Abstract: Selection at the alcohol dehydrogenase locus of the olive fruit fly Dacus oleae under artificial rearing

Abstract: Two novel hydroxyspiroacetals, 3- and 4-hydroxy-1,7-dioxaspiro[5.5]undecane have been isolated from the rectal gland of the female olive fly (Dacus oleae) and a stereoselective synthesis of the latter developed.

Abstract: High densities (12 or more) of Dacus cucurbitae eggs per 18 mm diam host fruit resulted in fewer numbers (per egg basis) and reduced size of adult progeny compared with a lower egg density. Observational and experimental evidence indicated (a) the absence of any female-deposited substance of pheromonal nature or fruit origin which influenced frequency of female arrivals, oviposition attempts, or number of eggs laid in high egg density fruit, but (b) the ability of ♀♀ to detect high densities of conspecific larvae (or larval infested fruit) and refrain from ovipositing in such. We suggest that in many circumstances, the latter capability may be sufficient to prevent overcrowding of host fruit and permit partitioning of D. cucurbitae oviposition among sites conducive to development of fit progeny. ZUSAMMENFASSUNG Aufteilung der Eiablageorte bei Dacus cucurbitae Hohe Dichten (12 und mehr) von Dacus cucurbitae Eiern pro 18 mm Fruchtdurchmesser ergaben eine geringere Zahl (pro Ei-Basis) und eine geringere Grosse der adulten Nachkommenschaft als niedrigere Dichten. Beobachtungen und Versuche zeigten: a) Die Abwesenheit von durch Weibchen applizierten Substanzen mit Pheromoncharakter oder mit Herkunft von Fruchten, welche die Haufigkeit der Landungen der Weibchen, die Eiablageversuche oder die Zahl der auf dichtbesetzten Fruchten gelegten Eier beeinflussten, b) Die Fahigkeit der Weibchen hohe Dichten konspezifischer Larven (oder von Larven befallenen Fruchten) festzustellen und bei der Eiablage zu meiden. Wir vermuten, dass letzteres in vielen Fallen genugt um Uberbelegung von Wirtspflanzen zu vermeiden und um die Aufteilung der Eiablage auf solche Stellen zu erlauben, welche die Entwicklung einer leistungsfahigen Nachkommenschaft gestatten.

Abstract: A 15-min, 50°C hot-water immersion treatment was developed as an alternative quarantine treatment to ethylene dibromide fumigation for ‘Brazilian’ variety bananas against the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), the melon fly, Dacus cucurbitae Coquillett, and the oriental fruit fly, D. dorsalis Hendel. The hot-water immersion disinfested ‘Brazilian’ variety bananas without detriment to either fruit quality or shelf life.

Abstract: Dacus dorsalis Hend. infested eleven, D. cucurbitae Coq. five and D. umbrosus F. two of the eighteen common fruits and vegetables grown in Penang, West Malaysia. D. tau (Wlk.) infested bacang (Mangifera foetida), D. caudatus F. chilli (Capsicum annuum) and D. frauenfeldi Schin. water guava (Eugenia javanica), together with D. dorsalis. Pomelo (Citrus grandis) was found infested for the first time by D. cucurbitae. No flies were trapped using Capilure and trimedlure as baits. Cue-lure attracted D. caudatus, D. cucurbitae, D. frauenfeldi, D. occipitalis (Bez.) and D. tau. Methyl eugenol attracted D. dorsalis and D. umbrosus. Dorsalure was less attractive to D. caudatus and D. dorsalis than cue-lure and methyl eugenol, respectively, but it was equally attractive to D. frauenfeldi as cue-lure. Using traps baited with cue-lure or methyl eugenol in five ecosystems, the highest numbers of males of D. dorsalis, D. umbrosus, D. frauenfeldi and D. caudatus trapped were from a village, on a vegetable farm for D. cucurbitae, and D. occipitalis was only caught in a forest. Analysis showed that for each species of Dacus the difference between ecosystems was highly significant. The few examples caught in grassland were probably migrants.

Abstract: The mating patterns of wild oriental fruit flies, Dacus dorsalis Hendel, were compared with those of a 28-year-old laboratory strain. In the laboratory, 100% of the laboratory-reared females were mated by day 12 postemergence, whereas only 2.5% of females of the wild strain were mated 13 days postemergence. Laboratory tests indicated a partial sexual isolation between the laboratory-reared males and wild females—in the cross mating, only 50% were mated by day 24 of adult life. In the cross mating between wild males and laboratory-reared females, and in the mating of wild males and wild females, 90% mating was obtained by day 24. Further evidence of sexual isolation between the two strains was obtained in field cage tests. When laboratory-reared flies that had been irradiated with 10 krad in N2 were released in field cages with normal wild flies, the results were similar to those obtained from laboratory-reared flies that were unirradiated with normal wild flies. The results of both field tests showed that significantly more males mated with females of the same strain than cross matings.

Abstract: During July to September 1977, fruits of variety ‘59-656’ of pineapple, Ananas comosus (L.) Merr., were collected from experimental plantings in commercial acreage at Kunia on the island of Oahu, Hawaii. Variety ‘59-656’ was studied for resistance to melon flies, Dacus cucurbitae Coquillett, and oriental fruit flies, D. dorsalis Hendel. Data were compared with those from previous studies of the standard ‘Smooth Cayenne’ variety of pineapple. Although pineapple hybrid ‘59-656’ was exposed to field populations of both fruit fly species, no larvae or pupae developed from any of the 500 pineapples collected. Thus, this new variety is apparently not a host for melon flies or oriental fruit flies.

