bluuebunny/crossref_metadata_2025 huggingface dataset:
Field application and effects of chlorpyrifos residues onSitona discoideus(Coleoptera: Curculionidae) adults and implications for biological control byMicroctonus aethiopoides(Hymenoptera: Braconidae)
Authors: McNeill M.R. , Hunt L.M. , Chapman R.B.
Published: July 2009

Chlorpyrifos was applied to field lucerne at a rate (0.3 kg/ha) recommended to control the weevilSitona discoideusGyllenhal. The fate of the weevil population and that of the immature stages of its parasitoidMicroctonus aethiopoidesLoan were examined by field sampling. A single application of chlorpyrifos reduced the weevil population by 96.2% 14 days after application. There was no significant decline in the control population between sampling intervals nor a change in the parasitism levels. However, in the insecticide-treated plotsc. 88% of survivors (n=8) were parasitized. The effects of chlorpyrifos residues at 0.3 and 1.0 kg/ha were also examined. At the lower rate, residues producedc. 40–60% weevil mortality for up to 15 days after application although a significant decline in activity only occurred between days 1 and 3. At 1.0 kg/ha, the activity decay curve was much slower with no significant decline in weevil mortality for the first 15 days of the experiment. Weevil gender was shown to be a significant factor influencing mortality. Mortality of unparasitized weevils was also significantly greater than for parasitized hosts while the stage of parasitoid development had a significant effect on mortality. Where parasitoid development was sufficiently advanced, late-instar larva emerged and successfully pupated from cadavers up to 18 h following host mortality. The consequences of applying insecticide to controlS. discoideusas they relate to the parasitoid and the success of biological control are discussed.
Studies on the Sex pheromone of the diamondback moth Plutella xylostella (Lepidoptera: Yponomeutidae) in India
Authors: Reddy G.V.P. , Urs K.C.D.
Published: July 2009

Marked male moths of Plutella xylostella (Linnaeus) released at up to 12 m from a sticky delta trap baited with synthetic pheromone, were caught in significantly higher numbers than moths released at greater distances, both in downwind and upwind directions, from the traps. Maximum catches were obtained when the traps were set at 30 cm above the crop level. Continued exposure of septa in the field led to a progressive reduction in catches, and catches were significantly reduced after 28 days. Newly emerged virgin female moths attracted significantly more male moths than one day old or older virgin female moths. Five day old virgin females attracted no male moths. When virgin females were used as a bait in the field, the peak catch of males was between 1600 and 1800 h. Tests at two field locations revealed that, at the concentration tested, synthetic sex pheromone attracted a similar number of moths to the number attracted by 10 virgin females in delta traps, and significantly more than 8, or fewer virgin females.
A brief account of the hibiscus mealybugMaconellicoccus hirsutus(Hemiptera: Pseudococcidae), a pest of agriculture and horticulture, with descriptions of two related species from southern Asia
Authors: Williams D.J.
Published: July 2009

The mealybugMaconellicoccus hirsutus(Green) occurs in many tropical and subtropical parts of the Old World and extends into some temperate areas. It has now reached the West Indies where it is causing extensive damage to plants. There is concern that it may be introduced to the southern USA and to Central and South America. A brief account is given of reported damage caused byM. hirsutusto some commercial and food crops in Asia and Africa and the species is redescribed.M. multipori(Takahashi), now known from a wide area in southern Asia, is redescribed, andM. ramchensissp. n.from Nepal, is described as new. These two species are closely related toM. hirsutusand can easily be mistaken for it.M. hirsutusandM. multiporiare sometimes intercepted at quarantine inspection of plants and plant produce in the USA and Europe. In order to aid identification, a key is provided to the eight species presently included in the genusMaconellicoccusEzzat.
The Transmission of Bancroftial Filariasis on Ukara Island, Tanganyika. III.—Biting-incidences on Man and Filarial Infections in wild-caught Mosquitos
Authors: Smith A.
Published: July 2009

The seasonal biting-incidences on man of several species of mosquito inside and outside huts of villages on Ukara Island, Tanganyika, between 7 p.m. and 3 a.m. East African Standard Time are recorded. Anopheles gambiae Giles and A. funestus Giles were by far the most common indoor biters in both of the villages which received study: they were also taken biting outdoors in fair numbers. Tacniorhynchus africanus (Theo.) and T. uniformis (Theo.) were common outdoor biters in a village near a swamp, but were taken in only small numbers off human “bait” in a cone hut.

A study of sleeping arrangements in huts showed that people between six and sixteen years of age were most exposed to the risk of mosquito bites at night, since they were least protected by covers and clothing.

The inhabitants were bitten by Aëdes africanus (Theo.) and Aë. apicoargenteus (Theo.) outdoors by day, and by small numbers of A. gambiae and A. funestus in huts during daylight hours in April.

The results are given in detail of dissections for developing filarial worms in over seven thousand mosquitos. Proboscis infections occurred in A. gambiae and A. funestus. Immature (thoracic) forms were found in A. pharoensis Theo., T. africanus, T. uniformis and Culex antennatus (Beck.).

