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The distribution of olive fruit fly captures with McPhail traps within an olive orchard 总被引:1,自引:0,他引:1
Ioannis?DimouEmail author Constantin?Koutsikopoulos Aristidis?Economopoulos Josef?Lykakis 《Phytoparasitica》2003,31(2):124-131
The spatial distribution of olive fruit flyBactrocera (Dacus) oleae (Gmelin) (Diptera: Tephritidae) field captures with McPhail traps within an experimental orchard was evaluated. Contour maps
were constructed to examine the patterns in the 3-year trapping data. Captures varied widely inside the olive orchard, with
traps suspended on wild olive trees exhibiting the poorest performance. Favorable microclimate, created by a standing water
pool, appeared to be responsible for increased trap captures during the hot summer months. The positive role of the olive
tree fruit load is also discussed.
http://www.phytoparasitica.org posting Feb. 2, 2003. 相似文献
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The field efficacy of a bait containing phloxine B, uranine and Provesta 621 protein was tested against Mediterranean fruit fly (Ceratitis capitata; Medfly) by aerial and ground spraying in about 84 ha of coffee fields in Kauai, Hawaii, USA. Concurrently, soil and crop samples were collected from the aerially sprayed field and its unsprayed control field for residue studies. Efficacy of the sprays was assessed through trapping with both protein-baited and trimedlure-baited traps and through the infestation level of coffee cherries collected at least three-quarters ripe. The C capitata population was low at the start of the aerial and ground spray studies, but dramatically increased in the control fields. This increase coincided with initial ripening of coffee cherries. During times of peak population levels, C capitata populations were reduced by more than 91% in the ground-sprayed field and 99% in the aerial-sprayed field, relative to the populations in their respective control fields and based on protein-baited trap catches. Results of residue analyses indicated that uranine dissipated quickly compared with phloxine B on coffee and soil. Coffee samples collected at pre-spray periods had phloxine B residues of 7.2-25.5 ng g-1 on berries. Phloxine B concentrations were much higher on coffee leaves (163-1120 ng g-1). Lower concentrations of the dye were found from coffee samples collected during rainy days. Average phloxine B concentrations immediately after spraying were 56 and 2840 ng g-1 in coffee berries and leaves, respectively. Dissipation of phloxine B on berries was fast, with a half-life (t1/2) of 3 days. Dissipation of phloxine B on leaves was fitted to two linear phases: the initial (0-4 days) with a shorter t1/2 of 3 days and the later phase (4-28 days) with a longer t1/2 of 15 days. Average concentrations of phloxine B in the top soil ranged from 50 to 590 ng g-1 at pre-spray. Phloxine B initial concentration (770 ng g-1) reached a plateau immediately after the last spraying, but showed a steady decline over time with t1/2 of 16 days. Fast dissipation of the dyes in the field indicates that these chemicals may be environmentally compatible and therefore a promising alternative for fruit fly control. 相似文献
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John H. Rossmeisl Jr. DVM MS DACVIM Michael A. Higgins DVM Dennis J. Blodgett DVM PhD DABVT Matthew Ellis DVM Delbert E. Jones MS 《Journal of Veterinary Emergency and Critical Care》2006,16(3):208-214
Objective: To report the manifestations, history, and pathophysiologic basis of disease in 2 dogs with Amanita muscaria toxicosis. Case summaries: Two dogs were evaluated for an acute onset of gastroenteritis and seizures. A. muscaria toxicosis was suspected in each dog after confirmation of environmental exposure and visualization of ingested mushrooms in vomitus. The diagnosis was confirmed following identification of toxic Amanita metabolites in the urine and serum of each dog. Administration of supportive and symptomatic therapies resulted in the complete recovery of each animal. Unique information provided: Ingestion of the mushroom, A. muscaria, by dogs can result in acute gastrointestinal distress that precedes a potentially life‐threatening central neurologic syndrome characterized by seizures, tremors, and somnolence. Central nervous system dysfunction results primarily from the actions of ibotenic acid and its decarboxylation product, muscimol, which are analogues of the neurotransmitters glutamate and γ‐aminobutyric acid (GABA), respectively. Identification of these toxins in the urine and serum of affected dogs using high‐performance liquid chromatography (HPLC) provides a definitive diagnosis. 相似文献
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Andrew Y. Li Felix D. Guerrero John H. Pruett 《Pesticide biochemistry and physiology》2007,87(2):147-155
Resistance to insecticides remains a major problem for the successful control of the horn fly, Haematobia irritans irritans (L.), one of the most important pests of cattle in many countries including the United States. The organophosphate (OP) insecticide diazinon has been used to control pyrethroid-resistant populations of the horn fly. There are only a few reported cases of horn fly resistance to diazinon in the United States and Mexico. Piperonyl butoxide (PBO) has been used successfully as a synergist of pyrethroid insecticides to control horn flies. PBO-synergized diazinon products are also available for horn fly control in the United States, although PBO is known to inhibit the bio-activation of certain OP insecticides including diazinon. A study was conducted to evaluate the effect of PBO on diazinon toxicity to horn flies using a filter paper bioassay technique. These bioassays in both the susceptible and diazinon-resistant horn fly strains revealed a biphasic effect of PBO on diazinon toxicity to horn flies. PBO inhibited diazinon toxicity when the PBO concentration used was high (5%), and no effect was observed when PBO concentration was intermediate (2%). However, at low concentrations (1% and lower), PBO significantly synergized diazinon toxicity. We demonstrated that enhanced esterase activity was associated with survivability of horn flies exposed to diazinon alone. PBO has been shown to inhibit esterase activity in other insect species. However, results of biochemical assays with esterases from this study suggest that PBO did not have significant effect on the overall esterase activity in the horn fly. The observed synergistic effect of PBO at lower concentrations on diazinon toxicity to horn flies could not be explained by reduced esterase activity due to PBO inhibition. It is likely that PBO synergized diazinon toxicity at lower concentrations by facilitating penetration of diazinon through the cuticle and/or inhibiting the oxidative detoxification of diazinon, and reduced diazinon toxicity at high PBO concentration by inhibiting the bio-activation of diazinon. 相似文献
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选用果蝇作实验动物,通过余甘原汁、余甘粉和余甘营养液对果蝇寿命影响的研究表明,在一定的浓度范围内,余甘子的3种产品都能延长果蝇寿命,尤其是25%浓度余甘营养液能使果蝇平均寿命比对照延长1倍以上,从而进一步验证了余甘果的抗衰老作用。 相似文献