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Aims: In this study, the best sampling time and tissues for phytoplasma detection in twenty pear trees (cv. Deveci) infected by ‘Candidatus Phytoplasma pyri’, causal agent of pear decline disease, in Bursa province of Turkey were investigated. Methods and Results: Sampling was done throughout the year in leaf midribs, shoot and root tissues, where as the flower tissues were tested once a year in March and fruit tissues in September. All samples were analyzed by nested-PCR using P1/P7 and fU5/rU3 universal primer pairs. Nested PCR products were digested with RsaI and SspI restriction enzymes. The results revealed that the detection rate of ‘Ca. P. pyri’ in different plant tissues was greatly depending on the sample collection period. The fruit tissues, which were only sampled in September due to the ripening time of Deveci pear cultivar in Bursa, showed the highest detection rate of ‘Ca. P. pyri’ (100%) followed by flower tissues (75%). The average detection rate in root, shoot tissues and leaf midribs was found as 43.75, 39.58 and 16.25%, respectively. The present results showed that the best plant tissues for detecting ‘Ca. P. pyri’ in pear trees were fruit columella and flowers. The highest detection rate of this phytoplasma in root tissues was found from November to March, whereas it could be detected whole year around except summer months in shoot samples in Turkey. Conclusions: For 'Candidatus Phytoplasma pyri', detection, if there is no seasonal limitation for testing, the most suitable tissues are fruits and flowers. When it comes to testing throughout the year, the most suitable tissues were determined as the root, the phloem and cambium layer of the shoots and the leaves, respectively. Significance and Impact of the Study: This study on seasonal variations of ‘Candidatus Phytoplasma pyri’ in different pear tissues has been first time investigated in Turkey. This preliminary data provides important knowledge on molecular detection of Ca. P. pyri, causal agent of pear decline disease for further studies and sertification-quarantine programmes of pear trees in Turkey., Amaç: Bu çalışmada, ülkemizde Bursa ilinde saptanmış olan armut yıkım fitoplazması (‘Candidatus Phytoplasma pyri’, PD) ile enfekteli 20 armut ağacı (Deveci çeşidi) seçilerek etmenin teşhis edilmesinde en uygun örnekleme zamanı ve bitki dokusunun belirlenmesi amaçlanmıştır. Yöntem ve Bulgular: Yaprak, sürgün ve kök dokularında yıl boyunca örnekleme yapılırken çiçek dokuları Mart ayı, meyve dokuları ise Eylül ayında olmak üzere yılda bir kez testlenmiştir. Tüm örnekler P1/P7 ve fU5/rU3 üniversal primer çiftleri kullanılarak nested-PCR yöntemiyle analiz edilmiştir. Nested-PCR ürünleri RsaI ve SspI restriksiyon enzimleri ile kesime tabi tutulmuştur. Elde edilen sonuçlara göre farklı bitki dokularında ‘Ca. P. pyri ‘nin saptanma oranının büyük ölçüde örnek toplama peryoduna bağlı olduğunu ortaya koymuştur. Bursa ili koşullarında Deveci armut çeşidinin olgunlaşma dönemine göre sadece Eylül ayında örneklenen meyve dokularınde yüksek oranda ‘Ca. P. pyri’ tespit edilirken (% 100), bunu çiçek dokuları (%75) izlemiştir. Kök, sürgün ve yapraklarda ortalama tespit oranı sırasıyla % 43.75, 39.58 ve 16.25 olarak bulunmuştur. Elde edilen sonuçlar armut ağaçlarında ‘Ca P. pyri’ nin saptanması için en iyi bitki dokularının meyve kolumellası ve çiçek olduğunu göstermiştir. Bu fitoplazmanın kök dokulardaki en yüksek tespit oranı Kasım-Mart ayları arasında bulunurken, ülkemizde sürgün örneklerinde yaz ayları hariç bütün yıl tespit edilebildiği belirlenmiştir. Genel Yorum: 'Candidatus Phytoplasma pyri'nin testlenmesi için mevsimsel açıdan bir sınırlama olmaması durumunda en uygun dokular meyve ve çiçekler olup yıl boyunca testleme yapılması söz konusu olduğunda ise sırasıyla en uygun dokular kök, sürgünlerin floem ve kambiyum tabakası ve yapraklar olarak belirlenmiştir. Çalışmanın Önemi ve Etkisi: Farklı armut dokularında 'Candidatus Phytoplasma pyri' varlığının mevsimsel dağılımı konusunda yapılan bu çalışma ülkemizde ilk kez yapılmıştır. Elde edilen veriler, Türkiye’de armut ağaçlarında sertifikasyon-karantina programları için ve armut yıkım fitoplazmasının etmeni Ca. P. pyri’nin moleküler tespiti konusunda önemli bilgiler sağlamıştır.

