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Field surveys were conducted in Syria during the 2005 ⁄ 2006 and 2006 ⁄ 2007 growing seasons to identify viruses which affect cool-season food legumes, volunteer crops, and weeds with yellowing, reddening and ⁄ or stunting symptoms. Serological tests (tissue blot immunoassay) showed that Faba bean necrotic yellows virus and luteoviruses including, Beet western yellows virus, Bean leafroll virus and Soybean dwarf virus were the main viruses identified. In addition, a large number of samples reacted positively with the broad spectrum legume luteovirus (5G4) monoclonal antibody but not with any other specific luteovirus monoclonal antibodies suggesting the occurrence of new luteovirus species ⁄ strains. RT-PCR assay of 27 of such samples revealed the presence of Chickpea chlorotic stunt virus (CpCSV; genus Polerovirus, family: Luteoviridae). The coat protein nucleotide sequence analysis of the Syrian CpCSV isolate from chickpea showed a high homology (98%) to that of the Ethiopian CpCSV isolate. However, there were some differences in host range and aphid transmission characteristics between the Syrian and Ethiopian isolates. This is the first report of CpCSV naturally affecting eight legume species (Cicer arietinum L., Lens culinaris Medik., Pisum sativum L., Vicia faba L., Vicia sativa L., Vicia ervilia L. Willd., Vicia narbonensis L. and Medicago sp.) and four wild non-legume plant species [Apium sp. (Apiaceae), Euphorbia sp. (Euphorbiaceae), Physalis longifolia Nutt. (Solanaceae) and Sinapis arvensis L. (Brassicaceae)] in Syria.

Plum pox virus (PPV) symptoms were first observed in the Czech Republic in the eastern Bohemia region in the early 1940s and since then the virus has spread to the major stone fruit-growing areas. PPV is widely distributed in plums and myrobalans in both Bohemia and Moravia, excluding some regions of southern Moravia. Apricots and peaches seem to be less likely to be infected. Sporadic occurrence of PPV infection on sweet cherry trees has recently been ascertained. Wild plums and myrobalans, as well as plums growing along roads were found to be the main sources and reservoirs of PPV infection. PPV-D strain is widespread in all regions. PPV-D types appear to have been introduced earlier to the Czech Republic than Rec and M types. Formerly, a limited occurrence of PPV-M was noticed on plums, apricots and peaches. However, recent research confirmed the occurrence of a recombinant type between PPV-M and PPV-D that had been previously classified as PPV-M. So far, the presence of PPV-C strain has not been demonstrated in the Czech Republic.A study of PPV spread showed that trees in plum orchards, which had been established by planting virus free material were infected by PPV at rates fluctuating from 0 to 3% per year. In general, the fluctuations in rates of infection depended on the infection pressure of the pathogen from the surroundings. If a proportion of the planted trees were already infected, the rate of infection was much higher (up to 8%). The highest infection pressure was observed in years which were characterised by an early growing-season favoured by high temperatures at the beginning of the season. Susceptibility of plum trees to PPV infection was very significantly dependent on the age of the tree. The highest infection rates were found in three year-old trees. ? 2006 36 ? Plum pox virus in Albania

Background Fire Blight, incited by Erwinia amylovora, is one of the most damaging pear and apple diseases in the world. Fire blight was introduced to Egypt in the 1960 and threatens the Egypt’s costs for pear industry. Currently, Phage therapy is considered to be secured biological method for controlling plant bacterial diseases. This investigation aimed to isolate and identify molecularly for bacteria causing fire bright disease. As well as isolation and identification bacteriophages via spot and plaque assay techniques from pear fire blight lesions and soil. On the other hand, bacteriophages were identified based on plaque morphology, virion morphology, physical characters, profile of DNA restriction and protein. Results Pathogenicity test revealed that healthy seedlings and pear fruits were responsive to fire blight E. amylovora. Considering the relatively wide host range and greatest protein and genetic variability, using restriction enzyme pattern, the three diversity phage isolates named, EAP1, EAP2 and EAP3 showed a lack of diversity out of five were fatherly characterized. The phages confirmed the close relation of EAP1, EAP2 to Siphoviridae (hexagonal head and long flexible non-contractile tail) and EAP3 to Myoviridae (icosahedral head and contractile tail). The phages retained higher lytic competence of 90.4; 92.68 and 95.25% for EAP1, EAP2 and EAP3, respectively. The phages were stable at strong alkaline (pH 10) 2% salt solution conditions and UV spectra. While EAP3 phage revealed the hexagonal head and very short tail that belongs to Myoviridae family. Bacteriophages were characterized by digestion of the phage DNA with three restriction endonucleases and were placed into three groups based on the patterns. Bacteriophages were 9 used for reducing bacterial infection populations and severity on pear. In a bioassay, the biocontrol of E. amylovora was evaluated using disks of immature pear fruit. On the pear disk surface, bacterial exudate was considerably suppressed by all phage isolates. According to measurements of the bacterial population still present on the disk surface, phage therapy could reduce it by up to 97%. Bacteriophages reduced pear fire blight disease severity on pear fruit trails. Conclusion The results indicated that bacteriophage isolates may demonstrate variable reactivity against E. amylovora. Bacteriophages reduced pear fire blight disease severity on pear fruit trials. The results indicated that bacteriophage isolates may demonstrate variable reactivity against E. amylovora.

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