bluuebunny/crossref_metadata_2025_split huggingface dataset:
Jumping plantlice (Hemiptera: Psylloidea) attacking avocado pear trees,Persea americana, in the New World, with a review of Lauraceae-feeding among psylloids
Authors: Hollis D. , Martin J.H. 
Published: July 2009

AbstractFour species of the psylloid genusTriozadamagePersea americanain Central and South America; two of these species,T. aguacateandT. godoyaeare described as new; an identification key is provided for the sixTriozaspecies known to develop onPerseaspecies in the New World. A review is given of the psylloid species associated with the plant family Lauraceae.
Seasonal trends in the rate of population increase of Frankliniella occidentalis (Thysanoptera: Thripidae) on cucumber
Authors: Jarošík V. , Koliáš M. , Lapchin L. , Rochat J. , Dixon A.F.G. 
Published: July 2009

AbstractThe developmental rate of Frankliniella occidentalis (Pergande) was determined on cucumber Cucumis sativus cv. Sandra over a range of constant temperatures. The lower developmental threshold (LDT) and the sum of effective temperatures (SET) for the pre-imaginal development were 10.7°C and 231.1°C, respectively. The rate of population increase was assessed as the sum of effective temperatures above the lower developmental threshold by monitoring the numbers of thrips on individual leaves of cucumber under commercial greenhouse conditions. Population growth was characterized by an early stochastic phase, corresponding to pre-imaginal development of the first generation, and followed by an exponential phase starting with the second generation, the rate of which did not vary between plants. Throughout the exponential phase, the rate of population growth increased with time/age of plant. As significant damage to cucumber may occur during the exponential phase of population increase, the sum of effective temperatures of 231°C can be used to predict when damage is likely to start to occur.
Influence of intercropping on the abundance, distribution and parasitism of Chilo spp. (Lepidoptera: Pyralidae) eggs
Authors: Päts P. , Ekbom B. , Skovgård H. 
Published: July 2009

AbstractTwo of the most common and serious pests of maize and sorghum in the coastal areas of East Africa are the pyralid species, Chilo partellus (Swinhoe) and C. orichalcociliellus (Strand). Maize monocrop (with high and low plant density) and maize/cowpea mixed intercrop field experiments were conducted in Kenya to test if intercropping decreased the number of egg batches laid, altered the distribution of the egg batches and influenced egg parasitism. There was no significant difference in the number of egg batches per plant between treatments and the egg batches were randomly distributed on and among plants in most of the plots for all three treatments. There was a tendency for higher egg parasitism in the intercrop. The proportion of eggs parasitized was significantly correlated with total number of eggs per plot suggesting a positive density dependent response. It is concluded that intercropping does not affect C. partellus nor C. orichalcociliellus oviposition behaviour but egg parasitism is likely to be augmented.
Selectivity of insecticides to Encarsia pergandiella (Hymenoptera: Aphelinidae), an endoparasitoid of Bemisia argentifolii (Hemiptera: Aleyrodidae)
Authors: Stansly P.A. , Liu T.-X. 
Published: July 2009

AbstractEncarsia pergandiella Howard is the most abundant parasitoid of silverleaf whitefly, Bemisia argentifolii Bellows & Perring, in south Florida vegetable fields and can contribute significantly to natural biological control of this and other whitefly species. However, quality standards, costs, and risks in commercial tomato production are high, resulting in frequent recourse to chemical control. Therefore, successful utilization of biological control could depend on compatibility of the parasitoid with selective insecticides. We tested a wide range of potentially selective insecticides, represented by a mineral oil, an insecticidal soap, a neem seed extract and synthetic and natural sugar esters, against eggs, first and third instar larvae, pupae and adults, using a pyrethroid, CaptureR (20 g bifenthrin/1 EC), for comparison. CaptureR residues on nymphs exposed to adult parasitoids reduced parasitization more than other materials tested, and were most toxic to all parasitoid stages. Mineral oil caused high mortality to immature parasitoids, and residues reduced parasitization of E. pergandiella. However, oil residues were much less toxic to adults if applied as a spray to leaf surfaces than as a dip to a leaf and especially glass surfaces. In contrast, the toxicity of CaptureR was high regardless of bioassay method. Neem extract, insecticidal soap and both sugar esters tested had little or no effect on E. pergandiella. These latter materials could be considered selective in respect to E. pergandiella and might be used to suppress B. argentifolii without decimating parasitoid populations.
Chilo partellus (Lepidoptera: Pyralidae) moth and larval response to levels of antixenosis and antibiosis in sorghum inbred lines under laboratory conditions
Authors: van den Berg J. , van der Westhuizen M.C. 
Published: July 2009