It is concluded that the biting-habits of A. gambiae and A. funestus point to them as more likely vectors of bancroftial filariasis than other species with developing filarial worms.
On The Transmission of Bancroftial Filariasis on Ukara Island, Tanganyika. IV.—Host-preferences of Mosquitos and the Incrimination of Anopheles gambiae Giles and A. funestus Giles as Vectors of Bancroftial Filariasis
Authors: Smith A.
Published: July 2009

Precipitin tests show that, on Ukara Island, Tanganyika, man and ox are the chief sources of blood to hut-resting mosquitos. Anopheles gambiae Giles and A. funestus Giles feed almost entirely on man. A. pharoensis Theo. feeds more on man than on ox. Culicines feed more on ox than on man.

Hand-catches off man, cow and goat in a hut confirm the results of precipitin tests on hut-resting mosquitos.

An account is given of the mosquito fauna of natural and artificial outdoor resting places and of the results obtained in precipitin tests on blood-fed mosquitos from outdoor resting places.

Blood-fed mosquitos resting indoors and outdoors were examined for nucleated red corpuscles in blood-meals. A. gambiae and Gulex annulioris Theo. feed on domestic fowl.

Experiments in the laboratory, to find the facility with which different species of mosquito will feed on small wild animals of the island, show that A. gambiae and certain Culicines feed on a wide variety of hosts.

A. gambiae and A. funestus are incriminated as almost entirely responsible for the transmission of bancroftial filariasis on Ukara Island. A little transmission may take place by A. pharoensis.
An Ecological Study of Coccinellidae (Col.) associated with Aphis fabae Scop. on Vicia faba
Authors: Banks C. J.
Published: July 2009

Changes in numbers of adult Coccinellids on nettles infested with Microlophium evansi (Theo.) and on three experimental bean plots infested with Aphis fabae Scop. are described for the spring and summer of 1952 at Rothamsted. Of the three common species, Adalia bipunctata (L.), Coccinella septempunctata L. and Propylea quatuordecimpunctata (L.), the first was always the most abundant.

The overwintered Coccinellids produced two broods: one on nettles in the spring and one on beans in early summer.

On bean plots, changes in numbers of the adult insects occurred in three phases: (1) overwintered ladybirds, dispersing from nettles and other places, accumulated on the beans in the early stages of the infestations by Aphis fabae; (2) ladybirds, which had developed from eggs laid by the overwintered insects on nettles, emigrated from nettles and accumulated on the beans when A. fabae populations were at their height; (3) ladybirds, developed from eggs laid on the beans also by the overwintered insects, reached the adult stage when the bean aphid infestations had finished. The rise and fall of the A. fabae populations are discussed.

One of the bean plots had always a high population of Coceinellids, which was attributed to its situation between two of the nettle sites. The other two bean plots were remote from nettles and one was sheltered by trees and buildings; their coccinellid populations were much lower.
Experiments in Tsetse Control in southern Tanganyika
Authors: Bursell E.
Published: July 2009

A recent extension of the fly-belt in Songea, southern Tanganyika, has been delimited.

The preferred habitat of the tsetse in this region is constituted by open, short-grassed glades, representing old village sites, in well-grown Brachystegia woodland, with a double-canopied interzone between glade and woodland.

Destruction of this interzone by clearing of the upper canopy will undoubtedly prove effective in causing eradication of the fly.
Insecticidal Dusts for the Protection of Stored Peas and Beans against Bruchid Infestation
Authors: Parkin E. A. , Bills G. T.
Published: July 2009

Laboratory tests are described for determining the protective value of a number of physically and chemically active insecticidal dusts against Bruchid infestation of peas and beans. Acanthoscelides obtectus (Say) and Callosobruchus chinensis (L.) were used as the test insects and were found to be very susceptible to most of the treatments tried. Adults of A. obtectus were in general more resistant to the treatments than those of C. chinensis, but the multiplication of the former species was more easily stopped, apparently because of the vulnerability of its first-stage larvae. It is concluded that protection of peas and beans can be achieved by thoroughly mixing into 200 lb. of the commodity 6–8 oz. of one of the following dusts: colloidal silica, colloidal aluminium pentasilicate, finely ground diatomite, 0.05 per cent. y BHC (as lindane) on diatomite or kaolin, 0.5 per cent. technical DDT on diatomite or kaolin. Rock phosphate, kaolin, or talc are not recommended. Where lindane or DDT are used in the dosages given, it is unlikely that the commodity will be tainted or rendered toxic to man or animals, even if no cleaning is undertaken.
Studies on the Bionomics of Aëdes aegypti (L.) in its Natural Habitats in a Coastal Region of Kenya
Authors: Teesdale C.
Published: July 2009

Studies have been made of the bionomics and ecology of Aëdes aegypti (L.) entirely under natural conditions and in its natural habitats on the Kenya coast.

Development from egg to adult under conditions approximating as nearly as possible to those in nature took a minimum of eight days and a maximum of twenty-five.

Males were in excess of females, in the proportion seventeen to ten, from eggs hatched in natural breeding places.

Although the mosquito may be able to propagate in houses, adults from outside habitually enter premises. If this entry is for egg-laying, then eradication by domestic larval control alone, although reputedly achieved elsewhere, is not possible under conditions obtaining in the coastal belt of Kenya. Windowtrap captures, however, indicate that the entry may not be for the purpose of egg-laying.

The seasonal reduction of both larvae and adults in houses during the hot, dry months of February and March is attributed to a combination of the absence of breeding places outside and the shorter life span of the mosquito at this time.

