bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chemical and biological investigation of harmal plant. 2. Alkaloidal investigation
Authors: El‐Gengaihi S. E. , Dimetry N. Z. , Mohamed S. M. 
Published: August 2009

AbstractAn enriched alkaloidal fraction from harmal seeds was prepared as iodide derivative, and fractionated by preparative TLC. Three compounds were obtained: harmine, harmaline and harmalol. The biological activity of the iodide derivative and the three compounds were assessed on the cotton leaf worm. Correlation between the biological activity and chemical structure was postulated.
Effect of tethering during EPG recorded probing by adults of the greenhouse whitefly
Authors: Lei H. , Tjallingii W. F. , van Lenteren J. C. 
Published: August 2009

AbstractFor electrical penetration graph (EPG) recording from a piercing insect, attachment of the insect to an electrode of thin wire is needed. The effects of tethering on the probing behaviour of the greenhouse whitefly Trialeurodes vaporariorum (Westwood) were studied by comparing free (not wired) whiteflies with tethered whiteflies, using gold wire of 10 and 20 μm diameter. As an additional group, whiteflies with silver paint contact but without wiring were used to accomplish discontinuous EPG recordings. The total probing time and the total time spent with the stylets in phloem sieve elements (phloem phase) differed between these treatments. Probing time of free insects was significantly longer than that of whiteflies wired with 20 μm, but not with 10 μm wires. Time spent in phloem phase was considerably shorter for 20 than for 10 μm wired whiteflies. These differences decreased over the 8 h experimental time. In an additional 12 h experiment, a free/tethered comparison was made on the basis of honeydew excretion, using ‘honeydew clock’ recording. By comparing the simultaneous EPGs with honeydew recordings of wired insects, a highly positive correlation was found between total duration of phloem phases and periods of honeydew excretion. Free insects spent longer time in phloem sieve elements than wired ones and shorter intervals occurred before reaching the phloem phase, which always includes phloem feeding. However, when a 2 h adaptation period was given to the wired whiteflies, an improvement could be observed in shortening the interval to the 1st phloem phase and increasing the total time of phloem phases. Although there is still an effect of a 10 μm gold wire on probing behaviour, EPG recording seems an acceptable method for investigating probing behaviour of whiteflies, as long as control whiteflies in behavioural and ecophysiological studies are tethered as well. Using an adaptation procedure to reduce the wire stress is recommended.
Spread of resistance genes in aphid populations—a simulation study
Authors: Schönfisch B. , Tomiuk J. , Wöhrmann K. 
Published: August 2009

AbstractThe model considers the spread of resistance genes in aphid populations. Two modes of aphid life cycles, a holocyclic and an anholocyclic, are simulated. Aphids are assumed to migrate from their primary host plants to two secondary host plants and vice versa causing several bottlenecks. The model studied is an one locus‐two allele model: first, it is assumed that negative selection acts against one homozygous genotype parasiting on the primary as well as secondary host. Secondly, the genotypes are assumed to be differently selected on the two secondary host plants while no selection takes place on the primary host. The model predicts a rapid spread of resistance genes in populations under conditions met in agricultural areas.
Biological activity of 1,8 cineole, a major component of essential oil of Ocimum kenyense (Ayobangira) against stored product beetles
Authors: Obeng‐Ofori D. , Reichmuth CH. , Bekele J. , Hassanali A. 
Published: August 2009

AbstractThe efficacy of 1,8 cineole as repellent, toxicant and grain protectant against Sitophilus granarius, S. zeamais, Tribolium castaneum and Prostephanus truncatus was investiaged in the laboratory using contact toxicity, grain treatment and repellency assays. 1,8 cineole applied topically or imprenated on filter paper, whole wheat as well as maize grains was highly toxic to all the four beetle species. Beetle mortality was dose‐dependent with the highest dose of 10 μl/insect evoking 100% mortalities in the beetles after 24 h exposure. 1,8 cineole was more toxic in grain than on filter paper since the lowest dosage of 0.5 μl/kg controlled all beetles exposed. There was, however, a highly significant loss of toxicity after only 24 h following treatment, irrespective of dosage applied. Development of eggs amd immature stages within grain kernels as well as progeny emergence were completely inhibited in treated grain. 1,8 cineole evoked strong repellent action against S. granarius and S. zeamais but was moderately repellent to T. castanum and P. truncatus. The protectant potential of products derived from O. kenyense against insect damage in traditional grain storage in Africa is discussed.
Host‐finding behaviour of Prostephanus truncatus (Horn) (Col., Bostrichidae): primary attraction or random attack?
Authors: Scholz D. , Tchabi A. , Borgemeister C. , Markham R. H. , Poehling H.‐M. , Lawson A. 
Published: August 2009

