bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal abundance, diel biting activity and parity of Aedes polynesiensis marks and A. samoanus (Grünberg) (Diptera: Culicidae) in Samoa
Authors: Samarawickrema W. A. , Sone Fola , Cummings R. F.
Published: July 2009

The seasonal abundance, biting cycle, age composition and survival of females of Aedes polynesiensis Marks and A. samoanus (Grünberg), the major vectors of subperiodic bancroftian filariasis, were studied in Samoa. A. polynesiensis density was low during the high rainfall months and increased immediately following them. A. samoanus density showed no clear relation to rainfall. A. polynesiensis was active throughout the day, with peaks indoors and out at 08.00–09.00 h and 16.00–18.00 h. The nulliparous and parous populations showed similar patterns of activity. The biting cycles of 2-parous and 3- plus 4-parous females were asymmetric with time. A. samoanus was active throughout the night, with highest activity at 23.00– 01.00 h. A minor peak at 19.00–20.00 h was more pronounced among older females than among younger ones. Night biting by A. polynesiensis and day biting by A. samoanus were rare. The parous proportion of A. polynesiensis ranged from 36·3 to 59·5% and the epidemiologically significant 3- plus 4-parous proportion ranged from 1·0 to 6·7%. The parous proportion of A. samoanus was 37·9–49·7% and the 3- plus 4-parous proportion 1·4–2·6%. The proportions found to be parous in both vectors were generally higher in the cool than the warm season, suggesting higher daily survival during that period.
Insecticide tolerance of pregnant females of Glossina palpalis palpalis (Robineau-Desvoidy) (Diptera: Glossinidae)
Authors: Riordan E. K.
Published: July 2009

Females of Glossina palpalis palpalis (Robineau-Desvoidy) caught in Nigeria were treated topically with acetone or different doses of insecticides. None was fed after treatment. Flies later larvipositing were considered to have been pregnant and those neither aborting nor larvipositing as nonpregnant. Pregnant flies were 1·3 times as heavy as non-pregnant ones. Relative tolerances were assessed by comparing LD50s. For organochlorines (DDT, dieldrin and endosulfan), pregnant females were 2·5—4 times as tolerant as non-pregnant ones, doubtless due to diversion of insecticideinto lipid-rich larval food during late pregnancy. Data for pregnant flies did not indicate any increased tolerance of organophosphates (malathion, fenitrothion, tetrachlorvinphos and pirimiphos-methyl), possibly due to the low lipid solubility of these insecticides.Pregnant and non-pregnant females were equally tolerant of the pyrethroid Sumithrin ((lR)-cis-trans-isomer of phenothrin); accelerated larviposition prevented diversion of insecticide into in utero larvae. Pregnant females were 2·6 times as tolerant of tetramethrin (pyrethroid) as non-pregnant ones. Twenty-five per cent, of flies treated with acetone or low insecticide-doses larviposited, but the results indicated that larviposition was inhibited by high doses of most insecticides, which killed before larviposition, and, noticeably, by intermediate doses of some pyrethroids (fenvalerate, permethrin and deltamethrin), probably causing prolonged paralysis of uterine and larval muscles. The results did not indicate there was raised tolerance of fenvalerate, permethrin or deltamethrin among pregnant females, but calculations including assumed pregnant ones (unrecognized due to inhibited larvipositions) suggested that pregnant females were 2·5–5·5 times as tolerantas non-pregnant ones. Other investigations showed that flies surviving for several days after treatment with pyrethroids can feed and thrive; if this allows time for the reversalof delayed larviposition, then pregnant females could be significantly more tolerant of some pyrethroids than non-pregnant ones.
Effects of the malathion-bait mixture used on citrus to control Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) on the Florida red scale, Chrysomphalus aonidum (L.) (Hemiptera: Diaspididae), and its parasitoid Aphytis holoxanthus DeBach (Hymenoptera: Aphelinidae)
Authors: Cohen Ephraim , Podoler Haggai , El-Hamlauwi Muhamad
Published: July 2009

Examples of Chrysomphalus aonidum (L.) from which the scale covers had been removed, were about six times as sensitive to malathion as intact insects (LC50s of 0·09% and 0·55%, respectively). These results indicate that the scale cover probably absorbed part of the insecticide. Immature stages of the external parasitoid Aphytis holoxanthus DeBach on C. aonidum were not affected by 0·13% malathion applied to the host. However, adults of the parasitoid, which were extremely susceptible, were exposed before or during emergence to lethal levels of the insecticide present in the host scale cover. The findings are discussed in the light of the adverse effects of malathion-bait sprays applied against Ceratitis capitata (Wiedemann) on beneficial insects, and failures of biological control of scale pests on citrus in Israel.
The population ecology of Glossina pallidipes Austen (Diptera: Glossinidae) in the Lambwe Valley, Kenya. I. Feeding behaviour and activity patterns
Authors: Turner D. A.
Published: July 2009