Sharka is the most damaging viral disease ofPrunusspp. and the causative agent is plum pox virus (PPV). PPV is widespread and poses a serious problem in stone fruit crops in Turkey. A unique strain of PPV has so far been identified in Turkey and called as PPV-Turkey (PPV-T). The aims of the present study were to describe the efficiency of PPV-T transmission via aphids and to identify the susceptibility of differentPrunusrootstocks against PPV-T strain under natural inoculum in Kayseri province located Central Anatolia Region of Turkey. This experiment was established in a small residential orchard where PPV-T infected apricot and plum trees were detected. Five differentPrunusrootstocks from which 200 individuals were planted in PPV-T infected orchard and experiment was designed in a randomized complete block desing with 10 replications per block. All rootstocks were regularly tested by DAS-ELISA and RT-PCR during 2015–2017. The results showed that the most susceptible rootstocks in terms of PPV-T infection were Nemaguard, Myrobalan 29B and Myrobalan 29C with the infection rate of 3.61%, 2.74% and 1.04%, respectively. On the other hand, GF677 and Garnem were never found infected with PPV-T.Aphis gossypii,A. craccivora,A. spiraecola,Brachycaudus helichrysi,Hyalopterus pruni,Myzus persicae,Macrosiphum euphorbiaewere detected as most abundant aphid species in experimental plot. In 2015, the highest percentage of viruliferous aphids was found asA. gossypii(100%), followed byB. helichrysi(77.8%),A. spiraecola(55.72%),M. persicae(46.05%) andH. pruni(30.76%) whereas it was 100% forA. gossypiiandM. euphorbiaefollowed byA. spiraecola(76.32%),M. persicae(73.1%),H. pruni(62.06%) andB. helichrysi(61.53%) in 2016 by squash real time RT-PCR. The present study showed that PPV-T was effectively transmitted by different aphid species in natural conditions in Kayseri district. It was concluded that Nemaguard and Myrobalan which were found to be the most sensitive rootstocks to PPV-T should not be preferred by growers asPrunusrootstock where PPV poses a high risk.

Amaç: Bu çalışmada Elma Çoklu Sürgün Fitoplazma Hastalığı (EÇSF) (Candidatus Pyhtoplasma mali)’nın biyolojik mücadelesinde endofitik fungusların etkinliğinin belirlenmesi amaçlanmıştır. Böylece pratikte kimyasal mücadele olanağı olmayan hastalık etmenine karşı farklı kontrol stratejileri geliştirilebilme olanağının sağlanması hedeflenmiştir. Yöntem ve Bulgular: EÇSF ve endofit fungus izolasyonları için toplam 50 farklı bahçe gezilerek fitoplazma testleri için 360 ağaçtan, endofit funguslar için ise hem sağlıklı hem de fitoplazma ile enfekteli 198 ağaçtan bitki örneği toplanmıştır. Fitoplazma açısından testlenen 360 örnekten 29 tanesi ‘Ca. P. mali’ ile enfekteli bulunmuştur. ‘Ca. P. mali’ ile enfekteli ve sağlıklı elma ağaçlarından endofit fungus türleri izole edilmiş, bu fungusların morfolojik ve moleküler tanısı ile birlikte patojenisite çalışmaları yapılmıştır. Sağlıklı elma ağaçlarından en yaygın olarak izole edilen endofit funguslardan Epicoccum nigrum, Aureobasidium pullulans, Ulocladium consortiale’nin EÇSF hastalığına karşı etkinlikleri incelenmiştir. Her bir fungus izolatının EÇSF hastalık yoğunluğunu farklı düzeylerde etkilediği, en yüksek etkinin A. pullulans’a ait olduğu ve EÇSF hastalık yoğunluğunu uygulama sonrası %34,18 etki değeri ile azalttığı belirlenmiştir. Genel Yorum: EÇSF hastalığının etkili bir kimyasal mücadelesinin bulunmaması ve etmenin karantina listesinde yer alması nedeniyle olası biyolojik mücadele uygulamaları oldukça önemlidir. EÇSF ile enfekteli ağaçlara inokule edilen 3 farklı endofit fungus türünden Aureobasidium pullulans’ın fitoplazma yoğunluğunu diğer 2 etmene göre daha fazla azaltmasından dolayı A. pullulans hastalıkla mücadelede kullanılabilecek biyolojik mücadele ajanı olabilir. Çalışmanın