AbstractHost‐finding behaviour of Prostephanus truncatus was evaluated in a four‐choice olfactometer for reactions to odours of maize, cassava chips, wheat, cowpea (a non‐host plant), and woody plant species in which reproduction has been observed, and of organisms associated with maize stores. P. truncatus reacted in general to odours from starchy commodities and to some of the woody plants. Beetles did not respond to volatiles from cowpea or organisms associated with maize stores, but did react to the aggregation pheromone produced by single male P. truncatus (secondary attraction). P. truncatus raised on cassava and emigrants from maize responded as strongly to maize odours as beetles raised on maize, whereas P. truncatus trapped with pheromone traps showed reduced or no reactions. Stored commodities seem to elicit short‐range arrestment, but not primary attraction at long range. However, stored products might only be attacked facultatively by P. truncatus, co‐evolved primary attraction could possibly exist to the native host‐plant complex.
Preference and non‐preference experiments with aerial repellents againstDelia radicumL (Dipt., Anthomyiidae) in a wind tunnel
Authors: den Ouden H. , Alkema D. P. W. , Klijnstra J. W. , Theunissen J. , de Vlieger J. J. 
Published: August 2009

AbstractIn wind tunnel experiments withDelia radicumthe dosage increase efficiency of the repellent salicylaldehyde was studied under preference and non‐preference conditions. In micro field experiments in the tunnel the influence of the repellent on oviposition was measured using different application methods. A concentration of about 43 ng salicylaldehyde/l of air reduced ovipositionc.80%.
Diprionyl esters attractive to males of the dailing pine sawfly Neodiprion dailingensis Xiao et Zhou (Hym., Diprionidae) in north‐eastern China
Authors: Anderbrant O. , Zhang Q.‐H. , Chu D. 
Published: August 2009

AbstractThe attraction of male Neodiprion dailingensis Xiao et Zhou to pheromone substances identified from other Neodiprion species was tested in plantations of Pinus tabulaeformis Carr. in Liaoning Province in north‐eastern China. Both the acetate and propionate of (2S,3S,7S)‐3,7‐dimethyl‐2‐pentadecanol (diprionol) were highly attractive. An addition of 10% of the (2S,3R,7R)‐isomer did not significantly reduce the catch to the acetate. The (2S,3R,7R)‐isomer was not attractive by itself. This is the first pheromone study of a species belonging to the recently described East Asian group of Neodiprion. The response of N. dailingensis males is similar to that of N. sertifer males in eastern part of Asia.
Migration in spruce bark beetles (Ips typographis L.) and the efficiency of pheromone traps
Authors: Duelli P. , Zahradnik P. , Knizek M. , Kalinova B. 
Published: August 2009

AbstractMark‐release‐recapture experiments with both newly emerged and flight experienced Ips typographus L. were performed in a pine forest near Prague. Three concentric trap circles around the release site with a radius of 5 m, 200 m and 500 m, and intertrap distances of 6 m, 16 m and. maximally, 40 m, were installed with the intention of collecting all dispersing bark beetles ready to respond to pheromone lures. The results show that even without wind and no potential host trees in the surroundings, only about one‐third (35.4%) of the emerging beetles in an infested site can be eliminated locally with phermomone traps. At least 12.2% of the emerging beetles (25.7% of the recaptures), perform an adaptive migration flight, which brings them beyond the range of local pheromone traps. The estimated proportion of emigrants can rise over 50%, if most of the freshly emerged beetles that have never been recaptured are assumed to have left the experimental area. Electroantennograms recorded in the laboratory at different times after emergence indicate that the delayed response to aggregation pheromones in migrating bark beetles is not the result of a delayed maturation of the antennal receptor cells, but obviously governed by the central nervous system. The notion of precopulatory migration in 25–50% of the individuals in an I. typographus population can explain why pheromone traps can never eliminate all emerging beetles, and why so many bark beetles can be collected far away from any breeding sites.
Preference for sites within plant by larvae of the cabbage webworm, Hellula undalis (Fabr.) (Lep., Pyralidae)
Authors: Sivapragasam A. , Chua T. H. 
Published: August 2009

