bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of heteropteran predators (Het., Anthocoridae, Miridae) on larval populations of hawthorn psyllids (Hom., Psyllidae)
Authors: Novak H. , Achtziger R. 
Published: August 2009

AbstractThe relationship between hawthorn psyllids and their main natural enemies was studied in Upper Frankonia (Bavaria, Germany) for 4 years. Throughout this period, the most abundant psyllid species were Cacopsylla melanoneura and C. peregrina (Psyllidae) which passed through their larval periods on the hawthorn in spring. Only a few individuals of Cacopsylla crataegi were recorded, with a seasonal occurrence of the larval instars of this species in the summer months. Psyllid larvae were observed to be heavily attacked by a multitude of arthropod predators and psyllid densities on branches where predators had been excluded were significantly higher than on branches with predators present. The heteropterans Anthocoris nemorum, A. nemoralis (Anthocoridae) and Atractotomus mali (Miridae) were considered to be the most important natural enemies of hawthorn psyllids; they regularly reached high densities on hawthorn shrubs and showed a close synchronization with the development of psyllid larvae in each year. All three species exhibited a positive numerical relationship with the abundance of psyllid larvae with A. nemoralis and A. mali exploiting this food resource more effectively than A. nemorum, which is known to be a very polyphagous species. Despite high predation pressure on psyllid larvae, it is concluded that these heteropteran predators are not able to prevent outbreaks of psyllids under favourable climatic conditions as their numerical response to growing psyllid densities occurs with a distinct time delay.
The life history of Rodolia iceryae Janson (Col., Coccinellidae) and the potential for use in innoculative releases against Icerya pattersoni Newstead (Hom., Margarodidae) on coffee
Authors: Kairo M. T. K. , Murphy S. T. 
Published: August 2009

AbstractRodolia iceryae Janson is a predator of Icerya pattersoni Newstead, which is a pest of coffee in Kenya. It was studied under controlled conditions at 27°C and 70% relative humidity. The beetle mates 1–2 days after emergence. Eggs were laid in very close association with the host suggesting that R. iceryae was well adapted to exploit I. pattersoni. The duration of immature development was 36.3 days and adult longevity ranged from 15 to 74 days. Measurements of the sizes of different developmental stages were also taken. The age‐specific fecundity and life table statistics under laboratory conditions were determined as follows: R0, 50.160; G, 61.175; rm, 0.064; Λ, 1.067; and population doubling time, DT, 10.830 days. These statistics suggest that the beetle may be an effective agent as it has the potential to multiply much faster than its host. The host specificity of R. iceryae is also discussed in relation to other Rodolia spp. and it is concluded that the beetle will be restricted to feeding on I. pattersoni.
Persistance and potency of Bacillus thuringiensis against Phthorimaea operculella (Zell.)(Lep., Gelechiida) in potato stores
Authors: Salama H. S. , Zaki F. N. , Ragaei M. , Sabbour M. 
Published: August 2009

AbstractThe persistance of Bacillus thuringiensis var. kurstaki HD‐1 and its potency as a control agent to reduce the losses caused by the potato tuber moth Phthorimaea operculella in stores has been investigated. In stores where shady conditions exist, the persistance of B. thuringiensis lasts longer as compared to the short persistance in the field where ultraviolet radiation is the main effective factor. B. thuringiensis proved that it could protect the potato tubers when applied inside stores for periods up to 255 days, particularly at high doses.
Nuclear polyhedrosis virus of the European pine sawfly, Neodiprion sertifer (Geoffr.) (Hym., Diprionidae) retains infectivity in soil treated with simulated acid rain
Authors: Saikkonen K. 
Published: August 2009