AbstractTwo experiments were conducted to determine Chilo partellus (Swinhoe) moth and larval response on sorghum lines differing in levels of antibiosis and antixenosis. The inbred lines were E 302, IS 2205, IS 2122 and SA 2681, all reportedly varying in levels of antibiosis and ovipositional and larval antixenosis to C. partellus. Ovipositional antixenosis was evaluated in choice tests under cage conditions and significant differences were observed in the average number of egg batches per line. E 302 received the greatest number of egg batches. Antibiosis and larval antixenosis was evaluated with artificial infestation in a greenhouse. Significant differences occurred in larval numbers and mean larval mass on different lines, with E 302 possessing the greatest level of antibiosis resistance. This study indicates that resistant genotypes such as E 302 may exhibit high levels of antibiosis or larval antixenosis, but may also be preferred for oviposition. The size of egg batches was not influenced by ovipositional antixenosis. The potential effect of ovipositional antixenosis mechanisms on pest populations under field conditions is discussed.
Off-target effects of ivermectin on insects and on dung degradation in southern Alberta, Canada
Authors: Floate K.D. 
Published: July 2009

AbstractInsect activity was significantly reduced in dung from cattle treated with a recommended topical dose (500 μg/kg) of the endectocide, ivermectin. Reductions affected an ecologically and taxonomically diverse group of insects including coprophagous flies, parasitic wasps, and both predacious and coprophagous beetles. Whereas some species appeared unaffected by faecal residues, the emergence of other species was reduced in dung voided ≤ 12 weeks post-application. The species most affected were the flies, Sepsis sp. and Coproica mitchelli (Malloch). eucoilid wasps. and the beetles, Cercyon quisquilius (Linnaeus) and C. pygmaeus (Illiger). Results were consistent within and between years. Similar reductions have been reported previously, but typically for a much shorter post-application period. The greater duration of effect observed in the current study is attributed to a more accurate bioassay, species-level identifications, and the use of sample sizes generally larger than those used in previous studies. Reduced insect activity was associated with slower dung pat degradation. When ivermectin was added directly to dung, at levels previously reported to occur in dung from treated cattle, the treated dung had not appreciably degraded after 340 days in the field. In contrast, untreated dung pats deposited at the same time and place had largely degraded after 80 days in the field. The effect of ivermectin use on pasture quality is probably ‘moot’ in southern Alberta because of the current pattern of use. Should this pattern change, however, results of the present study validate the need for future studies to assess the off-target effects of ivermectin use on pasture quality.
The magnitude of site and time interaction effect in tsetse fly (Diptera: Glossinidae) trap catches
Authors: Odulaja A. , Mihok S. , Abu-Zinid I.M. 
Published: July 2009

AbstractSite and time effects are important factors determining trap catches of tsetse flies. These factors may interact significantly and therefore confound interpretation of time series data used for population monitoring. We therefore investigated the magnitude and importance of site × time interactions in trap catches of Glossina pallidipes Austen and G. longipennis Corti using a 2200 trap-days (400 trap-months) data set. The interaction was found to be siginificant (p<0.05) in 46–100% of the combinations of different numbers of months and sites between 2 and 12. The mean percent variance due to the interaction ranged between 4% and 28% for G. pallidipes and 12% and 36% for G.longipennis. The interaction was usually less important than the effect of site alone but more important than the effect of time alone. These results suggest that tsetse researchers should examine critically the adequacy of existing approaches to population monitoring with traps and to testing new traps and odour baits.
Estimates of population density and dispersal in the blowflyLucilia sericata(Diptera: Calliphoridae)
Authors: Smith K.E. , Wall R. 
Published: July 2009

