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991.
Wolfram Mey 《International Review of Hydrobiology》1992,77(2):265-289
Fifty-seven species of caddisflies were identified in samples taken over a 7-month period from a large emergence trap placed on the mid-reach of a forested mountain stream in the Thuringian Forest, East Germany, in 1984. A total of 4,673 specimens were obtained during the sampling period. The community was dominated by collectors and shredders (52 % and 35.6 % of biomass) indicating a high input of allochthonous organic material from the bank trees as well as from upper stretches of the stream. The emergence periods and patterns of the common species are described and compared. Some species showed significant departures from a balanced sex-ratio. An explanation is proposed to account for the general unpredictability of sex-ratios in emergence traps. Unusual emergence patterns of 5 species are discussed in detail. 相似文献
992.
中国科学 《中国科学:生命科学英文版》2000,43(6):561-568
The phosphorylation sites of two phosphorylated proteins, bovine β-casein and myelin basic protein (MBP), were identified by high performance liquid chromatography-electrospray ionization-quadrupole ion trap mass spectrometry (HPLC-ESI-QITMS). The tryptic digest of each protein was separated by HPLC, the molecular weight of each peptide was determined by ESI-QITMS on line, and MS/MS spectrum of each peptide was simultaneously obtained by the combination of collision-induced desorption (CID) technique and tandem mass spectrometry (MS/MS) of QITMS. The phosphorylated peptide was identified by looking into whether the difference between the observed and predicted molecular weights of a peptide is 80 u or its integral multiple. Then the phosphorylation site was identified through manual interpretation of the MS/MS spectrum of the phosphorylated peptide or automatic SEQUEST data base-searching. 相似文献
993.
Abstract: The biological-control function of field boundaries of Guinea grass, Panicum maximum Jacq. on the spotted stem borer, Chilo partellus Swinhoe was examined as a reservoir for arthropod predators and as a trap plant for the pest. Field border vegetation and predator density were manipulated to determine the effect of the grass border on the abundance of stem borers and their predators in maize fields, and the effect of predators on the stem borer population. The strip of Guinea grass supported an abundance of earwigs and spiders, the potential predators of stem borer eggs and larvae. Density of C. partellus larvae in the Guinea grass strips was low throughout the season and only young larvae were collected, suggesting the inferiority of the grass stand as a habitat for stem borer larvae. These results indicate that Guinea grass is a good agent of habitat management to selectively enhance arthropod predators of stem borers and act as a sink for the pest. Predator removal resulted in a higher density of C. partellus than control in maize-bordered plots. On the other hand, no difference was found in the stem borer density between predator treatments in grass-bordered plots, probably because of insufficient predator reduction in removal plots. These results suggest that the predator assemblage found in the study site has, if sufficiently abundant, potential to limit the C. partellus population in maize fields. Even though the Guinea grass stand harboured an abundant number of predators, the grass boundaries around maize fields did not enhance predator populations within the crop field. Furthermore, field boundaries of Guinea grass had no measurable effect on the within-field density of C. partellus as a trap crop. Creating a polyculture within the crop and early planting of the grass could further enhance the biological-control function of Guinea grass boundaries. 相似文献
994.
GÁBOR HORVÁTH PÉTER MALIK GYÖRGY KRISKA HANSRUEDI WILDERMUTH 《Freshwater Biology》2007,52(9):1700-1709
1. We observed that the dragonfly species Sympetrum flaveolum, S. striolatum, S. sanguineum, S. meridionale and S. danae were attracted by polished black gravestones in a Hungarian cemetery. 2. The insects showed the same behaviour as at water: (i) they perched persistently in the immediate vicinity of the chosen gravestones and defended their perch against other dragonflies; (ii) flying individuals repeatedly touched the horizontal surface of the shiny black tombstones with the ventral side of their body; (iii) pairs in tandem position frequently circled above black gravestones. 3. Tombstones preferred by the dragonflies were in the open and had an area of at least 0.5 m2 with an almost horizontal, polished, black surface and with at least one perch in their immediate vicinity. 4. Using imaging polarimetry, we found that the black gravestones, like smooth water surfaces, reflect highly and horizontally polarized light. 5. In double‐choice field experiments with various test surfaces, we showed that the dragonflies attracted to shiny black tombstones display positive polarotaxis and, under natural conditions, detect water by means of the horizontally polarized reflected light. This, and the reflection‐polarization characteristics of black gravestones, explain why these dragonflies are attracted to black tombstones. 6. If females attracted to the black gravestones oviposit on them, the latter constitute ecological traps for dragonflies that are not close to water. 相似文献
995.
