1,721,172 research outputs found
Il cancro batterico delle drupacee
No full textIl cancro batterico è una malattia ricorrente e particolarmente dannosa delle drupacee, soprattutto pesco e susino ....
Economic significance and control of bacterial spot/canker of stone fruits caused by Xanthomonas arboricola pv. pruni
No full textBacterial spot and canker of stone fruits is a multifaceted disease caused by ..
Operational Certification Manual for the Export of Lebanese Ware Potatoes
No full textPotato production is considered one of the most important in Lebanon. Potato is mainly produced in the Bekaa valley in the eastern part of the Country and in the northern Akkar plain. A big portion of potato production is consumed locally while the rest is exported to Syria, Jordan, Egypt and the gulf countries. In 2006 Lebanon signed a commercial agreement with the European Union which would allow it to export 50.000 tons of ware potatoes implemented yet for plant quarantine reasons. This ware potatoes export certification operational manual is destined to be used by field and border ware potatoes phytosanitary inspection units and inspectors to fulfill import requirements of trading partners, specifically of the European Union. The steps below describe the phytosanitary measures taken by the Plan Protection and the Export-Import and Quarantine services (TMPPO) of the Ministry of Agriculture in Lebanon to maintain Lebanese ware potatoes production free from quarantine pests of EU concern, specifically Brown Rot (Ralstonia solanacearum) and Ring Rot (Clavibacter michiganensis subsp. sepedonicus). The Plant Protection service and the Export-Import and Quarantine Service in cooperation with the Lebanese Agricultural Research Institute (LARI) are undertaking the below described measures to fulfill the import phytosanitary requirements of the European Union for ware potatoes
BIOSAFETY AND ENVIRONMENTAL CONCERNS RELATED TO THE USE OF BACTERIAL BIOCONTROL AGENTS IN CROP PROTECTION
No full textThe use of microorganisms in agriculture for the biological control of plant pathogens is increasing, due to a rising awareness among citizens for sustainability of agricultural production systems, coupled with a deeper knowledge of the relationships among the microbial communities in agricultural environments. In the EU, 54 microorganisms are currently approved for a possible use in plant protection and many more are under approval/authorization. Regulating the use of microbials in agriculture is a challenge: several countries regulate them as chemical pesticides, without taking into consideration their biological properties. Challenges might refer to: i) identification, characterization and biological properties; ii) toxicology
and environmental risks; iii) residues of microorganisms and their metabolites on food crops; iv) level of efficacy. Microorganisms may pose risks to the environment, as they are able to survive, proliferate and disseminate. Registration data requirements for biocontrol agents are currently concerning their toxicity, pathogenicity and/or infectivity. Environmental safety is assessed according a case-by-case evaluation. Mensik & Scheepmaker (2007) proposed a procedure, adopted by the OECD. The decision scheme starts with data on microbial characterization, followed by assessment on contamination/exposure in soil/surface water, together with fate and behavior of inoculum. Environmental toxicology is done on terrestrial and aquatic organisms, checking any adverse effects and, eventually, mitigation options. The environmental risk assessment terminates in “RISK ACCEPTABLE” or “RISK NOT ACCEPTABLE”. The regulatory authority may, nonetheless, consider those biocontrol agents, whose risk is assessed as “not acceptable”, if mitigation of adverse effects are possible or their use will replace a toxic pesticide
Dissemination of Pseudomonas syringae pv. actinidiae through pollen and its epiphytic life on leaves and fruit
