77% during the fruit fly's breeding season (November-January). The peak feeding time of the birds, the breeding season of the flies, and the peak fruiting season of the plants all coincided. Parasitism of D. cacuminatus by Hymenoptera, Biosteres kraussi (Fullaway) and B. oophilus (Fullaway), never exceeded 16-17%. Rodents consumed larvae in 78% of fallen fruit of Planchonella australis (R. Br.) Pierre (D. halfordiae host). It is proposed that frugivorous predators are the major natural enemies of larvae of tropical Tephritidae in their endemic habitat.
62 citations
TL;DR: Mark-release-recapture studies with laboratory-reared irradiated Dacus tryoni (Froggatt) were undertaken in summer in south-eastern Australia and showed that flies can disperse up to 94 km, almost four times the furthest distance recorded previously for this species.
Abstract: Mark-release-recapture studies with laboratory-reared irradiated Dacus tryoni (Froggatt) were undertaken in summer in south-eastern Australia. These showed that flies can disperse up to 94 km, almost four times the furthest distance recorded previously for this species. Most recaptures beyond 6 km were east of the point of release. Several distant traps each caught more than one fly, indicating that the flies moved together over long distances. This suggests that mating could occur and that new infestations could result from the long-distance migration of adults.
45 citations
TL;DR: Doses that caused <25% female mortality significantly reduced fecundity in all three species whether or not males were treated before mating and D. cucurbitae showed greatly reduced fertility regardless of whether treated or untreated males were paired with treated females.
Abstract: Topical toxicity of avermectin B1 to Mediterranean fruit fly, Ceratitis capitata (Wiedemann); oriental fruit fly, Dacus dorsalis Hendel; and melon fly, Dacus cucurbitae Coquillett, was assessed over a 21-d observation period. Mortality stabilized 5–21 d after treatment. LD50’s for female D. dorsalis , D. cucurbitae , and C. capitata were 0.021 μg/g (5 d), 0.042 μg/g (15 d), and 0.29 μg/g (10 d), respectively; LD50’s for male D. dorsalis , D. cucurbitae , and C. capitata were 0.012 μg/g (21 d), 0.025 μg/g (15 d), and 0.58 μg/g (5 d), respectively. Doses that caused <25% female mortality significantly reduced fecundity in all three species whether or not males were treated before mating. Fertility was significantly reduced in D. dorsalis but seemed dependent upon whether males were treated and paired with treated females. D. cucurbitae showed greatly reduced fertility regardless of whether treated or untreated males were paired with treated females. Avermectin B1 treatment also reduced fertility in C. capitata , but the effect was minimal.
45 citations
TL;DR: The CrPV which replicated in the infected flies was demonstrated to be the same as input virus by infection of Drosophila melanogaster cells and examination of the expressed viral proteins, immunoprecipitation of the virus purified from flies, and electrophoretic analysis of the structural proteins.
Abstract: Representatives of several families of insect viruses were tested for growth and pathogenicity in the olive fruit fly, Dacus oleae Gmel. The viruses included nuclear polyhedrosis viruses, an iridovirus, two picornaviruses, and Trichoplusia ni small RNA virus (a member of the Nudaurelia β family), in addition to two naturally occurring viruses of the olive fruit fly. Two viruses, one of the two picornaviruses (cricket paralysis virus [CrPV] and the iridovirus (type 21 from Heliothis armigera), were found to replicate in adult flies. Flies which were fed on a solution containing CrPV for 1 day demonstrated a high mortality with 50% dying within 5 days and nearly 80% dying within 12 days of being fed. The virus was transmissible from infected to noninfected flies by fecal contamination. The CrPV which replicated in the infected flies was demonstrated to be the same as input virus by infection of Drosophila melanogaster cells and examination of the expressed viral proteins, immunoprecipitation of the virus purified from flies, and electrophoretic analysis of the structural proteins.
38 citations
TL;DR: Evidence presented indicates that exposure of wild Queensland fruit files, Dacus tryoni (Froggatt), to a given host fruit type for 3 days causes females to attempt oviposition to a greater degree in that fruit type than in other fruit types.
Abstract: Evidence presented indicates that exposure of wild Queensland fruit files, Dacus tryoni (Froggatt), to a given host fruit type (e.g. pear) for 3 days causes females to attempt oviposition to a greater degree in that fruit type than in other fruit types (e.g. tomato, grape). The effects of exposure to a particular fruit type proved reversible, suggesting that D. tryoni females were capable of learning. Females exposed to pear for 3 days appeared to retain the effect of such exposure on acceptance of tomato for up to 4 days but appeared to retain the effect on acceptance of grape for less than 2 days. The possible significance of prior experience of females with a particular fruit type on future ability to discriminate among varying-quality specimens of that type is discussed.