AbstractTo investigate the population density and dispersal of the sheep blowflyLucilia sericata(Meigen) mark-release-recapture trials were carried out in lowland pastures in south west England. In three trials, 2142, 1351 and 451 fluorescent dust marked flies were released of which 4%, 14% and 10% were recaptured using a grid of sticky, odour-baited targets, placed between 8 m and 1000 m from the release point. There was no significant effect of wind direction on dispersal pattern and no apparent directional movement of the flies from the release point. Using the method described by Hawkes (1972) the mean distance travelled by all the flies on the first day of each of the three trials was calculated to be 108 m, 128 m and 137 m respectively. Using the method described by Fletcher (1974) the mean distances travelled were calculated to be 135 m (±42), 118 m (±27) and 183 m (± 61) on the first day of each of the three trials, respectively. The median distances travelled by the flies on the first day of each of the three trials were calculated to be 109 m, 130 m and 150 m, respectively. A Lincoln Index was used to estimate the population density of wild femaleL. sericata.The number of female flies was estimated to be zero in June, approximately one per hectare in July and six per hectare in August in 1994.
Influence of the host plant of the cassava mealybugPhenacoccus manihoti(Hemiptera: Pseudococcidae) on biological characteristics of its parasitoidApoanagyrus lopezi(Hymenoptera: Encyrtidae)
Authors: Souissi R. , Le Rü B. 
Published: July 2009

AbstractThe influence of the host plant of the cassava mealybug,Phenacoccus manihotiMatile Ferrero on the encyrtid parasitoidApoanagyrus lopeziDe Santis was studied in the laboratory. Four different host plants were used: two cultivars of cassava,Manihot esculenta(Euphorbiaceae), cv. Incoza and cv. MM79; Faux caoutchouc, a hybrid ofM. esculenta × M glaziovii;and talinumTalinum triangularae(Portulacaceae), a common weed in cassava fields. Plants were selected for different levels of antibiotic resistance toP. manihoti. Mealybug mortality due to host feeding by the adult parasitoid and the percentage of mealybugs parasitized were significantly lower when mealybugs were reared on theManihotcultivars and hybrid than when reared on talinum. However, the encapsulation rate was significantly lower inP. manihotireared on talinum. The highest percentage parasitism and the lowest rate of emergence were recorded on cv. Incoza, the most resistantManihotcultivar. The sex ratio did not vary significantly with the host plant used. The total developmental time and size of male and female progeny ofA. lopezidiffered significantly betweenP. manihotireared on different host plants. AmongManihotplants, parasitoid size was positively correlated with development time and negatively with plant resistance. Results suggest that the parasitoid,A. lopezi, might perform better if cassava cultivars were selected for their strong antixenosis but low antibiotic characteristics.
Nutritional states of male tsetse flies (Glossina spp.) (Diptera: Glossinidae) caught in odour-baited traps and artificial refuges: models for feeding and digestion
Authors: Hargrove J. W. , Packer M. J. 
Published: July 2009