AbstractThe effect of simulated acid rain on the infectivity of the nuclear polyhedrosis virus of the European pine sawfly, Neodiprion sertifer (Geoffr.) was studied in southern Finland. Three‐year‐old saplings of Scots pine, Pinus sylvestris (L.), were sprayed once with diluted N. sertifer virus nuclear polyhedrosis (NsNPV) suspension or distilled water; after this they were irrigated during the growing season with ground water (pH 7) or with acidified water of pH 4 or pH 3, adjusted by adding both H2SO3 and HNO3. The ability of virus‐killed N. sertifer larvae to shelter viruses was tested by killing larvae with NsNPV on half of the virus‐treated saplings before the beginning of the irrigation treatments. The persistence of the virus on the foliage and in the soil was tested the following summer by two separate bioassays with European pine sawfly larvae. In the first bioassay, in which larvae were fed once with the foliage of the experimental saplings, no significant difference in mortality among the various treatments was detected. In the second bioassay, in which larvae were fed on pine foliage contaminated with soil from the virus‐treated saplings, virus treatment had a significant effect. In that case, only 4–7% successfully formed cocoons, compared to larval survival of 22% in the absence of the virus. Of the larvae fed with pine twigs contaminated with soil from saplings on which virus‐infected larval cadavers were retained, the mortality rate was 100%. Acid rain treatments did not affect larval survival in either bioassay. Thus, NsNPV infectivity in the field is maintained in the soil but not on the foliage and appears to be unaffected by simulated acid rain.
Behavioural and chemical investigation of trail pheromone from the termite Reticulitermes hesperus Banks (Isopt., Rhinotermitidae)
Authors: Grace J. K. , Wood D. L. , Kubo I. , Kim M. 
Published: August 2009

AbstractA single active fraction, eliciting both induction of trail‐following and trail orientation, was isolated by HPLC from dichloromethane extracts of excised fourth and fifth sternites of Reticulitermes hesperus workers. GC separation of the active high performance liquid chromatography (HPLC) fraction and subsequent bioassays indicated that a single major component is responsible both for induction of trail‐following and for orientation of termites on the trail. Solvent extracts of intact termite bodies and excised sternites elicited greater trail‐following activity than extracts of excised abdomens or thoraxes not separated from heads. Workers from two geographically separate colonies responded similarily to dichloromethane extracts of intact bodies and excised sternites from members of either colony, providing no evidence of extractable colony‐recognition compounds, although the results suggest that different colonies may produce different quantities of trail pheromone.
Factors influencing the distribution of larval mosquitos of the genera Aedes, Culex and Toxorhynchites (Dipt., Culicidae) on Moorea
Authors: Becker J. 
Published: August 2009

AbstractFive habitat parameters were recorded during the sampling of larvae‐positive water‐filled containers located on the north side of Moorea in French Polynesia: container type, area of container aperture, organic load, water volume, and amount of canopy cover. This survey revealed that the amount of canopy cover significantly influenced both Toxorhynchites amboinensis and Culex quinquefasciatus larval distributions. Culex quinquefasciatus preferred containers in habitats with no canopy cover or light canopy cover compared to those with heavy canopy cover. Toxorhynchites amboinensis preferred heavy‐canopy habitat over habitat with no canopy cover. In addition, C. quinquefasciatus larvae were significantly more common in high‐water‐volume sites compared to low‐water‐volume sites. None of the habitat factors were correlated with a combined Aedes polynesiensis and Aedes aegypti larval distribution. Sampling of breeding sites in coconut groves revealed that sanitation efforts were highly successful in reducing the density of fourth instar mosquito larvae (88.93 individuals/100 m2 in unsanitized groves versus 0.36 individuals/100 m2 in sanitized groves). In the sanitized groves, there were less breeding sites per nr and less larvae per breeding site. Sixty‐nine percent of the coconut‐grove larvae were found developing in rat‐chewed coconuts. Roadside samples revealed similar success of sanitation with lower fourth instar mosquito density along sanitized roadside.
Seasonal and diurnal flight activity of Circulifer haematoceps (Hom., Cicadellidae), an important leafhopper vector in the Mediterranean area and the Near East
Authors: Kersting U. , Başpmar H. 
Published: August 2009

AbstractDespite of the economic importance of Circulifer haematoceps (Mulsant et Rey) (Hom., Cicadellidae) transmitting at least three serious plant pathogens, little is known about the seasonal flight and diurnal activity of this leafhopper. Circulifer haematoceps flight activity was monitored by yellow sticky traps in first and second planting of sesame. In addition, the results of the trap captures were compared with the direct D‐VAC sampling in one sesame field. The diurnal activity was monitored over three successive days, 28–30 August, and again on 15 September by yellow sticky traps that were changed every two hours for most of the day and replaced every half hour between 05.30 h and 07.30 h and 17.30 h and 19.30 h. The yellow‐trap sampling revealed consistent seasonal activity patterns associated with both the first and second crop, characterized by a secondary maximum within the first 30 days and an absolute maximum between day 52 and 73 after sowing. Males made up > 85% of the sticky‐trap catches while females were better represented in the D‐VAC collections (74%). The diel activity was greatest between 17.30 h and 19.30 h and most concentrated within a 30 min period just before sunset. Very few individuals were captured during hours of high light intensity and during the night. During the period of greatest activity only males were trapped.
The parasite‐host relationship between Encarsia formosa (Hym., Aphelinidae) and Trialeurodes vaporariorum (Hom., Aleyrodidae) XXVI. Leaf hairs reduce the capacity of Encarsia to control greenhouse whitefly on cucumber
Authors: van Lenteren J. C. , Hua Li Zhao , Kamerman J. W. , Rumei Xu 
Published: August 2009