AbstractA comparative study on the cabbage webworm (CWW), Hellula undalis, with respect to larvae feeding either on the shoot or leaf of cabbage was carried out both in the laboratory and in the field. For the first 2 days after eclosion from the egg, a CWW larva would tend to remain within the mine in the leaf where the egg was deposited. The Lloyd patchiness index (x*/x) suggested that the larval distribution was contagious, although the degree of contagiousness tended to decrease as the larvae grew due to their dispersal movement. This was indicated by the inter‐plant larval movement study, in which most of these larvae were found in the shoot: 84.6% on the source plant and 40% on the neighbouring plants by the ninth day of experiment. For the larvae that fed on the shoot, the duration of the larval and pupal stages were significantly shorter and adult longevity was significantly longer, although the females laid a significantly lower number of eggs than those from larvae that fed on the leaves. However, there were no differences in the size of adults reared either on the shoot or the leaves (body lengths were 7.96 ± 0.12 and 7.82 ± 0.08 mm, respectively), and in the survivorship patterns of the adults. The moths emerging from larvae collected from the cabbage shoot in the field also lived slightly longer but laid fewer eggs than those from the leaves, with the intrinsic rate of increase (rm) of 0.11 and 0.07, respectively. The results indicated that the CWW larvae preferred the cabbage shoot (to the leaves) which provides a natural refuge and protection for the CWW larva under field conditions, although it is relatively a poorer food type (3.47 ± 0.17% nitrogen) than the leaf (4.31 ± 0.30% nitrogen) (P < 0.05). The higher fertility of CWW bred from the leaves could possibly be related to the relatively higher percentage nitrogen in the leaves. After eclosion from the eggs, there was initial grouping of larvae in the shoot, and then an eventual decrease which could be due to the limited carrying capacity of the shoot to accommodate more than one larva.
Occurrence of immature stages of olive psyllid Euphyllura phillyreae (Hom., Aphalaridae) in Phillyrea latifolia and Olea europaea in coastal northern Greece
Authors: Prophetou‐Athanasiadou D. A. 
Published: August 2009

AbstractThe occurence of immature stages of olive psylla, Euphyllura phillyreae Foerster on olive trees (Olea europea) and Phillyrea media in northern Greece was studied during the years 1989/90. E. phillyreae, which infests olive trees and Phillyrea latifolia (P. media) in Greece, is univoltine and has an aestival–autumnal–hibernal reproductive diapause as an adult. Immature stages and adults were collected from January 1989 through December 1990 from two groups of P. latifolia, differing in vigour and time of blooming, and from olive trees. On olive, the first eggs were observed on early April. On Phillyrea, eggs were deposited much earlier than on olive. Egg laying was related to host phenology. As the eggs were laid during certain growth stages of the host plant, the various larval instars were also synchronized with certain growth stages of the plant. Therefore, the oviposition and the occurrence of larval stages differ between the three host plants tested and coincide with the proper stage of growth of each plant group. The period from oviposition to adult emergence was longest (3 months) on Phillyrea 1, shorter (2 months) on Phillyrea 2 and shortest (1.5 months) on olives.
Laboratory evaluation of control of the European corn borer, Ostrinia nubilalis (Hb.) (Lep., Pyralidae) by nematodes of the genus Steinernema (Nematoda, Steinernematidae) at low temperature
Authors: Eculica J. F. , Bečvář S. , Mráček Z. , Kindlmann P. 
Published: August 2009

