Molecular characterization of cereal yellow dwarf virus-RPV in grasses in European part of Turkey

Yellow dwarf viruses (YDVs) are economically destructive viral diseases of cereal crops, which cause the reduction of yield and quality of grains. Cereal yellow dwarf virus-RPV (CYDV-RPV) is one of the most serious virus species of YDVs. These virus diseases cause epidemics in cereal fields in some periods of the year in Turkey depending on potential reservoir natural hosts that play a significant role in epidemiology. This study was conducted to investigate the presence and prevalence of CYDV-RPV in grasses and volunteer cereal host plants including 33 species from Poaceae, Asteraceae, Juncaceae, Geraniaceae, Cyperaceae, and Rubiaceae families in the Trakya region of Turkey. A total of 584 symptomatic grass and volunteer cereal leaf samples exhibiting yellowing, reddening, irregular necrotic patches and dwarfing symptoms were collected from Trakya and tested by ELISA and RT-PCR methods. The screening tests showed that 55 out of 584 grass samples were infected with CYDV-RPV in grasses from the Poaceae family, while none of the other families had no infection. The incidence of CYDV-RPV was detected at a rate of 9.42%. Transmission experiments using the aphid species Rhopalosiphum padi L. showed that CYDV-RPV was transmitted persistently from symptomatic intact grasses such as Avena sterilis, Lolium perenne and Phleum exratum to barley cv. Barbaros seedlings. PCR products of five Turkish RPV grass isolates were sequenced and compared with eleven known CYDV-RPV isolates in the GenBank/EMBL databases. Compared nucleotide and amino acid sequences of CYDV-RPV isolates showed that the identities ranged from 40.38 - 95.86 % to 14.04 - 93.38%, respectively. In this study, 19 grass species from the Poaceae family and two volunteer cereal host plants were determined as natural reservoir hosts of CYDV-RPV in the cereal growing areas of Turkey. © 2020 Authors

Resistance mechanisms against plant viruses on plants

Kültür bitkilerinde verimi ve kaliteyi, üretim materyalinin genetik potansiyeli, çevre kosulları, kültürel faaliyetlerin uygulanmasındaki basarı derecesi, bu bitkilerde görülen zararlılar ve hastalıklar ile yine bu bitkilere karsı yabancı otların rekabeti belirler. Baslıca bitki hastalık etmenlerinden virüslerin ve diger patojenlerin olumsuz etkilerini ortadan kaldırmak için kültür bitkilerinin genotipik, anatomik, morfolojik ve fizyolojik özelliklerinin degistirilerek onların hastalıklara karsı bagısık ve dayanıklı hale getirilmesi önemli bir biyoteknoloji arastırma konusudur. Bitki hastalık yönetiminin en etkili önlemi de hastalıklara karsı bagısık ve dayanıklı çesit kullanmaktır. Bitki ıslahında her geçen yıl önemli bilimsel gelismeler olmakta ve dolayısıyla bilgi birikiminin güncellenmesi geregi ortaya çıkmaktadır. Bu çalısmada, bitkilerde virüs hastalıklarına ve virüs vektörlerinin davranıslarına karsı olusan dayanıklılıgın biyokimyasal, kalıtsal ve genetik degisim mekanizmaları üzerinde yapılan bazı çalısmaların sonuçları özetlenmistir.Actual yield of cultivated crops are determined by genetic potential, enviromental conditions, degree of cultivation success, harmfull effects of pest and diseases and the competition with weeds. In order to get rid of the advers effects of primary plant diseases caused by viruses and other pathogens, breeding immune and resistant cultivars by changing the genotypic structures, anatomical, morphological and physiological features of plants have become popular research subject of biotechnology. To obtain and the usage of immune and resistant cultivars is considered one of the best way of plant disease management. Scientific know how and scientific advances happens every year on plant breeding. So in this review the results of some research works on plant resistance against viruses and virus vectors were collected and the mechanisms of biochemical and genetic changes in plants were summarized