Önemi ve Etkisi: Bu çalışma ile biyolojik mücadele ajanı olan endofit fungusların elmalarda EÇSF hastalığı üzerine etkileri Türkiye’de ilk kez araştırılmış ve hastalığın kontrol stratejilerinin oluşturulmasında önemli ön bulgular elde edilmiştir., Aims: Purpose of this study was to determine the efficacy of endophytic fungi in biological control of Apple Proliferation (AP) Phytoplasma Disease (Candidatus Pyhtoplasma mali). Thus, it was aimed to provide the opportunity to develop different control strategies against the disease agent, which is practically not possible to control chemically.Methods and Results: A total of 50 different orchards were visited to search for the presence of AP and fungal endophyte isolates. For phytoplasma disease 360 samples and for fungal endophytes 198 samples were collected from healthy and symptomatic trees. Of the 360 apple samples which were tested against phytoplasma, 29 were found to be infected with ‘Ca. P. mali’. Endophyte fungi species were isolated from healthy and ‘Ca. P. mali’ infected apple trees. Morphological and molecular diagnosis and also pathogenicity studies were carried out with the isolated fungi. The efficacy of Epicoccum nigrum, Aureobasidium pullulans and Ulocladium consortiale, which were the most commonly isolated endophyte fungi from healthy apple trees, were investigated against AP disease. It was determined that each fungus isolate affected the AP disease intensity at different levels, the highest effect belonged to A. pullulans, and it decreased the AP disease intensity with an effect value of 34.18% after the application.Conclusions: Possible biological control applications are very important because there is no chemical control of AP disease which is on the quarantine list. Aureobasidium pullulans was found to reduce the phytoplasma density more than the other 2 different endophyte fungus species inoculated on trees infected with AP. Therefore, A. pullulans could be a biological control agent which can be used in the AP disease control.Significance and Impact of the Study: In this study, the effects of endophyte fungi, which are biological control agents, on AP disease in apples were investigated for the first time in Turkey and important preliminary findings were obtained in the development of disease control strategies.

Son yıllarda yeni nesil sekans analiz tekniklerinin yaygın olarak kullanılması bağlarda ve diğer bitki türlerinde etiyolojisi bilinmeyen birçok virüs hastalığının etmeninin belirlenmesini sağlamıştır.. Bağlarda bu teknoloji ile saptanan yeni virüslerden en önemlileri Grapevine Pinot Gris Virus (GPGV), Grapevine Syrah Virus-1 (GSyV-1), Grapevine Red-blotch associated Virus (GRBaV) ve Grapevine Roditis Leaf Discoloration Virus (GRLDaV)‘dür. Bu çalışmanın amacı Tekirdağ ve Hatay ili bağ alanlarında GPGV, GSyV-1, GRBaV ve GRLDaV varlığının PCR ve DNA dizileme yöntemleriyle saptanması ve karakterizasyonlarının yapılmasıdır. Bu çalışma kapsamında virüs benzeri simptom gösteren omcaların yanı sıra simptomsuz omcalardan da örnekler alınmış ve toplam olarak Tekirdağ ilinden 191, Hatay ilinden ise 111 örnek toplanmıştır. Tekirdağ ilinden toplanan bağ örneklerinde %43,62 oranında GPGV, %1,04 oranında GSyV1 saptanmıştır. Hatay ilinden toplanan örneklerde ise sadece %0,9 oranında GSyV1 saptanmış ve testlenen örnekler GPGV, GRBaV, GRLDaV açısından temiz bulunmuştur. Tekirdağ örneklerinin GPGV için yapılan RT-PCR analizlerinde kısmi kılıf protein, hareketlilik, ve replikaz genlerini çoğaltan primerler kullanıldığında sırasıyla 411 bp, 302 bp ve 618 bp büyüklüğünde PCR ürünleri elde edilmiştir Bu ürünlerin doğrudan iki yönlü sekans analizi sonucunda ve her üç gen bölgesinin de nükleotid dizilimlerinin gen bankasında kayıtlı farklı GPGV izolatları ile yüksek oranda homoloji gösterdiği saptanmıştır.