Investigations into feeding behaviour and activity patterns, basically by biconical trap sampling, were carried out as part of a study of the population ecology and dynamics of Glossina pallidipes Austen in the Lambwe Valley, Kenya. Host-preference determinations from blood-meal analyses showed that over 80% of feeds constantly derived from bushbuck, buffalo and bushpig, in roughly equal proportions. Activity cycles in relation to feeding and pregnancy, investigated by mark-release-recapture and physiological methods, indicated four-day feeding intervals for males and three-day ones for females. The periodicity was more variable in males, and in females was contingent upon reproductive events, with feeding mainly taking place just before the in-utero moult of the second-instar larva to the third instar, just after larviposition and again at a more variable time during pregnancy. Comparisons of nutritional status from size, weight, and fat and haematin levels showed that flies from thicket had consistently greater fat reserves than flies from Acacia woodland and conifer plantation. No seasonal differences were found, nor any relationships between other variables. Based on hourly sample data, both sexes showed unimodal diel activity patterns, but with clear differences. Activity was most closely correlated with temperature, to a lesser extent with saturation deficit and least with light intensity, and better correlations were obtained with females than males. Diel activity patterns in both sexes were also age-related, and from the close similarity found between male and virgin female activity patterns it was inferred that male activity around traps was partly sexually oriented. Using electric screens in conjunction with biconical traps, comparisons between flies attracted to traps and those actually caught showed that traps were relatively more efficient in catching males than females, but captures were representative of the active population in terms of age and pregnancy.
Protein requirements for oogenesis in the Australian bush fly, Musca vetustissima Walker (Diptera: Muscidae)
Authors: Hayles L. , Matthiessen J. N.
Published: July 2009

Females of Musca vetustissima Walker in the first ovarian cycle and of a wide range of body size were fed a range of measured quantities of protein-rich liver exudate. For a given amount of exudate, a greater proportion of large flies than of small ones matured oocytes; for a given size of fly, the proportion that matured oocytes increased with the amount of exudate ingested. Additionally, large flies matured more oocytes on less exudate than did small flies, which had fewer ovarioles.
Effect of temperature on the toxicity of S-bioallethrin andcypermethrin to susceptible and kdr-resistant strains of Blattella germanica (L.) (Dictyoptera: Blattellidae)
Authors: Scott Jeffrey G.
Published: July 2009

The toxicity of two pyrethroid insecticides, S-bioallethrin and cypermethrin, was investigated over time at 12, 25 and 31°C in susceptible and kdr resistant strains of Blattella germanica (L.). Both strains showed a negative temperature coefficient (i.e., greater kill with decreasing temperature) for S-bioallethrin. The susceptible strain had a negative temperature coefficient for knockdown, but a positive temperature coefficient for mortality towards cypermethrin. The resistant strain had a negative temperature coefficient towards cypermethrin at all times. Resistance to S-bioallethrin was generally greatest at 25°C initially, although the difference between temperatures and the level of resistance diminished with time. Resistance to cypermethrin was significantly less at 12°C than at 25 or 31°C.
Dispersion patterns and sequential sampling plans for Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae) in cowpeas
Authors: Salifu A. B. , Hodgson C. J.
Published: July 2009

The within-plant dispersion characteristics of Megalurothrips sjostedti (Trybom) on cowpeas were determined in studies in Nigeria. Iwao's regression procedure and Taylor's power law analysis were used to determine the relationship between the mean and variance of thrips counts. Both methods showed that adult thrips were randomly distributed within cowpea plants at initial low populations. At later high densities, Iwao's method provided a better fit of the population dispersion of larvae and adults and showed that both were aggregated. The negative binomial best described this aggregation at high population densities. Sequential count plans suitable for pest management surveys were developed using critical stop lines derived from Iwao's regression procedure and Taylor's power law, but the latter was found to require less effort to achieve the same level of precision. There was a functional relationship between the variance and mean of untransformed population counts, and the suitability of transformation functions is discussed.
Evaluation of sampling methods for Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae) on cowpea
Authors: Salifu A. B. , Singh S. R.
Published: July 2009

Five sampling methods were evaluated for efficiency in estimating field populations of Megalurothrips sjostedti (Trybom) on cowpeas in Nigeria. The methods (sticky traps, water traps, sweep netting, shaking plants and the collection of whole plant samples) were judged on the basis of low sample variance, low cost and fidelity to absolute population trends. Shaking plants and water traps were the best sampling techniques on the basis of sample variance and cost. Shaking plants also showed the closest correlation with absolute population trends and is therefore recommended for rapid estimation of field populations of thrips. The performance of the usual alcohol method of sampling M. sjostedti on cowpeas (collecting racemes and flowers in alcohol) was not comparable with those of shaking plants and water traps, but was considered important because it sampled the infested structures, eliminating more transient visitors which might also be sampled by shaking plants.
The orientation of males of Glossina morsitans morsitans Westwood (Diptera: Glossinidae) to pheromone-baited decoy ‘females’ in the field
Authors: Hall Martin J. R.
Published: July 2009