It is shown that both sexes enter and leave native huts throughout the 24-hour period, but the movement is confined almost wholly to the hours of daylight. The flight from houses is much reduced in the cool months (July and August). This corresponds with the season when most enter.
The hymenopterous parasitoids of eucalypt longicorn beetles,Phoracanthaspp. (Coleoptera: Cerambycidae) in Australia
Authors: Austin A. D. , Quicke D. L. J. , Marsh P. M.
Published: July 2009

The systematics of the hymenopterous parasitoids associated withPhoracanthaspp. in Australia are reviewed. An illustrated key to species is presented to facilitate their identification as part of ongoing attempts for the biological control ofP. semipunctata(Fabricius), an exotic pest on eucalypt trees. Information on the taxonomy, distribution and biology of 18 species of primary and hyperparasitoids associated withPhoracanthaspp. are presented. A new braconid genus,Jarra, is described to accommodate three new species,J. phoracantha, J. maculipennisandJ. bicolor, andDoryctes diadoxiNixon (Doryctinae), the latter associated with a buprestid host. Two other new species,Heterospilus nukunu(Doryctinae) andCallibracon moorei(Braconinae) are also described;Iphiaulax morleyiFroggatt is synonymized withAtanycolus tomentosusSzépligeti andI. rubricepsFroggatt is synonymized withSyngaster lepidusBrullé lectotypes are designated forI. morleyi, I. rubricepsandI. phoracanthaeFroggatt; andIpobracon fleviceps flaviceps(Cameron) andI. flaviceps mackayensisTurner are transferred toCallibracon. The encyrtid genusAventianellais recorded from Australia for the first time and the egg parasitoid ofP. semipunctata, A. longoiSiscaro described from Italy, is postulated to be endemic to Australia.
A biochemical and toxicological study of the role of insensitive acetylcholinesterase in organophosphorus resistantBemisia tabaci(Homoptera: Aleyrodidae) from Israel
Authors: Byrne Frank J. , Cahill Matthew , Denholm Ian , Devonshire Alan L.
Published: July 2009

Two acetylcholinesterase (AChE) variants, differing in sensitivity to inhibition by the organophosphorus (OP) insecticide paraoxon were identified in a population ofBemisia tabaci(Gennadius) from cotton in Israel using a single insect kinetic microplate assay. Two strains were established, homogeneous for one or other of the two variants, by isolating mated females from the field population onto individual cotton leaves, and testing a proportion of their female offspring to identify their AChE genotype. Polyacrylamide gel electrophoresis of their I-naphthyl butyrate hydrolyzing esterases showed that all insects contained esterase E0 14, which is indicative of B-type whiteflies, although the staining intensity of this band differed. Resistance to the OPs monocrotophos, profenofos and chlorpyrifos in leaf dip bioassays was consistent with the presence of the insensitive AChE. The data also indicated that separate mechanisms conferred resistance to the two pyrethroids cypermethrin and bifenthrin. The former, when used in a mixture with profenofos, was no more toxic than when the OP was used alone, and resistance to the mixture was largely dependent on the presence of the insensitive AChE.
Reproductive potential in the parasitoid Eupelmus orientalis (Hymenoptera: Eupelmidae)
Authors: Doury G. , Rojas-Rousse D.
Published: July 2009

Eupelmus orientalis (Crawford) (Hymenoptera: Eupelmidae) is a solitary ectoparasitoid of the larvae and pupae of West African bruchids. Since the biology of this species was unknown, studies were carried out on its reproductive biology. The age-dependent fecundity and offspring production of virgin and mated females of E. orientalis were determined under laboratory conditions at 33°C:23°C, 50%:80% r.h., L:D 12:12 on its host Callosobruchus maculatus (Fabricius) (Coleoptera: Bruchidae) during the first 15 days of the life cycle. No differences were found between virgin and mated females for any parameter. A study of the age-dependent fecundity and offspring production was also carried out under the same conditions over the entire life cycle of mated females. The resulting data were used to determine the longevity and reproductive potential of the species, particularly through the calculated life tables and estimation of the intrinsic rate of increase. With ten hosts per female per day, E. orientalis females had a mean longevity of 45.75±5.09 days. They laid an average of 219.91±39.08 eggs, parasitized 154.27±26.17 hosts, and produced 166.77±9.41 offspring, consisting of 80.46±14.10 males and 86.31±10.04 females. The total mean developmental time was 18.58±0.22 days for males and 20.03±0.21 days for females. The net reproductive rate (Ro) was 62.33 female progeny per adult female, and the intrinsic rate of population increase (rm) was 0.1389 per day. The generation time (G) was 29.76 days and the doubling time (DT) 4.99 days. These results constitute the first step to determine the potential of E. orientalis as an agent for the biological control of bruchidae, especially C. maculatus.
Inter- and intra-seasonal variation in outbreak distribution of the armyworm, Spodoptera exempta (Lepidoptera: Noctuidae), in eastern Africa
Authors: Tucker M. R.
Published: July 2009