Amaç: Bu çalışmada, Adıyaman ili genelinde yetişen badem ağaçlarında apple mosaic virus (ApMV), prunus necrotic ring spot virus (PNRSV), prune dwarf virus (PDV), plum pox virus (PPV) ve apple chlorotic leaf spot virus (ACLSV)’lerinin Double Antibody Sandwich-Enzyme Linked Immuno Sorbent Assay (DAS-ELISA) ve Reverse Transcription-Polymerase Chain Reaction (RT-PCR) yöntemleriyle belirlenmesi, elde edilen virüs izolatlarının filogenetik ilişkilerinin ortaya konulması amaçlanmıştır.Yöntemler ve Bulgular: Adıyaman ilinde yetişen badem ağaçlarından simptomlu ve simptomsuz bitki örnekleri toplanmıştır. Toplanan tüm örnekler DAS-ELISA ve RT-PCR yöntemleri ile testlenmiştir. DAS-ELISA ve RT-PCR analizi sonucunda 34 örneğin yalnız PDV ile enfekteli olduğu saptanmış, ancak testlenen örneklerde diğer virüsler bulunmamıştır. RT-PCR ile elde edilen PDV izolatları doğrudan sekanslanmıştır. Nükleotid sekansları birbiriyle ve GenBank'ta depolanan diğer PDV izolatları ile karşılaştırılarak filogenetik olarak analiz edilmiştir. Adıyaman PDV badem izolatlarının filogenetik ağaçta yüksek homolojiyle aynı grupta yer aldığı, GenBank’a kayıtlı diğer PDV izolatlarından ise farklı bir grupta kümelendiği belirlenmiştir. Bu çalışma Adıyaman ili badem ağaçlarında PDV’nin saptanması konusundaki ilk çalışmadır. PDV badem izolatlarından 15 tanesi MW357407-MW357421 erişim numaraları ile GenBankası’na kaydedilmiştir.Genel Yorum: Adıyaman'da yetişen badem ağaçlarında prune dwarf virus (PDV)’unun varlığı, hem DAS-ELISA hem de RT-PCR testleri sonucunda ilk kez bu çalışma ile kanıtlanmıştır. Adıyaman'da yetişen badem ağaçlarının %30,90 oranında PDV ile bulaşık olması, bölgede badem plantasyonlarının kurulması sırasında önlem alınması gerektiğini göstermektedir. Test edilen badem örneklerinde ACLSV, ApMV, PNRSV ve PPV tespit edilmediğinden, ileride yapılacak çalışmalar ile daha geniş alanları tarayarak örnek sayısının artırılması ve virüslere özgü farklı primer çiftleri kullanılarak yeni testlerin yapılması gerekmektedir. Çalışmanın Önemi ve Etkisi: Adıyaman ilinde yetişen badem ağaçlarında önemli Prunus virüslerinin tespiti ve karakterizasyonu ilk kez yapılmıştır., Aims: In this study, it was aimed to investigate the presence of apple mosaic virus (ApMV), prunus necrotic ring spot virus (PNRSV), prune dwarf virus (PDV), plum pox virus (PPV) and apple chlorotic leaf spot virus (ACLSV) in almond trees in Adıyaman province by Double Antibody Sandwich-Enzyme Linked Immuno Sorbent Assay (DAS-ELISA) and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) methods, to analyse the phylogenetic relationships of obtained virus isolates.Methods and Results: Symptomatic and asymptomatic plant samples were collected from almond trees from Adıyaman province. All samples were tested by DAS-ELISA and RT-PCR methods. As a result of DAS-ELISA and RT-PCR analysis, 34 samples were found to be infected only with PDV and other viruses tested were not detected in the samples. PDV isolates obtained by RT-PCR were directly sequenced and then nucleotide sequences were phylogenetically analyzed with each other and compared with other PDV isolates, deposited in GenBank. Adıyaman-PDV isolates were clustered in a same group with a high homology and differed from other PDV isolates retrieved from the GenBank. This is the first report of the presence of PDV in almond plantations in Adıyaman province. 15 of the PDV almond isolates were registered in GenBank with the accession numbers MW357407-MW357421.Conclusions: The presence of prune dwarf virus (PDV) in almond trees in Adıyaman has been proven for the first time by this study as a result of both DAS-ELISA and RT-PCR tests. The fact that the almond trees in Adıyaman are infected with PDV with an infection rate of 30.90% which makes it necessary to take measures during the establishment of the almond plantations in the region. Since ACLSV, ApMV, PNRSV and PPV are not detected in the tested almond samples, so in future studies, it is recommended to increase the number of samples by surveying larger areas to make new tests using different virus specific primer pairs.Significance and Impact of the Study: Detection and characterization of important prunus viruses on almonds in Adıyaman province has been investigated for the first time.