The Complete Nucleotide Sequence of Barley Yellow Dwarf Virus-PAV from Wheat in Turkey

We report the sequence of an assembled genome of Barley yellow dwarf virus-PAV (BYDV-PAV) from Turkey. This 5,672 nucleotide RNA encodes seven known open reading frames and a possible eighth. This genome from wheat is closely related to BYDV-PAVs in Pakistan, Brazil, and Australia, including one sequenced 34 years ago.Scientific and Technological Research Council of Turkey, International Postdoctoral Research Scholarship Program (TUBITAK-BIDEB); Tekirdag Namik Kemal University, The Scientific Research Projects Coordination Unit (NKU-BAP) [NKUBAP.03.GA.21.289]; Iowa State University Plant Sciences Institute; DARPA Insect Allies Program; Iowa Agriculture and Home Economics Experiment Station, Ames, IA - Hatch Act [4308]; State of Iowa fundsThis study was funded by the Scientific and Technological Research Council of Turkey, International Postdoctoral Research Scholarship Program (TUBITAK-BIDEB), and Tekirdag Namik Kemal University, The Scientific Research Projects Coordination Unit (NKU-BAP, Project No: NKUBAP.03.GA.21.289) to H.I., and the Iowa State University Plant Sciences Institute and the DARPA Insect Allies Program funding to W.A.M. This paper of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA, Project No. 4308 was supported in part by Hatch Act and State of Iowa funds

Incidence of virus diseases in maize fields in the Trakya region of Turkey

A survey on maize virus diseases was conducted in the Trakya region of Turkey by examining 32 496 and 46 871 plants in 2004 and 2005, respectively. Rates of symptomatic plants were estimated at 3.7 to 63.6%, depending on locations. Biological and serological test results revealed the presence of barley yellow dwarf virus-PAV (BYDV-PAV), maize dwarf mosaic virus (MDMV), sugarcane mosaic virus (SCMV), and Johnson grass mosaic virus (JGMV). One hundred forty-two samples were collected randomly from 6492 symptomatic plants in 2004. Seventy-two out of the 142 samples were infected with MDMV, two were infected with BYDV-PAV, 19 with MDMV and BYDV-PAV, two with MDMV, BYDV-PAV and SCMV, and only one sample contained the four viruses. In 2005, 100 other leaf samples were collected randomly from 11 739 symptomatic maize plants. Serological tests revealed that 50% of the samples were infected with MDMV and SCMV; however, five showed mixed infections of two or three combinations of tested viruses. Individual MDMV, SCMV, BYDV-PAV and JGMV infections were detected in five, three, two and four samples, respectively. Presence of MDMV was confirmed by Western blot analysis and IC-RT-PCR. SCMV was also detected by IC-RT-PCR. This is the first study reporting the detection of SCMV and JGMV on maize plants in Turkey.Une enquête sur les maladies virales du maïs a été menée dans la région de Trakya en Turquie avec l’examen, en 2004 et 2005, de respectivement 32 496 et 46 871 plantes. Selon l’endroit, le taux de plantes symptomatiques a varié entre 3,7 et 63,6 %. Les résultats de tests biologiques et sérologiques ont révélé la présence de la souche PAV du virus de la jaunisse nanisante de l’orge (BYDV-PAV), du virus de la mosaïque nanisante du maïs (MDMV), du virus de la mosaïque de la canne à sucre (SCMV) et du virus de la mosaïque du sorgho d’Alep (JGMV). En 2004, 142 échantillons foliaires ont été recueillis aléatoirement sur 6492 plantes présentant des symptômes. Soixante-douze des 142 échantillons étaient infectés par le MDMV, deux étaient infectés par le BYDV-PAV, 19 par le MDMV et le BYDV-PAV, deux par le MDMV, le BYDV-PAV et le SCMV, alors qu'un seul contenait les quatre virus. En 2005, 100 nouveaux échantillons foliaires ont été recueillis aléatoirement de 11 739 plants de maïs présentant des symptômes. Des tests sérologiques ont montré que 50 % des échantillons étaient infectés par le MDMV et le SCMV; cependant, cinq échantillons étaient infectés par des combinaisons de deux ou trois des virus testés. Des infections par un seul virus parmi le MDMV, le SCMV, le BYDV-PAV et le JGMV ont été respectivement détectées dans cinq, trois, deux et quatre échantillons. La présence du MDMV a été confirmée par buvardage Western et par immunocapture suivie de transcription inverse et réaction en chaîne de la polymérase (IC-RT-PCR). Le SCMV a aussi été détecté par IC-RT-PCR. La présente étude est la première à signaler, en Turquie, la présence du SCMV et du JGMV dans le maïs