Field studies in Zimbabwe of the orientation of males of Glossina morsitans morsitans Westwood to decoy ‘females’ (9 × 3-mm rectangles of 2-mm thick brushed nylon, baited with sex pheromone, 15,19,23-trimethyl-heptatriacontane, and placed on a vertical, 1-m2 black cloth screen) demonstrated that (1) no olfactory response to air-borne pheromone was involved in the orientation of males to decoys, (2) the presence of decoys on a stationary screen did not increase the numbers of males landing on the screen, but they directed landings onto the decoys or the adjacent screen surface, (3) males did not differentiate between black or brown decoys, (4) males were more attracted to vertically oriented decoys on the screen surface than to decoys held away from the surface, and (5) males were more attracted to decoys at the centre of the screen than to decoys near the top or bottom edges. Points 1, 2 and 4 also applied in the case of G. pallidipes Austen using decoys dosed with its pheromone (13,23-dimethylpentatriacontane), but this species preferred black to brown decoys and showed less overt sexual activity than G. m. morsitans. Males of G. m. morsitans each removed 1–2μg of pheromone by contact with a decoy, leading to a gradual loss of the decoy's stimulatory power.
Survival of female bush flies, Musca vetustissima Walker (Diptera: Muscidae), in relation to reproductive age
Authors: Vogt W. G.
Published: July 2009

Survival rates of females of Musca vetustissima Walker were estimated as a function of their reproductive age, based on age-distributions of field females whose headwidths ranged from 1·5 to 2·5 mm. Females had a mean life expectancy of 140 day-degrees above 8°C, which was independent of fly size. They did not respond to baited traps during the first 15 day-degrees C of adult life. Thereafter, trappability varied with reproductive age but was affected by fly size only during the initial stage of the first ovarian cycle. Because ovarian development rates and female fecundity are dependent on fly size, the expected numbers of eggs laid by field females 1·5–2·5 mm in headwidth during their lifetime range from 28 to 106.
The dynamics of the adult population of Heliothis armigera (Hübner) (Lepidoptera: Noctuidae) within the Sudan Gezira in relation to cropping pattern and pest control on cotton
Authors: Topper Clive P.
Published: July 2009

A method is presented for quantifying moth area densities in individual crops and average densities over the total crop area. Mortality within the total Heliothis armigera (Hübner) adult population as a result of insecticide applications against larvae on cotton in the Sudan Gezira was found to be very substantial for males and virgin and inseminated females. The level of adult mortality which was previously unknown, was shown to be an important factor in Heliothis control. The relative importance of alternative host crops as source sites of adults which infest cotton was demonstrated. Initially, larval populations built up in groundnut fields between July and early September. Females emerging from groundnut fields colonized sorghum in late August and early September and cotton slightly later. Larval densities found in groundnut and sorghum fields correlated strongly with the average densities of virgin females found 12 days later. Groundnuts provided the most important source of adults. The virgin female population was in turn highly correlated with the remainder of the adult population (males and inseminated females), demonstrating that H. armigera adults attacking cotton within the Gezira are locally produced. Adults were attracted to sorghum in large numbers for feeding and oviposition, but survival there of older larvae (fourth to sixth instars) to the adult stage was only 25% of that in groundnuts. The implications for pest management are discussed.
A survey for resistance to acaricides in cattle ticks (Acari: Ixodidae) in three major traditional cattle areas in Zambia
Authors: Luguru S. M. , Chizyuka H. G. B. , Musisi F. L.
Published: July 2009

A survey for resistance to acaricides in Rhipicephalus appendiculatus Neumann, Amblyomma variegatum (F.), Boophilus decoloratus (Koch) and B. microplus (Canestrini) was carried out in three important cattle areas of Zambia during three consecutive rainy seasons (November-May) from 1981–82 to 1983–84 to determine the pattern and distribution of resistance to dieldrin, dimethoate, dioxathion and chlorfenvinphos. Resistance was assessed using the FAO resistance test kit. Resistance to dieldrin, dimethoate and dioxathion was found in a greater number of samples from Central and Southern Provinces than from Northern and Eastern Provinces. Relatively high resistance factors were recorded for R. appendiculatus against dimethoate (mean resistance factor (RF) 10·7 ± 3·8×) and dioxathion (mean RF 8·6 ± 1·9×). B. decoloratus from Central and Southern Provinces showed mixed responses to dieldrin and low resistance to dimethoate (mean RF 4·1 ± 2·3×) and dioxathion (6·4 ± 5·0×). Most samples of A. variegatum and B. microplus were susceptible to the four acaricides. Generally, most of the ticks tested showed high susceptibility to chlorfenvinphos.
Resistance of melon to the carmine spider mite,Tetranychus cinnabarinus(Boisduval) (Acari: Tetranychidae)
Authors: Mansour F. , Karchi Z. , Omari N.
Published: July 2009

The resistance of 32 melon lines toTetranychus cinnabarinus(Boisduval) was studied in Israel. Average counts ten days after infestation, at the fourth-leaf stage, ranged from 3·5 to 57 mites per four leaf discs 1 cm in diameter; six lines had significantly low counts, ranging from 0·9 to 1·5 mites per four leaf discs. Fourteen of the lines were also tested at the flowering stage. No mites were found on two lines, and on a third line very few mites were observed. All three lines also had had significantly low mite counts at the fourth-leaf stage. The results suggest there is a definite variation among melon lines in resistance to mite infestation.
Aphid (Hemiptera: Aphididae) populations and the incidence of virus yellows on insecticide-free sugarbeet in south-eastern England in 1978-81
Authors: Thornhill W. A. , Heathcote G. D.
Published: July 2009

