In the spring of 2004, severe outbreaks of a disease resembling citrus blast (Whiteside et al ., 1988), were observed on trees of orange ( Citrus cinensis cv. Washington) and mandarin ( Citrus rediculate cv. Marisol) in the Turkish Mediterranean regions of Adana and Antalya. Characteristic disease symptoms were first seen on leaves as watersoaked lesions and black areas on the petiole wings. Later lesions extended to the mid-vein of leaves and to the twigs surrounding the base of the petiole. Finally, the leaves dried and rolled, while still firmly attached, before eventually dropping without petioles. The necrotic areas on twigs further enlarged and the twigs were eventually killed within 20 -30 days. The damage was serious in a 50-hectare citrus orchard in Antalya, with a disease incidence of nearly 100%. Twelve isolates of a bacterium, consistently isolated from infected leaves, petioles and twigs, which formed fluorescent colonies on King's medium B, were purified and used for further studies. All isolates were Gram-, oxidase-, pectolytic activity-, starch hydrolase-, arginine dihydrolase-and nitrate reduction-negative; and levan-, gelatin hydrolase-positive. They produced hypersensitive reactions (positive) on tobacco leaves ( Nicotiana tabacum cv. Samsun N.). All produced acid from glucose, glycerine, arabinose, mannitol, sorbitol, sucrose and xylose but not from lactose and maltose. The test results conformed to the characteristics of P. syringae pv. syringae (Braun-Kiewnick & Sands, 2001) as the causal organism of citrus blast and were similar to those of reference strain NCPPB 2307 of P. syringae pv. syringae used in this study. Fatty acid analysis (Atatürk University, Erzurum, Turkey) confirmed the bacterial strains as P. syringae pv. syringae with similarity indices of 81-94%.Pathogenicity of the strains was tested on 1-year-old mandarin. Inoculations were made, using a hypodermic needle with a suspension of bacteria in a saline buffer (10 8

A virus was recovered by sap transmission from plants of several citrus species exhibiting or not symptoms of chlorotic dwarf (CCD), a disease recently reported from Eastern Mediterranean Turkey. The virus was identified as an isolate of olive latent virus 1 (OLV-1), originally described as a possible sobemovirus. The citrus isolate of OLV-I (OLV-1/Tk) possesses biological, morphological, physico-chemical, and ultrastructural properties similar, if not identical to those of the OLV-1 type strain and is also serologically indistinguishable from it. In addition, OLV-1/Tk has many properties, especially physico-chemical, in common with serotypes A and D of tobacco necrosis necrovirus (TNV-A and TNV-D). However, OLV-1/Tk is only very distantly related serologically to both TNV-A and D, suggesting that it can be regarded as a distinct species in the genus Necrovirus. OLV-1/Tk could not be detected in citrus tissues by ELISA or dot-blot molecular hybridization, probably because of the extremely low virus concentration. By contrast, limited virus recovery was obtained by sap inoculation and fair detection rates were afforded by PCR. OLV-1/Tk was identified in 54 of 92 (59%) citrus plants affected by CCD and in 14 of 49 (28%) symptomless plants. These results do not support the notion that there is a canse-effect relationship between OLV-1/Tk and CCD, even though the more frequent association of this virus with diseased plants remains intriguing.

Garlic (Allium sativum L.) is one of the most important Allium spp. plants that are widely cultivated throughout the world. A significant reduction in yield and quality due to virus infection is now a serious economic problem (1). In many cases, garlic plants are infected with a variety of viruses, but elimination of these viruses is difficult because this crop is propagated through bulbs. Potyviruses, carlaviruses, and allexiviruses have been detected in diseased garlic. Onion yellow dwarf virus (OYDV) and Leek Yellow Stripe Virus (LYSV), genus Potyvirus, family Potyviridae, are two important viral pathogens of garlic. Virus diseases of garlic are widespread in the world, causing serious damage to yields and quality of the crop. The East Mediterranean Region produces 14% of the garlic production of Turkey (110,000 t). A survey was done in garlic fields in Adana, Mersin, Kahramanmaras, Hatay, and Gaziantep provinces of Turkey where virus-like symptoms were noted in samples collected during the 2007–2008 growing season. Leaf and bulb samples were taken from 202 plants with leaf yellow stripe, mosaic, enations, and deformation or dwarfism symptoms. ELISA was performed with antibodies from Agdia (Elkhart, IN). Results indicated that 57 samples (28.2%) were infected with OYDV and 43 samples (21.2%) were infected with LYSV. In addition, 23 samples were determined to be infected by both viruses. All ELISA-positive samples and 10 ELISA-negative samples were analyzed by reverse transcription-PCR with primers 1OYDV-G (5′ TTA CAT TCT AAT ACC AAG CA 3′) and 2OYDV-G (5′ GCA GGA GAT GGG GAG GAC GC 3′) for the detection of OYDV and primers 1LYSV (5′ TCA CTG CAT ATG CGC ACC AT 3′) and 2LYSV (5′ GCA CCA TAC AGT GAA TTG AG 3′) for the detection of LYSV. These primers were previously reported to be specific for the coat protein genes of OYDV and LYSV, respectively (2). Products of the expected size (774 bp for OYDV and 1,020 bp for LYSV) were amplified only from the ELISA-positive samples of the respective viruses, confirming infections by OYDV and LYSV. To our knowledge, this is the first report of OYDV and LYSV in garlic in Turkey. References: (1) L. Bos et al. Neth. J. Plant Pathol. 84:185, 1978. (2) T. V. M. Fajardo et al. Fitopatol. Bras. 26:619, 2001.

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