Epidemic of yellow dwarf virus diseases in cereal growing areas and their control

Dünyada olduğu gibi Türkiye'deki tahıl üretim alanlarında da zaman zaman epidemiler oluşturarak verim ve kalite kayıplarına neden olan sarı cücelik virüslerinin (yellow dwarf virus, YDVs) neden olduğu hastalıklar tahılların en önemli hastalıkları arasındadır. 2016 yılı üretim döneminde, Türkiye'nin tahıl üretim potansiyeli yüksek olan illerinde de görüldüğü gibi, Trakya Bölgesi'nin Edirne, Kırklareli ve Tekirdağ illerindeki tahıl üretim alanlarında sarılık ve cüceliğe neden olan bu hastalıkların epidemileri meydana gelmiştir. Tahıl tarlalarında zaman zaman yaygın hale gelen bu virüs hastalıkları başta buğday olmak üzere tüm tahıl türlerinde verim ve kaliteyi düşürerek ekonomik kayıplara neden olmaktadır. YDVs hastalık epidemisinin görüldüğü Edirne ili başta olmak üzere Kırklareli ve Tekirdağ illerindeki tahıl tarlalarında arazi gözlemleri yapılmıştır. Hastalanan bitkilerin sergilediği sarılık, cücelik ve kızarıklık belirtilerinin görüldüğü kışlık buğday, arpa ve yulaf üretim alanlarından 187 adet enfekteli bitki yaprak örneği toplanmıştır. 138 buğday (Triticum aestivum L.), 19 arpa (Hordeum vulgare L.), 10 adet yulaf (Avena sativa L.) yaprak örneği ile birlikte YDVs'nin konukçusu çok yıllık Poaceae yabancı ot türü kamış (Phragmites austrialis (Cav.) Trin ex.Steudel)'tan da 20 adet yaprak örneği toplanmıştır. Enfekteli yaprak örneklerinde, YDVs'den Barley yellow dwarf virus-PAV (BYDV-PAV), Barley yellow dwarf virus-MAV (BYDV-MAV) ve Cereal yellow dwarf virus-RPV (CYDV-RPV) öncelikle double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) testi ile araştırılmıştır. Enfekteli olduklarından şüphelenilen örnekler reverse transcription polymerase chain reaction (RT-PCR) testine tabi tutulmuştur. DAS-ELISA ve RT-PCR testleri sonucu toplam 187 adet örnekten 89 adedinde ve %47.59 oranında BYDV-PAV; 30 örnekte %16.04 oranında CYDV-RPV ve 4 örnekte ise %2.14 oranında BYDV-MAV virüsleri bireysel olarak saptanmıştır. Bunun yanısıra 187 adet örnekten 14 adedinde ve %7.48 oranında ise YDVs (BYDV-PAV, BYDV-MAV ve CYDV-RPV)'nin karışık enfeksiyonları saptanmıştır. 