Reports of the African armyworm, Spodoptera exempta (Walker), in eastern Africa for sixteen seasons (1972–73 to 1987–88) were analysed together with weather records to identify the most frequent locations of outbreaks and their relationships with weather. Outbreaks were classified into ‘primary’ outbreaks (derived from low density parent populations), ‘secondary’ outbreaks (derived from previous out breaks) and ‘critical’ outbreaks (leading to many subsequent outbreaks). Differences in seasonal severity of armyworm infestations in relation to the timing and location of primary outbreaks and early season rainfall were also examined. Trajectory analysis was used to estimate migrations of windborne moths, and the distribution of rainstorms was used to help estimate the timing of moth concentration leading to outbreaks of S. exempta. First reported armyworrn outbreaks from October to December in Kenya and Tanzania were usually primary. Critical primary outbreaks mostly occurred in east-central Tanzania, north-east Tanzania and the adjacent Taveta district of Kenya, and east-central Kenya. Strategic control (to prevent subsequent, downwind outbreaks) is best carried out in these areas. Migration direction was largely determined by seasonally dominant winds, although windfield disturbances were occasionally important. Three seasons in which very low numbers of S. exempta were reported, had heavy, persistent October to December rainfall leading to high larval mortality. Seasons with many outbreaks often had rainstorms separated by dry periods, during the rainy seasons.
The potential of some newer photostable pyrethroids to select for resistance in the housefly Musca domestica (Diptera: Muscidae)
Authors: Chapman P.A. , Webb D.P. , Walker S.J.
Published: July 2009

A strain of Musca domestica Linnaeus with low pyrethroid resistance was divided into four sub-strains, each was subjected to three selections in the laboratory with either alphacypermethrin, cypermethrin, deltamethrin or permethrin. Each selected strain was then tested for cross-resistance to the other pyrethroids and to synergized pyrethrins. Pyrethroid resistance was increased by all selecting agents by a factor of between 1.5 and 3.6 as measured at the KD50, thus demonstrating that the newer persistent pyrethroids had a similar potential to select for pyrethroid resistance as did permethrin. A field trial using a commercial alphacypermethrin formulation was carried out in an intensive animal unit against a population of M. domestica with a high pyrethroid resistance. After a high initial kill, the population rapidly recovered and a second application failed to control the population. Pre- and post-trial M. domestica samples were taken and resistance to alphacypermethrin and synergized pyrethrins was shown to have increased from 54.5 to 263.6 and 15.2 to 28.4 at the KD50, respectively.
A new Trissolcus Ashmead species (Hymenoptera: Scelionidae) from Pakistan: species description and its role as a biological control agent
Authors: Clarke Anthony R.
Published: July 2009

Trissolcus crypticus sp. n., a sibling species of T. basalis (Wollaston), is described. Introduced from Pakistan into Australia and Hawaii (via Australia) as a ‘strain’ of T. basalis, it was widely released for the biological control of Nezera viridula (Linnaeus). In Australia, the species reputedly gave widespread control of N. viridula populations in inland and northern areas. Examination of all available T. basalis specimens in Australia failed to discover any T. crypticus (other than voucher specimens) and its role as a biological agent warrants reassessment.
Migrating moths (Lepidoptera) collected in tower-mounted light traps in northern New South Wales, Australia: species composition and seasonal abundance
Authors: Gregg P. C. , Fitt G. P. , Coombs M. , Henderson G. S.
Published: July 2009

Light traps were operated between September and April for five years on towers on mountain tops at two locations in northern New South Wales, Australia. The traps were designed so that their lights could only be seen from above, and therefore only insects engaged in high altitude flight, presumed to be migrants, were captured. The catch consisted mostly of Noctuidae and Sphingidae. Sweep netting failed to reveal local breeding, and for many species there were few host plants close to the traps. A total of 51,580 moths were trapped at Point Lookout and 10,223 at Mt Dowe. Sphingids, mostly Hippotion scrofa (Boisduval), comprised 26.9% of the catch at Point Lookout, but only 2.6% at Mt Dowe, and there were more species of noctuids at Point Lookout (44) than at Mt Dowe (15). The most common noctuid species were Agrotis infusa (Boisduval), Mythimna convecta (Walker), Helicoverpa punctigera (Wallengren), H. armigera (Hübner), Dasygaster nephelistis Hampson and A. munda Walker. Known or suspected migrants comprised 94.6% of the catch at Point Lookout and 99.9% at Mt Dowe. However, there were at least 24 species not previously suspected as migrants. The seasonal distribution of catches varied between sites and years. Some species showed peaks in both spring and autumn in some years, but only in spring in other years. Many of the less common species were caught only in summer and autumn. Large catches were usually obtained overs short periods (1–2 nights), separated by long periods when catches were very low. These large catches, which were thought to represent major migrations, accounted for 76% of the catch in 3% of the trapping period at Point Lookout, and 87% of the catch in 2% of the trapping period at Mt Dowe.
The Influence of Drought upon Mosquito Life in Surrey
Authors: MacGregor Malcolm E.
Published: July 2009

The unusual and prolonged drought that we have experienced this year has had a marked effect upon the mosquitos. So much so, that while last year I found no difficulty in obtaining any of the eleven species which so far have been found to exist in this locality, yet for many weeks now it has been impossible to obtain any but a few Anopheles maculipennis (adults), Anopheles bifurcatus (larvae), Culicella morsitans (larvae, pupae, and adults), and Culex pipiens (larvae, pupae and adults).
Agrilus Foveicollis, Mars., as a Cause of the Decay of the Culture of Roses in Bulgaria
Authors: Mokrzecki S. A.
Published: July 2009

