bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observations on the control of the coffee berry borer, Hypothenemus hampei (Ferr.), with endosulfan in Uganda
Authors: Ingram W. R. 
Published: July 2009

Three field trials with endosulfan against coffee berry borer, Hypothenemus hampei (Ferr.), on both Coffea arabica and C. canephora are described. The insecticide was applied from motorized knapsack sprayers at 20 gal. per acre of an emulsified solution containing 0.2 per cent, active ingredient to the branches bearing the crop.In two trials endosulfan applied twice at 21-day intervals significantly reduced the numbers of cherries containing living borers and the percentage of damaged cherries at the first pick. In the third trial a single application of endosulfan proved to be as effective as the double one. Increases in yield could not be detected. It was shown, by allowing insects to emerge from caged samples of cherries taken when picking began, that endosulfan did not affect the host/parasite ratio of either H. hampei or Geratitis coffeae (Bez.), nor did it increase the numbers of berry-boring caterpillars.No off-flavours following treatment could be detected in liquoring trials of robusta coffee beans that were dry processed or pulped and washed.Laboratory experiments in which adults of H. hampei were exposed above, but out of contact with, filter papers that had been dipped in an emulsified solution containing 0·2 per cent, endosulfan showed that it was acting at least as a partial fumigant and was more effective at 30°C. than at room temperature (21°C); spraying should thus preferably be carried out on warm, sunny days. In view of these findings, and as it is relatively non-toxic, endosulfan is recommended for control of H. hampei in Uganda when heavy attacks occur.
Shot-hole borer (Xyleborus fornicatus Eichh.) of tea in Ceylon II.—The effect of chemical control on the yield and manurial response of tea
Authors: Cranham J. E. , Kanapathapillai P. , Kathiravetpillai A. 
Published: July 2009

In 1960–65, six field trials were carried out on tea estates in Ceylon to assess the effect on yield, and on the response of the crop to fertilizer, of dieldrin sprays applied after pruning to control shot-hole borer (Xyleborus fornicatus Eichh.). Periodic sampling was carried out to assess the numbers of borers and their galleries. Yields were recorded by weekly or fortnightly weighings of the green leaf plucked, over pruning cycles of two to four years.The pattern of the yield increases on the sprayed plots was related to the difference in attack between the sprayed and unsprayed plots. Increases were, in general, small in the first year and much larger in the second year, reaching peak values of 32–58 per cent. (on the yields of successive three-monthly periods recorded) in the late second year, and declining thereafter through the third year as the difference in attack declined. Over the first two years there were marked yield increases in eight of the nine pruning cycles, and these ranged from 11·7 per cent, to 26·3 per cent. There was significant regression (P<0·001) of the percentage increase in yield on the maximum difference in gallery counts. Yield increases in the third year of pruning cycles were also considerable and the results evidence a prolonged effect of the heavy borer attack occurring in the second year.In one trial there was a significant interaction between the effects of dieldrin spraying and of nitrogen supplied. Control of the borer greatly improved the crop response to nitrogen. Nitrogen application increased the yield but resulted also in a proportionately larger loss of crop from borer attack. There was a small but significant increase in the number of borer galleries on the plots receiving nitrogen.The evidence on the size and pattern of crop losses caused by the borer suggests that these occur both from shoot breakages and from the direct effect of galleries on the growth of stems.The significance of the results in relation to estate practice, and the economics of spraying, are briefly discussed.
Field Trials of the Control of Glossina palpalis (R.-D.) by Obstructive Clearing
Authors: Kernaghan R. J. , Davies J. B. 
Published: July 2009