2016 yılında Edirne ilindeki tahıl üretim alanlarında YDVs enfeksiyonu %36.89 ile en yüksek orana sahipken Kırklareli'nde %21.93, Tekirdağ ilinde ise bu oran %14.44 olarak tespit edilmiştir. YDVs ile etkin ve uygulanabilir mücadele yöntemleri, önceki çalışmalarla saptanmıştır. Trakya Bölgesindeki tahıl üreticileri, çiftçiler ve sektörün diğer paydaşları hastalık etmenleri ve mücadelesi ile ilgili olarak sürekli bilgilendirilmektedirYellow dwarf virus (YDVs) diseases are one of the most important diseases which have reduced crop yield and quality in the cereal growing areas by causing epidemics from time to time on all over the world as well as in Turkey. Just as prevailing in some potential cereal producer provinces of Turkey as well as in Edirne, Kırklareli and Tekirdağ provinces of Trakya Region during the year of 2016, yellow dwarf virus epidemic diseases were taken place. Those virus diseases in cereal fields have become widespread especially in wheat fields which have reduced the yield and quality and caused economic losses. Survey studies were conducted and observation on YDVs disease epidemics in cereal fields especially in Edirne, Kırklareli and Tekirdağ provinces. At least 187 plant leaf samples were collected from the symptomatic winter bread wheat, barley and oat plants exhibiting yellowing, dwarfing, reddish symptoms and signs in the cereal growing areas. So, beside 138 bread wheat (Triticum aestivum L.), 19 barley (Hordeum vulgare L.) and 10 oat (Avena sativa L.) leaf samples, 20 samples were obtained from the perennial Poaceae weed host common reed (Phragmites austrialis (Cav.) Trin ex. Steudel). Barley yellow dwarf virus-PAV (BYDVPAV), Barley yellow dwarf virus-MAV (BYDV-MAV) and Cereal yellow dwarf virus-RPV (CYDV-RPV) from YDVs were searched by employing double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) test. Reverse transcription polymerase chain reaction (RT-PCR) test was implemented for suspected leaf samples. As a result of DASELISA and RT-PCR tests, 89 out of 187 leaf samples at the rate of 47.59% were found infected with BYDV-PAV. As 30 samples at the rate of 16.04% had CYDV-RPV and 4 of 187 leaf samples at rate of 2.14% were infected with BYDV-MAV viruses individually. Merely 14 out of 187 leaf samples at the rate of 48% were found infected with these tested YDVs (BYDV-PAV, BYDV-MAV and CYDV-RPV) as mixed infections. During the year of 2016, YDVs infections were determined at the highest level of incidence rate being 36.89% in the cereal growing areas of Edirne province. As in Kırklareli, YDVs incidence rate was 21.93% and in Tekirdağ province, incidence rate of YDVs was determined as 14.44%. Effective and appropriate control measures against YDVs infections were determined with previous researches. So cereal producers, farmers and the other beneficiaries of food production sector in the Trakya Region have been informed steadily