AbstractHost‐plant resistance and biological control are considered to be cornerstones of integrated pest management programs, but there are few studies that elucidate the intricate relationships among host plant, phytophagous insect and natural enemies. Our knowledge of interactions in systems that include three or more trophic levels is limited, yet the need for such knowledge is great. First, for understanding how selection forces shape these relationships, and secondly, for knowing how we can manipulate the systems to our benefit. Two aspects related to studies of tritrophic interactions deserve special attention for those working on biological control: (i) the incorrect assumption that host‐plant resistance always positively contributes to the suppressive effect of natural enemies, and (ii) the correct assumption that plants can be selected that promote the effectiveness of natural enemies. Examples are presented to illustrate the first point. A study of the relationships among cucumber, greenhouse whitefly [Trialeurodes vaporariorum (Westwood)] and the parasitoid Encarsia formosa Gahan illustrates the second point—selection of less‐hairy plants leads to the finding and killing of more hosts per unit of time by the parasitoid, and thus to improved biological control.
Arthropod associates of the spruce beetle Dendroctonus rufipennis (Kirby) (Col., Scolytidae) in spruce stands of south‐central and interior Alaska
Authors: Gara R. I. , Werner R. A. , Whitmore M. C. , Holsten E. H. 
Published: August 2009

AbstractThe impact of competitors, parasites and predators on spruce beetle Dendroctonus rufipennis (Kirby) broods was studied at an endemic population site near Fairbanks, Alaska, as well as at an epidemic area near Summit Lake and Cooper Landing, Alaska. Logs of white spruce, Picea glauca (Bong.) Carr., at the endemic area and Lutz spruce, Picea lutzii Little, at the epidemic site, were infested by spruce beetles. As logs became infested, associated insects were identified and their impact on the development of D. rufipennis broods evaluated. Competing Dryocoetes affaber Mann. broods were the most important interspecific mortality factor of larval D. rufipennis. The impact of dipteran and coleopteran predators and hymenopteran parasites on spruce beetle survival was of less importance than this interspecific competition.
Wound reactions of Scots pine (Pinus sylvestris L) to attacks by Tomicus piniperda L. and Ips sexdentatus Boern. (Col., Scolytidae)
Authors: Lieutier F. , Garcia J. , Yart A. , Romary P. 
Published: August 2009

AbstractBark beetles Tomicus piniperda and Ips sexdentatus were artificially inserted in Scots pines. Attacks were also provoked in other trees by attractants. Resin flow corresponding to each introduction was measured in the case of artificial insertions. In all cases, gallery length, reaction zone length and the total quantity of induced resin contained in the whole reaction were measured 5–6 weeks after insertions or attacks. The attempt of gallery construction (beginning of gallery boring) and the beginning of oviposition were also noted in each case, as well as the presence of associated fungi.Resin flow discouraged T. piniperda, but not I. sexdentatus, to attempt a gallery construction. For the two beetle species, however, it played no role after gallery boring had started. Although tree induced reaction was present during gallery elongation, at least in the case of T. piniperda, it was not clear if it played a role in stopping gallery elongation and in failure of oviposition. Few beetles were killed by resin flow or by tree reaction. The existence of oviposition was not related to attack density, tree characteristics or presence of fungi. Fungi were involved in the development of the induced reaction in response to I. sexdentatus attacks, but not in response to T. piniperda attacks. When expressing reaction zone length or resin quantity as a function of gallery length, galleries where oviposition had begun were clearly separated from those where it had not. For galleries where oviposition did not occur, reaction zone length was always correlated with gallery length for T. piniperda, and not for I. sexdentatus, but in the latter case the correlations existed when considering only galleries without fungi. Accumulation of induced resin was always correlated with gallery length for the two species. Therefore, a tree's induced reaction is not basically a defense reaction. The results corroborate the hypothesis that it is a wound reaction induced by mechanical stress due to gallery boring, and amplified by fungi when they are effective. For T. piniperda, the beetle boring activity seems to be the only way to exhaust tree response capacity.
A preliminary study on the use of trap‐trees baited with ethylene for the integrated management of the olive beetle, Phloeotribus scarabaeoides (Bern.) (Col., Scolytidae)
Authors: González R. , Campos M. 
Published: August 2009