AbstractCold active isolates #76, #102, and #D of Steinernema kraussei and the Czech isolate #B1 of S. feltiae pre‐adapted for the parasitation of European corn borer, Ostrinia nubilalis, were used for the laboratory control of the European corn borer larvae and pupae at low temperature. The experiments performed in Petri dishes were divided into two alternatives, both at a constant temperature of 7°C, exposition time 250 h with 200 infective juveniles and 10 insects per dish. In the first experiment the only non‐ligatured Ostrinia larvae and Canadian isolates were tested, while in the second experiment the Canadian isolate #D and Czech isolate #B1 were compared when using against ligatured larvae of the pest. The average mortality of the pest larvae in the first experiment reached maximally 26% and the average number of adult nematodes recovered by dissection was 7.2 per insect in the best #D isolate. Low efficacy of steiner‐nematids to pest larvae was probably significantly influenced by forming a cocoon by insect. In the second experiment the pest larvae were ligatured before nematode application and forming of the cocoon was blocked. Surprisingly, the #B1 isolate killed on average 88.3% of Ostrinia larvae while the cold active #D isolate killed only 48.3% of the pest larvae. Number of recovered adults per insect by dissection was 30.3 in the #B1 isolate and 10 in the #D isolate. The results were analysed by means of one‐way analysis of variance and of t‐test. The percentage of parasitation (P < 0.01) and number of recovered adults (P < 0.05) were statistically significant between S. kraussei #D and S. feltiae #B1. It is speculated that the adaptability of the #B1 isolate had more significant role for the parasitation than the cold activity of the #D isolate.
Comparison of different trapping methods in Agromyzidae (Diptera)
Authors: Scheirs J. , De Bruyn L. , von Tschirnhaus M. 
Published: August 2009

AbstractTrapping techniques are frequently used to monitor pest species. These trapping techniques have to provide reasonably precise estimates of densities and sex ratios of monitored species in order to apply appropriate insect pest control measures most efficiently. A broad range of trapping methods are applied to gather this basic ecological information. However, few studies question the reliability of trapping methods to obtain accurate data. Here, we investigate the usefulness of traps for the assessment of basic life‐history data in Agromyzidae. In this study, Malaise traps and coloured water traps are compared. Significant deviations of a 1♂: 1♀ sex ratio occurred both in Malaise and colour traps. The bias of these deviations of the sex ratio altered according to the trapping method. In the Malaise traps most significant deviations were female biased. All significant deviations observed in the colour traps were male biased. The overall sex ratio of all captured individuals was in every Malaise trap in favour of the females and in every colour trap in favour of the males. Different trapping methods also revealed intraspecific differences in phenology patterns. Agromyzid flies were trapped earlier in colour traps compared to Malaise traps. Possible explanations for the observed intraspecific differences in sex ratio and phenology pattern between traps are discussed. This study points out that a thorough analysis of the response of a target species to a certain trapping method is needed in order to ascertain the reliability of the collected data. The importance and consequences of these results for monitoring agromyzid pest species are emphasized.
Changes in fecundity of Rhodnius prolixus Sål (Het., Reduviidae) caused by three nucleoside derivatives
Authors: Gelbič I. , Soldán T. 
Published: August 2009

Abstract(R,S)‐(2,3‐dihydroxypropyl)adenine, 9‐(2‐phosphonylmethoxyethyl)adenine and D‐eritadenine injected at 0.001–1% concentrations into female flight muscles of Rhodnius prolixus significantly affected their reproduction. Both germarium and vitellarium showed pycnotic cells and degenerative changes of trophic syncytium. Some follicles were vacuolated or invaginated with at least partially resorbed oocytes. Eggs were laid irregularly, the average number of eggs per female per day was 0.83–3.30 (4.45 in controls) and their weight was 10–30% lower. Hatchability of treated females reached 42–67% compared to 84.6% in controls. Changes in Rhodnius prolixus reproduction were dose‐dependent with all compounds studied. D‐eritadenine was an order of magnitude more effective than remaining compounds studied. Fecundity recovered within 3–4 weeks following treatment.
Relative effect of different host feeding site on long‐range host location and electroantennogram response in the parasitoid Cotesia glomerata (Hym., Braconidae)
Authors: Coleman R. A. , Barker A. M. , Fenner M. , King F. C. 
Published: August 2009

AbstractThe effect of host feeding site on the potential host‐finding success of the parasitoid Cotesia glomerata was investigated in the tritrophic system Brassica oleracea L. ‐ Pieris brassicae L. (Lep., Pieridae) ‐ Cotesia glomerata L. (Hym., Braconidae). The parasitoids were found to be most attracted to plants with herbivores feeding on upper foliage, less attracted by mid‐plant herbivory and incapable of distinguishing between control plants and plants with herbivory on the lowest leaves. In EAG tests there was no difference in response with respect to volatiles from damage at different levels on the plant. The possible ecological significance of these results are discussed in relation to predicted models of wound‐induced defence and olfactory neurological coding.
Biotypes of the castor bean whitefly Trialeurodes ricini (Misra) (Hom., Aleyrodidae) in Egypt: biochemical characterization and efficiency of geminivirus transmission
Authors: Idriss M. , Abdallah N. , Aref N. , Haridy G. , Madkour M. 
Published: August 2009