The populations of the most common aphid species on sugarbeet, and their principal predators, were monitored on insecticide-free study areas of the crop in south-eastern England in 1978–81. The peak populations of Myzus persicae (Sulzer) varied considerably in size from year to year and were related to the severity of the previous winter. Those of Aphis fabae fabae Scopoli, which occurred slightly later in the season, also varied greatly in size but were not strongly linked to winter temperatures. The sizes of the peak populations of Macrosiphum euphorbiae (Thomas) were similar each year. The annual variation in the level of infection by virus yellows reflected the peak populations of Myzus persicae and not those of the other aphid species. Coccinellids first appeared in the sugarbeet each year in mid-late June, as the aphid populations were developing, and their peak populations did not vary greatly from year to year. Syrphid larvae appeared later in the season than coccinellids, and their numbers seemed closely linked to those of A. f. fabae. Anystid mites were observed on most count dates in all years. The implications of the findings of the study for control of aphids and virus yellows are discussed.
A simple key for the diagnosis of the instars of the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Hemiptera: Aphididae)
Authors: Aalbersberg Y. K. , Westhuizen M. C. Van der , Hewitt P. H.
Published: July 2009

The morphology of the antennae, caudae and wingbuds of Diuraphis noxia (Mordvilko) was used in conjunction with ratios between antennal segment lengths to draw up a key for diagnosis of the instars.
A non-biting midge (Diptera: Chironomidae) of horticultural significance
Authors: Cranston Peter S.
Published: July 2009

Sporadic previous reports of chironomid larvae feeding on roots of horticultural plants are reviewed and related to the growing recognition that a particular parthenogenetic species can damage severely indoor horticultural crops, particularly lettuce and young tomatoes. The taxonomy of the pest, Bryophaenocladius furcatus (Kieffer), is assessed, new synonymy proposed and a neotype and lectotype designated. The species is redescribed from the larva, pupa and adult female.
Biology of Metioche vittaticollis (Stål) (Orthoptera: Gryllidae), a predator of rice pests
Authors: Rubia E. G. , Shepard B. M.
Published: July 2009

The biology of the predacious cricket Metioche vittaticollis (Stål) collected from rice in the Philippines was studied in the laboratory and greenhouse. The cricket preyed on the eggs of a range of insect pests of rice including Chilo suppressalis (Walker), Cnaphalocrocis medinalis (Guenée), Hydrellia philippina Ferino, Mythimna separata (Walker) and to a lesser extent on the eggs of Leptocorisa oratorius (F.). There was no predation on the eggs of Scirpophaga incertulas (Walker).
Mortality of eggs and larvae of the bush fly, Musca vetustissima Walker (Diptera: Muscidae), caused by scarabaeine dung beetles (Coleoptera: Scarabaeidae) in favourable cattle dung
Authors: Ridsdill-Smith T. J. , Hayles L. , Palmer M. J.
Published: July 2009

The mortality of eggs and larvae of Musca vetustissima Walker, caused by two scarabaeine dung beetles was measured in the laboratory in favourable cattle dung at 23°C. Eggs and larvae less than one day old were the main stages killed in the dung. Mortality from beetles that entered dung immediately after fly oviposition was higher than that from beetles that entered the dung one or three days later. The results also indicated that there are differences between species of dung beetles in the mode of action against the fly. The smaller beetle species, Onthophagus binodis (Thunberg), at densities of 120 beetles/pad caused increased mortalities of 12% of fly eggs and 11% of young larvae but did not affect older larvae, while the larger species, O. ferox Harold, at densities of 48 beetles/pad caused no extra mortality of eggs but did cause an increased mortality of 47% of young fly larvae and 61% of older larvae.
The Sugar–Cane Moth Borers in Mauritius
Authors: Moutia L. Andre
Published: July 2009

1. The first record of important damage due to borers in Mauritius dates from 1856, the species being the spotted borer, Diatraea venosata, Wlk. From 1856 to 1897, two other species of borers were introduced, the pink borer, Sesamia vuteria, Stoll, and the white borer, Grapholita schistaceana, Snell. From 1897 to 1916, the damage caused by these three borers decreased gradually, so that from 1916 to 1928 these pests were considered by planters as being of minor importance. From 1928 to 1932 an increase in the damage due to the spotted borer was observed nearly all over the island.

2. The spotted borer causes important damage on the coast belt during the dry and cold months, i.e., April to July. The pink borer, distributed all over the island, causes damage of medium importance to young canes; it occurs with intensity during the wet and hot months of the year, i.e., December to April. The white borer is also distributed nearly all over the island but causes damage of relatively slight importance in plantations, with the exception of very rare occasions when it occurs sporadically as a serious pest.

3. The losses due to the pink and white borers vary with the localities and are difficult to estimate. As an average, Rs.6·00 per arpent is incurred for control leasures against these pests.

The spotted borer which attacks mature canes causes losses both in the field and in the factory. The reduction in the field, per arpent, averages 15 per cent. The loss in sugar averages 2.3 per cent., i.e., 16 per cent, of sugar in cane. The gross loss per annum for the whole island is about 1½ million rupees, and the net loss approximately Rs.125,000.

4. The proportion of canes attacked by the spotted borer averages 30 per cent. From estimates made according to the method of Wolcott, in Porto Rico, it was found that the percentage of borers per 100 lb. of cane is 39, as a mean, and the number of borers per acre averages 15,698. The mean percentage of stems attacked by 1 to 5, 6 to 10, and 11 to 15 borers is of 87·6, 10·1 and 2·2 respectively. The proportion of nodes attacked varies between 10 and 25 per cent. approximately.