CHANG-CHI CHU EDWARD BARNES ERIC T. NATWICK TIAN-YECHEN DAVID RITTER THOMAS J. HENNEBERRY 《Insect Science》2007,14(2):165-170
An outbreak of the sweetpotato whitefly, Bemisia tabaci (Gennadius), biotype B occurred in the Imperial Valley, California in 1991. The insects destroyed melon crops and seriously damaged other vegetables, ornamentals and row crops. As a result of the need for sampling technology, we developed a whitefly trap (named the CC trap) that could be left in the field for extended time periods. We used the traps to monitor populations ofB. tabaci adults during year-round samplings from 1996 to 2002 to study variations in the weekly trap catches of the insect. The greatest number ofB. tabaci adults was recorded in 1996, followed by a continuing annual decrease in trap catches each year through 2002. The overall decline of B. tabaci is attributed in part to the adoption of an integrated pest management (IPM) program initiated in 1992 and reduced melon hectares from 1996 to 2002. Other factors may also have contributed to the population reductions. Seasonally, B. tabaci trap catches decreased during the late summer and fall concurrent with decreasing minimum tempera- tares that are suggested to be a significant factor affecting seasonal activity and reproduction. 相似文献
996.
S.J. Turner T.J.G. Martin P.B.W. McAleavey & C.C. Fleming 《The Annals of applied biology》2006,149(3):271-280
The concept of using a range of Solanaceae potato clones as trap crops for potato cyst nematode (PCN) management was investigated. A series of field trials were undertaken from 1999 to 2002 that evaluated 10 clones of either wild Solanum potato species, breeder’s hybrid lines or commercial cultivars. All had high resistance to all known PCN pathotypes (both Globodera rostochiensis and Globodera pallida) and the ability to stimulate high levels of PCN hatch. Investigations showed potential for the development of some clones as a means of reducing high PCN field population levels and for use by organic potato producers. 相似文献
997.
Sang Jae SUH Heung Chul KIM Terry A. KLEIN Sung Tae CHONG Won Ja LEE Yong Jung KWON 《Entomological Research》2005,35(3):195-198
Tabanid flies were surveyed using New Jersey light traps and Mosquito Magnet® traps at US Army installations and training sites in the northern part of Gyeonggi Province, Republic of Korea. A total of 344 tabanid flies, comprising 14 species and 5 genera, were collected from June to August during 2003‐2004. Dominant species were Chrysops vanderwulpi (57.3%), Haematopota sinensis (29.1%), Haematopota koryoensis (4.4%) and Tabanus mandarinus (2.3%). Mosquito Magnet traps that generated CO2through the combustion of propane gas were nearly 6 times more effective in collecting tabanid flies than New Jersey light traps. Based on Mosquito Magnet trap collections, peak populations occurred from mid‐June to early July.; 相似文献
998.
Control of Dacus oleae by yellow sticky traps combined with ammonium acetate slow-release dispensers
A. P. Economopoulos A. Raptis A. Stavropoulou-Delivoria A. Papadopoulos 《Entomologia Experimentalis et Applicata》1986,41(1):11-16
In an isolated olive grove of approximately 350 trees, one yellow sticky trap combined with an ammonium acetate slow-release dispenser was hung in every tree of the large fruit varieties at the end of June or beginning of July for 3 consecutive years. In September, when small fruit varieties were becoming suitable for Dacus oleae (Gmelin) infestation, similar traps were also hung in all trees of these varieties, and the traps in the large fruit trees were replaced by new ones. All traps were removed at the end of December or in January, when harvest of the olive crop was completed. The olive fly population was low in the 1st year, while in the 2nd and 3rd it was high and very high, respectively.In the 1st year, the infestation in the experimental grove was kept very low and was comparable to, or even lower, than the infestation in olive groves treated with insecticides. In the 2nd year, in most cases the infestation was between 15–30%, while in the insecticide-treated groves it remained below 10%. In the 3rd year the infestation reached levels above 80% while in the insecticide-treated groves it reached levels between 30–45%.