Resume
Influence de l'apprentissage de Dacus tryoni, lors de la selection de l'espoce des fruits au moment de la ponte
Les elements apportes montrent que l'exposition de D. tryoni Froggat a un type de fruit determinee (par exemple, la poire) pendant 3 jours, conduit la femelle a tenter de pondre a une plus haute frequence dans ce type de fruit que dans d'autres (par example; to-mate ou raisin). Les effets de l'exposition a un type particulier de fruit etant reversibles, ceci suggere que les femelles de D. tryoni sont capables d'apprentissage. Des femelles exposees a des poires pendant 3 jours ont conserve l'effet d'une telle exposition pendant 4 jours en presence de tomates, mais moins de 2 jours en presence de raisin. La discussion porte sur la signification possible de la connaissance anterieure d'un type particulier de fruit sur l'aptitude ulterieure des femelles a distinguer parmi des specimens de ce type, mais de qualites differentes.
35 citations
TL;DR: This review describes the control strategies being developed and in current use—biological, trapping methods, sterile insect release, chemical insecticides, growth regulators and integrated control.
Abstract: Dacus oleae (Gmelin) is a major pest of the olive tree Olea europea causing early fruit drop, ‘sting’ damage to table olives and substantial decreases in the quantity and quality of oil. This review describes the control strategies being developed and in current use—biological, trapping methods, sterile insect release, chemical insecticides, growth regulators and integrated control. Present problems and the implications of the controlling regimes on the disturbance of the agroecosystem are presented. Emphasis is given to newer methods which should be characterized by their specificity and effectivity.
34 citations
TL;DR: The results indicated that medfly host plants were highly variable in distribution, abundance, and fruiting cycle among seasons and years because of climatic factors, especially rainfall.
Abstract: The geographical, seasonal, and annual distributions of Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), populations were monitored for 7 yr (1977–83) by means of traps. containing a male lure to catch flies, and host fruits periodically collected to detect infested fruits in Honolulu and leeward and windward residential areas of the Koolau Mountains of Oahu. Medflies often coexisted in fruit samples with the oriental fruit fly, Dacus dorsalis Hendel, with more oriental fruit flies than medflies reared. Medflies were virtually absent from wet leeward and windward areas of Kaneohe and Kahaluu. The results indicated that medfly host plants were highly variable in distribution, abundance, and fruiting cycle among seasons and years because of climatic factors, especially rainfall. Distribution, dispersal, and abundance of the flies followed the same trends.
27 citations
TL;DR: Malaysian fruit fly, Dacus latifrons (Hendel), has been reared on artificial diet for the first time and results are discussed in relation to mass production of insects for attractants/screening and sterile insect release method (SIRM) programs.
Abstract: Malaysian fruit fly, Dacus latifrons (Hendel), has been reared on artificial diet for the first time. A carrot and a wheat larval diet were used. Larval recovery for both diets was >50%. Fastest development, highest fecundity, and highest fertility were obtained with the wheat diet. Although reproductive parameters for the wheat diet were less than those for a preferred natural larval host, pepper, Capsicum annuum L. variety jalapeno, scarcity of quality peppers in markets favors use of a wheat artificial diet for mass production of D. latifrons . Results are discussed in relation to mass production of insects for attractants/screening and sterile insect release method (SIRM) programs.
TL;DR: The results on the superimposed restricted or unrestricted oviposition indicated that Ethiopian melon fly drastically suppressed the population ofmelon fly.
Abstract: The studies on interspecific competition of melon fly, Dacus cucurbitae Coq, and Ethiopian melon fly D. ciliatus Loew were carried out in the laboratory at 27±2±C and 65±5% R. H. The results on the superimposed restricted or unrestricted oviposition indicated that Ethiopian melon fly drastically suppressed the population of melon fly. The placement of equal number of eggs of both the species in the same fruit also indicated that Ethiopian melon fly larvae suppressed the development of melon fly larvae. Furthermore, lesser preoviposition and incubation periods and more reproductive potential of Ethiopian melon fly contributed towards the suppression of melon fly. It was concluded that the competition between Ethiopian melon fly and melon fly occurred in the larval stage.
