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221.
Semiochemical-based pest management programs comprise three major approaches that are being used to provide environmentally friendly control methods of insect pests: mass trapping, "lure and kill," and mating disruption. In this article, we review the potential of mass trapping in long-term pest management as well as in the eradication of invasive species. We discuss similarities and differences between mass trapping and other two main approaches of semiochemical-based pest management programs. We highlight several study cases where mass trapping has been used either in long-term pest management [e.g., codling moth, Cydia pomonella (L.); pink bollworm, Pectinophora gossypiella (Saunders); bark beetles, palm weevils, corn rootworms (Diabrotica spp.); and fruit flies] or in eradication of invasive species [e.g., gypsy moth, Lymantria dispar (L.); and boll weevil, Anthonomus grandis grandis Boheman). We list the critical issues that affect the efficacy of mass trapping and compare these with previously published models developed to investigate mass trapping efficacy in pest control. We conclude that mass trapping has good potential to suppress or eradicate low-density, isolated pest populations; however, its full potential in pest management has not been adequately realized and therefore encourages further research and development of this technology.  相似文献   
222.
Karyakartia egyptensis n. sp. (Digenea: Lepocreadiidae: Lepocreadiinae) is described from the intestine of the Jarbua terapon, Terapon jarbua (Forssk?l), collected from the Red Sea off the coast of Hurghada, Egypt. Karyakartia egyptensis n. sp. differs from K. pambanense in that the former species possesses larger spiniform structures around the perimeter of the mouth (48-54 microm as compared with 25-30 microm), a uroproct rather than ceca that end blindly or form a cyclocoel, and a somewhat smaller egg (60-68 microm as compared with 70-73 microm).  相似文献   
223.
The aim of the present study was to characterize genotypically 45 Staphylococcus aureus strains isolated from humans, bovine subclinical mastitis and food samples in Argentina by rep-PCR and PCR amplification of virulence genes. Resistances to various antibiotics could be observed for the human S. aureus, less pronounced for the bovine strains, but not for the eight S. aureus isolated from food samples. The strains could be classified genotypically by rep-PCR and by amplification of the genes encoding protein A, coagulase, clumping factor, the collagen adhesin domains A and B, capsular polysaccharide 5 and 8, the accessory gene regulator agr classes I to III, and the S. aureus gene regulator sae. rep-PCR analyses and the different gene patterns revealed that the strains could be divided into seven groups mostly matching with the origin of the isolates. The present study describes genotypic variations of S. aureus strains isolated from different origins in Argentina. The study provides a valuable insight into molecular specificities of this important pathogen.  相似文献   
224.
FtsZ is a key protein involved in bacterial and organellar division. Bacteria have only one ftsZ gene, while chlorophytes (higher plants and green alga) have two distinct FtsZ gene families, named FtsZ1 and FtsZ2. This raises the question of why chloroplasts in these organisms need distinct FtsZ proteins to divide. In order to unravel new functions associated with FtsZ proteins, we have identified and characterized an Arabidopsis thaliana FtsZ1 loss-of-function mutant. ftsZ1-knockout mutants are impeded in chloroplast division, and division is restored when FtsZ1 is expressed at a low level. FtsZ1-overexpressing plants show a drastic inhibition of chloroplast division. Chloroplast morphology is altered in ftsZ1, with chloroplasts having abnormalities in the thylakoid membrane network. Overexpression of FtsZ1 also induced defects in thylakoid organization with an increased network of twisting thylakoids and larger grana. We show that FtsZ1, in addition to being present in the stroma, is tightly associated with the thylakoid fraction. This association is developmentally regulated since FtsZ1 is found in the thylakoid fraction of young developing plant leaves but not in mature and old plant leaves. Our results suggest that plastid division protein FtsZ1 may have a function during leaf development in thylakoid organization, thus highlighting new functions for green plastid FtsZ.  相似文献   
225.
