bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies of British Anthomyiid Flies. IX.—Biology of the Onion Fly, Delia antiqua (Mg.)
Authors: Miles Mary 
Published: July 2009

SummaryThe Onion Fly (Delia antiqua (Mg.)) was bred at Wye, Kent, under insectary and laboratory conditions to obtain further information on its biology and reactions to various temperatures.A comparison of the times of emergence of overwintering generations of Onion Fly and Cabbage Root Fly (Erioischia brassicae (Bch.)) in an insectary showed that the former emerged consistently about a month later than the latter. This supported the observations of previous workers that the Onion Fly was not active in the field until late May.A diet containing protein was necessary for oviposition. The length of the preoviposition period was affected by temperature. Flies maintained at 25°C. laid eggs in 10–24 days, with an average of 15 days. At spring and summer laboratory temperatures (12–29°C.) the preoviposition period was 10–25 days, with an average of 15 days; and in autumn and winter (11–20°) it was 11–46 days with an average of 21 days. Flies maintained at 6–8° did not lay eggs.Flies in captivity laid up to 123 eggs at the rate of 1–45 per day. Intervals between batches of eggs varied from 1–9 days, and the oviposition period was 7–25 days. Flies lived up to 6 days after oviposition.The incubation period depended on the temperature. Eggs at 25°C. hatched in 2 days; at 20° in 3–4 days; at 15° in 4–6 days; and at 7–10° in 9–14 days.The temperature also affected the duration of larval and pupal stages. At 25°C. the successive larval stadia required 2, 2 and 5–9 days, respectively. Lowering the temperature increased the time for development until at 9–11° the three larval stadia required 8–12, 8–18 and 24–37 days, respectively. At 25° the pupal stage lasted 12–17 days; at 20° it was 16–25 days, and at 15° it was from 35 days to over a year. At 25–30° the development from egg to adult was completed in 25 days; at 25° it required 28 days; at 22–27°, 30 days; at 19–24°, 33 days.At 25°C. the Onion Fly bred continuously without diapause. When larvae were reared at temperatures below about 18° pupal development was often retarded. Pupae formed from larvae reared at 12–18° and maintained at approximately that temperature, required 94–442 days to complete their development. By raising the temperature of pupae formed from larvae reared below 18°, it was demonstrated that a true diapause had been induced. Of 54 pupae raised to 25°, 8 (15%) completed their development in the expected time (13–16 days) and 46 (85%) required 94–208 days. Of 322 pupae formed from larvae reared in an insectary in May and June at 10–18° and exposed to July temperatures of 13–20°, 37 (11%) emerged in 25–35 days and 252 (78%) required 234–294 days. Similarly, of 283 pupae formed from larvae reared at 12–21° and exposed to a temperature of 15–23°, 30 (11%) completed their development in 21–31 days while 253 (89%) required 118–341 days. Exposure to low temperatures was not necessary to terminate pupal diapause.
An Account of the Weevil Larvae bred from the Banana Plant in Uganda, with A Description of the Larva of Temnoschoita nigroplagiata (Qued.) (Col., Curc.)
Authors: Whalley Paul E. S. 
Published: July 2009

The two weevils associated with the living stems of the banana plant in Uganda are Cosmopolites sordidus (Germ.) and Temnoschoita nigroplagiata (Qued.); the damage caused by the former has been known for many years but the latter, which usually breeds in rotting stems, has only recently been shown to attack living ones. T. nigroplagiata occurs in every banana-growing area in the territory and is particularly abundant in some parts of western Uganda where C. sordidus, which is otherwise widespread, is rare or absent. Other species of Temnoschoita associated with the banana plant that occur in Uganda but that are rare, are T. basipennis Duv., bred from larvae in rotting pseudostems, and T. erudita, Duv., known only from the adult.The full-grown larva of T. nigroplagiata is described in detail and characters are given for separating the larva and pupa of this species from those of C. sordidus.
Density Distributions of Hoppers of the Red Locust,Nomadacris septemfasciata(Serv.) (Orth., Acrid.), in Relation to Control by Insecticides
Authors: Scheepers C. C. , Eyssell B. J. , Gunn D. L. 
Published: July 2009