Trakya bölgesinde üretimi yapılan bazı tahıl türlerinde verim kayıplarına neden olan viral kökenli enfeksiyonların etmenlerinin tanılanması

Türkiyeʼde Trakya Bölgesiʼnde, basta kislik bugday (Triticum aestivum L.) olmak üzere tahil üretimi en yogun bitkisel üretim faaliyetidir. Bölgeʼde tahil üretiminin monokültür seklinde artis göstermesi son yillarda bu kültür bitkilerinde önemli hastaliklarin ortaya çikmasina neden olmustur. 1999 yilindan itibaren bölgede görülmeye baslayan rozetlesme, sarilik, cücelik ve verim düsüsleri ile tanimlanan sistemik virüs belirtileri, Edirne, Kirklareli ve Tekirdag Illeriʼnde tahil ürünlerinin verim ve kalitelerinin düsmesine neden olmustur. Bölgeʼdeki bugdaylar (T. aestivum L.)ʼda % 32.33, arpa (Hordeum vulgare L.)ʼda % 26.52, yulaf (Avena sativa L.)ʼda % 8.32, kusyemi (Phalaris canariensis L.)ʼnde % 61.63 oraninda ve Tritikaleʼde ise ortalama % 8.00 oraninda saptanan virüs hastaliklarinin etmen tanilarinin yapilmasi ve bu virüslerin tarla kosullarindaki enfeksiyonlarina karsi yörede üretilen kislik ekmeklik bugday çesitlerinin reaksiyonlarinin belirlenmesi bu arastirmanin baslica amaçlarini olusturmaktadir. Trakya Bölgesiʼni ve bes ayri tahil türünü temsil edecek sekilde belirlenen ve enfeksiyon görülen 54 tarladan karakteristik belirtiler sergileyen bitkilerden alinan 90 yaprak örneginden elde edilen bitki özsulari, sekiz türden olusturulan indikatör test bitki serilerine mekanik olarak inokule edilmistir. Sonuçta 10 örnekteki virüsün en az iki indikatör bitki türüne, 27 örnege ait bitki özsularinin içerdikleri virüsün ise en az bir indikatör bitki türüne tasindigi saptanmistir. Sürvey çalismasi esnasinda toplanan yaprak biti örnekleri Rhopalosiphum padi L. olarak tanilanmis ise de tahil virüslerini bu yaprak biti türü ile tasimak mümkün olmamistir. Alinan toprak örnekleri ile yapilan çalismalarda da gelisen bitkilerde herhangi bir belirti olusmamistir. Bölgeʼdeki tahil virüslerini serolojik olarak belirlemek amaciyla 11 farkli tahil virüsüne karsi hazirlanmis poliklonal antiserumlar kullanilarak Double Antibody Sandwich Enzyme-Linked Immunosorbent Assay (DAS-ELISA) testi uygulanmistir. Sonuçta 90 tahil yaprak örneginden 63 adedinde Barley Yellow Dwarf Virus-PAV (BYDV-PAV), 9 adedinde Wheat Streak Mosaic Virus (WSMV) ve 2 örnekte ise Türkiyeʼde ilk defa bu çalisma ile saptanan Oat Necrotic Mottle Virus (ONMV)ʼun bulundugu kanitlanmistir. DAS-ELISA testleri sonucu WSMVʼnu içeren bugday yaprak örneklerinden hazirlanan Transmission Elektron Mikroskop (TEM) gridlerinde 15x750 nm boyutlarinda egri çubuk formunda virüs partiküllerinin bulundugu gözlenmistir. Serolojik testlerle BYDV içerdigi saptanan 9 bugday ve 2 arpa yaprak örneklerinden yapilan RNA ekstraksiyonu sonucu, BYDV-PAV virüsüne ait primerler kullanilarak Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) testi uygulanmistir. Sonuçta örneklerin Rhopalosiphum padi L. (Hom:Aphididae) ile tasinan BYDV-PAV virüsüne esdeger 534 Kbʼlik amplifikasyon ürünlerine sahip olduklari ve örneklerin BYDV-PAV virüsüne esdeger bandlar olusturduklari görülmüstür. Böylece Trakya Bölgesi tahillarinda siddetli enfeksiyonlara neden olan virüsün BYDVPAV izolati oldugu anlasilmistir. 2001 yilinda yapilan tarla denemeleri sonucu, Trakya Bölgesiʼne yayilmis bulunan BYDV-PAV virüsünün dogal enfeksiyonlarina maruz kalan 16 kislik ekmeklik bugday çesitlerinin tamami virüse duyarli olarak bulunmus ve sadece Golia, Nina ve Tina çesitlerinin enfeksiyona karsi tolerans gösterdikleri ve virüsten fazla etkilenmedikleri saptanmistir. 2002 yilinda ise yörede yaygin olarak ekilen 25 kislik ekmeklik bugday çesitlerinin de BYDV-PAV virüsüne duyarli olduklari saptanmis, ancak hastalik oraninin düsük olmasi nedeniyle çesitlerin dayaniklilik ve toleransina iliskin reaksiyonlari belirlenememistir. Sonuç olarak Trakya Bölgesi tahil üretim alanlarinda yaygin olarak görülen enfeksiyonlarin virütik kökenli olduklari ve agirlikli olarak BYDV-PAV virüsü basta olmak üzere WSMV ve ONMV virüslerinden ileri geldigi kanitlanmistir. BYDV-PAV ve WSMV Trakya Bölgesi için ve ONMV Türkiye için ilk kayittir