Abstract: MONTIEL, A.; RAMOS, P.; JONES, O. T ; LISK, P. E. y BAKER, R., 1982: Interferencias en el apareamiento de la mosca del olivo (Dacus oleae Gmel.) con el principal componente de su feromona sexual. Bol. Serv. Plagas, 8: 193-200. The major component of the sex pheromone of Dacus oleae was formulated in plastic sachets which provided a more or less constant release rate over 30 days under Laboratory conditions. Using one or two sachets per olive tree, mating disruption was achieved in both 1981 and 1982 in one hectare sites in Granada and Jaen (Spain). This was assayed by depression of captures in pheromone-baited traps in the treated pit. During 1982, measurements of fruit infestation in treated and control sites was also made which provided further evidence that mating disruption was achieved. Although there were high significant differences in trap catches in treated and untreated plots, signigicant differences in infestation levels have not yet been established conclusively in D. oleae.

Abstract: Aus den Rektaldrusen von weiblichen Oliven?iegen werden die Hydroxyspiroacetale (I) isoliert.

Abstract: Twenty-seven specimens in the University of Queensland Tephritidae collection determined by Francis Walker have been restudied and placed in their correct combinations. Eighteen species are represented, all except 2 described by Walker. Only Adrama selecta Walker, Dacus curcubitae Coquillett, Dacus determinatus Walker, Dasyneura zonata Saunders, Sophira punctifera Walker, Strumeta helomyzoides Walker and Trypeta multistriga Walker are Tephritidae. The other 11, originally described as new species of Dacus F., are Platystomatidae.

Abstract: The mass-rearing of insects is necessary for the integrated pest management using augmentation of parasites or predaters and release of sterile or geneticalJy altered insects. In the earlier time, the primary problem in the mass-rearing was how to enhance the productivity of the rearing under low cost conditions6>. For this purpose, individuals having high fecundity were selected from the wild population in the course of colonization in laboratory and mass-rearing. However, this selection may also alter other characteristics of the insects. Boller2> pointed out the importance of behavioral aspects of massrearing of insects. Insects mass-reared should perform their typical behavior after released in the field. Some signs of deterioration in this typical behavior have been detected from the mass-reared insects. From the above point of view, quality problems have been concerned in the mass-rearing of insects3l. In the sterile insect technique (SIT) , the quality of sterile insects should be evaluated ultimately as sexual competitiveness under · the field conditions5>. Huettel4> defined two types of quality, those are, 'overall quality' and 'quality of specific traits'. The sexual competitiveness of sterile insects in the field conditions seems to correspond to 'overall quality'. When we consider the quality monitoring, 'quality of specific traits' should be measured. If quality of each specific trait for sterile insects released resemble that for the wild insects, we can expect the flies released have high 'overalJ quality', then they perform well their role in the field. If we find deterioration in a specific trait, the cause of such deterioration should be investigated and the method for mass-rearing should be improved. In the SIT program of the melon fly, Dacus cucurbitae Coquillett, on Kume Island, Okinawa, Japan, the wild melon flies were collected and colonized in 1972. The flies had been reared in the laboratory with an artificial conditions for 13 generations, and then massreared in the mass rearing facility in Yaeyama Branch of Okinawa Prefectural Agricultural Experiment Station, Ishigaki, Okinawa, Japan, for about 44 generations till November, 1979 (old strain). The rearing conditions were described by Nakamori and Kakinohana7>. From 1978 to 1979, a new strain was colonized in the mass-rearing facility, and was replaced for the old strain10l. From the stand point of quality problems, experiments were conducted for comparing several traits among mass-reared strains (old and new) and wild ones. In this report, the results of these experiments will be reviewed. In the following sections, 'wild strain' is adult flies collected from field in Okinawa or Ishigaki Islands as larvae and reared in the laboratory conditions for 03 generations with pumpkin fruit, a natural diet, for larvae, and sugar, protein hydrolysate and water for adult diets. The number of generations reared under mass-rearing conditions for mass-reared strains will be shown in each experiment.

Abstract: The 3 tephritids in Hawaii of economic importance, namely the Mediterranean fruit fly (medfly), Ceratltls capltata (Wiedemann), the oriental fruit fly, Dacus dorsalis Hendel, and the melon fly, D. cucurbitae Coquillett, showed marked differences in species‐, age‐, and sex‐specific susceptibilities to CO2 anesthetization. Mortalities for medflies exposed to CO2 increased more with time than did mortalities for the other 2 species. Older medflies and oriental fruit flies were more susceptible to CO2 exposure than were younger flies. Female medflies and oriental fruit flies were generally affected more by CO2 exposure than were males. Melon files were the least affected of the tested species by anesthetization with CO2.

Abstract: . The tethered flight of the Queensland fruit fly, Dacus tryoni Frogg. (Diptera, Tephritidae), was investigated, and the duration of each flight during a 2-h experimental period was recorded. The pattern of flight was analysed, and related to the age, sex and origin of the specimens, and to the availability of host fruit during the rearing of the adults. The effect of adult crowding on the pattern of flight was also briefly examined. The results indicated that the origin of the flies had little effect on the pattern of flight; male and female flies showed different trends with respect to the proportion of short flights undertaken as the flies matured; and the availability of fruit had a marked effect on the pattern of flight in recently mature flies. These data are discussed with respect to the dispersive/non-dispersive movements of the flies postulated from previously documented field data. It is suggested that there is a characteristic pattern of tethered flight, which can be related to the absence of hosts in the immediate environment, and would be likely to lead to greater dispersal under natural conditions.