During the months of May and June 1921 I investigated the cause of the serious losses that had occurred among the rose-trees (especially Rosa damascena, Mill.) which are extensively grown in Bulgaria for making attar of roses. The conclusion arrived at is that the cause of the general decline in rose culture is inadequate nourishment of the plants, owing to an insufficient amount of humus and nitrogen in the soil, aggravated by the entire neglect of manuring by the growers. But the immediate cause of the death of thousands of rose-bushes has proved to be certain galls that are to be found on the stems, reaching 2–3 cm. in length and sometimes twice as thick as the normal stem.
Notes on a Colour Tropism of Asterochiton (A Leurodes) Vaporariorum, Westwood
Authors: Lloyd LL.
Published: July 2009

During 1919–20 an investigation into the habits of A sterochiton (Aleurodes) vaporariorum, Westw., was being carried out at the Lea Valley Experimental Station, Cheshunt, with a view to controlling its attacks on tomatoes under glass. The station exists for the study of scientific problems connected with the glasshouse industry, and as the staff is small, the work is necessarily confined to strictly economic lines. Points that appear in the course of the investigations cannot be followed to their ultimate conclusion in these earlier years of the station's existence if they seem to be of theoretical rather than of practical importance. The following notes relate to such a problem, which it has been decided to record, though in a very unfinished state.
Influence of gibberellic acid and nitrogen sprays on transmission of cabbage black ringspot virus by Myzus persicae (Sulz.)
Authors: Selman I. W. , Kandiah Umarany
Published: July 2009

Transmission of cabbage black ringspot virus to turnip plants by Myzus persicae (Sulz.) was reduced by foliar sprays of five parts per million gibberellic acid together with 0·2% ammonium nitrate, but not by each applied separately. The reduction occurred at 10°C but not 15, 20 or 25°C, and at a light intensity of 10 000 lux but not at 5 000 lux. The response was usually only evident towards the end of the normal range of the incubation periods, indicating that protection was probably only achieved when relatively small amounts of inoculum were introduced. The reduced transmission could not be related to aphid behaviour but changes were found in the free proline content and fine surface structure of treated leaves, and it is suggested that the results are to be interpreted in terms of changes in host cell metabolism.
Effects of sublethal doses of insecticides and of diet and crowding on Dysdercus fasciatus Sign. (Hem., Pyrrhocoridae)
Authors: Hodjat S. Hossein
Published: July 2009

The effects of sublethal doses of insecticides and unrelated environmental stresses on Dysdercus fasciatus Sign, were studied in the laboratory. Dieldrin applied topically to fifth-instar nymphs at 02–0·6 μg/individual increased egg production, at 0·8–60 μg/individual decreased egg production, and at 0·6–60 μg/individual decreased fertility. Applied to adults, dieldrin at 2–4 μg/individual reduced egg production, and at 0·02–0 08 μg/individual (males) and 0·2–0·8 μg/individual (females) shortened the life span. In a separate experiment, dieldrin at 0·2 μg/individual reduced egg production when applied to fourth-instar nymphs, but had no effect on fifth-instar nymphs or adults. p.p'DDT at 6 μg/individual applied topically to unmated females increased egg production. Exposure of all life stages to 0·06 mg DDT/ litre for two generations was followed by increased egg production and fertility: shorter exposure at 1 mg DDT/litre had no effect, and at 6–20 mg/litre egg production and fertility were reduced. Rearing on boiled cotton seed resulted in small adults with low gg production and fertility, the eggs being longer than normal. Crowding nymphs (24 individuals/200-ml cage) had the same effect on the size of the resultant adults. Starvation caused low egg production and fertility. Fluttering of males during a free fall (a measure of activity) was increased by crowding (maximum at 2 individuals/cage), by topically applied dieldrin at 0·04–0·08 μg/individual and DDT at 3–5 μg/individual, by two-generation exposure to 0·06 mg DDT/litre, but not by feeding on boiled cotton seed.
An evaluation of a genetic method for population suppression of Teleogryllus commodus (Wlk.) (Orth., Gryllidae) in Victoria
Authors: Hogan T. W.
Published: July 2009

Studies on the egg diapause of Teleogryllus commodus (Wlk.) in southern Victoria, and the effect of latitude on the intensity of diapause in Teleogryllids have led to the concept of population suppression by the genetic elimination of diapause. The method is based on the finding that males of the closely related T. oceanicus (Le Guillou) transmit the non-diapausing trait when crossed with T. commodus females. An additional suppressive factor is imposed by sterility in the progeny of the cross. An evaluation of the feasibility of this approach has been carried out in small-scale trials using field enclosures in which known populations of both types were studied. With a 10:1 ratio of non-diapausing/diapausing males, a mean of 73–8% of the eggs from the T. commodus females were hybrid, and with a 5:1 ratio 50–8%. The practical application of the method will not be attempted until the relative suitability of a number of candidate non-diapause biotypes has been determined.
Fertilisation, sex ratio and postembryonic stages of the citrus bud miteAceria sheldoni(Ewing) (Acarina, Eriophyidae)
Authors: Sternhcht M. , Goldenberg S.
Published: July 2009

A series of laboratory experiments was made on the citrus bud miteAceria sheldoni(Ewing). The postembryonic stages consist of larva, nymphochrysalis, nymph and imagochrysalis, each of which lasts 1–2 days, and imago, which lasts about two weeks. The nymphochrysalis and imagochrysalis are inactive pre-ecdysial stages, while the others are true active stages. The mite shows facultative arrhenotoky. Adult males deposit stalked spermatophores from which the sperm masses are taken up by virgin females. At 24–0°C fertilised females laid eggs that produced offspring consisting of 7–25% males. The males deposited 25–100 spermatophores (2–15 daily) during their adult life, with occasional interruptions. Spermatophores exposed for one hour to relatively extreme temperatures of < 5°C or > 38°C did not fertilise eggs. Mite populations from lemon trees usually comprised a low percentage of males in winter and a high percentage in spring and autumn.
Laboratory and field trials to determine the modes of action of malathion and diesel oil against Culicoides furens (Poey) (Dipt., Ceratopogonidae)
Authors: Davies John B.
Published: July 2009