Two field trials of obstruction (‘ obstructive clearing ’) as a means of control of Glossina palpalis (R.-D.) in locations representative of the Northern and Southern Guinea Savannah zones of Nigeria, are described.In neither case was complete eradication achieved, pockets of G. palpalis remaining from the beginning at certain points on the main stream. Greater success was obtained in the smaller tributaries, which lent themselves more to obstruction. There was little penetration of G. palpalis for any great distance into obstructed reaches from natural ‘ reservoirs ’ left abutting on to the obstruction, but a trial of the ‘ protective ’ value of obstruction failed, owing to complete penetration in some strength of 300 yd. of obstructed stream on either side of the point to be protected. In neither case was immigration of flies from elsewhere into the trial areas an important factor. Although, at first, the surviving fly population was very localised, there were later indications that dispersal was beginning to take place.Some accidents which may happen to obstruction are described, with their effects on its ultimate appearance. Consequent to these, a number of factors which limit the wide application of obstruction are stated. The more important of these are: the dimensions of the river-bed, which may be too large to permit of successful obstruction; the presence of wide swampy forest through which G. palpalis ranges freely; alternatively, the presence of shallow rocky stretches with low eroded banks that may be devoid of all but certain characteristic trees, where adequate obstruction is impossible; the rate of run-off of water in the catchment area, rapid run-off leading to spates which disrupt the obstruction; human interference with the obstruction in quest of firewood.No technical difficulties were encountered in carrying out obstruction, and costs were from 40 to 50 per cent, cheaper than comparable partial clearing.Considering the subsequent appearance of originally obstructed stream, and its frequent resemblance to partial clearing, the suggestion of ‘ destructive ’ clearing is put forward, in which the top canopy would be destroyed, but no effort made either to create obstruction or to clear away the fallen trees. Instead, reliance would be placed on the action of the various agencies encountered in these trials, which brought about the disruption of the obstruction, to produce the desired end-result.It is concluded that successful obstruction depends too much on specialised conditions, difficult to fulfil in large-scale tsetse control schemes, and that it is unlikely to become a normal method of control of G. palpalis in the savannah zones of Nigeria.
Investigations on Heliothis armigera (HB.) in Uganda
Authors: Coaker T. H. 
Published: July 2009

A survey of the populations of eggs and larvae of Heliothis armigera (Hb.) was made on the Cotton Research Station, Namulonge, in Buganda Province, Uganda, over the four-year period, 1954–57 inclusive, on cotton, maize, groundnuts, beans and, in one year, sunflower. The populations encountered were low in comparison with some other cotton areas in Africa. The oviposition rate on each crop closely followed the flowering cycle, and there was no indication of the population from one crop influencing that on a subsequent crop, even when their flowering cycles overlapped. Under the normal crop sequence there is a sufficient gap between the attractive phases of successive crops to cause dispersal, possibly to wild host-plants, of the moths emerging from pupae bred in the preceding crop.The variation in population from year to year on a given crop was no greater than that between different localities in any one season. Maize and sunflower did not prove successful when tested as trap crops grown adjacent to cotton.Earias spp. and Argyroploce leucotreta Meyr. were less abundant than Heliothis and together constituted only 27 per cent, of the total population of Lepidopterous larvae on cotton.A method is described for breeding H. armigera, in the laboratory, in which the mean duration of the various stages was: egg, 4 days; larva, 24·8 days; pupa, 22·9 days; preoviposition period, 3·1 days; and oviposition period, 10·4 days. The mean number of eggs laid per female was 751·6, of which 71·4 per cent, hatched. Larval diets consisting of differing species and parts of food-plants caused significant differences in larval and pupal periods, the former being least (21·8 days) on maize silks and greatest (33·6 days) on sunflower corolla and receptacle, and the latter least (19·7 days) after larval feeding on three-week-old maize cobs and greatest (26 days) after seven-week-old cotton bolls. Pupae developing from larvae collected from the field did not exhibit any diapause or resting stage.Two egg parasites and 15 larval parasites (three of which were probably secondary) were bred from material of H. armigera collected in the field, but the degree of parasitism remained low throughout the year. A nuclear polyhedral virus disease of the larvae was also recorded.It is concluded that under the climatic conditions encountered, H. armigera is active throughout the year because wild or cultivated food-plants are always available and no resting stage of the insect is induced; this continuous activity is accompanied by biologically controlling factors that maintain populations stable at a relatively low level.
Immature Nutfall of Coconuts in the Solomon Islands III.—Notes on the Life-history and Biology of Amblypelta
Authors: Brown E. S. 
Published: July 2009

