Molecular Identification Of Twovirus Species Infecting Pepper And Eggplant In Xinjiang

Pepper (Capsicum annuum) is an important economic crops in Xinjiang. Plant viraldiseases are constantly emerging and have serious detrimental consequences for pepperproduction. In order to ascertain the virus species of pepper showing stem necrotic symptomin Shihezi. Infected pepper plants were subjected to PCR-based diagnosis of Fabavirusinfection. Using universal primers of Fabavirus, fragments of about400bp were amplifiedfrom all samples and one isolate XJP1-1was chosen to clone and sequence. The sequenceswas determined to be389nucleotides and shared95.8%～99.2%nucleotide sequenceidentities with5，-NCR of RNA1of Bean broad wilt virus2(BBWV2). It was concluded thatpeppers plants showing stem necrotic symptom were infected by BBWV2. Based on thedetermined sequence and accessed genomes RNA1of BBWV2in GenBank,5primer pairs inconserved region were designed to further amplify the genome RNA1sequence of XJ14-1.The results showed that complete RNA1was comprised of5958nucleotides (KC790225) andhad95.8%～99.2%sequence identities with RNA1of other BBWV2isolates. Based on theaccessed genomes RNA2of BBWV2in GenBank,4primer pairs were designed to amplifythe genome RNA2sequence of XJ14-1. complete RNA2was comprised of3616nucleotides(HQ283390) and shared79.3%～88.0%sequence identities with RNA2of other BBWV2isolates. Sequence analyses showed that5，-NCR sequence of RNA1and RNA2shared73.8%nucleotide sequence identities and contained the same repetitive sequences(AAACAGCUUUC) and similar location.Eggplant (Solanum melongena) is not easily infected by virus and is considered to be anonhost palnt of Tomato yellow leaf curl virus (TYLCV). In2011, eggplants showing leaf curlsymptoms occurred in greenhouse in Southern Xinjiang. In order to identify the virus species,virus isolate KSQ1-3from eggplant plant showing leaf curl symptom was detected by PCRwith universal primers PA/PB of begomoviruses. The result showed that fragment of about500bp was amplified. The sequence was determined to be518nucleotides and shared highnucleotide sequence identities with DNA-A of Tomato yellow leaf curl virus (TYLCV). Basedon the determined sequence, two primer pairs were designed to amplify the entire DNA of theisolate KSQ1-3. The complete DNA sequence of KSQ1-3consisted of2781nucleotides(KC428753) and had a genomic organization typical for begomoviruses. It shared highsequence identity with isolates of TYLCV (98.5%～99.6%), indicating that KSQ1-3is a isolate of Tomato yellow leaf curl virus. This is the first report of the TYLCV can infecteggplant and eggplant is natural host of TYLCV.