One field and four laboratory trials were run to determine the reason for the success of 1–8% malathion in diesel oil in controlling Culicoides furens (Poey) in swamp mud in Jamaica. In the laboratory malathion and marine diesel oil (1:4000) was an effective larvicide for up to two days after application to the mud, but diesel oil alone gave only slight mortality even after six days. Judged by the emergence of adults, diesel oil gave 100% pupal mortality for five days and still showed some effect after four weeks; this effect was not improved by the addition of malathion. In the field, counts of emerging adults showed that diesel oil at 106–5 gal/acre gave 97–8% control of C. furens for up to eight weeks after application. It is concluded that, because of the possibility of pupicidal action, insecticides should be assessed on adult emergence rather than larval mortality.
Conditions for the experimental transmission of cabbage black ringspot virus by Myzus persicae (Sulz.) to turnip (Brassica rapa)
Authors: Kandiah Umarany , Selman I. W.
Published: July 2009

Experiments in a glasshouse have shown that the most favourable conditions for transmission of cabbage black ringspot virus by Myzus persicae (Sulz.) to turnip plants with two foliage leaves were as follows: an acquisition access period of five minutes; a test-feeding period of not less than two hours; the use of nine viruliferous aphids per test plant; the use of aphids from uncrowded colonies; the use of the third leaf from the base of an infected turnip (5-leaf stage) as virus source; and inoculation of the younget leaf of a test plant. Darkening plants for 24 or 48 h did not increase susceptibility to aphid inoculation, but increased it to mechanical inoculation in the summer. When the youngest leaf was inoculated, the age of the test plants (10-25 days after germination) did not influence transmission by aphid or mechanical inoculation.
On the Sex Ratio in Glossina
Authors: Squire F. A.
Published: July 2009

The preponderance of males in tsetse-fly catches is an interesting fact that has not been understood in the past. Attention is drawn to the importance of the agefactor. Teneral flies are nearly always taken in equal numbers whereas non-teneral A.G.I flies and A.G.2 flies have the highest male/female ratio. In A.G.3, the ratio drops, indicating a decline in reproductive capacity. Females become fugitive about seven days after emergence, at the time when the first egg is almost due to descend into the uterus, i.e., at the end of the teneral stage. This is the mating phase par excellence. Mating is prolonged, vigorous, and frequent, and this accounts for the early appearance of the mating scars. As the uterus lies under and between the mating cushions, it is unsafe for females with eggs in the uterus or young larvae to mate. Third-instar larvae are safer as the highly chitinized polypneustic lobes take the brunt of the pummelling from the claspers. Safe periods also occur during the hiatus between larvipositions when the uterus is empty. There are, of course, other factors influencing the ratio, but the age factor is considered paramount, and failure to recognize this in the past has resulted in a good deal of confusion.
Biology and Control of Labrador Black Flies (Diptera:Simuliidae)
Authors: Hocking B. , Richards W. R.
Published: July 2009

Twenty-five species of Simuliids are listed with indications of their relative abundance, importance as pests of man, seasonal appearance, temperature requirements, and larval habitats in Labrador. Seven of these are undescribed species. The most important species are Simulium venustum Say and Prosimulium hirtipes (Fries).

A circular area of 200 square miles around Goose Bay airport was surveyed for important breeding sites. Of 163 streams and rivers investigated, 77 were suitable as larval habitats, and larvae were virtually eliminated from them in June, 1950, by applications of a 10 per cent, solution of DDT in fuel oil at the rate of 1–5 p.p.m.- minutes from a helicopter, conventional aircraft, or boats, or by hand application from the ground. Methods of application are discussed.

The repopulation of the area by black flies was studied, and deductions are made concerning the flight habits of the most important species. On the basis of averages throughout the season, a great reduction in numbers of black flies at the centre of the area was obtained, and a worth-while reduction to a distance of between 4 and 6 miles from the centre. Even near the centre of the area, however, black flies were sometimes troublesome late in the season.

It is suggested that, where P. hirtipes is the important species, relief for at least one season could be secured by eliminating larvae within a radius of 2 miles; for S. venustum, 6 miles is suggested as a suitable radius. No adverse effects on useful animals were recorded.
Studies on Aqueous Suspensions of Insecticides. Part III. Factors affecting the Persistence of some Synthetic Insecticides
Authors: Hadaway A. B. , Barlow F.
Published: July 2009

Factors affecting the persistence of deposits from aqueous suspensions of insecticides have been studied.