Abstract  Fuller's rose weevil (FRW; Pantomorus cervinus ) (Coleoptera: Curculionidae), a polyphagous pest of citrus and other horticultural plants, was studied in laboratory assays designed to identify potential semiochemicals from host plants that might be exploited for weevil pest management. Using still-air bioassays, weevils were found to be most attracted to fresh whole lemon leaves compared with cut and/or dried lemon leaves. White clover, an understorey plant in kiwifruit orchards, was also found to be attractive to weevils in the dual-choice tests. Coupled gas chromatography-electrophysiological recording of weevil antennal responses to commercial extracts of lemon leaves indicated that weevils detected at least eight monoterpene components of the oil, i.e. linalool, terpinen-4-ol, nerol, neral, geraniol, geranial, neryl acetate and geranyl acetate. Significant antennal dose–responses were evident to lemon leaf oil, lemon constituent odours and two major green leaf volatiles detected from clover ( Z )-3-hexenol and ( Z )-3-hexenyl acetate. Still-air dual-choice tests on individual chemicals showed significant repellency from seven of the lemon leaf compounds at 500 µg/100 µL (all except geranyl acetate). Weevils were attracted to a synthetic blend consisting of the green leaf volatiles over a range of concentrations (1, 10 and 100 mg/100 µL), as well as to clover leaves. These plant kairomone components may be potentially useful as repellents or attractants for FRW control and management programme.  相似文献   
226.
The antennal and behavioural response of three tortricid species (Lepidoptera: Tortricidae) to their corresponding sex pheromones and known or putative behavioural antagonists was tested by electroantennography and in field trials. The species and their pheromones and known or proposed behavioural antagonist were lightbrown apple moth, Epiphyas postvittana (Walker) [pheromone: 95% (E)‐11‐tetradecenyl acetate (E11‐14Ac) and 5% (E,E)‐9,11‐tetradecadienyl acetate (E9E11‐14Ac); antagonist: (Z)‐11‐tetradecenyl acetate (Z11‐14Ac)], codling moth, Cydia pomonella (L.) [pheromone: (E,E)‐8,10‐dodecadien‐1‐ol (codlemone); antagonist: (E,E)‐8,10‐dodecadienyl acetate (codlemone acetate)], and gorse pod moth, Cydia ulicetana (Haworth) [pheromone: (E,E)‐8,10‐dodecadienyl acetate (codlemone acetate); putative antagonist: (E,E)‐8,10‐dodecadien‐1‐ol (codlemone)]. In all three species, the antennal response to the antagonists was not significantly different from the antennal response to con‐specific sex pheromone compounds. In the field trapping experiments, significantly fewer males of all three species were attracted to the respective pheromone when blended with the behavioural antagonist compound. However, this response varied between the species, with lightbrown apple moth and codling moth showing stronger responses to the antagonist compounds than gorse pod moth. Both lightbrown apple moth and codling moth males were able to discriminate between pure pheromone and pheromone blended with the antagonist when placed in traps side‐by‐side separated by ca. 10 cm. The presence of the behavioural antagonist not only affected the catch of males of both species within their own traps but also affected the catch in the neighbouring trap that contained con‐specific sex pheromone; the catch of gorse pod moth was not reduced by the presence of codlemone in the neighbouring trap. These results suggest that strong behavioural antagonists such as codlemone acetate for codling moth and Z11‐14Ac for lightbrown apple moth induce their inhibition effect at a substantial distance downwind from the odour source; however, most of those males that were able to overcome this inhibition effect at the early stage of orientation to odour source, were able to discriminate between the pheromone source and the pheromone source admixed with behavioural antagonist. Moderate behavioural antagonists such as codlemone for gorse pod moth did not elicit a discrimination effect.  相似文献   
227.
Gold nanorods (GNR) within tumor microregions are characterized by their ability to absorb near IR light and emit heat in what is called photoplasmonic effect. Yet, the efficacy of nanoparticles is limited due to intratumoral tissue distribution reasons. In addition, distribution of GNRs to normal tissue might result in non specific toxicity. In the current study, we are assessing the intratumoral and tissue distribution of PEGylated GNRs on the top of its antitumor characteristics when given intravenously or intratumoral to solid tumor bearing mice and coupled with laser photoplasmonic sessions. PEGylated GNRs with a longitudinal size of less than 100 nm were prepared with aspect ratio of 4.6 showing strong surface plasmon absorption at wavelength 800 nm. Pharmacokinetics of GNR after single I.V. administration (0.1 mg/kg) showed very short systemic circulating time (less than 3 h). On the other hand, tissue distribution of I.V. GNR (0.1 mg/kg) to normal animals showed preferential deposition in spleen tissue. Repeated administration of I.V. GNR resulted in preferential accumulation in both liver and spleen tissues. In addition, I.V. administration of GNR to Ehrlich carcinoma tumor bearing mice resulted in similar tissue distribution; tumor accumulation and anti-tumor effect compared to intratumoral administration. In conclusion, the concentration of GNR achieved within tumors microregions after I.V. administration was comparable to I.T. administration and sufficient to elicit tumoral growth arrest when coupled with laser-aided photoplasmonic treatment.  相似文献   
228.