Résumé Un piège gluant jaune associé à un diffuseur libérant lentement de l'acétate d'ammonium, a été suspendu dans chaque arbre d'une variété à gros fruits. L'expérience a eu lieu dans une oliveraie isolée de 350 arbres environ, pendant 3 années consécutives à la fin juin et au début juillet. En septembre, quand les variétés à petits fruits deviennent convenables pour la contamination par D. oleae, des pièges sont suspendus à tous les arbres de ces variétés, les pièges sur les arbres à gros fruits sont alors remplacés. Tous les pièges sont enlevés find décembre ou en janvier, quand la récolte des olives est terminée.En 1982, les températures maximales étaient chaque semaine très élevées de mi-juin à miseptembre (33°C et plus), tandis qu'elles n'étaient atteintes en 1983 et 1984 que de fin juin à mi-août. La population de mouches de l'olive était basse en 1982, tandis qu'elle était élevée en 1983 et très élevée en 1984.La première année (à population faible) l'attaque est restée basse et était comparable ou même plus faible à celle observée dans les oliveraies traitées avec insecticides. La seconde année (population élevée) elle était le plus souvent de 15 à 30% tandis que dans les oliveraies traitées, elle restait inférieure à 10%. La 3è année (population très élevée) l'attaque atteint 80% tandis que dans les oliveraies traitées, elle était de 30 à 45%.相似文献
999.
The ultraviolet lamps commonly used in insect electrocutor traps flicker at twice the mains AC frequency. A trap was modified to be powered from a flicker-free (DC) source. When house-flies, Musca domestica L. (Diptera: Muscidae), were released in a test room containing one flickering and one non-flickering trap, 75% of the flies were caught by the trap with the flickering lamps. Mean intensities and emission spectra were identical. The trap with flickering lamps still caught more flies when the intensity of its lamps was lowered to half that of the DC-driven trap. The implications of these results for testing colour preference in attractant lamps are mentioned.
Zusammenfassung Die ultravioletten Leuchtröhren, die oft in Lichtfallen zur Bekämpfung von Fluginsekten verwendet werden, flimmern bei der doppelten Frequenz des normalen Netzwechselstromes (d.h. 100 oder 120Hz). Dieses Flimmern ist bei den Insekten, die eine hohe Flimmerlichtverschmelzungsfrequenz haben, sichtbar. Das Ziel dieser Untersuchung war, festzustellen, ob die Flimmerfrequenz die Wirksammkeit der Lichtfalle beeinflusst. Eine Rentokil (Modell 143) Lichtfalle wurde umgebaut, damit sie von zwei 12V Autobatterien betrieben werden konnte, um ein flimmerfries Anlockungslicht zu erzeugen. Stubenfliegen wurden in einem 31,8 Kubikmeter grossen Testraum, worin eine nichtflimmernde und eine unmodifizierte, flimmernde Lichtfalle montiert waren, freigelassen. Bei Versuchen, wo die normale Zimmerbeleuchtungsröhren eingeschaltet waren, wurden 75% der Fliegen in der flimmernden Lichtfalle aufgefangenen. Durchschnittswerte für Lichtintensität Beleuchtungsflächen und Ausstrahlungspektrum blieben identisch. Als dieser Versuch im verdunkelten Raum wiederholt wurde, blieben die Verhältnisse der in den beiden Fallen aufgefangenen Fliegen, unverändert. Die Fangrate der Fallen war jedoch im dunklen Raum höher, weil es keine andere für die Fliegen anlockende Lichtquellen gab. Selbst bei der Hälfte der Lichtintensität der von Gleichstrom betriebenen Lichtfalle, wurden 61% der Fliegen in der nichtflimmernden Falle aufgefangen. (Alle Versuchsergebnisse waren statistisch signifikant.) Diese erhöhte Wirksamkeit blieb für beide Geschlechter gleich. Diese Beobachtung stimmt mit den ähnlichen Flimmerfrequenzwerten von männlichen und weiblichen Art Musca überein. Im Fall der Tsetsefliege sind die beiden Geschlechter verschieden flimmerempfindlich, und deswegen würde man Unterschiede in der Reaktion auf flimmernde Lichtfallen erwarten. Von Natur aus werden Fliegen der Art Musca von flimmerden Licht angelockt. Die Konsequenzen dieser Ergebnisse hinsichtlich der Untersuchung der Farbwahl der Anlockungslichtquellen werden in diser Veröfftentlichung erwaähnt.相似文献
1000.