In continuation of a study of the process of swarm formation in the Red Locust,Nomadacris septemfasciata(Serv.), to enable rational plans for control measures to be made, the population distribution of about 44½ million hoppers of the Red Locust was investigated in an observation area of 1,052 acres in the Iku outbreak area of the Rukwa Valley, Tanganyika Territory, from 18th January to 24th February 1957. to see if the hoppers showed a tendency to concentrate, which would have the effect of producing, immediately after the last moult, adult swarms from hoppers that were originally more scattered. From 25th January onwards, the estimated population remained constant in numbers. Densities over 50 per sq. yd. were unusual and, taking any continuous infestation over one per sq. yd. as a band, the mean density of hoppers in bands was 15 per sq. yd. There was a tendency for such bands to become larger by fusion and for the area quite free from locusts to increase slightly but the number of dispersed locusts increased. There would therefore have been no advantage in withholding insecticide control in the hope of attacking denser and more economical targets. Nevertheless, such populations have to be controlled.In the Red Locust, under the conditions described, it seems probable that the behaviour of the young adults is most important in the formation of dense swarms, while in certain other species but not in the Red Locust, concentrated egg-laying and the behaviour of the hoppers are also important.Investigations are required on more economical enumeration of patchy gregarious distributions.
An Experimental Campaign with Light Aircraft against Flying Locust Swarms in New South Wales
Authors: Casimir M. 
Published: July 2009

SummaryA campaign in New South Wales against flying swarms of the Australian Plague Locust, Chortoicetes terminifera (Wlk.), using Tiger Moth light aircraft, is described. Large rolling swarms of this locust, travelling across the open plains of western New South Wales, are directed in their general south-easterly move ment by natural barriers in such a way that regular migration routes are followed and predictions of swarm movements can be made. Of particular importance are the timber fringes of creeks and rivers which tend to baulk swarms temporarily and it was in such situations that locust swarms proved most susceptible to treatment by a manoeuvrable aircraft.A technique of drift spraying was developed wherein aircraft were able to operate without ground direction against travelling swarms by spraying at right- angles to the wind direction and by using the main body of the flying locusts for demarcation. Large numbers of short spraying runs were made in rapid succes sion over the most dense portions of the swarm being treated until control was achieved. It was found that the spacing of the runs was not particularly important as long as each was applied to the densest portions of the swarm. The light and relatively slow-moving Tiger Moths proved highly suitable for this work and they were also useful for scouting and keeping track of swarms. Observations made after spraying indicated that the coherent flying swarms treated in the open plains were almost completely eliminated. If, however, swarms were able to reach closely settled or heavily timbered areas they tended to split and disperse and were difficult to treat. The insecticide used was an emulsifiable concentrate containing 7 per cent. γ BHC, which was diluted with diesel oil, and one gallon of liquid containing 5·6 oz. of γ BHC was designed to cover one acre. However, as the campaign progressed, effective use of the spray was probably obtained at less than one gallon per acre, and a total area of 30–37 square miles of dense swarms was treated at a cost of approximately £13,700. There is scope for an improvement in the efficiency of the spraying technique as well as a reduction in some of the major costs in any future campaign.It was considered that the campaign carried out in the Ivanhoe—Hillston district completely controlled all swarms in the area and protected from invasion valuable farming lands to the south-east. Further spraying operations, in the Jerilderie district, 150 miles away, were less successful, although many mor locusts were killed. The spraying party arrived in the district too late to plah a strategic campaign and some swarms escaped treatment.It is concluded that the method of aerial drift spraying is capable of wider application in Australia, particularly in areas where problems of distance, popula tion and lack of facilities militate against successful control by ground machinery.
Injury to Cacao by Amblypelta Stål (Hemiptera, Coreidae) with a Summary of Food-plants of Species of this Genus
Authors: Brown E. S. 
Published: July 2009

Evidence is given, based on, field observations and experiments, of damage to fruits of cacao by two species of Amblypelta (A. theobromae Brown in New Guinea and A. cocophaga China in the British Solomon Islands); the nature of the damage is described.A summary is given of the feeding habits generally, and the effects on the plants attacked, of members of the genus Amblypelta.Comprehensive lists of the known food-plants of each species of Amblypelta are given.
Progress in the Biological Testing of Sorghum Midge (Contarinia spp.)
Authors: Barnes H. F. 
Published: July 2009

Successful emergence of examples of Contarinia sp. and associated parasites has been obtained at Rothamsted Experimental Station from midge-infested heads of sorghum received from India (Mysore State) and West Africa (Ghana).Since typical pre-mating behaviour was observed on all of the few occasions when newly emerged males and females from the two continents were confined together, and actual mating was obtained between a male from Ghana and two females from Mysore in rapid succession, it is concluded that inter-mating will take place under suitable environmental conditions, although in the present series of experiments such conditions were rarely present.It has not yet been possible to test the fertility of such inter-matings or to prove biologically that the species of Contarinia concerned is the C. sorghicola (Coq.) of Texas, although on morphological grounds there are apparently no reasons for their separation.Two species of parasites, a Tetrastichus sp. (group of flavovarius, auct.) and Eupelmus popa Gir., were reared from the Indian material, and another species of Tetrastichus (group of flavovarius, auct.) and E. popa were reared from the West African material.
The Effect of Lizards on the Biological Control of Scale Insects in Bermuda
Authors: Simmonds F. J. 
Published: July 2009