In Egypt, inflorescence brown rot disease of date plam trees caused by Thielaviopsis paradoxa De Syenes causing high losses of pollen grains and fruits yield productivity. Infection occurs early on spathes even when it still hidden in the leaf bases. White mycelium of pathogenic fungi grows on inflorescence then turned to brown when fungus spores abundant. Isolation trails from diseased spathes showed brown rot, yielded three genus of fungal i.e. Aspergillus niger (25%), Mucor hiemalis (25%) and T. paradoxa (50%). Pathogenicity test by using fungal isolates and male inflorescence of data indicate that, all isolates of T. paradoxa were able to induce brown rot of inflorescence. Isolates of T. paradoxa were differed in pathogenic activity for producing inflorescence brown rot symptom. Also, A. niger isolate could cause slightly decay on inflorescence. Meanwhile, all isolates of M. hiemalis recorded as non pathogenic. In vitro, dual culture technique by using M. hiemalis showed antagonistic properties against T. paradoxa. Scanning electron microscopy (SEM) study revealed that, pollen grains of date palm are susceptible to infection by T. paradoxa, accompanied by complete lyses and ruptured. SEM examination of inflorescence treated by each of M. hiemalis or/and T. paradoxa showed that M. hiemalis was able to colonisation on inflorescence and reduced colonisation of T. paradoxa on inflorescence and pollen grains. Preliminary evaluation of M. hiemalis as a biocontrol agent showed that, spray of inflorescence with M. hiemalis suspension two days before or after infestation by T. paradoxa were reduced brown rot of inflorescence than the control. Spraying of spathes by M. hiemalis before infestation by pathogen was highly effective in reduction brown rot incidence compared with spraying after infestation. These results help to explain the role of M. hiemalis in the suppression and biological control of T. paradoxa.  相似文献   
229.
The HPLC and spectral analyses of cysteine sulfoxides (CSOs), total polyphenols (TP), and total saponins revealed quantitative variations within the different organs of Allium nigrum L. A large accumulation of CSOs was detected in the bulb (0.367 mg/g fw), of TP in the leaf (116.05 mg CE/100 g fw), and of saponins in the root (19.38 mg/g dw). Phytochemical and chromatographical investigations of A. nigrum root extract led to the isolation of a spirostane-type glycoside or aginoside. The structure was elucidated by spectroscopic analysis (2D NMR, FABMS, HR-ESI-MS). The structure of the aginoside was identified as 25(R,S)-5α-spirostan-2α,3β,6β-trio1-3-O-β-d-glucopyranosyl-(1→2)-O-[β-d-xylopyranosyl-(1→3)]-O-β-d-glucopyranosyl-(1→4)-β-d-galactopyranoside. The highest content of aginoside, 2.9 mg/g dw, was detected in the root. The in vitro and in vivo antifungal activity of aginoside was evaluated for the first time against phytopathogens. This compound showed significant (P < 0.05) antifungal activity depending on the concentration.  相似文献   
230.
All procedures have inherent risk. Our patient endured a sequence of rare life-threatening complications from commonly preformed procedures. The sequence of these complications was; large pericardial effusion post implantable cardioverter-defibrillator (ICD) implantation with echocardiographic signs of tamponade, left main narrowing post radiofrequency ablation, and late stent thrombosis post coronary intervention with a bare metal stent. All these occurred to one unfortunate young man. Furthermore, our patient demonstrated an unintended benefit of ICD which saved his life.  相似文献   
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