Detection and partial molecular characterization of Plum pox virus on almond trees in Turkey

Almond (Prunus dulcis) is one of the well known stone fruit species grown for its unripe fruits and delicious seeds in Turkey. In the Trakya region, however, some prevailing virus infections have reduced almond yields and quality. In ten districts of Trakya, 260 leaf samples were collected from affected almond trees in June 2010. DAS-ELISA assays and RT-PCR tests were employed for the identification of viruses. As a result of these detection studies, five of the 260 leaf samples gathered from symptomatic almond trees had Plum pox virus (PPV), 81 of them had Prunus necrotic ringspot virus (PNRSV), and 11 samples contained Prune dwarf virus (PDV). Only four out of 260 samples had a mixture of these viruses. Partial nucleotide sequences of five almond isolates of PPV were determined and compared with 17 other PPV isolates in databases. Computer analysis of obtained and published nucleotide sequences showed identity ranged from 75.72% to 96.87%. Of the five PPV almond isolates obtained, however, there was a close nucleotide identity of 95.82-96.61% to Turkish isolates. Phylogenetic analysis of nucleotides and amino acids showed that five PPV isolates of almond from the Trakya Region of Turkey were clustered in the same subgroup with PPV-T Turkish isolates in GenBank. Therefore we can consider almond isolates of PPV as PPV-T strain, like the two other isolates from apricot trees in Turkey

Identification of Apple mosaic ilarvirus (ApMV) on pome fruits in south eastern Marmara region of Turkey

Güneydogu Marmara Bölgesi’nde yumusak çekirdekli meyve üretimi yapılan Bursa, Kocaeli, Sakarya ve Yalova illeri ile bu 4 ile baglı 11 ilçedeki 170 bahçeden Apple mosaic virus (ApMV)’nu saptamak amacıyla yaprak örnekleri toplanmıstır. 2006 yılında yapılan sürveylerde 164 elma, 103 armut, 104 ayva agacından toplanan 371 yaprak örnegi DAS-ELISA testine tabi tutulmustur. DAS-ELISA testi sonucunda 11 farklı elma çesidinin %15.8, 12 farklı armut çesidinin %24, 7 farklı ayva çesidinin ise %21 oranında ApMV ile enfekteli oldugu saptanmıstır. Virüs ile enfekteli oldugu saptanan en önemli çesidin elmada; Starking delicious ve Golden delicious, armutta Santa maria, Akça ve Deveci, ayvada ise Esme çesidi oldugu belirlenmistir.In order to identify Apple mosaic virus (ApMV) on pome fruits, leaf samples were collected from 170 orchards in the 11 disticts of Bursa, Kocaeli, Sakarya and Yalova provinces in 2006. For this purpose leaf samples were collected from 164 apple, 103 pear and 104 symptomatic quince trees. Totally 371 samples were tested by DASELISA for the diagnosis of ApMV. As a result of ELISA 15.8% apple samples from 11 cultivar, 24.7% pear samples of 12 cultivar and 21% quince samples of 7 cultivars revealed ApMV. Starking delicious, Golden delicious of apple, Santa maria, Akca, Deveci of pear and Esme cultivar of quince were found the most susceptible cultivars for ApMV

Detection Of Virus Diseases in Corn (Zea mays L.) Fields in Bursa Province Of Turkey