In an intensive study, begun in 1955, on the biological control of Pseudaulacaspis pentagona (Targ.) and Pulvinaria psidii Mask. on oleander (Nerium oleander) in Bermuda, several species of COCCINELLIDAE were successfully established, but none developed a population sufficient to control either scale. The failure of these apparently suitable species of Coccinellids was therefore investigated. It seemed possible that insectivorous lizards, which are very abundant everywhere, might be responsible.Dissection of a number of lizards, Anolis grahami, and A. leachi, in the autumn and winter indicated that at both these times their effect on the natural enemies of scale insects in general and of Pseudaulacaspis pentagona and Pulvinaria psidii in particular, was considerable. Both Coccinellids and Hymenopterous parasites were eaten in large numbers. A surprising number of very small insects including ants, was eaten, and although a number of the insects eaten are harmful, on balance it would appear that, particularly with regard to the biological control of scale insects, the elimination from Bermuda of these lizards, which are introduced species, would be beneficial.Experiments are being carried out to test this, and the introduction of predacious birds, particularly that of the Trinidad kiskadee, Pitangus sulphuratus, is planned.
Rearing and Culturing Musca sorbens Wied. in the Laboratory
Authors: Hafez Mahmoud , Attia M. A. 
Published: July 2009

SummarySeveral artificial media were tested in an attempt to eliminate the use of human faeces as oviposition and early larval habitats for breeding Musca sorbens Wied. in the laboratory. Eggs, laid on cotton-wool pads moistened with diluted milk or, preferably, on small quantities (10–15 g.) of human excrement, were transferred to the breeding medium. The best of those tested was a mixture of coarse wheat bran (120 g.) and diluted milk (240 g.), which yielded normal healthy larvae and adults. The average weight of a puparium produced in this medium was somewhat less than that of one produced in human excrement.
Effects of the Ant, Lasius niger (L.), on the Behaviour and Reproduction of the Black Bean Aphid, Aphis fabae Scop
Authors: Banks C. J. 
Published: July 2009

SummaryCage experiments confirmed that, in the absence of natural enemies, populations of Aphis fabae Scop., attended on bean plants (Vicia faba) by the ant, Lasius niger (L.), multiply more rapidly than otherwise similar but ant-free populations. The average difference in numbers recorded, was about one-third, the maximum being 70 per cent. No doubling or trebling of aphid numbers as claimed by an earlier worker was ever recorded.When the Aphids are attended by ants, their excretion behaviour alters and the normal dispersal of the apterae from the young apical growth of bean plants is considerably delayed.No significant differences were found between the numbers of nymphs produced by individual Aphids from ant-visited and ant-free plants, respectively, living on leaves of the same age; but the numbers were significantly affected by the age of the leaf or part of the plant on which the Aphids had developed or were then feeding.It is suggested that ant-attended aphid populations multiply more rapidly because most of the Aphids feed for a much longer time on young plant tissue where, presumably, their food supply is more nutritious.
First Results in the Control of Simulium damnosum Theobald (Diptera, Simuliidae) in Northern Nigeria
Authors: Crosskey R. W. 
Published: July 2009

An experimental control project against Simulium damnosum Theo. in Northern Nigeria using DDT in diesel oil as a larvicide is described. A description, together with a map, is given of the project area, some 1,200 sq. miles in extent, with a population of 32,000 persons, and it is emphasised that this was selected to provide information on the feasibility of control in an area not isolated from other fly foci.Methods used in applying the larvicide to the rivers, which had rocky beds with rapids and falls, and assessing the effects of treatment are discussed. Applications were made at prearranged treatment points, weekly, for a period of 12 weeks in the dry season of two successive years, 1956 and 1957, and the post-treatment density of adult fly was assessed and compared in a Table and in histograms, with that existing in the year prior to treatment.In the first year, a mean dosage per application of 1·4 p.p.m. of p,p′DDT applied over 30 minutes (S.D. = 0·5 p.p.m.) at each of four treatment points resulted in the clearance of all breeding for a distance of 15–23 miles below these points, and a reduction of adult fly density in the area of 96 per cent. as compared with pre-treatment density. But reinfestation of cleared breeding grounds was found to be rapid, these becoming repopulated with immature stages within six months in spite of a mean wet-season fly density of only 0·35 flies per boy-hour.In the second year, with application of 1 p.p.m. of p,p′DDT for 30 minutes, results were less successful than in the first, although three additional treatment points were used with the aim of controlling a greater distance than in the first year, adult density being only reduced by an estimated 82 per cent. of that before treatment in the first year. The reasons for this are discussed, and the lower degree of control is attributed to the partial failure of the insecticide to reach the breeding sites owing to the exceptionally low state of the rivers.The fly-rounds used in assessing adult density and the pre-treatment breeding sites and the positions of the treatment points are shown on maps. Detailed data from the fly-rounds are given in an Appendix.With the exception of slight mortality among fish, thought to be due to accidental impediments to tbfi free downstream flow of the larvicide, no toxic effects on other organisms were observed.The cost of treatment is given, and the results are discussed briefly in relation to the existing knowledge on control of S. damnosum. It is suggested that control by the application of larvicides in non-isolated foci is a practicable possibility, but that annual treatment might be necessary because of rapid re-establishment in cleared areas. The effect of control, of the degree obtained in this work, on the incidence of human onchocerciasis cannot yet be determined.
The Behaviour of Larvae ofCulicoides circumscriptusKieff. (Dipt., Ceratopogonidae) towards Light Stimuli as influenced by Feeding, with Observations on the Feeding Habits
Authors: Becker P. 
Published: July 2009

