Complete genome sequence of a previously undescribed monopartite begomovirus and betasatellite infecting Malvastrum coromandelianum in Cambodia

A previously undescribed monopartite begomovirus was identified from Malvastrum coromandelianum plants exhibiting yellow vein symptoms characteristic of begomoviruses, in Kampot province, Cambodia. The apparently full-length viral component was cloned and sequenced following enrichment of circular DNA by rolling circle amplification and restriction enzyme digestion. The genome of the virus was 2,737 nucleotides in length (KP188831), and exhibited an organization like that of other monopartite begomoviruses, sharing the highest nt identities of 87.7% with Ageratum yellow vein virus (AM940137). A satellite molecule was amplified from total DNA by PCR amplification with the betasatellite-specific primer pair β01/β02. The satellite molecule (1,346 nt, KP188832) had a structure characteristic like other betasatellites associated with begomoviruses, and shared the highest nt identity of 84.8% with Malvastrum yellow vein betasatellite (MN205547). According to the criteria established for species demarcation for classification of begomoviruses ( Geminiviridae ) and betasatellites ( Tolecusatellitidae ), respectively, the virus isolate from M. coromandelianum in Cambodia is a previously undescribed novel monopartite begomovirus species，for which the name Malvastrum yellow vein Cambodia virus (MaYVCV) is proposed, whereas, the betasatellite is identified as an previously undescribed novel betasatellite species, for which the name Malvastrum yellow vein Cambodia batesatellite (MaYVKHB) is proposed.

Viral Diseases of Crops in Nepal

Viral diseases are the important diseases next to the fungal and bacterial in Nepal. The increase in incidence and severity of viral diseases and emergence of new viral diseases causes the significant yield losses of different crops in Nepal. But the research and studies on plant viral diseases are limited. Most of the studies were focused in viral diseases of rice (Rice tungro virus and Rice dwarf virus), tomato (Yellow leaf curl virus) and potato (PVX and PVY). Maize leaf fleck virus and mosaic caused by Maize mosaic virus were recorded as minor disease of maize. Citrus Tristeza Virus is an important virus of citrus fruit in Nepal while Papaya ringspot potyvirus, Ageratum yellow vein virus (AYVV), Tomato leaf curlJava betasatellite and Sida yellow vein Chinaalphasatellite were recorded from the papaya fruit. The Cucumber mosaic virus (CMV) and Zucchini yellow mosaic potyvirus (ZYMV) are the viral diseases of cucurbitaceous crop reported in Nepal. Mungbean yellow mosaic India virus (MYMIV) found to infect the many crops Limabean, Kidney bean, blackgram and Mungbean. Bean common mosaic necrosis virus in sweet bean, Pea leaf distortion virus (PLDV), Cowpea aphid‐borne mosaic potyvirus (CABMV), Peanut bud necrosis virus (PBNV) in groundnut, Cucumber mosaic virus (CMV). Chili veinal mottle potyvirus (CVMV) and Tomatoyellow leaf curl gemini virus (TYLCV) were only reported and no any further works have been carried out. The 3 virus diseases Soyabean mosaic (SMV), Soybean yellow mosaic virus and Bud blight tobacco ring spot virus (TRSV) were found in soybean.Int. J. Appl. Sci. Biotechnol. Vol 6(2): 75-80

Identifikasi Begomovirus yang Berasosiasi dengan Penyakit Kuning pada Mentimun di Jawa Barat dan Bali

<p>ABSTRACT<br />A survey conducted from several cucumber cultivation area of West Java and Bali found some plants showing yellow mosaic, vein banding, and stunting symptoms, caused by Begomovirus infection. This study aimed to detect and determine incidence of Begomovirus on cucumber plants, and analyze variation of Begomovirus coat protein gene in West Java dan Bali. Leaf samples from 50 plants were taken randomly from each location in Sumedang, Karawang, Sukabumi (West Java) and Tabanan, Gianyar, Klungkung (Bali). Disease incidence was determined based on serological assay using specific antiserum of Tomato leaf curl New Delhi virus (ToLCNDV) dan Squash leaf curl virus (SLCV). Incidence of ToLCNDV and SLCV were 28-100% and 30-80%, respectively. PCR using Begomovirus degenerate primers successfully amplified coat protein gene about ± 550bp. There were three Begomovirus species associated with yellowing disease on cucumber plant i.e Squash leaf curl China virus (SLCCNV), ToLCNDV, and Ageratum yellow vein virus (AYVV). Based on nucleotide sequences analysis, it was found that isolate SLCCNV had highest nucleotide homology with SLCCNV isolate Malaysia (EF197940) about 94.5%, and was considered as a strain “China”, whereas ToLCNDV has highest nucleotide similarity with ToLCNDV isolate Indonesia (AB613825) about 99.4% and was considered as a strain “Indonesia”. The AYVV sequences showed highest nucleotide AYVV isolate Nicotiana benthamiana from Indonesia (AB100305) about 92.1%.</p><p>Keywords: Cucumis sativus, Dot immunobinding assay, Squash leaf curl China virus, Tomato leaf curl New Delhi virus</p><p>ABSTRAK<br />Survei yang dilakukan di beberapa pertanaman mentimun di Jawa Barat dan Bali menemukan gejala mosaik kuning, daun keriting, penebalan tulang daun, dan kerdil akibat infeksi Begomovirus. Penelitian ini bertujuan untuk mendeteksi dan menghitung insidensi penyakit yang disebabkan oleh Begomovirus pada tanaman mentimun, serta menganalisis keragaman gen protein selubung Begomovirus di Jawa Barat dan Bali. Sampel daun diambil secara acak sebanyak 50 tanaman dari tiap lokasi pertanaman mentimun di Sumedang, Karawang, dan Sukabumi (Jawa Barat), Tabanan, Gianyar, dan Klungkung (Bali). Deteksi Begomovirus dan insidensi penyakit ditentukan dengan uji serologi DIBA menggunakan antiserum Tomato leaf curl New Delhi virus (ToLCNDV) dan Squash leaf curl virus (SLCV). Insidensi ToLCNDV dan SLCV berturut-turut berkisar 28-80% dan 30-80%. Deteksi dengan teknik PCR menggunakan primer universal Begomovirus berhasil mengamplifikasi gen protein selubung berukuran ± 550 pb. Hasil perunutan nukleotida menunjukkan terdapat tiga spesies Begomovirus yang menginfeksi tanaman mentimun di Jawa Barat dan Bali, yaitu Squash leaf curl China virus (SLCCNV), ToLCNDV, dan Ageratum yellow vein virus (AYVV). Isolat SLCCNV Bali memiliki kesamaan nukleotida dan asam amino terhadap isolat SLCCNV dari negara lainnya berkisar antara 89.8-94.5% dan 94.2-96.3%, dan dikelompokkan ke dalam strain “Cina”. ToLCNDV isolat Jawa Barat dan Bali memiliki kesamaan nukleotida dan asam amino berkisar antara 92.8-99.4% dan 97.3-99.4% dengan isolat ToLCNDV dari negara lainnya, tergolong ke dalam strain “Indonesia”. Gen protein selubung AYVV Bali memiliki kesamaan nukleotida dan asam amino berkisar antara 89.5-92.1% dan 94.7-95.2%, dengan kesamaan tertinggi dengan isolat AYVV asal Indonesia yang menginfeksi Nicotiana benthamiana.</p><p>Kata kunci: Cucumis sativus, Dot immunobinding assay, Squash leaf curl China virus, Tomato leaf curl New Delhi virus.</p>