AbstractMale Glossina morsitans morsitans Westwood and Glossina pallidipes Austen caught in artificial refuges in Zimbabwe had ca. six times as much haematin and up to 32% more fat than flies from odour-baited traps, but haematin-specific fat levels did not differ significantly between methods. G. pallidipes estimated to have fed < 9 h prior to sampling contained ca. 3.3 mg fat - only 10% less than peak levels. A differential equation model for blood-meal metabolism was developed which described well the changes in fat levels of laboratory G. m. morsitans and the relationship between fat and log haematin in field data. The model predicts a mean feeding interval (T) of 54 – 65 h and mean fat levels of ca. 2.8 mg for G. pallidipes at feeding. When haematin frequency data were analysed as suggested in the literature, estimates of feeding rates and intervals, and of the non-feeding phase, varied with sampling method. Published estimates of activity levels related to feeding suggest a model where feeding rates increase approximately linearly during the trophic cycle. For T = 58 h the model gives good predictions of mean fat levels and variances in both species, with starvation rates < 1% / day. Models with long non-feeding phases predict fat levels up to 40% lower than observed and with smaller variances. For constant feeding rates, fat levels were well predicted for T = 54 h, but predicted death rates (> 5% / day due to starvation alone) were impossibly high. It is suggested that a proportion of tsetse flies with high fat levels feed on mobile hosts early in the trophic cycle and that this effect is more marked for G. m. morsitans than for G. pallidipes. Over-estimates of T result from the failure to consider these tsetse flies and not to errors in the assumed time scale, nor failure to catch high-fat tsetse flies which visit stationary traps.
Effects of lunar phase on light trap catches of the Malayan black rice bug, Scotinophara coarctata (Heteroptera: Pentatomidae)
Authors: Ito Kiyomitsu , Sugiyama Hachiro , Nik Salleh Nik Mohd. Noor b. , Poon Min Chang 
Published: July 2009

AbstractDaily light trap catches of Scotinophara coarctata (Thunberg) were analysed from mid-September 1986 to December 1990 and the physiological status of the trapped adults was examined. The catch size fluctuated synchronously with the lunar phase; large catches occurred around the full moon period and very few adults were trapped around the new moon period. Seasonally, the catches were large from January to March and from July to September, while they were small from May to June and October to November. The seasonal fluctuations of the catches seemed to be related to the growth stages of the rice plants on which the adults multiplied. The sex ratio of trapped adults was biased toward males, unlike that of the cage-reared insects which was 1:1. Most of the trapped females showed undeveloped ovaries and some of these females appeared to have oviposited previously. Light-attracted adults showed a considerable tolerance to starvation and survived for 20–30 days when they were given water, but for only two days in the absence of water. When the light-attracted females were supplied with food, their ovaries developed rapidly and females with mature eggs were produced after nine days. When the starvation period was prolonged, the ovaries remained immature and the fat bodies reduced in size. The nocturnal take-off of the adults was not triggered simply by the full moon illumination. Adult eclosion did not synchronize with the moon cycle.
Plant density and wheat stem sawfly (Hymenoptera: Cephidae) resistance in Syrian wheats
Authors: Miller R.H. , Masri S. El , Jundi K. Al 
Published: July 2009

AbstractBread and durum wheat varieties varying in wheat stem sawfly resistance were sown at different densities in northern Syria for two seasons to examine the effect of density on plant characteristics related to infestations of the wheat stem sawflies Cephus pygmeus (Linnaeus) and Trachelus spp. Plants sown at low densities had a longer interval between developmental stages and had higher stem solidity than those sown at high densities. Stem solidness was negatively correlated with the percentage of sawfly-infested stems. Plant height and grain yield were neither strongly nor consistently correlated with wheat stem sawfly infestation but were influenced by variety and density. These results differ from those of previous studies in North America where widely spaced plants suffered higher infestations than did closely spaced plants. Results of our study suggest that stand density should be considered when recommending wheat stem sawfly-resistant wheats to farmers in west Asia and North Africa and when designing screening trials for wheat stem sawfly resistance in the field.
Observations on the parasitoid complexes of budmoths (Lepidoptera: Tortricoidea) on larch in Europe
Authors: Mills N.J. 
Published: July 2009