Türkiye’de mısır (Zea)mays L.) geleneksel olarak dane mısır olarak Doğu Karadeniz Bölgesi’nde üretilmekte iken son yıllarda farklı amaçlara yönelik olarak birçok ilde bu kültür bitkisinin üretimi artmıştır.. Nitekim Bursa İli’nde dane mısır ve silajlık mısır yanında tatlı mısır, şeker sanayi hammaddesi için üretilmeye başlanmıştır. Mısır üretiminde verimi ve kaliteyi olumsuz yönde etkileyen bazı sistemik hastalıkların Bursa İlinde varlığını araştırmak üzere simptomatik yaprak örnekleri toplanmıştır. 2012 yılında yapılan gözlem ve incelemeler sonucu sistemik hastalık simptomları sergileyen 50 yaprak örneğinde, Barley)yellow)dwarf)virusZPAV (BYDVZPAV), Cereal)yellow)dwarf)virusZ RPV (CYDVZRPV), Maize) dwarf) mosaic) virus (MDMV) ve Sugarcane) mosaic) virus (SCMV) virüslerinin varlığı araştırılmıştır. Double antibody sandwich enzymeZlinked immunosorbent assay (DASZELISA) testi uygulanan 50 bitki örneğinin 15 adedinde % 30 oranında MDMV saptanırken 10 adedinde ise % 20 oranında MDMV+SCMV virüslerinin karışık enfeksiyonları belirlenmiştir. Sonuçta Bursa İli mısır tarlalarında gözlenen simptomatik bitkilerin 25 adedinde % 50 oranında virüs enfeksiyonlarından etkilendikleri görülmüştür.Traditionally corn [Zea mays L.) has been produced as a grain crop in the Eastern Black Sea Region of Turkey. Recently corn production for different purposes is extending to different Provinces. Nevertheless in Bursa Province beside grain corn and silage, sweet corn production has been increased recently. Some systemic infections caused the reduction of yield and quality of corn was observed in Bursa corn fields. As a result of field observations, a total of 50 leaf samples exhibiting systemic symptoms were collected and investigated for the presence of Barley yeliow dwarf virus-?KM (BYDV-PAV), Cereal yellow dwarf virus-RPV (CYDV-RPV), Maize dwarf mosaic virus (MDMV) and Sugarcane mosaic virus (SCMV) in 2012. By employing Double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) test 30 % of leaf samples (15 out of 50) were found infected with MDMV and 20% (10 of the 50) were exhibited mix infections of MDMV and SCMV. As a result of these serological test the incidence rate of these viruses was determined as 50 %.in symptomatic corn plants grown in Bursa/Turkey

Molecular Characterization of Cereal Yellow Dwarf Virus-RPV in Grasses in European Part of Turkey

Yellow dwarf viruses (YDVs) are economically destructive viral diseases of cereal crops, which cause the reduction of yield and quality of grains. Cereal yellow dwarf virus-RPV (CYDV-RPV) is one of the most serious virus species of YDVs. These virus diseases cause epidemics in cereal fields in some periods of the year in Turkey depending on potential reservoir natural hosts that play a significant role in epidemiology. This study was conducted to investigate the presence and prevalence of CYDV-RPV in grasses and volunteer cereal host plants including 33 species from Poaceae, Asteraceae, Juncaceae, Geraniaceae, Cyperaceae, and Rubiaceae families in the Trakya region of Turkey. A total of 584 symptomatic grass and volunteer cereal leaf samples exhibiting yellowing, reddening, irregular necrotic patches and dwarfing symptoms were collected from Trakya and tested by ELISA and RT-PCR methods. The screening tests showed that 55 out of 584 grass samples were infected with CYDV-RPV in grasses from the Poaceae family, while none of the other families had no infection. The incidence of CYDV-RPV was detected at a rate of 9.42%. Transmission experiments using the aphid species Rhopalosiphum padi L. showed that CYDV-RPV was transmitted persistently from symptomatic intact grasses such as Avena sterilis, Lolium perenne and Phleum exratum to barley cv. Barbaros seedlings. PCR products of five Turkish RPV grass isolates were sequenced and compared with eleven known CYDV-RPV isolates in the GenBank⁄ EMBL databases. Compared nucleotide and amino acid sequences of CYDV-RPV isolates showed that the identities ranged from 40.38 − 95.86 % to 14.04 − 93.38%, respectively. In this study, 19 grass species from the Poaceae family and two volunteer cereal host plants were determined as natural reservoir hosts of CYDV-RPV in the cereal growing areas of Turkey