There is an inverse relationship between particle size of insecticides and the initial contact toxicity to mosquitos. The influence of particle size on effectiveness decreases as the intrinsic toxicity of the insecticide increases. The compounds investigated can be arranged in order of immediate contact toxicity to mosquitos (Aëdes aegypti): dieldrin ≥ gamma-BHC > aldrin > DDT.
On some British Species of Ichneumon and Alomyia (Hym., Ichneumonidae)
Authors: Perkins J. F.
Published: July 2009

There has been considerable confusion in the determination of I. suspiciosus Wesmael. In fact, in Wesmael's series of this species in the Brussels Museum, the two species here differentiated were both represented. However, only one of these species agreed completely with his original description, and unfortunately this is not the species determined as suspiciosus by Thomson and by Roman. This latter form I regard as being a subspecies of I. septentrionalis Holmgren.
Tabanidae of the Island of Trinidad, B.W.I.
Authors: Bequaert J.
Published: July 2009

The present enumeration of the TABANIDAE known to occur in Trinidad is based almost entirely on specimens seen by myself, although I have included the very few published records apparently based on reliable identifications. None of the material was collected by me; but I am indebted for it to various museums and private collectors: Dr. J. G. Myers, Mr. D. Vesey-FitzGerald, Dr. Neal Weber, Mr. John Smart and Mr. H. Oldroyd (British Museum), Mr. L. L. Pechuman (Cornell University), and Dr. Alan Stone (U.S. Bureau of Entomology and Plant Quarantine).
New and little known species of Azotus Howard, Ablerus Howard and Physcus Howard (Hym., Aphelinidae) from Africa and Mauritius
Authors: Annecke D. P. , Insley H. Patricia
Published: July 2009

Descriptions are given of five new species of Azotus Howard from the Ethiopian region, including one from Mauritius. These bring the total number of Azotus species known from this region to eight. Two described species, A. capensis Howard and A. elegantulus Silvestri, are annotated and figured, and a key to the species is given. The related genus, Ablerus Howard, is recorded from Africa for the first time on the basis of a new species from the eastern Cape Province, and a new East African species of Physcus Howard, is described. A second East African species of the latter genus, one with flightless females, is characterised but not named to species.
Studies on the effect of the nutrient status of sugar-cane on the fecundity of Saccharosydne saccharivora (Westw.) (Hom., Delphacidae)
Authors: Metcalfe J. R.
Published: July 2009

An account is given of glasshouse experiments in Jamaica to determine the effects of agronomic practice on the fecundity of the sugar-cane pest Saccharosydne saccharivora (Westw.). Eggs (up to one egg per ovariole per day) develop throughout adult life. On young vigorous plant cane the pre-oviposition period was 5·3 days; egg production was highest during the first six days of the oviposition period and declined markedly after 12 days. Mean daily egg production per female over 12 days was taken as an index of fecundity.

The effects of fertiliser application (ammonium sulphate and potassium chloride), wet and dry water regimes, variety (B41227, B42231 and B4362) and crop cycle (plant and ratoon cane), all at different stages of crop development, were observed in four series of experiments involving 1 000 female S. saccharivora. Potassium (K2O) and phosphorus (P2O5) per cent lamina dry matter varied comparatively little, but nitrogen content declined with the age of the plant, increased with application of ammonium sulphate, and was unaffected by crop cycle or variety. Egg production was highest on young cane (up to a mean of 12·0 eggs per female per day), but declined on older cane; it increased with the application of ammonium sulphate but was unaffected by potassium chloride. A direct linear correlation between egg production and the nitrogen content of the leaf (r2 = 0·69, 0·81, 0·52 and 0·69 in series I–IV, respectively) suggested a causal relationship. The pre-oviposition period lengthened and the proportion of females failing to lay any eggs increased in the absence of fertiliser and with increasing plant age. Variation in leaf nitrogen under field conditions could affect egg production.
The performance of crosses between wild and laboratory-bred Glossina morsitans orientalis Vanderplank
Authors: Jordan A. M. , Nash T. A. M. , Trewern M. A.
Published: July 2009

A successful colony of Glossina morsitans orientalis Vanderplank was initiated at Langford in early 1967 with 94 females imported as pupae from Rhodesia. In September 1969, further pupae were received from Rhodesia. Experiments were undertaken in which the four possible combinations of crosses were made between males and females from the Langford colony and from the 1969 importation from Rhodesia. Females of Langford origin performed equally well irrespective of the origin of their mates and it is concluded that there is no evidence that the Langford colony of G. morsitans is either performing abnormally well, because of adaptation to the laboratory, or abnormally badly, because of adverse effects of inbreeding. The poorer performance of females of Rhodesian origin was manifested in poorer survival rather than a lower fecundity; it is attributed to adverse effects on these flies caused by handling of the pupae in the field and/or the stress of the journey from Rhodesia to Langford. It would seem that to avoid any risk of inbreeding in laboratory colonies, wild males only should be introduced periodically.
Field and laboratory studies on sexual attractiveness of females of Prays citri (Mill.) (Lep., Yponomeutidae)
Authors: Sternlicht M.
Published: July 2009

In laboratory experiments with Prays citri (Mill.) in Israel, females 1–16 h old proved more attractive to 2–6-day-old males than did female pupae 1–8 h before emergence or female adults 1–4-days old. Attractiveness in the field was tested by means of sticky traps baited with female pupae or adult females. Females were attractive for up to 14 days in summer (19–30°C) and 27 days in winter (8–20°C). Greatest attraction was shown by 1–7-day-old females during summer as compared with 5–9-day-old females during winter. Field experiments with baited sticky traps attached to wind vanes showed that more males were caught by traps aligned with the wind than by those placed at right-angles to it or hung among tree branches, by traps 1–7 m above ground than those 30–50 cm above, and by traps five metres distant from trees than those 10–80 m distant.
Some effects of temperature and larval food on the development of Spodoptera littoralis (Boisd.) (Lep., Noctuidae)
Authors: Baker C. R. B. , Miller G. W.
Published: July 2009