AbstractThis paper reports the results of a survey of parasitism of budmoths on larch in Europe as part of a programme to determine the potential of European parasitoids for the classical biological control of the North American defoliator,Zeiraphera canadensisMutuura & Freeman. The parasitoid complexes ofZeiraphera diniana(Guenée),Exapate duratella(Heyden),Ptycholomoides aeriferanus(Herrich-Schäffer) andSpilonota laricana(Heinemann) are determined from field-collected samples of host larvae and pupae. The parasitoid complexes are characterized by their component guilds and the mean apparent parasitism of the individual species. Host phenology appears to affect the parasitoid complex of the larch budmoths. Parasitoids that attack the young larval instars are better represented from hosts that overwinter as larvae, while parasitism is dominated by the guilds that attack the late larval instars in hosts that overwinter as eggs. The study identifies the ichneumonids,Phytodietusspp.,Chorinaeus cristator(Gravenhorst) andPhaeogenes osculator(Thunberg) for further experimental investigation as potential candidates for the biological control ofZ. canadensis.
Bemisia tabaci (Hemiptera: Aleyrodidae) trap catches in a cassava field in Côte d'Ivoire in relation to environmental factors and the distribution of African cassava mosaic disease
Authors: Colvin J. , Fishpool L.D.C. , Fargette D. , Sherigton J. , Fauquet C. 
Published: July 2009

AbstractAfrican cassava mosaic virus (ACMV), vectored by the whitefly, Bermisia tabaci (Gennadius), is considered the most damaging pathogen of any African crop. Information about vector movement is important for understanding the epidemiology of this disease and the experiments reported here were designed to examine B.tabaci flight activity both in and around a cassava crop in relation to time of day, crop growth stage, wind direction and speed, and to the resulting pattern of infected plants within the field at harvest. At wind speeds of <0.4 ms−1 adult B. tabaci approached the yellow traps by flying upwind. At greater wind speeds, significantly fewer B. tabaci adults approached the traps from downwind, thus reversing the directionally of the catch. When the direction of the prevailing south-west wind reversed, so did the directionality of the catch. Bemisia tabaci adults were flight active throughout the day and the greatest percentage were caught above the canopy between 06.00–08.00 h, when wind speeds were lowest. Trap height and position significantly affected catch with the greatest numbers caught on the lowest traps. More than three times as many B. tabaci adults were caught on traps situated downwind from the field compared to those upwind. Suggesting that the field was acting as a source of whiteflies. In both years, Africa cassava mosaic disease (ACMD) incidence was highest and lowest, respectively, on the edges and in the middle of the trials, with the highest incidence occuring on the edges facing the prevailing wind direction. These results are discussed in relation to the epidemiology of ACMD and to potential cultural control methods such as the use of ACMD-resistant guard rows to protect a mainly susceptible crop.
Seasonal abundance and parasitism of Mesoclanis seed flies (Diptera: Tephritidae) in South Africa, and implications for the biological control of Chrysanthemoides monilifera (Asteraceae) in Australia
Authors: Edwards P.B. 
Published: July 2009

AbstractThe seasonal abundance and rates of parasitism of three species of Mesoclanis seed flies was studied in South Africa. The three species occur on Chrysanthemoides monilifera, and were recorded during most months of the year, whenever C. monilifera was flowering. At three sites in KwaZulu-Natal, numbers of eggs per capitulum of Mesoclanis polana Munro were highest on C. monilifera rotundata between June and November (winter/spring), towards the end of the main flowering flush. Parasitism of M. polana was between 50% and 90% for most of the year. Two other species of Mesoclanis (M. magnipalpis Bezzi and M. dubia Walker) occurred together on C. m. rotundata in the Eastern Cape (St Francis Bay), where parasitism during the year was between 55% and 95%. Peak numbers of eggs per capitulum (M. magnipalpis and M. dubia combined) occurred in May/June (winter), in the latter part of the main flowering flush. Mesoclanis magnipalpis was the only species recorded on C. m. pisifera in De Hoop Nature Reserve (Western Cape), where there was only one peak of oviposition (May/June), coinciding with the short and discrete flowering period of this subspecies. Parasitism was between 50% and 65%. At least nine species of parasitoid were reared from immature Mesoclanis stages. Eurytoma sp. (Eurytomidae) was a dominant parasitoid at all sites. Results are discussed in relation to the possible effectiveness of species of Mesoclanis seed flies as biological control agents of C. monilifera in Australia.