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A new hymenopteran aphid parasitoid species (Praon uroleucon sp. n.) fromUroleucon sp. infestingCarduus acanthoides L. is described from Yugoslavia. It is diagnosed and illustrated with scanning electron microscope photographs and line drawings. The new species is placed in thePraon dorsale species group, and a key to species of that group is provided. http://www.phytoparasitica.org posting Dec. 9, 2002.  相似文献   
3.
The role of the self-sown shrubsDittrichia viscosa (L.) W. Greuter andRubus ulmifolius Schott as reservoirs of aphid parasitoids was investigated. In the field studies conducted,D. viscosa grew adjacent to crops of durum wheat and barley andR. ulmifolius grew adjacent to cotton. The relative abundance of the parasitoids of(a) Capitophorus inulae (Passerini) onD. viscosa, (b) Rhopalosiphum padi (Linnaeus) on durum wheat and barley,(c) Aphis ruborum (Börner) onR. ulmifolius, and(d) Aphis gossypii Glover on cotton in various parts of Greece, was assessed during the years 1996–2000. In 2000, the fluctuation of parasitization of the above four aphid species was recorded and the action of the aphidophagous predators of the family Coccinellidae was studied. It was observed thatAphidius matricariae Haliday predominated onC. inulae andR. padi in all sampling cases. In contrast,Lysiphlebus fabarum (Marshall) was the dominant species parasitizingA. ruborum onR. ulmifolius andA. gossypii on cotton in Thessaly (central Greece) and Macedonia (northern Greece), whereasLysiphlebus confusus Tremblay et Eady andBinodoxys acalephae (Marshall) were the dominant parasitoid species in Thrace (northern Greece).Coccinella septempunctata Linnaeus was the most abundant coccinellid species on durum wheat, whereasAdonia variegata (Goeze) predominated on cotton. However, coccinellid individuals were scarce on bothD. viscosa andR. ulmifolius. The present study indicated that these two shrubs can be regarded as useful reservoirs of aphid parasitoids.  相似文献   
4.
Efficacy of the insecticides spinosad and methoprene, applied alone or in combination to wheat, was evaluated against six stored-product insect species, Rhyzopertha dominica, Sitophilus oryzae, S. granarius, Cryptolestes ferrugineus, Oryzaephilus surinamensis, and Liposcelis bostrychophila. The concentrations of the insecticides were 0.1 and 0.5 ppm for spinosad and 1 and 5 ppm for methoprene. Parental mortality of R. dominica was 100% on wheat treated with either rate of spinosad, with no progeny production in any combination treatment. Parental mortality of S. oryzae did not exceed 62%, and progeny production was not reduced by any insecticide treatment. All S. granarius adults exposed on wheat treated with spinosad alone at 0.5 ppm were killed, but parental mortality was reduced when methoprene was added. Progeny production was reduced in treatments containing spinosad. Mortality of adult C. ferrugineus was 97% or greater in treatments containing spinosad, but adult mortality of O. surinamensis and L. bostrychophila was not reduced by insecticide treatments. The specific combinations of spinosad and methoprene evaluated in our study would have no benefit over spinosad used alone for control of any of the six species tested.  相似文献   
5.
The objectives of this study were to assess the effects of the production systems of wheat from different production systems on the mortality, progeny production and preference of Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae). The factors tested were production system (integrated [INT], organic [ORG], biodynamic [BD] and control), which differed in plant protection and fertiliser procedures during plant growth and development; exposure interval (7, 14 and 21 d); relative humidity (r.h.) (55% and 75%) and temperature (20°C, 25°C and 30°C). Mortality after 7 d increased with the temperature increase and decreased with the increase in r.h. in most of the tested combinations. The mortality of weevils was higher in ORG compared to INT-produced wheat after 7 d. Progeny production was recorded 56 d after removal of parental adults and was higher at 75% r.h. in comparison to 55% r.h. At 55% r.h. and 20°C, progeny was 60.8% higher when S. zeamais were exposed to ORG in comparison to INT-produced wheat. Wheat from different production systems influenced mortality rates which were higher in alternative compared to INT production systems under optimal conditions for wheat storage (low temperature and r.h.). The reverse was recorded for temperature and r.h. increase. Progeny was not affected by wheat from various production systems. Significantly more S. zeamais adults were found in traps containing wheat from BD and control in comparison to INT. An understanding of the agricultural processes, biotic and abiotic factors which alter the post-harvest response of storage pests could be useful for the development of efficient post-harvest strategies for ORG and BD farms and the processing industry.  相似文献   
6.