The development of all stages of Spodoptera littoralis (Boisd.) was studied in controlled-environment cabinets under a range of constant and cycling temperatures. Larvae were tested on three food plants; development was faster on lucerne than on two cultivars of chrysanthemum, Taffeta and Fred Shoesmith. The durations of each instar were similar in relation to larval life span, but at low temperatures and on chrysanthemum many larvae went through an extra instar. Late-instar larvae were nocturnal but larval development was little disturbed by a night-break lighting regime as used in the production of all-the-year-round (AYR) chrysanthemums, and only slightly more so by a reversed temperature cycle. The latter changed the daily pattern of moth emergence which otherwise occurred mostly when temperatures were highest or in the dark. The development results were used to estimate duration of development by summing (a) daily increments of development (100/duration of development), (b) day-degrees (for eggs 28·6 day°C above 14·8°C; for larvae on lucerne 266·1 day°C above 11·5°C, on chrysanthemum 257·1 day°C above 13°C, and above 13°C 177·1 day°C for male pupae and 153·5 day°C for female pupae). The estimates were compared with observed development times for all stages in an environment where temperatures fluctuated naturally. Both methods gave satisfactory estimates when development times were short, but temperature summation was less accurate when maximum temperatures fell close to base temperatures. It is concluded that summation of development increments would give a more consistently accurate account of the life-cycle of S. littoralis on AYR chrysanthemum under glass to enable development to be predicted or past events in the life-cycle to be dated. Tables of development increments against daily maximum and minimum temperatures are given for each stage. To estimate duration of development from these Tables, the daily percentage development corresponding to each day's maximum and minimum temperature is summed up to 100%. This gives an estimate of the median point of hatching or pupation.
Observations on the physiology of diapause and non-diapause larvae ofBusseola fusca(Fuller) (Lep., Noctuidae)
Authors: Usua E. J.
Published: July 2009

Experiments were done to compare respiration rate, thermal death point, weight loss and the life span of diapause and non-diapause larvae ofBusseola fusca(Fuller). The oxygen consumed by non-diapause larvae was 578–772 mm3/g/h while that by diapause larvae was 58–238 mm3/g/h. Thermal death points for both types of larvae were in the range 46·5–49·5 °C. At high and low relative humidities non-diapause larvae lost 4·4% and 16·3% of their weight, respectively, while diapause larvae lost only 1·0% and 7·0%. At 46° and 48°C the percentage weight loss by non-diapause larvae was about twice as much as that by diapause larvae. Life span was greater at a saturation deficit of 14·2–22·5 mm Hg in both types of larvae than either at 2·8–14·2 mm Hg or 22·5–28·0 mm Hg. At this range starving non-diapause larvae lived for 4·3–5·1 days and the diapause larvae for 7·7–8·7 days. The main factor enabling diapause larvae to survive adverse conditions appears to be their efficient water conservation mechanism.
Two new species of Exitianus Ball (Homoptera, Cicadelloidea, Euscelidae) related to E. turneri Ross, One Infesting Rice in Ghana
Authors: Ghauri M. S. K.
Published: July 2009

Exitianus occidentalis from rice in Ghana and E. centralis from Uganda and Congo, forming a subgroup with the hitherto unique species E. turneri Ross, are described as new. Comparative illustrations and notes are given for all three species.
The pupa and larva of Asphondylia gennadii (Diptera: Cecidomyiidae) and taxonomic implications
Authors: Gagné Raymond J. , Orphanides G. M.
Published: July 2009

Pupae and larvae from various recorded hosts of the cecidomyiid Asphondylia gennadii (Marchal), a pest of carob on Cyprus, are found to be anatomically similar. These are redescribed and illustrated. The species appears to be a Palaearctic generalist species analogous to the Nearctic Asphondylia websteri Felt. Asphondylia capsici Barnes (Syn. n.) is considered a new junior synonym of A. gennadii. An unnamed soybean pod gall midge in Japan appears also to be identical to A. gennadii.
Encarsiaparasitoids ofBemisia tabaci(Hymenoptera: Aphelinidae, Homoptera: Aleyrodidae): a preliminary guide to identification
Authors: Polaszek A. , Evans G.A. , Bennett F.D.
Published: July 2009

A key is provided for the recognition of previously describedEncarsiaspecies which are known to attack the tobacco whitefly,Bemisia tabaci(Genna-dius). 28 nominal species are included, of which type material has been examined for 22. Eight new synonymies are proposed:Encarsia aleyrodis(Mercet) andE. partenopeaMasi are both synonymized withE. inaron(Walker); E.bemi-siae(Ishii) is synonymized withE. transvena(Timberlake);E. citri(Ishii) is synonymized withE. strenua(Silvestri),E. angelicaHoward andE. desertiRivnay & Gerling are both synonymized withE. luteolaHoward;E. perspicuipennis(Girault) is synonymized withE. quaintancei(Howard);E. tabacivoraViggiani is synonymized withE. pergandiellaHoward.E. hispidaDe Santis is removed from synonymy withE. meritoriaGahan. A lectotype is designated forE. porteri(Mercet). The known distributions and alternative hosts ofEncarsiaspecies attackingB. tabaciare provided as well as references to biology and notes on their use in biological control.