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Effective Control Measures (effective + control_measure)
Selected AbstractsRole of Alicyclobacillus acidoterrestris in the development of a disinfectant taint in shelf-stable fruit juiceLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2003N. Jensen Abstract Aims: This study was undertaken to identify the bacterium and metabolic products contributing to a disinfectant taint in shelf-stable fruit juice and to determine some of the growth conditions for the organism. Methods and Results: Microbiological examination of tainted and untainted fruit juice drinks detected low numbers of acid-dependent, thermotolerant, spore-forming bacteria in the tainted juices only. The presence of ,-cyclohexyl fatty acids was confirmed in two of the isolates by cell membrane fatty acid analysis. The isolates were subsequently identified as Alicyclobacillus acidoterrestris by partial 16S rDNA sequencing. Studies on the isolates showed growth at pH 2·5,6·0 and 19·5,58 °C. Gas chromatography/mass spectrometry (GC/MS) was used to identify and quantify 2,6-dibromophenol (2,6-DBP) and 2,6-dichlorophenol (2,6-DCP) in the tainted juice. Challenge studies in a mixed fruit drink inoculated with the two isolates and the type strain of A. acidoterrestris, incubated at 44,46 °C for 4 d, showed the production of both metabolites, which were confirmed and quantified by GC/MS. Conclusions: The results show that A. acidoterrestris can produce 2,6-DBP and 2,6-DCP in shelf-stable juices. Significance and Impact of the Study: This is the first report detailing experimental methodology showing that A. acidoterrestris can produce 2,6-DCP in foods. Control of storage temperatures (to <,20 °C) immediately after processing may provide an effective control measure for the fruit juice industry to prevent spoilage by A. acidoterrestris. [source] Review of carrot fly control in Northern Europe , 2009,EPPO BULLETIN, Issue 2 2009R. Collier In February 2009, the European and Mediterranean Plant Protection Organization (EPPO) held a workshop to discuss the management of carrot fly (Psila rosae) within Europe. Prior to the workshop, participants completed a questionnaire about carrot fly and current control methods and some of the information is summarised in this paper. In general, this pest is controlled adequately at present, but there is a heavy reliance on insecticides. The responses to the questionnaire highlighted a number of issues, in particular: the limited range and efficacy of the insecticides available at present, concerns about the availability of effective control measures in the future and a need for improvements in the targeting of treatments through forecasting and monitoring and the use of treatment thresholds. [source] Phymatotrichum (cotton) root rot caused by Phymatotrichopsis omnivora: retrospects and prospectsMOLECULAR PLANT PATHOLOGY, Issue 3 2010SRINIVASA RAO UPPALAPATI SUMMARY Phymatotrichum (cotton or Texas) root rot is caused by the soil-borne fungus Phymatotrichopsis omnivora (Duggar) Hennebert. The broad host range of the fungus includes numerous crop plants, such as alfalfa and cotton. Together with an overview of existing knowledge, this review is aimed at discussing the recent molecular and genomic approaches that have been undertaken to better understand the disease development at the molecular level with the ultimate goal of developing resistant germplasm. Taxonomy:Phymatotrichopsis omnivora (Duggar) Hennebert [synonym Phymatotrichum omnivorum (Shear) Duggar] is an asexual fungus with no known sexual stage. Mitosporic botryoblastospores occasionally form on epigeous spore mats in nature, but perform no known function and do not contribute to the disease cycle. The fungus has been affiliated erroneously with the polypore basidiomycete Sistotrema brinkmannii (Bres.) J. Erikss. Recent phylogenetic studies have placed this fungus in the ascomycete order Pezizales. Host range and disease symptoms: The fungus infects most dicotyledonous field crops, causing significant losses to cotton, alfalfa, grape, fruit and nut trees and ornamental shrubs in the south-western USA, northern Mexico and possibly parts of central Asia. However, this fungus does not cause disease in monocotyledonous plants. Symptoms include an expanding tissue collapse (rot) of infected taproots. In above-ground tissues, the root rot results in vascular discoloration of the stem and rapid wilting of the leaves without abscission, and eventually the death of the plant. Characteristic mycelial strands of the pathogen are typically present on the root's surface, aiding diagnosis. Pathogenicity: Confocal imaging of P. omnivora interactions with Medicago truncatula roots revealed that infecting hyphae do not form any specialized structures for penetration and mainly colonize cortical cells and eventually form a mycelial mantle covering the root's surfaces. Cell wall-degrading enzymes have been implicated in penetration and symptom development. Global gene expression profiling of infected M. truncatula revealed roles for jasmonic acid, ethylene and the flavonoid pathway during disease development. Phymatotrichopsis omnivora apparently evades induced host defences and may suppress the host's phytochemical defences at later stages of infection to favour pathogenesis. Disease control: No consistently effective control measures are known. The long-lived sclerotia and facultative saprotrophism of P. omnivora make crop rotation ineffective. Chemical fumigation methods are not cost-effective for most crops. Interestingly, no genetic resistance has been reported in any of the susceptible crop species. [source] Salmonella enterica serotype Virchow: epidemiology, resistance patterns and molecular characterisation of an invasive Salmonella serotype in IsraelCLINICAL MICROBIOLOGY AND INFECTION, Issue 10 2006M. Weinberger Abstract This study outlines the unique epidemiology of Salmonella enterica serotype Virchow in Israel. Between 1997 and 2002, the overall incidence of non-typhoid Salmonella enterica (NTS) decreased from 69.3 to 53.3 infections/100 000 population, but the incidence of S. Virchow increased (from 7.2 to 9.1 infections/100 000). Since 2000, S. Virchow has become the second-ranking NTS isolate, accounting for 17% and 27% of all stool and blood NTS isolates, respectively. Infants aged <,1 year had the highest incidence of isolation from stools (92.8/100 000). The incidence of isolation from blood was highest for infants aged <1 year (4.4/100 000). Only 6% of isolates were susceptible to all ten antibiotic agents tested; 34% were resistant to one agent, 54% to one to three agents, and 40% to four to six agents. A high proportion of the tested isolates were resistant to nalidixic acid (89%), streptomycin (56%), tetracycline (43%), trimethoprim,sulphamethoxazole (38%) and chloramphenicol (28%), but none to ciprofloxacin or ceftriaxone. Pulsed-field gel electrophoresis revealed two closely related clusters, each containing a predominant pulsotype. Coupled with its invasive propensity, the increasing incidence of highly resistant S. Virchow in Israel is of real concern. Future research should focus on the sources of S. Virchow in the food chain in order to institute effective control measures. [source] | ||||||||||