Laboratory bioassays were carried out in order to evaluate the effectiveness of two diatomaceous earth (DE) formulations, Insecto and SilicoSec, against adults of Rhyzopertha dominica (F) in eight different grain commodities. The adherence of the two DEs to each grain was also measured. The eight grains tested were wheat, whole barley, peeled barley, oats, rye, triticale, rice and maize. These commodities were treated with the DEs at three rates, 0.75, 1.0 and 1.5 g DE kg(-1) grain. The mortality of R dominica adults was measured after 24 h, 48 h, 7 days and 14 days of exposure in the treated grains at 26 degrees C and 55% RH. After the 14-day mortality count, all adults were removed and the treated grains retained under the same conditions for a further 60 days. The treated grains were subsequently examined for F1 progeny. Significant differences were recorded among the eight grain types as well as between the DE formulations tested. After 14 days of exposure, even at the lowest DE rate for both formulations, adult mortality was high (>90%) in wheat and triticale. In contrast, adult mortality was significantly lower in peeled barley. Increasing the rate improved the efficacy of the DEs significantly in only some of the grains tested. Reproductive capacity in all the treated grains was significantly suppressed when compared with untreated grains. Generally, more F1 individuals of R dominica were noted in the treated peeled barley than in the other commodities. Significant differences in the percentage of DE retention were noted among the eight grains. The highest retention level was noted in rice (>87%) and the lowest in maize (<6%). However, the degree of DE adherence to a given grain was not always indicative of the effectiveness of DE against R dominica.  相似文献   
7.
Aphidius montenegrinus sp.n. from Serbia and Montenegro is described and illustrated. It parasitizedAcyrthosiphon daphnidis Ilharco, onDaphne alpina L. The parasitoid was described and illustrated using scanning electron microscope photographs and line drawing. The new species is a member of theAcyrthosiphon aphid parasitoid guild and was collected from Zabojsko Jezero Lake in Montenegro. The parasitoid and the hyperparasitoid spectrum ofA. daphnidis are presented for the first time. http://www.phytoparasitica.org posting April 30, 2004.  相似文献   
8.
Agrobacterium tumefaciens-mediated transformation (AMT) was used in order to create fluorescent conidia of Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales). From the fungal transformants, one Enhanced Green Fluorescent Protein B. bassiana strain indicated stability (maintained the GFP characteristics) in fluorescent signal, while its pathogenicity did not differ significantly from the wild B. bassiana type. After exposure on wheat treated with the transformed conidia, fluorescence was evident on all body parts but especially on metasternon of adults of Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) and on elytra in of Sitophilus oryzae (L.) (Coleoptera: Curculionidae). No significant differences were noted in fluorescence levels in the case of T. confusum between the transformed and the wild strain. However, the addition of diatomaceous earth (DE) increased attachment, especially at increased intervals after exposure. For S. oryzae, fluorescence of the transformed strain was decreased with the increased post-exposure time, but the simultaneous presence of DE increased fluorescence. The results of this study demonstrate that fluorescent conidia of B. bassiana can be utilized as a tool for the evaluation of parameters that affect the attachment of entomopathogenic fungi in insects?? cuticle.  相似文献   
9.
The insecticidal effects of deltamethrin, chlorpyriphos-methyl, pirimiphos-methyl, and spinosad were evaluated against adults of Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) and larvae of Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae). Spinosad was applied at 1 and 0.5 ppm, deltamethrin at 0.5 ppm, chlorpyriphos-methyl at 2.25 ppm, and pirimiphos-methyl at 4 ppm. All tests were carried out on wheat for E. kuehniella and in maize for P. truncatus, at three temperature levels, 20, 25, and 30 °C. Mortality of the exposed individuals of P. truncatus was measured after 7, 14, and 21 days of exposure, and 60 days later, the progeny production in the treated and untreated substrate was recorded. In the case of Ephestia kuehniella, mortality was assessed after 25 days. Spinosad was highly effective against P. truncatus adults, even at 0.5 ppm, but 1 ppm provided a better “speed of kill” and a higher suppression of progeny production. Mortality of the exposed P. truncatus adults after 21 days of exposure on maize treated with 0.5 ppm of spinosad was 100 %, regardless of the temperature level tested. A complete (100 %) mortality level was also noted in the case of maize treated with deltamethrin and pirimiphos-methyl, while in the case of chlorpyriphos-methyl, mortality at the 21 day exposure ranged between 61 and 90 %. Progeny production was completely suppressed only on maize treated with deltamethrin. In contrast, pirimiphos-methyl was the most effective grain protectant for E. kuehniella, since mortality was usually <99 %. In general, for both species tested, temperature had a significant effect on mortality, but this trend was different at different insecticides.  相似文献   
10.
CASE HISTORY A 3-year-old male Labrador retriever was presented with a history of dietary indiscretion followed by vomiting and abdominal pain.

CLINICAL FINDINGS AND TREATMENT: Abdominal ultrasonography revealed the presence of a fluid-filled cystic structure in the region of the pancreas. Flocculent, dark fluid was drained from the cystic structure during exploratory celiotomy prior to resection of the lateral cystic wall. Omentum was sutured into the cystic cavity to provide drainage and enhance immune response. A jejunostomy feeding tube was placed. Post-surgical care consisted of antibiotic therapy. The dog was clinically normal at 1 and 7 months post-operatively and the pancreas appeared normal on final ultrasonographic examination.

CLINICAL RELEVANCE: This case describes the use of omentum to provide physiological drainage of a pancreatic pseudocyst. This surgical technique may help clinicians manage patients with this condition in the future.  相似文献   
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