AbstractRecent studies have established the importance of ethylene in the primary attraction of the olive beetle, Phloeotribus scarabaeoides. In light of this, two experiments were carried out in an olive grove in Granada province, Spain, these experiments utilized the increase of natural levels of ethylene produced by olive trees after the application of 2‐(chloroethyl)phosphonic acid. In the first experiment, a significant attraction of the emerging beetles for the treated trees was noted. The second experiment constitutes a first step in the use of poisoned ethylene‐baited trees in the integrated management of P. scarabaeoides. A barrier of trap‐trees sprayed with a mixture of 2‐(chloroethyl)phosphonic acid and lambda cyalothrine‐A had been set‐up along the edge of two selected plots of the olive grove. A significant reduction in the density of attacks and beetle population density has been observed in the zone located behind the barrier of trap‐trees. A decrease in the efficacy of the experimental set‐up was noted at the end of August. The factors influencing changes in density of beetle attack and population on the trees throughout the summer are discussed.
Monitoring of Helicoverpa armigera (Hbn.) by pheromone trapping in chickpea (Cicer arietinum L.)
Authors: Srivastava C. P. , Srivastava R. P. 
Published: August 2009

AbstractThe peaks in the pheromone trap catches of Helicoverpa armigera (Hübner) moths were invariably followed by the peaks in egg and larval counts (early instars) of this insect in chickpea (Cicer arietinum L.) during both years of experimentation. The correlation between pheromone trap catches of weekn‐1 and egg counts for weekn=0 were positive, r = +0.35 in 1986 and positive and significant r = +0.69 in 1987. The correlations between egg counts of weekn–1 and larval counts for weekn=0 were also significant and positive, r = +0.89 and +0.94 for the years 1986 and 1987, respectively.
Forecasting emergence and flight of some Ephestia spp. (Lep., Pyralidae) based on pheromone trapping and degree‐day accumulations
Authors: Ahmad T. R. , Ali M. A. 
Published: August 2009

AbstractForecasting system to monitor the emergence and flight activity of carob moth Ephestia calidella (Guen.), raisin moth E. figulilella (Greg.), tobacco moth E. elutella (Hüb.), and Mediterranean flour moth E. kuehniella (Zell.) in central Iraq, was established, with the aid of synthetic pheromone and relating cumulative emergence to physiological time (degree‐days, DDs). Data of moth catches indicated that the flight period occurs from early April to late November, with peaks from early May to late June, mid‐July to late August and late September to mid‐October. Data of first captures ranged from 4 April to 10 May and corresponded to a mean DD summation from 1 January of 367, 348, 608 and 453 for E. calidella, E. figulilella, E. elutella and E. kuehniella, respectively. The mean DD accumulation from 1 March was 283, 236, 496 and 350, respectively, and for E. kuehniella this allowed for a more accurate forecast of moth emergence. The regression equation governing the relationship between cumulative male capture and the DD values was determined. The usefulness of such a system is discussed in relation to control programmes.
Olfactory responses of the predatory mite Amblyseius andersoni Chant (Acari, Phytoseiidae) to bean plants infested by the spider mite Tetranychus urticae Koch (Acari, Tetranychidae)
Authors: Koveos D. S. , Kouloussis N. A. , Broufas G. D. 
Published: August 2009