5. The cane varieties that are heavily attacked by the spotted borer are M.55, M.131, D.109, M.1474, White Tanna, B.H.10/12, R.P.6, D.K.74, D.130 and R.P.8.

6. The various methods of control used in the island for the last 15 to 20 years are discussed. Against the pink and white borers the use of trap plants is recommended as well as the collection of larvae. The burning of trash in the fields is to be avoided.

In the case of the spotted borer the destruction of larvae in the tops to be planted is recommended. A practical method consists in the immersion of the tops in cold water during 72 hours, or in hot water at 50–51°C. for 2 to 2½ hours, or 52°C. for 30 minutes, or in saturated lime-water for eight hours.

7. The breeding of the larval parasites is recommended on estates where larva collecting is practised.

8. The advantages or disadvantages of larva collecting and burning of trash are still under consideration.
Studies of the Willow-Shoot Moth, Depressaria Conterminella, Zell
Authors: Miles Mary , Miles Herbert W.
Published: July 2009

A study has been made of the biology of Depressaria conterminella, Zell., the most important willow-shoot moth occurring in commercial willow beds of Lancashire and Cheshire.

The eggs are laid in June-July in bark crevices on the stocks near the level of the soil. Hatching takes place in the following spring, beginning about the time the buds open. The eggs are described.

On hatching the larvae travel to the opening buds. First instar larvae tunnel through the outer leaves into the buds, but larvae in the later stages crawl between the leaves, spinning them together to form a feeding shelter. Larvae have four instars and at the third ecdysis there is a marked colour change. Both larval forms are described. In the course of feeding each larva destroys 3–4 shoots. Infested shoots are illustrated. Pupation takes place in the soil and adults emerge after about three weeks.

The habits of the moths are described. The species is univoltine and no instance of parasitism has so far been observed. A list of other Lepidoptera bred from the shoots of willows is given.

The nature of the crop does not permit of costly control measures. The study of the biology suggested that infestation might be checked by delaying harvesting until after the larvae hatched. In an experiment in the field it was found possible to reduce infestation from over 40 per cent. to under 5 per cent. by this method. Infestation was also reduced by burning waste hay over the rows of willow stocks during the dormant season.
Tsetse-Flies in the Masai Reserve, Kenya Colony
Authors: Lewis E. Aneurin
Published: July 2009

Our knowledge of the distribution of tsetse-flies affecting domestic stock in Kenya Colony is of a very general character. A good deal of the information requires confirmation; and much needs to be done to ascertain the extent and the nature of the permanent fly-infested areas, and the seasonal dispersion of the tsetses from their permanent haunts.
A Review of the Species of the Subgenus Trirhithrum, Bezzi (Trypetidae, Diptera)
Authors: Munro H. K.
Published: July 2009

Many years ago Bezzi realised that the species placed in the genus Ceraiitis, MacL., needed division into smaller groups. Among those he first delimited, Carpoph-thoromyia, Aust., may well be retained as a genus, but most of the others, Parda-laspis, Bez., Perilampsis, Bez., Trirhithrum, Bez., etc., have hardly more than sub-generic value. It is therefore proposed to study all the species concerned in order to discover the true limitations of the groups; and also with a view to stabilising the species themselves for a further study involving dissection of specimens. The last point is of some importance because more detailed work on the morphology cannot be carried out at all satisfactorily until one is quite sure of the specific identity of the specimens used. Further, as the dissection of insect types may be undesirable and few institutions, if any, would allow it to be done, it becomes essential to have specimens critically compared with types, and until this is done, there must always remain some element of doubt in identifications. This paper is thus a beginning of a series on a nreliminarv studv of the subsrenera of Ceratitis.
Three Years Mosquito Control Work in Calcutta
Authors: White R. Senior
Published: July 2009

It was in December 1929 that the writer first tried to reduce the terrible mosquito nuisance which each winter plagues the City of Calcutta. His efforts were naturally confined to an attempt to alleviate conditions in the Bengal-Nagpur Railway's Headquarters Colony at Garden Reach, but it soon became obvious that by control in the relatively small area of land belonging to the railway very little could be accomplished, and that to achieve anything appreciable a very much larger acreage would have to be put under control. So when in the ensuing winter of 1930–31 other property owners in the vicinity became aware that this railway was attempting to do something and evinced interest in the matter, advantage was taken of this to form the Garden Reach Anti-Malaria Association, the initiation of which also received a considerable impetus from the virulent outbreak of malaria in the previous autumn at Budge Budge, some 18 miles down-river from the City. This outbreak, and the organisation of and area covered by the Association, are described by Covell (1932).
The impact of yellow stem-borer, Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae), on deepwater rice, with special reference to Bangladesh
Authors: Taylor Brian
Published: July 2009