Observations on the population density of Amblypelta cocophaga China on coconut palms in the Solomon Islands are described. Although the figures are somewhat larger than those previously reported for the related Coreid, Pseudotheraptus wayi Brown, in Zanzibar, the densities are still very low.Observations were made on the oviposition habits of A. cocophaga. The principal oviposition site, contrary to previous observations, was found to be on the undersides of the fronds, in the basal recesses of the leaflets. The first-instar nymphs on hatching have to make their way to the spadices in the centre of the palm crown; this explains why first-instar nymphs are themselves only rarely found on the spadices, and also why a single treatment with insecticide is not completely effective, since the oviposition sites escape the treatment. Observations on the number of eggs on coconut palms are recorded.Anastatus axiagasti Ferrière was found to be a common egg-parasite of Amblypelta cocophaga in certain plantations of Guadalcanal. Rates of parasitisation on coconut palms ranged from 15·5 to 55 per cent, with an average of 33·3 per cent. The percentage of successful hatching of Amblypelta eggs ranged from 19 to 38 per cent., with an average of 31·3 per cent.Investigation of the area of Baunani plantation in Malaita, where the Tachinid parasite, Trichopoda pennipes (F.), had been released in 1949, indicated that it has not survived there, or, if it has, is exercising no control over A. cocophaga.Observations are recorded on two predators of interest with regard to immature nutfall.
The responses of stomoxys spp. (Diptera: Muscidae) to traps and artificial host odours in the field
Authors: Holloway M. T. P. , Phelps R. J. 
Published: July 2009

AbstractIn Zimbabwe, cotton cloth dyed phthalogen blue attracted three times more Stomoxys spp. than Alsynite fibreglass panels. A single F3 trap caught nearly six times as many Stomoxys spp. as four Williams traps. The host odour component l-octen-3-ol (released at 0.6 mg/h) increased catches of Stomoxys spp. in an F3 trap (P < 0.05), but 4-methylphenol (0.7 mg/h) and 3-n-propylphenol (0.15 mg/h) did not (P > 0.05). Insecticide-impregnated targets did not appear to control a population of Stomoxys spp. attacking cattle. However, it is concluded that there is scope for the improvement of trapping and control systems for use against Stomoxys spp.
Monitoring human-biting mosquitoes (Diptera: Culicidae) in Tanzania with light-traps hung beside mosquito nets
Authors: Lines J.D. , Curtis C.F. , Wilkes T.J. , Njunwa K.J. 
Published: July 2009

AbstractMosquitoes were caught in bedrooms in Tanzanian villages by human-biting catches and in light-traps set close to occupied untreated bed nets. Catches by each method were carried out on pairs of nights in the same week at different seasons and in different villages. The pairs of adjacent catches by the different methods showed a strong correlation. Analysis of the ratio between the catches by the two methods on pairs of nights in the same week indicated that on average three light-traps caught about the same number of mosquitoes as a team of two human catchers. The ratio did not differ significantly between Anopheles gambiae Giles (sensu lato), A. funestus Giles, and Culex quinquefasciatus Say, nor between the villages, or between times when mosquito populations were high or low. The distribution of numbers of ovarian dilatations differed significantly between catches in different villages and seasons but not between pairs of catches by the two methods. Similarly, the parity and sporozoite rates agreed between pairs of light-trap and house-resting catches, but differed markedly between villages and seasons. Thus it is concluded that light-traps used in conjunction with bed nets catch a representative sample of the vectors which would have bitten humans in bedrooms in this area.
Activity of Chilo partellus (Lepidoptera: Pyralidae): eclosion, mating and oviposition time
Authors: Päts Peeter 
Published: July 2009

AbstractThe majority of Chilo partellus (Swinhoe) males emerge within the first two hours of scotophase (20.00 to 08.00 h), females five hours later. The asynchrony of eclosion times facilitates mating during the last five hours of scotophase on the night of eclosion. Oviposition occurs during the first six hours of scotophase the following night but the majority of the eggs are deposited during the first two hours. No eggs are laid during photophase. A device for recording the timing of oviposition is described. Previous work is reviewed.
Egg parasitism in Aphelinidae (Hymenoptera: Chalcidoidea) with special reference to Centrodora and Encarsia species
Authors: Polaszek Andrew 
Published: July 2009