Cestrum species are being used as hedge and ornamental plants in Turkey. In this study, a Cestrum elegans plant showing chlorotic spots, rings and reddening was subjected to high throughput sequencing of small RNAs, in order to clarify its etiology. Results suggested the presence of tomato chlorosis virus (ToCV), which was further confirmed by RT-PCR using two specific primers amplifying RNA-dependent RNA polymerase (RdRp) and coat protein (CP) of the virus. When 25 Cestrum samples were tested using CP primers, one symptomatic C. elegans and four symptomless C. nocturnum were infected by ToCV. The obtained sequences shared 83–99.9% nucleotide identity with ToCV isolates available in the GenBank. Phylogenetic relationship among Turkish tomato isolates of ToCV and those available in the GenBank showed that two Cestrum spp. isolates of ToCV were closely related to Turkish tomato isolates, while the other three clustered with isolates from different countries.

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Pomegranate is an important crop in the Mediterranean Basin that can be affected by a range of pathogens. With the aim to better understand the impact of viral diseases on pomegranate, two leaf samples from Turkey showing virus-like symptoms such as chlorotic spots and oak-leaf patterns were subjected to high throughput sequencing (HTS). Data analysis indicated the presence of passiflora edulis symptomless virus (PeSV: genus Roymovirus, Potyviridae family) in these two pomegranate samples, consistent with the observation by electron microscopy of flexuous filamentous viral particles 760 to 780 nm long. Further analysis of HTS reads revealed the presence of five PeSV variants in one of the samples and another single variant in the other. PeSV occurrence was also identified from publicly available SRA pomegranate RNA-Seq transcriptomic data from India and China. The genome of these PeSV-pomegranate variants share 78.0&ndash, 86.8% nucleotide identity with that of the reference isolate from passionfruit (MH379332). The presence of PeSV in pomegranate was confirmed by specific RT-PCR assays targeting either the coat protein (CP) or Nla-Pro genes in 37 cultivated and one ornamental pomegranate out of 133 samples collected from the Eastern Mediterranean region of Turkey. To our knowledge, this is the first application of HTS to assess virus occurrence in pomegranate and the first recognition of pomegranate as a new host for PeSV.