The larvae ofCulicoides circumscriptusKieff. are mostly negatively phototactic when extracted from mud and placed in water. Experiments show, however, that if kept without food over a period of time a large proportion becomes positively phototactic. The provision of food causes them to revert to a photonegative taxis which may be permanent as long as suitable food is given, or temporary if the food does not satisfy their nutritional requirements. On the other hand, the provision of a completely non-nutritive medium does not bring about such a reversion. The significance of this behaviour is discussed in the light of the habits of the larvae in the field.Most of the experiments were carried out with batches of fourth-instar larvae, but in a few, third-instar larvae and fourth-instar larvae near to pupation were used. From the results it is suggested that the processes of ecdysis and pupation may bring about a reversal from photonegative to photopositive taxis independent of the need for food.The significance of the behaviour of the larvae towards light stimuli is discussed in relation to their habits in the field. It is assumed that its function is to maintain the larvae on the surface of the mud while feeding and to drive them below when they have fed, and that some other type of tropism must initially drive them to the surface or keep them below according to their nutritional needs.It is shown that the behaviour towards light stimuli of the larvae ofC. maritimusKieff. differs somewhat from that ofC. circumscriptusand reasons are suggested for this.A second series of experiments designed to throw some light on the food requirements of the larvae is described. In a discussion on the results of these it is shown that the larvae feed on material both on the surface of the mud and below the surface, and it is suggested that larvae which have fed on sub-surface food become positively phototactic when they require food from the surface and, having fed there, revert to photonegative behaviour. If, however, photopositive larvae have not previously had the opportunity to feed on sub-surface material they continue to act as completely starved larvae and remain photopositive in spite of their having fed on surface material.The detailed constituents of the larval diet have not been worked out. The larvae appear to be detritus feeders, feeding mainly on vegetable matter and bacteria obtained on or below the surface of the mud, though green algae are not an important part of their diet. They are carnivorous on occasion but are normally not so when other food is readily available. They are selective in their choice of food and at least three factors, sapidity, texture and the size of particles, appear to influence this selection.
Insecticidal Action Studies with Demeton-O and Demeton-S
Authors: David W. A. L. 
Published: July 2009

The two isomers demeton-O and demeton-S which occur as a mixture called demeton in the commercial insecticide Systox act on Aphis fabae Scop. as contact and systemic insecticides and as fumigants.When applied as a contact insecticide or systemically via the roots from solution or from soil, demeton-S was about ten times as toxic to Aphis fabae on broad beans as demeton-O. Using demeton-S containing 32P it was shown that, when applied to the roots, radioactive material passed to all parts of the plants and that the concentration in the aerial parts was higher than in the roots. Leaf samples were more active than stem samples. By radioassay and by the cut tap-root technique it appeared that the lethal dose of demeton-S was equivalent to about 1·0 mg./kg. of fresh plant tissue. The lethal dose of demeton-O by the cut tap-root technique was 3·0 mg./kg. From solutions, the plants first absorbed demeton-S preferentially, then water preferentially. Demeton-S was more rapidly absorbed from sand than from soil.Both isomers were translocated from older to younger leaves of broad beans usually in sufficient quantities to kill Aphids but the results were more consistent with demeton-S. The quantity translocated downwards was small. A low light intensity before and after treatment reduced the quantity of demeton-S translocated. There was also a reduction in the quantity translocated when the plants were only shaded before treatment. One day of shading was sufficient to cause the maximum reduction.Solutions of the two isomers gave off toxic vapours and plants treated via the roots gave off toxic vapours from the foliage.