AbstractAphelinidae are all insect parasitoids, and most species are associated with nymphal stages of Homoptera: Sternorrhyncha, either as primary parasitoids or hyperparasitoids. The occurrence of egg parasitism in aphelinids has been recorded in eight of the 38 valid genera and these records are reviewed; it is particularly common in the genus Centrodora, which is shown to be the most polyphagous in the family. One species, C. darwini (Girault), is given special attention because of its occurrence in three recent surveys for biological control agents of crop pests. It is briefly redescribed, diagnosed, and shown to be the most polyphagous aphelinid known. A checklist of Australian Centrodora spp. is given, including the new combination Centrodora grotiusi (Girault) comb. n. The purported evidence for the classification of certain Encarsia spp. associated with eggs of Lepidoptera as ‘heterotrophic parasitoids’ is re-examined and dismissed.
The Chemical Control of the Wattle Bagworm, Kotochalia junodi (Heyl.), by Aerial Spraying. II.—The Use of Toxaphene and Endrin in the earlier Stages of an Infestation
Authors: Ossowski L. L. J. 
Published: July 2009

SummaryReplicated sample plots of wattle (Acacia) were sprayed from the air with 2 oz. endrin and 1½, 2¼, 3 and 6 lb. toxaphene per acre, each in light diesel oil, to test the effect of these insecticides on the bagworm, Kotochalia junodi (Heyl.), and other wattle fauna. All invertebrates which fell from the sample trees were collected on sheets at intervals after spraying and identified. The mortality of bagworms was assessed after 10 to 14 days.The mean corrected mortality was significantly lower in the treatment with 1½ lb. toxaphene than in the others, which, however, did not differ significantly amongst themselves. In all cases the kill was greater in the upper than in the lower parts of the tree crowns. There was no difference in the final percentage “fall-off” of bagworms in all plots, though in those treated with endrin the initial rate was higher. A very high kill, ranging from 96·6 to 98·5 per cent., was obtained in all but the 1½ lb. toxaphene plots, but even the 6 lb. application was not sufficient to reduce the bagworm population to its endemic level.The arthropods, other than bagworms, collected on ground sheets are listed by Orders and Families and also classified into groups as beneficial, indifferent, and harmful. Nearly two-thirds of the total were found to be beneficial.
Preliminary Note on a Method for the Direct Estimation of Populations of Pseudotheraptus wayi Brown on Coconut Palms
Authors: Yeo D. , Foster R. 
Published: July 2009

A technique is described for counting the numbers of Pseudotheraptus wayi Brown on coconut palms, on which this Coreid is a serious pest in East Africa, Zanzibar and the neighbouring islands. The crown of each palm is systematically searched by an African assistant, the insects collected being classified by instars and then replaced. The adults can fly and very few are seen or captured.Palms were examined by a team of searchers in five areas in a well-maintained plantation on Mafia Island, 3–4 separate samples, each of 61–138 palms, being taken in each area between mid-January and mid-February 1956. In all, 13 searchers participated, but not all were used on the same day; when they had become experienced their daily catches were of comparable size.The total nymphal populations, and the proportions of them in the various stages, are sufficiently consistent to suggest that the searching technique may give reproducible results, and thus be of considerable value as a means of assessing the results of control measures.The average catch was about one nymph for each palm that was searched, and recaptures from known numbers of bugs liberated indicated that about one quarter of the population present was being found. The nymphal population is not distributed at random among the palms.
Observations on the Behaviour of some Mosquitos of the Kenya Coast
Authors: Van Someren E. C. C. , Heisch R. B. , Furlong M. 
Published: July 2009