Using several methods, claims that stem-borers, especially Scirpophaga incertulas (Walker), cause serious crop loss in deepwater rice were tested in Bangladesh. Insecticides were used to control different borer broods. Early season, pre-flood applications reduced infestation, but did not affect yield. One to three mid- to late-season applications of monocrotophos at 250 g a.i./ha significantly reduced infestation and/or whitehead numbers, with yield savings (7-10%) similar to those which earlier workers obtained by applying diazinon 20 times in a season. In each of six years, tiller populations peaked before flooding, then steadily declined until harvest, but stem-borer infestation varied, remaining low until late season in two of the years. In 1981, infestation lower than 24% pre-flood and 42% at harvest did not affect yield. In 1982, eighty-four correlation calculations showed no consistent significant effects of infestation (27-60%, C.V. 40%) on yield (25 000 stems were dissected). Anatomical studies of elongated stems revealed S. incertulas feeding neither causes significant structural damage nor seriously interrupts nutrient flow; also, the passage of a larva through a nodal septum is not detrimental. Irrespective of stem-borer attack, the submerged lower internodes commonly die, the fibrous remains anchor the upper stem, and nodal roots take over nutrient uptake. Studies of panicle-bearing stems (n = 838) showed that, even with 97% stem infestation, most yield loss results from infestation of the terminal internode and is manifested predominantly as whiteheads. In a specific study, 94% whiteheads (n = 205) were associated with terminal internode infestation, where larval feeding in the narrow stem had disrupted food conduction, so preventing grain-filling. The apparent tolerance of S. incertulas by deepwater rice varieties is consistent with their being a primitive group of cultivated rices.
A migration of grasshoppers, particularlyDiabolocatantops axillaris(Thunberg) (Orthoptera: Acrididae), in the West African Sahel
Authors: Reynolds D. R. , Riley J. R.
Published: July 2009

A dense layer of large insects in windborne, migratory flight was observed by radar in the Tilemsi Valley in Mali between about 23.00 and 02.00 h on 10–11 October 1978. The volume density, height of flight, area density, displacement speed and direction, orientation and migration rate were determined for the overflying insects. Light-trap catches and radar signatures provided strong evidence that the pest grasshopperDiabolocatantops axillaris(Thunberg) contributed to the overflying layer. Other species contributing probably includedOedaleus senegalensis(Krauss) and possiblyOchrilidiaspp. ForD. axillaris, the migration can be regarded as a search for overwintering sites by adults in reproductive diapause, and thus is an example of C. G. Johnson's Class III migration. Estimated trajectories placed the probable source areas of the overflying grasshoppers in the Gourma, about 150 km west-south-west of the radar site. Migration direction was approximately downwind, but the grasshoppers showed a degree of common orientation towards the east-south-east, which added a southwards component to their displacement. At 02.30 h on the same night, a very dense line-concentration associated with a wind-shift moved across the radar site, and insects still in flight probably became entrained in this wind convergence zone and added to the line-concentration. Other evidence of long-distance, windborne migration inD. axillariswas adduced from records of captures on ships at sea, mainly off the West African coast. The consequences of downwind displacement and concentration for grasshopper ecology and pest management are discussed. The migration behaviour ofD. axillarisand other grasshopper species probably reduces migration losses by the efficient location of new habitats and forms an essential part of life-history strategies for survival in a sahelian environment.
The olfactory responses of tsetse flies, Glossina spp. (Diptera: Glossinidae), to phenols and urine in the field
Authors: Vale G. A. , Hall D. R. , Gough A. J. E.
Published: July 2009

In Zimbabwe, catches of Glossina morsitans morsitans Westwood and G. pallidipes Austen in traps baited with acetone and 1-octen-3-ol were increased by the addition of the synthetic mixture of eight phenols found in cattle urine to a level equal to or greater than those with natural urine. The addition of natural urine to the synthetic mixture did not increase catches further, indicating that the phenols account for essentially all the attractiveness of cattle urine. 4-Methylphenol and 3-n-propylphenol were shown to be the naturally-occurring components essential for attractiveness, and 2-methoxyphenol was found to reduce attractiveness. 4-Methylphenol alone was slightly attractive to both species, but only for males, increasing catches by approximately 30%. Catches of both species were increased by approximately 50% by 3-n-propylphenol. The addition of 4-methylphenol increased catches of G. pallidipes by up to a further four times, but catches of G. m. morsitans were decreased. Of 14 other phenols tested, phenol, 3-methylphenol and 4-ethylphenol increased the attractiveness of 3-n-propylphenol to G. pallidipes without decreasing the attractiveness to G. m. morsitans; (E)- and (Z)-3-(1-propenyl)phenol, potential contaminants in 3-n- propylphenol, did not reduce the attractiveness of mixtures of 3-n-propylphenol and 4-methylphenol, and the E and, to a lesser extent, the Z isomer could substitute for 3-n-pro-pylphenol in these mixtures. Mixtures of phenols which increased the attractiveness of traps to tsetse showed similar effects with targets but at a slightly reduced level.
Landing responses of the tsetse fly Glossina morsitans morsitans Westwood and the stable fly Stomoxys calcitrans (L.) (Diptera: Glossinidae & Muscidae) to black-and-white patterns: a laboratory study
Authors: Brady John , Shereni William
Published: July 2009

