Çukurova Bölgesi Turunçgil Üretim Alanlarında Citrus Yellow Vein Clearing Virus (CYVCV; Potexvirus citriflavivenae)’ünün Araştırılması ve İzolatlar Arası Benzerlik Oranlarının Belirlenmesi

Prevalence of Citrus Yellow Vein Clearing Virus (CYVCV) Disease and Similarity Rates Among Isolates in Citrus Production Areas of the Eastern Mediterranean Region ABSTRACT: Citrus yellow vein clearing disease was found for the first time in the world in Pakistan, followed by India. This disease was first identified as a new citrus viral disease in Turkey in the 2000s. During this time, eradication efforts were carried out in Adana, the province where the disease was originally discovered, with infected trees cut down. In 2012, it was determined that the causative agent of this disease was Citrus yellow vein-clearing virus (CYVCV) and it was defined as having a single-stranded positive RNA structure. This study aimed to determine CYVCV prevalence in the Çukurova Region, identify new infected locations, and analyze molecular variations between isolates. The survey studies were conducted at between 2016 and 2024, including the provinces of Hatay, Adana, and Mersin. The study focused on lemon and included grapefruit, orange, and sour orange species and variants. CYVCV was investigated using the RT-PCR method in 150 citrus parcels and 10 different seedling production locations, as well as 100 different samples. Samples were collected based on the symptoms of yellow vein clearing and leaf deformation caused by the agent on the leaves. CTAB buffer was used to extract total nucleic acids from the samples. The sequence analysis of the amplicons obtained from RT-PCR analyses was conducted and the resulting base sequences were compared with the registered CYVCVs chosen using the BLAST method in the NCBI database. A total of 35 samples were revealed infected with CYVCV. As a result of the study, it was determined that there was a high similarity between the isolates (97.1-99.8%). Key Words: CYVCV, Turkiye, Citrus, RT-PCRCitrus yellow vein clearing virus (CYVCV; Potexvirus citriflavivenae) was first detected in Pakistan and then in India. In Türkiye, this disease was reported as a new citrus viral disease in the 2000s. In Adana province, where the virus was first detected, eradication was carried out and infected trees were cut down. In 2012, the single-stranded positive RNA structure of CYVCV was identified. The purpose of this investigation was to assess the current state of CYVCV in the Çukurova Region, ascertain the agent's current infection status, and identify molecular differences between the isolates. The survey studies were conducted between 2016 and 2022, including the provinces of Hatay, Adana, and Mersin. The study focused on lemon and included grapefruit, orange, and sour orange species. CYVCV was investigated using the RT-PCR method in 150 citrus parcels and 10 different seedling production locations, as well as 100 different samples. Samples were collected by taking into account the characteristic leaf symptoms of the agent. CTAB buffer was used to extract total nucleic acids from the samples. The sequence analysis of the amplicons obtained from RT-PCR analyses was conducted and the resulting base sequences were compared with the registered CYVCVs chosen using the BLAST method in the NCBI database. A total of 35 samples were revealed infected with CYVCV. These samples that were found to be contaminated underwent an eradication procedure. As a result of the study, it was determined that there was a high similarity between the isolates (97-99.8%).

Citrus yellow vein clearing virus (CYVCV; Potexvirus citriflavivenae) dünyada ilk kez Pakistan’da ardından Hindistan’da tespit edilmiştir. Türkiye’de ise 2000’li yıllarda bu hastalığın varlığı yeni bir turunçgil viral etmeni olarak bildirilmiştir. Bu dönemde virüsün ilk belirlendiği il olan Adana ilinde eradikasyon işlemi gerçekleştirilerek enfekteli ağaçlar kesilmiştir. CYVCV’nin tek sarmal pozitif RNA yapısında olduğu 2012 yılında ortaya konmuştur. CYVCV'nin Çukurova Bölgesi’ndeki durumunu araştırmak, etmenin enfeksiyon durumunu belirlemek ve izolatlar arasındaki farklılığı moleküler olarak saptamak amacıyla bu çalışma yürütülmüştür. Sörvey çalışmaları 2016-2022 yılları arasında Hatay, Adana ve Mersin illerini kapsayacak şekilde güdümlü sörvey çalışması olarak gerçekleştirilmiştir. Çalışma başta limon olmak üzere portakal, greyfurt ve turunç çeşitlerini kapsamıştır. Toplamda 150 turunçgil bahçesi ve 10 farklı fidan üretim alanında CYVCV’nin varlığına bakılmış ve 100 örnek RT-PCR yöntemiyle testlenmiştir. Örneklerin toplanması etmenin karakteristik yaprak simptomları göz önüne alınarak yapılmıştır. Alınan örneklerden TNA ekstraksiyonu CTAB tampon kullanılarak gerçekleştirilmiştir. RT-PCR çalışmaları sonucunda elde edilen amplifikonlar sekans analizine gönderilmiş, elde edilen baz dizilimleri NCBI veri tabanında BLAST metoduyla seçilen kayıtlı CYVCV izolatları ile karşılaştırılmıştır. Toplamda 35 örneğin CYVCV ile enfekteli olduğu belirlenmiştir. Enfekteli olarak belirlenen bu örneklere eradikasyon işlemi uygulanmıştır. Çalışma sonucunda izolatların benzerlik oranlarının yüksek olduğu (%97-99.8) tespit edilmiştir.