The mosquitos of two villages on the Kenya coast were studied over a period of two and a half years, which included years of very light, average and very heavy rainfall. A survey was made of the species occurring in the bush and in the houses, and in addition 24-hour biting catches were done and window-trap catches were examined to obtain information on the movement of species in and out of houses.Sixty five species were taken in net catches in the bush but only 19 were taken regularly; five (Taeniorhynchus uniformis (Theo.) and T. africanus (Theo.), Aëdes woodi Edw., Culex invidiosus Theo. and C. guiarti Blanch.) were abundant. In the houses, two species, C. pipiens fatigans Wied. and Aë. aegypti occurred regularly, the former being abundant and the latter not uncommon. Anopheles gambiae Giles and A. funestus Giles were seasonal; A. funestus appeared only after exceptionally heavy rain. The in-going window trap attracted only an occasional mosquito seeking shelter during the day and only six species were taken. Thirty species were found in the out-going trap but only seven occurred regularly. A. gambiae, A. funestus, T. uniformis, T. africanus and C. p. fatigans were most active during the hours of darkness, with the main activity in the four hours before dawn. Aë. aegypti had two waves of activity, in the four-hour periods before dawn and before sunset, respectively; the sunset peak was higher and the main activity probably occurred between 18 and 19 hr., as previously recorded for this species in Mombasa.Thirty five species were taken biting in the 24-hour catches in situations designated bush, house and compound, respectively. The biting cycles of A. gambiae, Aë. aegypti and C. p. fatigans have been compared in the three situations. The biting rhythm of each species was much the same in the different environments but the time and magnitude of the main peaks varied. In the case of Aë. aegypti, which probably includes two different forms, there is a marked difference in the magnitude of the evening peak in the bush and house. The biting cycles in the bush are given for A. squamosus Theo., T. uniformis, T. africanus, Aë. fryeri, Aë. metallicus (Edw.), Aë. albicosta (Edw.) and C. antennatus (Becker) and their occurrence in the other two situations is noted. The cycles of T. uniformis and Aë. fryeri agree with previous findings, but that of T. africanus differs from other cycles recorded for this species by having the main biting after midnight. The remaining species were rare, but one catch of 274 specimens of A. funestus was recorded.Resting mosquitos were more numerous in the second half of the year from August to December, a period of light rainfall and high temperatures. Biting mosquitos were more commonly taken, especially in the bush, in the second quarter of the year, during the main rainy season. The biting activity of some species increased in the houses in the second half of the year, when there are high winds, and biting in the bush was minimal.
Selection for a moderately insecticide resistant clone of Myzus persicae (Hemiptera: Aphididae) on sugarbeet in the absence of pesticides
Authors: Williams I.S. , Haylock L.A. , Dewar A.M. , Dixon A.F.G. 
Published: July 2009

AbstractHighly resistant and extremely resistant clones (R2 and R3) of Myzus persicae (Sulzer) exhibited a significantly lower mortality and developed a deleterious dark stomach deposit less frequently on sugarbeet than a susceptible (S) clone. After allowing equal populations of four resistant clones to develop together on sugarbeet for four weeks, approximately half of the aphids recovered were from the moderately resistant (R1) clone, suggesting that this clone had a significantly greater reproductive rate than the others. There was no significant difference in the propensity of any clone to produce alates on sugarbeet, although none of the clones produced very many. It is suggested that, even in the absence of insecticides on sugarbeet, resistant clones may become dominant due to their higher fecundity (R1 clones) and lower mortality (R2 and R3 clones) than susceptible clones.
Fungous Diseases of Lamellicorn Larvae in Southern Rhodesia
Authors: Bünzli G. H. , Büttiker W. W. 
Published: July 2009

One exceptional instance of a mycosis, with epidemic character, in white grubs has been studied in Southern Rhodesia.The hosts were the larvae ofAnomala exitialisPér. andSchizonycha profugaPér., which are tobacco pests, the entomophagous fungi beingTorrubiellasp. (most prevalent),Beauveria bassiana(Bals.) Vuill. andMetarrhizium anisopliae(Metsch.) Sorokin.Soil with an abnormally high content of nitrogenous organic matter favours the breeding of the two insects but at the same time provides a suitable medium for the survival and development of a high degree of virulence in the cryptogamic pathogens.