The landing preferences of fed males of Glossina morsitans morsitans Westwood and Stomoxys calcitrans (L.) were measured under constant conditions in a two-choice situation. Pairs of black-and-white landing targets were presented on the grey walls of an arena ca 60 cm in diameter. In a simple choice of blackness vs whiteness, G. m. morsitans showed a ninefold greater preference for black; S. calcitrans displayed no preference. G. m. morsitans landed twice as frequently on a 15×30-cm vertical black stripe as on a horizontal one, but S. calcitrans preferred the horizontal one. Comparisons between a vertical stripe (or a horizontal one) and similar stripes sloping at various angles indicated that at about 50° G. m. morsitans distinguished the sloping stripe from the vertical (or the horizontal), but did not well distinguish slopes closer to the vertical (or horizontal). Tests with multiple vertical stripe patterns indicated that G. m. morsitans did not significantly distinguish between a single 15-cm stripe and two- or three-striped targets of the same total black area, but landed significantly less frequently on targets of four or five stripes, implying an angular, behavioural visual ‘resolution' of roughly 17°; S. calcitrans responded similarly. Both species showed a marked preference for landing near the edge of the black on all targets, with G. m. morsitans strongly biassed to the black side of an interface.
Gyranusoidea tebygi sp. n. (Hymenoptera: Encyrtidae), a parasitoid of Rastrococcus (Hemiptera: Pseudococcidae) on mango in India
Authors: Noyes J. S.
Published: July 2009

Gyranusoidea tebygi sp. n., an encyrtid parasitoid of Rastrococcus on mango in India, is described and compared with related species. The parasitoid is to be introduced into West Africa in an attempt to control the mealybug, which is a serious pest of mango and citrus in some West African countries.
The parthenogenetic midge of water supply systems,Paratanytarsus grimmii(Schneider) (Diptera: Chironomidae)
Authors: Langton P. H. , Cranston P. S. , Armitage P.
Published: July 2009

Chironomid midges have been known to include parthenogenetic species for over a century. One of these species,Paratanytarsus grimmii(Schneider), cited under several different names here shown to be junior synonyms, has attained some notoriety as a pest. Its occurrence as a supposedly paedogenetic (actually pharate adult parthenogenetic) inhabitant of water distribution systems is discussed and related to its more usual occurrence in a variety of small water bodies including aquaria. New synonymy is proposed and a lectotype designated.
A remote sensing method for the estimation of light-trap efficiency
Authors: McGeachie W. J.
Published: July 2009

A description is given of the use of a video camera to estimate light-trap efficiency in the field. This camera relies on the extra light sensitivity provided by the Newvicon detector tube to enable insect track discrimination. Recorded insect flight tracks were classified into three distinct categories, new arrivals, passers by and local flights, the numbers of which were compared to the moth catch in a Robinson mercury vapour light-trap. Calculations of efficiency were made using two methods, the best-estimate efficiency, obtained by comparing the new-arrival tracks to the light-trap catch, and the worst-estimate efficiency, obtained by comparing new-arrival tracks plus passer-by tracks to the light-trap catch. Preliminary results indicate that efficiency varies with windspeed but with a maximum of 39%, obtained in virtually calm conditions, suggesting that some aspect of moth behaviour limits trapping efficiency. It is suggested that the speed of migration of screening pigment from the dark-adapted state to the light-adapted state in superposition eyes may have a bearing on the catching mechanism of a light-trap.
Ecology, distribution and host relationships of ticks (Acari: Ixodidae) infesting livestock in Mali
Authors: Teel P. D. , Bay D. E. , Ajidagba P. A.
Published: July 2009

A survey for ticks on livestock with emphasis on ticks parasitizing cattle was conducted below 16°N lat. in Mali. Seventeen species of ixodid ticks were recovered from cattle, 12 from sheep, five from goat, four from horse, one from donkey and four from camel. Amblyomma variegatum (F.), Boophilus geigyi Aeschlimann & Morel, Hyalomma marginatum rufipes Koch and H. truncatum Koch were widespread, and could each be collected as adults from cattle throughout the year in certain regions. A. variegatum was most numerous from the tropical woodlands to the Sahelo-Sudanian steppe. The prevalence of B. geigyi in Mali confirms an extended distribution of this species in West Africa. B. annulatus (Say) and B. decoloratus (Koch) were prevalent in the inland delta area and in south-western Mali. H. m. rufipes and H. truncatum were most numerous in the Sudanian and Sahelo-Sudanian steppe. H. dromedarii Koch, H. impeltatum Schulze & Schlottke and H. impressum Koch were collected in the steppeland areas. H. nitidum Schulze was collected for the first time in Mali. This comparatively more hydrophilic species was prevalent in the North Guinean forest and Sudano-Guinean vegetation zones. Of eight Rhipicephalus species from livestock, seven were collected from cattle: R. cuspidatus Neumann, R. evertsi evertsi Neumann, R. guilhoni Morel & Vassiliades, R. muhsamae Morel & Vassiliades, R. sanguineus (Latreille), R. senegalensis Koch and R. lunulatus Neumann. R. sulcatus Neumann was obtained only from sheep. The distribution and phytoclimatic associations of these species are discussed.
Population dynamics of the coconut caterpillar, Opisina arenosella Walker (Lepidoptera: Xyloryctidae), in Sri Lanka
Authors: Perera P. A. C. R. , Hassell M. P. , Godfray H. C. J.
Published: July 2009