Zusammenfassung
Interspezifische Konkurrenz zwischen Dacus cucurbitae Coq. und Dacus ciliatus Loew bei gleichzeitigem Befall von Kurbisfruchten
Die Untersuchungen zur interspezifischen Konkurrenz zwischen Dacus cucurbitae und D. ciliatus wurden im Labor bei 27 ± 2°C, 65 ± 5% R. H. durchgefuhrt. Wie die Ergebnisse einer uneingeschrankten bzw. einer eingeschrankten Eiablage beider Dacus-Arten in jeweils gleiche Fruchte zeigten, unterdruckt D. ciliatus sehr deutlich die Entwicklung von D. cucurbitae. Dies konnte auch durch die Ubertragung einer gleichen Anzahl von Eiern beider Arten in eine Frucht gezeigt werden. Weiterhin ergibt sich aus der kurzeren Entwicklungszeit vor und nach der Eiablage sowie eines groseren Reproduktionsvermogens von D. ciliatus eine Uberlegenheit gegenuber D. cucurbitae. Es wird angenommen, das die Konkurrenz zwischen den beiden Arten im Larvenstadium auftritt.
TL;DR: In vitro translation analysis of RNAs isolated from different developmental stages indicates the presence of translatable serum protein mRNA during the entire pupal period of Dacus oleae.
Abstract: 1. 1. The developmental profiles of the major serum proteins in Dacus oleae were studied. They are first observed in the last stage larvae and after that their concentration increase until the mid-pupal stage. 2. 2. They remain in high concentration until eclosion RNA from fat bodies of late larvae was shown by in vitro translation to contain the mRNA for serum protein. The mRNA has the expected size distribution. 3. 3. In vitro translation analysis of RNAs isolated from different developmental stages indicates the presence of translatable serum protein mRNA during the entire pupal period. 4. 4. This finding is discussed in relation to previous reports on relevant proteins from other insects.
TL;DR: 1981年から1987年まで,約54世代にわたり大量に累代飼育されてきたウリミバエ増殖虫の経過に伴う週別産卵量が寿命の変化について検討した;
Abstract: 1981年から1987年まで,約54世代にわたり大量に累代飼育されてきたウリミバエ増殖虫の世代の経過に伴う週別産卵量と成虫寿命の変化について検討した。大量増殖開始後,約14世代でケージ当り平均産卵量75ml/週の水準に達し,以後,増加の傾向は鈍った。世代が経過するにつれ,成虫は羽化後の早い時期に多く産卵するようになり,同時に寿命が短くなる傾向が認められた。しかし.総産卵量はこれまで安定して確保されてきた。
TL;DR: A model can predict recovery time for flies experiencing a given temperature fluctuation if the length of time spent at the minimum is expressed as a proportion of LE50 at that minimum.
Abstract: Recovery time after experience of a given minimum temperature below torpor threshold is related to the value of that minimum, the length of time spent at that minimum, and the temperature prevailing during the recovery period above torpor threshold. A model can predict recovery time for flies experiencing a given temperature fluctuation if the length of time spent at the minimum is expressed as a proportion of LE50 at that minimum.
TL;DR: Sixteen population samples of Dacus dorsalis from 10 localities in Peninsular Malaysia were analysed for malate dehydrogenase by means of horizontal starch-gel electrophoresis and two distinct zones of MDH activity were present.
Abstract: 1.
1. Sixteen population samples of Dacus dorsalis from 10 localities in Peninsular Malaysia were analysed for malate dehydrogenase by means of horizontal starch-gel electrophoresis.
2.
2. Two distinct zones (loci) of MDH activity were present.
3.
3. Both Mdh loci were polymorphic. The MDH-1 electromorphs were governed by three codominant alleles, while the MDH-2 electromorphs were governed by eight alleles.
4.
4. Mdh-1100 and Mdh-2100 were the commonest alleles in all the population samples. They encoded an electrophoretic band with intermediate mobility.
5.
5. Both Mdh loci showed low variability.
TL;DR: Tests with the oriental fruit fly showed no survival of adult flies from treated fruits, although the dosages required were an order of magnitude greater than those needed for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann).
Abstract: The life cycle of the oriental fruit fly, Dacus dorsalis Hendel, in papayas was completely interrupted by a coating of a standard commercial fruit wax containing the insect growth regulator, methoprene. Tests with the oriental fruit fly showed no survival of adult flies from treated fruits, although the dosages required were an order of magnitude greater than those needed for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann).