AbstractThe responses of the predatory mite Amblyseius andersoni Chant adult females to odours emanating from whole bean plants or excised leaves infested by adult females of Tetranychus urticae Koch, or to possible odours from females of T. urticae were studied in the laboratory using a Y‐tube olfactometer. A. andersoni females exhibited a stronger positive response to odours from infested plants or leaves than to the uninfested ones. This preference was maintained even after the colonies of the spider mite were removed from the surface of the infested leaves and the leaves were rinsed with water. However, A. andersoni females did not show a preference for possible odours released by adult females of T. urticae or pin‐pricked uninfested leaves. These results suggest that the factor(s) motivating the selection of infested plants by the predator is probably associated with the previous infestation of the plants by the spider mite.
Adaptation of Rodolia cardinalis (Mulsant) (Col., Coccinellidae) to Icerya aegyptiaca (Douglas) (Hom., Margrodidae) as compared with Icerya purchasi Mask
Authors: Ragab M. E. 
Published: August 2009

AbstractThe Coccinellid beetle, Rodolia cardinalis (Mulsant), was introduced into Egypt in 1902 to control Icerya purchasi Mask. Developmental stages of R. cardinalis have been found to be associated with populations of Icerya aegyptiaca (Douglas) on Ficus nitida trees in the Mansoura district of Egypt. The present work throws more light on the adaptation of this predator when feeding on Icerya aegyptiaca as compared with feeding on I. purchasi. Choice of prey type was found to have a marked effect on egg coloration but appears to have no effect on hatching success or incubation period. The development of R. cardinalis larvae when reared in culture on I. aegyptiaca was significantly faster than that fed on I. purchasi. The fecundity of R. cardinalis females was not affected by the prey type consumed as adults, and although the longevity of males and females was shorter in association with I. purchasi, this difference was not significant. The results indicate that R. cardinalis is well adapted to I. aegyptiaca in Egypt.
Gamma irradiation as a disinfestation and quarantine treatment for faba bean seeds infested with Bruchus dentipes Baudi (Col., Bruchidae)
Authors: Mansour M. Y. , Al‐Bacheer M. 
Published: August 2009

AbstractA study was conducted to investigate the effectiveness of gamma irradiation as a disinfestation and quarantine treatment for faba bean seeds which contain larvae and pupae of the faba bean seed beetle, Bruchus dentipes Baudi. The results showed that a dose of 90 Gy applied to the larval stage caused 100% mortality of the treated larvae regardless of their age or instar. A dose of 300 Gy applied to the late pupal stage caused 93.8% mortality and rendered the emerged adults unable to fly. In subsequent confirmatory trials in which 100 000 infested seeds were treated, no adults emerged, which assures quarantine security to probit 9 at the 95% confidence level. Our studies indicate that ionising radiation could be an alternative to chemical fumigants for disinfestation and/or quarantine treatment of faba bean seeds infested with B. dentipes. A dose of 90 Gy applied to faba bean seeds when the pest population is still in the larval stage, during the first 3 months after harvest, is suggested. To minimise losses in seed quality, however, irradiation treatment should be done as early as possible after harvest.
Grape phylloxera, Daktulosphaira vitifoliae (Fitch) (Hom., Phylloxeridae), population response to preformed tuberosities
Authors: Omer A. D. , De Benedictis J. A. , Granett J. 
Published: August 2009

AbstractLaboratory tests were used to assess feeding and population growth of three grape phylloxera strains on preformed root tuberosities of the grape rootstock ‘AXR#1’. The tuberosities were formed on root sections by grape phylloxera biotypes A or B (first generation), after which the insects were removed and the roots were reinfested with a second cohort (second generation). Second generation phylloxera were of biotypes A or B, or a third strain, ‘SG’. Preformed tuberosities were preferentially colonized over non‐tuberosity portions of roots by all phylloxera irrespective of whether the first generation was biotype A or B. All three phylloxera types had a shorter time to maturity and a higher percentage reaching maturity when they fed on tuberosities preformed by biotype B rather than by biotype A; there was no difference in fecundities. Phylloxera also established, grew and reproduced on non‐tuberosity portions of the roots with preformed tuberosities. The time to maturity on the non‐tuberosity portions of the roots was longer and the fecundity was lower than on the preformed tuberosity portions of the same roots. After 45 days on AXR#1 roots previously infested by biotype A phylloxera, biotype A, B, and strain SG populations increased 11‐, 29‐ and 9‐fold, respectively. On roots previously infested by biotype B, the increases were 59‐, 107‐ and 44‐fold, respectively. Formation of tuberosities by phylloxera on AXR#1 increased the vulnerability of the root to subsequent attack at the preformed tuberosities, but not at other portions of the roots. Implications of these findings to population dynamics and bioassays for screening for phylloxera resistance in candidate rootstocks are discussed.