AbstractThe newly introduced castor bean whitefly (CBW) Trialeurodes ricini (Misra) has become an important pest which is widely spread all over Egypt. Biochemical studies were conducted to distinguish the different T. ricini biotypes and to determine the biotype economic threshold based on its ability to transmit plant viruses. Forty‐five samples of T. ricini adults were collected from castor bean (Ricinus communis) at different geographical locations representing the Egyptian Delta and Nile valley governorates. Esterase banding patterns were investigated to evaluate the extent of variation among the tested populations of the castor bean whitefly. Electrophoresis of homogenates of individual T. ricini females showed that there are five different biotypes (C1–C5). The predominant biotype (C1 type) was found in about 80% of the tested locations. In transmission studies, the polymerase chain reaction (PCR) was used to detect geminiviruses in nucleic acid extracted from the different castor bean whitefly biotypes. PCR revealed that the five biotypes of T. ricini are viruliferous. To evaluate the efficiency of the predominant T. ricini biotype for transmitting the tomato yellow leaf curl virus (TYLCV), acquisition and inoculation access periods were determined. PCR indicated that 50% of whitefly adults collected from castor bean, acquired the virus after 10 h exposure to TYLCV infected tomato. Experimentally, the rate of transmission increased as the inoculation access period was lengthened and reached a maximum after 4 h. The obtained symptomatological results were also confirmed by PCR.
Neue Zuchtmethode für Tipula paludosa und Tipula oleracea (Dipt., Tipulidae) und Beobachtungen zur Entwicklung der Laborpopulationen
Authors: Szewezyk D. , Langenbruch G. A. 
Published: August 2009

Abstract: A new rearing method for Tipula paludosa and Tipula oleracea (Dipt., Tipulidae) and some records on the development of the laboratory population. The previously complicated and labour‐intensive rearing of Tipula spp. has been considerably simplified. The imagines of both sexes are kept in a cage for egg‐laying. The food used is a solution of cane sugar, which attracts at the same time the females. In the direct neighbourhood of the food source, petri dishes are placed, which are filled with moist, marshy soil. The females lay their eggs there. The neonate larvae remain in those dishes, which are then covered. The larvae are fed with fresh plant material, and, later on (mostly in the second instar) are moved into larger dishes. After the third instar the larvae become negative phototactic and live in the ground. Therefore they can be kept in open boxes in a large cage. These rearing boxes are filled with soil, into which two stripes of grass has been sown. The bare soil between the stripes is covered with various plant material. Pupation and emergence of the adults takes place also in those boxes.During these studies the food preferences of the laboratory strains have been determined, and some details of the Tipula‐development recorded.ZusammenfassungDie bisher komplizierte und arbeitsaufwendige Zucht von T. paludosa und T. oleracea wurde wesentlich vereinfacht: Die geschlüpften Imagines beider Geschlechter werden in einem Eiablage‐Käfig gehalten. Als Nahrung dient eine Rohrzuckerlösung, welcher gleichzeitig eine Lockfunktion für die Weibchen zukommt. In unmittelbarer Nähe dieser Lösung befinden sich mit anmooriger, feuchter Erde gefüllte Petrischalen. damit die Weibchen darin ihre Eier ablegen. Die frischgeschlüpften Larven verbleiben in diesen, nach dem Schlupf abgedeckten Schalen, werden mit frischen Pflanzen gefüttert und im Laufe ihrer weiteren Entwicklung in größere Schalen umgesetzt. Ab dem dritten Stadium bleiben die jetzt phototaktisch negativ eingestellten Larven im Boden und können deshalb in einem großen Käfig in offenen Schalen gehalten werden. Diese Pflanzschalen sind mit heranwachsendem Gras und ausgelegten Blättern verschiedener Pflanzenarten bedeckt. Darin erfolgt auch die Verpuppung und das Schlüpfen der Imagines.Während der Erarbeitung dieser Zuchtmethode wurden Fraßpräferenzen der Laborpopulation festgestellt und einige Einzelheiten der Tipula‐Entwicklung festgehalten.