No full textThe role of pollen in disseminating Pseudomonas syringae pv. actinidiae (Psa) in kiwifruit orchards was investigated and the survival of the pathogen as an epiphyte on leaves and fruits was followed, from pollination time until the pre-harvest season. Pollen with natural inoculum was obtained from an infected orchard and pollen harvested without any contamination by Psa was experimentally inoculated at approximately the same contamination level. Two pollination techniques were used in glasshouse experiments: dusting and spraying. In parallel, field trials in commercial orchards were carried out: two plots were designed in two orchards, where bacterial canker was present at low incidence. From petal fall to 3 weeks before harvesting, leaf and fruit samples were taken and analysed for the presence of Psa, using two different PCR protocols and direct isolation. Results confirmed the dissemination of Psa through pollen, especially when using the aqueous suspensions. Both in glasshouse experiments and in the orchards Psa was found as an epiphyte for several weeks after pollination. Pathogen populations on leaves were, initially, 10 to 100 times less than on fruitlets. As the summer continued, the epiphytic contamination levels of fruits decreased constantly, being no more detectable from early August, whereas Psa was present at detectable levels on leaves until early October, approx. 20 days before harvesting time. Our results confirmed the role of pollen in disseminating Psa, the long epiphytic survival of the pathogen on kiwifruit leaves and the increasing unsuitability of fruits to harbour detectable, epiphytic populations of the bacterium through the summer season in commercial orchards with low disease incidence, when they are reaching the final development stage. Thus, kiwifruit surfaces do not appear to be a suitable niche for a long term survival of Psa as an epiphyte and, therefore, kiwifruits should not represent a pathway for Psa dissemination and pose a negligible risk for the introduction of the pathogen into new areas
PCR-RFLP and multiplex PCR assay for the specific detection of Ralstonia solanacearum race 3/biovar 2
No full textA sensitive and reliable method for the molecular detection of Ralstonia solanacearum, race 3, biovar 2 is presented
Criticità e tecniche di controllo delle principali avversità fitosanitarie
Full text linkBacterial blight, caused by Xanthomonas arboricola pv juglandis and anthracnose, caused by the ascomycete Marssonina juglandis (teleomorph: Gnomonia leptostyla) are considered the major diseases for walnut species. Other well-known diseases of minor impact are the shallow bark necrosis caused by the Gram-negative rod Brenneria nigrifluens, the Armillaria root rot, caused by the basidiomycete Armillaria mellea and the crown and root rot, caused by a few oomycetes belonging to the genus Phytophthora. Many insect pests may also damage the crop and the main ones are the codling moth (Cydia pomonella), the walnut husk fly (Rhagoletis completa) and aphids (Callaphis juglandis e Chromaphis juglandicola). Other insect pests, defined as minor threats are: the leopard moth (Zeuzera pyrina), the carpenter moth (Cossus cossus), scales and mites
Le malattie batteriche emergenti o riemergenti delle colture agrarie in Italia e nel bacino del Mediterraneo
No full textVengono descritte alcune malattie batteriche emergenti, o riemergenti, che potrebbero diventare un serio fattore limitante le produzioni ortofrutticole italiane e mediterranee
Le batteriosi delle drupacee, un problema di non facile soluzione
No full textDa diversi anni, però, i frutticoltori italiani lamentano serie difficoltà nel mantenere la produttività degli impianti a causa di frequenti scoppi epidemici di alcune malattie batteriche che sono responsabili della comparsa di sintomi a carico dei frutti, foglie e parti legnose degli alberi
Xylella fastidiosa: il patogeno, le malattie e l’attuale situazione fitosanitaria
Full text linkXylella fastidiosa è un batterio fitopatogeno Gram negativo che appartiene alla famiglia delle Xanthomonadaceae.
È l’agente causale di numerose malattie d’importanti colture arboree, erbacee,
forestali e ornamentali e, a differenza di quanto molta parte dell’opinione pubblica crede, non è
un problema di recente comparsa, ma ha una lunga storia che affonda le sue radici ancora alla
fine del diciannovesimo secolo. L’etimologia e la semantica del nome assegnato al patogeno da
parte dei ricercatori che per primi lo isolarono in coltura pura svelano due aspetti fondamentali
della sua biologia: Xylella rivela la nicchia biologica del patogeno all’interno delle sue piante
ospiti, cioè lo xilema; fastidiosa indica la grande difficoltà che il batteriologo incontra durante il
processo d’isolamento e purificazione della coltura pura
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