Fruit tree diseases caused by phytoplasma have great economic effects on fruit production, especially in Europe. A major phytoplasma is ‘Candidatus Phytoplasma mali’, which causes apple proliferation (AP) disease mainly in cultured and wild forms of apple trees (Seemuller et al., 2011a); however, there has been a report of different hosts, including Prunus avium (L.) L., P. armeniaca L., and P.domestica L. (Mehle et al., 2007). ‘Ca. Phytoplasma pyri’ causes pear decline (PD) disease that is found mainly in cultured and wild forms of pear (Pyrus spp.) and quince (Cydonia oblonga Mill.) (Seemuller et al., 2011b). These phytoplasma are taxonomically classified into the 16SrX group (or AP-group) of phytoplasmas and constitute closely related subgroups (Seemuller and Schneider, 2004). Phytoplasmas are mainly spread by vegetative propagation or the grafting of infected plant material and phloem feeding insects, primarily leafhoppers, planthoppers and psyllids (Weintraub and Beanland, 2006). Only one genus of this last one, Cacopsylla spp., transmit AP-group phytoplasmas to pome and stone fruit trees. In apple orchards, ‘Ca. P. mali’ can be transmitted by two psyllid species. Cacopsylla (Thamnopsylla) picta (Foerster, 1848) (syn. C. costalis) has been reported main vector in Germany (Jarausch et al., 2003, 2011) and northern Italy (Frisinghelli et al., 2000; Carraro et al., 2008), while Cacopsylla (Thamnopsylla) melanoneura (Foerster, 1848) was identified as main vector in Aosta Valley (Tedeschi et al., 2002). C. picta is monophagous on Malus spp. and until now this species have been described only in Europe (Burckhardt, 1994; Ossiannilsson, 1992; Ouvrard, 2014) and Turkey (Klimaszewski and Lodos, 1977, 1979; Drohojowska and Burckhardt, 2014). C. melanoneura has a Palaearctic distribution and is oligophagous on Rosaceae, its principal host plant being a common shrub, hawthorn (Crataegus monogyna L.) (Ouvrard, 2014). In most of studied cases, both psyllid species are present in apple orchards (Jarausch et al., 2003; Delic et al., 2005; Carraro et al., 2008; Mattedi et al., 2008). Two others species living on hawthorn, Cacopsylla peregrina (Foerster, 1848) and Cacopsylla (Thamnopsylla) affinis (Low, 1880), were found able to harbor the phytoplasmas of the AP-group, in particular ‘Ca. P. mali’ (Tedeschi et al., 2009). Their transmission ability was not proven but this result highlights the potential role as vector of these psyllid species. In pear orchards, until recently, two psyllid species were known as vector of ‘Ca. P. pyri’. Cacopsylla (Hepatopsylla) pyricola (Foerster, 1848) has been reported for Great Britain (Davies et al., 1992) and North America (Jensen et al., 1964), while Cacopsylla (Hepatopsylla) pyri (Linne, 1758) was described as the vector in France (Lemoine 1984), Italy (Carraro et al., 1998a) and Spain (Garcia-Chapa et al., 2005). C. pyri is widespread in Europe, in the Caucasus, Georgia, the Middle Asia, including Turkey (Klimaszewski and Lodos, 1979; Burckhardt and Pak. J. Agri. Sci., Vol. 53(2), 383-392; 2016 ISSN (Print) 0552-9034, ISSN (Online) 2076-0906 DOI: 10.21162/PAKJAS/16.3804 http://www.pakjas.com.pk

2nd International Symposium on Plum Pox Virus -- SEP 03-06, 2013 -- Olomouc, CZECH REPUBLIC, WOS: 000358036400017, Turkey is the most important producer and exporter country of apricot, Prunus armeniaca. Production of apricots for fresh market relies on foreign cultivars grown on Mediterranean and Aegean regions while Malatya is the most important region for production of dry apricots based on local cultivars. Plum pox virus (PPV) in Turkey has been known since 1968, but it was not widespread until recent years. Malatya region has been free of sharka disease so far, but the disease has already been reported from many different provinces since 2006. Because of that, introgression of resistance to PPV in the local cultivars with good pomological characteristics became an important objective for the apricot crop. In the current breeding program, obtaining new cultivars resistant to PPV, selection of resistant seedlings by using molecular markers linked to PPV resistance was aimed at. Nineteen local apricot genitors and progenies obtained from the crosses between the PPV resistant cultivar 'Stark Early Orange' (SEO), 'Harcot' and