Opisina arenosella Walker is a defoliating pest of coconut in Sri Lanka. A first attempt was made to understand its population dynamics. Analysis of records of population outbreaks throughout the country from 1965 to 1985 revealed cycles in the population of approximately one generation period, giving the population the appearance of partially discrete generations. There was also evidence for longer cycles of six-month period. Outbreaks occurred throughout the coconut-growing regions of Sri Lanka, and the numbers of outbreaks per year in different provinces were sometimes correlated, indicating a common, probably climatic, triggering mechanism. Parasitism remained high throughout the outbreaks and there was some evidence that pupal parasitism increased towards the end of an outbreak. A working hypothesis that explains the population dynamics of O. arenosella and the origin of outbreaks is presented.
Migration and dispersal of the Rutherglen bug, Nysius vinitor Bergroth (Hemiptera: Lygaeidae), in eastern Australia
Authors: McDonald Garrick , Farrow Roger A.
Published: July 2009

Aerial sampling for Nysius vinitor Bergroth was undertaken in the surface and upper air, at altitudes of 2 and 100-300 m, respectively, at Trangie in central New South Wales and at Corny Point, Yorke Peninsula, South Australia. Insects were sampled for 15 periods, each of 3-11 days, between October 1979 and February 1984, covering all months except January, March and May. N. vinitor was one of the most abundant insects caught in the upper air during the day and night (mean density of 652/106 m3), while the congeneric N. clevelandensis Evans was rarely caught at any time. N. vinitor was caught in all months sampled except for the winter months of July and August, and the largest daily catches occurred in September. Females were generally less common than males, although the relative incidence in the upper air catches frequently increased significantly from day to night. Fewer mature females were caught in the upper air (0-16·8%) than at the surface (0-48·4%). Densities were generally much greater in the surface air than in the upper air, although during the major flights of spring, there was less than a two-fold difference, indicating increased migratory activity. Migration occurred in a range of synoptic conditions resulting in the displacement of individuals in a variety of directions and distances depending on synoptic flow at the time of flight. Major migrations occurred at night, following dusk take-off, in disturbed weather associated with prefrontal airflows. These resulted in net southward displacements of ca 200-300 km depending on flight duration. It is suggested that major immigration flights into central-western New South Wales and regions to the south regularly occur in early spring (September-October) and probably arise from breeding areas in subtropical latitudes.
The genusMyndus(Hemiptera: Cixiidae) in the solomon islands and Vanuatu and its relation to foliar decay of coconut palms in Vanuatu
Authors: Wilson M. R.
Published: July 2009

The species of the cixiid genusMyndusoccurring in the Solomon Islands and Vanuatu are reviewed.M. macfarlaneisp. n. is described from Santa Cruz Islands. It is distinguished fromM. mavorsFennah andM. taffiniBonfils, both of which are redescribed and illustrated. All species have been collected from coconut palms, andM. macfarlaneialso from areca palm (Areca catechu).M. taffinihas been previously confirmed as the vector of foliar decay of coconut palms in Vanuatu.
Insect abundance in field beans altered by intercropping
Authors: Tingey Ward M. , Lamont W. J.
Published: July 2009

Densities of four herbivorous insect species were compared on field beans (Phaseolus vulgaris) grown in monoculture and those grown in relay intercropping with winter wheat. In three years of study in New York State, population densities of Empoasca fabae (Harris) and Aphis fabae Scopoli were significantly less in plots intercropped with winter wheat than in those grown in monoculture. In contrast, intercropping was associated with greater densities of Lygus lineolaris (Palisot de Beauvois) and Systena frontalis (F.). An increased density of L. lineolaris may be an economic risk factor in beans intercropped with wheat because only this species of the four studied feeds exclusively on the flowers and developing seed pods.
A microtitre plate assay for characterizing insensitive acetylcholinesterase genotypes of insecticide-resistant insects
Authors: Moores Graham D. , Devonshire Alan L. , Denholm Ian
Published: July 2009

A rapid technique is described for characterizing and monitoring, in single insects, the insensitivity of acetylcholinesterase (AChE) to organophosphorus and carbamate insecticides. Ninety-six insects are homogenized simultaneously in a microtitre plate and portions (e.g. 0·05 for Musca domestica L.) assayed colorimetrically with acetylthiocholine in the presence and absence of diagnostic concentrations of insecticide. Reactions are monitored by a kinetic microplate reader linked to a microcomputer that determines mean AChE activities automatically by linear regressions of absorbance-time data. Mean inhibited activity is then expressed as a percentage of uninhibited activity. Several inhibitors can be tested against the same insect to yield an ‘insensitivity profile‘ of individuals and strains. In tests on M. domestica adults of known AChE genotype, the assay clearly distinguished not only between a sensitive and two slightly (3-15-fold) insensitive AChE variants but between all six genotypic combinations of these three alleles.
Rearing and aspects of biology of Cephalonomia stephanoderis and Prorops nasuta (Hymenoptera: Bethylidae) parasitoids of the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae)
Authors: Abraham Y.J. , Moore D. , Godwin G.
Published: July 2009

Cephalonomia stephanoderis Betrem and Prorops nasuta Waterston are two bethylid parasitoids obtained from Africa for the biological control of the coffee berry borer, Hypothenemus hampei (Ferrari) in Mexico and Ecuador. Rearing methods and life-cycle studies carried out under controlled conditions are described for both the parasitoids and H. hampei. Scanning electron micrographs are shown of the developmental stages of the parasitoids. Data are given on development times, pre-oviposition period and on the mating and oviposition behaviour of C. stephanoderis.