TL;DR: It’s time to get used to the idea of “novelty”.
Abstract: ウリミバエの大量増殖系統と野生系統の繁殖と生存にかかわる諸形質の変異性を比較した。大量増殖系統は1979年12月に野外より採集し,羽化後3週目の卵のみを次世代虫とする方法で,産卵効率の高い個体を選択し,育成したものである。実験に供するまでに約20世代累代飼育されている。野生系統はニガウリの寄生果を採集し,羽化させた直後の成虫である。比較の対象にした形質は産卵前期間,生存期間中の総産卵数,産卵回数,産卵個体率,産卵後期間,交尾前期間,交尾回数,および雌雄の生存日数である。1) 大量増殖系統の産卵前期間,産卵後期間,および雌雄の生存日数はいずれも野生系統よりも短かかった。2) 大量増殖系統の総産卵数は野生系統よりも多く,また産卵個体率も高かった。3) 産卵回数および交尾回数はいずれも大量増殖系統において野生系統よりも多かった。4) 野生系統の産卵前期間,総産卵数,産卵回数,産卵個体率,産卵後期間および交尾回数の変動係数は大量増殖系統よりも高かった。5) 交尾前期間,および雌雄の寿命の変動係数は両系統とも近似していた。以上の結果,大量増殖系統は野生系統に比べて早熟,多産,早死であり,一般に繁殖と生存にかかわる形質の変異性の低いことが示唆された。
TL;DR: Soil samples taken in the field under olive trees showed that pupae and empty puparia were mainly found in depths ranging from 2.5 to 7.5 cm, and recommendations to reduce the olive fruit fly populations are suggested.
Abstract: Soil samples taken in the field under olive trees showed that pupae and empty puparia were mainly found in depths ranging from 2.5 to 7.5 cm. Similar trend were found when pupae placed in the field under olive trees. Pupae in the infested olive fruits were first detected in early July, but few numbers were found in the collected fruits from under the olive trees in January and February. Recommendations to reduce the olive fruit fly populations are suggested.
Zusammenfassung
Untersuchungen zur Verpuppung der Olivenfruchtfliege, Dacus oleae Gmel. (Dipt., Tephritidae)
Anhand von Bodenproben, die im Freiland unter Olivenbaumen genommen wurden, konnte festgestellt werden, das in 2,5–7,5 cm Tiefe die meisten Puppen und leeren Puppenhulsen auftreten. Eine ahnliche Tendenz zeigte sich, wenn Puppen unter Olivenbaume eingegraben wurden. In befallenen Olivenfruchten wurden Anfang Juli die ersten Puppen gefunden, im Januar und Februar konnten nur noch wenige in Fruchten, die unter den Baumen gesammelt wurden, gefunden werden. Abschliesend werden Empfehlungen zur Reduktion der Olivenfruchtfliegen-Population gegeben.
TL;DR: Histological study of the rectum of this species revealed a sexual dimorphism of that organ, and the presence of tissue in the male similar to that which has been described as a pheromone gland in related species.
Abstract: Dacus latifrons (Hendel) is a species of tephritid fruit fly recently introduced into Hawaii. Histological study of the rectum of this species revealed a sexual dimorphism of that organ, and the presence of tissue in the male similar to that which has been described as a pheromone gland in related species. The musculature of the wall of the rectum of the females is much thicker than in the male.
TL;DR: Papaya fruits infested with eggs of the oriental fruit fly were exposed to a variety of double hot-water immersion treatments, and larval survival rates were measured using a mathematical model developed to calculate survival rates.
Abstract: Papaya fruits infested with eggs of the oriental fruit fly, Dacus dorsalis Hendel , were exposed to a variety of double hot-water immersion treatments, and larval survival rates were measured. Using measurements of egg number as a function of fruit depth, a mathematical model was developed to calculate survival rates. Predictions compared favorably with the experimental results.
Journal Article•
TL;DR: Pupae from several stocks of wild and laboratory reared olive fruit fly, Dacus oleae, were fractionated by a series of steps designed to identify occluded and nonoccluded viruses to inapparently infect a Ceratitis capitata continuous cell line.
Abstract: Pupae from several stocks of wild and laboratory reared olive fruit fly, Dacus oleae, were fractionated by a series of steps designed to identify occluded and nonoccluded viruses. Two different size of particles were isolated, the smaller of which contained a single-stranded RNA molecule of about 2.8 x 10(6). This small RNA virus was found to inapparently infect a Ceratitis capitata continuous cell line.