local cultivars such as 'Hacihaliloglu', 'Kabaasi', 'Hasanbey', 'Cologlu', 'Adilcevaz5', 'Sekerpare', 'MahmudunErigi', 'Soganci' and 'Cataloglu' were screened with markers. The markers PGS1.21 and PGS2.23 co-segregating with resistance to PPV were used to screen a total of 189 apricot progenies. None of the local genitors had alleles linked to PPV resistance. Among the progenies screened, 15 seedlings from 'Sekerpare' by SEO, 12 from 'Adilcevaz5' by SEO, 7 from 'Hacihaliloglu' by SEO, 9 from 'Kabaasi' by SEO, 5 from 'Cologlu' by SEO, 9 from 'Cataloglu' by SEO, 4 from 'Hasanbey' by SEO, and 1 from 'MahmudunErigi' by SEO and none of the 'Harcot' by 'Soganci' presented resistant alleles and were selected for further studies., Int Soc Horticultural Sci

Although Plum pox virus (PPV) was first detected in Turkey 44 years ago, the virus is present in a rather limited number of trees. Our recent studies on PPV incidence showed that PPV was introduced rapidly in PPV-free regions and that there are no data available about the role of aphid species and Prunus rootstocks on these new infections. In this study the epide- miological aspect of PPV was studied in Antakya-Hatay, located in the Eastern Mediterranean region of Turkey where PPV was first detected in 2011. The susceptibility of different Prunus rootstocks to PPV was evaluated in an established experimental plot next to a PPV-infected nectarine orchard. Aphid populations were monitored in 2011 and 2012 from the last week of April to the middle of June by the sticky-plant method in both the experimental plot (EP) and the surrounding infected nectarine orchard (SNO). Regularly collected plant samples and aphids were individually tested by DASI-ELISA and squash real-time RT-PCR, respectively. The highest aphid population densities were observed at the end of May in both years. The most abundant aphid species were Aphis gossypii and A. spiraecola both in EP and SNO in both years. The percentage of PPV-viruliferous Myzus persicae, A. fabae, A. gosypii, A. spiraecola, Hyalopterus pruni, Macrosiphon euphorbiae and A. craccivora as estimated by squash real- time RT-PCR were 39.47%, 25.00%, 24.56%, 22.60%, 22.22%, 20.00% and 8.00%, respec- tively. The percentages of viruliferous aphids collected from SNO were 12.5% in A. spiraecola, 12.42% in A. gossypii and 11.11% in H. pruni. At the end of 2012, three Myrobolan 29C and two Adesoto 101 rootstocks were found infected by PPV. Molecular characterization studies showed that PPV-M was the strain present in both the originally infected nectarine plot and the Myrobolan 29C rootstocks.

During inspections in July 2016, ten sets of three stem cuttings were collected from different parts of apple trees ( Malus domestica ) cv. Red Delicious showing dappling, crinkling and irregular yellow spots on their fruits. The samples …

Fig mosaic disease (FMD) and the fig mite, Aceria ficus, are widespread in different fig growing provinces of Turkey. Fig trees (Ficus carica) cv. Bursa siyahı (D1) and an unknown seedling (D2) that showed typical FMD symptoms and was heavily infested by fig mites were used as donor plants for attempted mite transmissions to healthy fig seedlings. Transmission electron microscopy observations of donor plant samples prior to the transmission tests were performed and showed the presence of double membrane bodies (DMBs) in the palisade mesophyll cells. Electron microscopy of all experimentally inoculated fig seedlings showed the same bodies. This result reinforced the suggestion that an agent that elicits the production of DMBs in infected cells is involved in the etiology of FMD. Double-stranded (ds)RNA analyses were also performed from experimentally inoculated plants, and dsRNAs with sizes approximately 1.30 and 1.96 kb were obtained. Reverse transcription–polymerase chain reaction (RT-PCR) products of 468 and 298 bp specific to Fig mosaic virus (FMV) were amplified from both donor and experimentally inoculated plants. BLAST analyses of nucleotide sequences of these fragments showed 90% identity with FMV for the donor plant and 94 to 96% for experimentally inoculated plants. According to these results, FMV is present in both donor and experimentally inoculated plants in Turkey, and this virus is transmissible by A. ficus from fig plant to fig plant.

Leaves from 58 fig tree accessions showing different severity of mosaic and necrotic symptoms were collected in 2 different regions of Turkey and analysed by transmission electron microscope (TEM) and RT-PCR to determine putative causal agents of fig mosaic disease (FMD). Ultrastructural studies showed that double membrane-bound bodies (DMBs) were mainly observed in the parenchyma and mesophyll cells of infected leaves of the cultivars Göklop and Morgüz and some seedlings showing only mosaic symptoms. These bodies were surrounded by a fibrillar matrix in most of the infected cells. Long, flexuous rod-shaped virus-like particles (LFPs) were also observed in vascular tissues of the Bursa Siyahı, Sarılop, Sarızeybek, and Yediveren cultivars, as well as seedlings that exhibited mosaic and necrotic symptoms together. Isometric virus-like particles (IVLPs) were mainly observed in mesophyll parenchyma cells of cv. Yeşilgüz, which showed very mild mosaic symptoms. Some phytoplasma-like bodies, as well as mosaic symptoms, were also observed in the phloem tissues of cv. Morgüz, Göklop, and Yediveren. These kinds of particles were not observed in the healthy plant leaves. RT-PCR analyses revealed that a PCR product of 3.0 kbp was obtained from virus-purified RNA of cvs. Bursa Siyahı, and Sarılop and an unknown cultivar (seedling) using degenerate fig-associated primers. When primers specific for FMD agent in Spain were used, a DNA fragment of 750 bp was amplified from cvs. Göklop and Yeşilgüz. However, no product was obtained by using DC-random primers., Türkiye’nin iki farklı bölgesinden toplanan ve farklı şiddetlerde mozaik ve nekrotik simptomlar gösteren 58 incir ağacından toplanan yapraklar, incir mozaik hastalığının olası etmenlerini saptamak amacıyla transmision elektron mikroskop çalışmaları ve RT-PCR yöntemi ile analiz edilmiştir. Ultrayapısal çalışmalar sonucu sadece mozaik simptomu gösteren Göklop, Morgüz çeşitleri ile bazı çöğürlerin infekteli yapraklarının parankima ve mezofil hücrelerinde çift membranla çevrelenmiş yapılar gözlenmiştir. İnfekteli hücrelerin çoğunda bu yapılar fibrilar matriks ile çevrelenmiştir. Bursa Siyahı, Sarılop, Sarızeybek, Yediveren çeşitleri ile bazı çöğürlerin iletim demetlerinde gözlenen uzun, kıvrımlı çubuk şeklindeki virus benzeri partiküller ise mozaik ve nekrotik simptomların birlikte görüldüğü durumlarda gözlenmiştir. Orta derecede mozaik simptomları gösteren Yeşilgüz çeşidinin mezofil parankima hücrelerinde ise izometrik şekilli virus benzeri yapılar saptanmıştır. Mozaik simptomu gösteren Morgüz, Göklop ve Yediveren gibi çeşitlerin floeminde bazı fitoplazma benzeri yapılar gözlenmiştir. Söz konusu bu yapıların sağlıklı bitki yapraklarında bulunmadıkları saptanmıştır. RT-PCR analizlerinde incir mozaik ile ilişkili dejenere primerler kullanıldığında infekteli örneklerden Bursa Siyahı, Sarılop ve çeşidi bilinmeyen çöğürlerden saflaştırılan RNA’larda 3,0 kb PCR ürünü saptanmıştır. İspanya’daki incir mozaik hastalığı etmenlerine karşı üretilen spesifik primerler kullanıldığında ise Göklop ve Yeşilgüz çeşitlerinde yaklaşık 750 bp büyüklüğünde bir DNA fragmenti saptanmış ancak DC-Random primerleri ile hiç bir ürün elde edilememiştir.

Sixteen Plum pox virus (PPV) isolates collected in the Ankara region of Turkey were analyzed using available serological and molecular typing assays. Surprisingly, despite the fact that all isolates except one, which was a mix infection, were typed as belonging to the PPV-M strain in four independent molecular assays, nine of them (60%) reacted with both PPV-M specific and PPV-D specific monoclonal antibodies. Partial 5' and 3' genomic sequence analysis on four isolates demonstrated that irrespective of their reactivity towards the PPV-D specific monoclonal antibody, they were all closely related to a recombinant PPV isolate from Turkey, Ab-Tk. All three isolates for which the relevant genomic sequence was obtained showed the same recombination event as Ab-Tk in the HC-Pro gene, around position 1566 of the genome. Complete genomic sequencing of Ab-Tk did not provide evidence for additional recombination events in its evolutionary history. Taken together, these results indicate that a group of closely related PPV isolates characterized by a unique recombination in the HC-Pro gene is prevalent under field conditions in the Ankara region of Turkey. Similar to the situation with the PPV-Rec strain, we propose that these isolates represent a novel strain of PPV, for which the name PPV-T (Turkey) is proposed. Given that PPV-T isolates cannot be identified by currently available typing techniques, it is possible that their presence has been overlooked in other situations. Further efforts should allow a precise description of their prevalence and of their geographical distribution in Turkey and, possibly, in other countries. (C) 2009 Elsevier B.V. All rights reserved.