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Penyakit busuk bulir padi yang disebabkan oleh Bulkholderia glumae merupakan penyakit penting yang dapat ditularkan melalui benih padi. Berbagai teknik pengendalian penyakit busuk bulir padi telah dikembangkan untuk mencegah kehilangan hasil panen, salah satunya menggunakan asap cair. Asap cair banyak dikaji sebagai agens pengendalian berbagai penyakit tanaman. Penelitian ini bertujuan menentukan potensi asap cair untuk pengendalian penyakit busuk bulir padi yang disebabkan oleh B. glumae dan sebagai pemacu pertumbuhan bibit padi. Tahapan penelitian terdiri atas: uji potensi asap cair terhadap B. glumae, uji fitotoksisitas asap cair dan pengaruhnya terhadap pertumbuhan benih padi, serta uji keefektifan asap cair dalam menekan B. glumae pada benih terinfeksi. Hasil penelitian menunjukkan bahwa asap cair dengan konsentrasi 2% dapat menekan perkembangan B. glumae secara in-vitro dan tidak menyebabkan fitotoksisitas pada benih padi dengan indeks vigor 90% dan daya berkecambah 90% dibandingkan dengan kontrol dengan nilai indeks vigor dan daya berkecambah sebesar 76% dan 83%. Asap cair dengan konsentrasi 2% juga dapat menekan keparahan penyakit pada fase pembibitan dengan tingkat hambatan relatif 43.8%. Adapun nilai panjang plumula bibit padi pada perlakuan asap cair 2% ialah sebesar 5.87 cm. Nilai plumula tersebut lebih besar dibandingkan dengan kontrol yang hanya sebesar 5.22 cm. Berbeda dengan plumula, nilai panjang radikula tidak mengalami peningkatan signifikan dibandingkan dengan kontrol.

Tomato chlorosis crinivirus (ToCV) diketahui berasosiasi dengan penyakit kuning pada tanaman tomat. Infeksi Crinivirus menunjukkan peningkatan di beberapa daerah di Jawa Barat saat ini. Tersedianya varietas tomat tahan akan menjadi cara efektif dalam pengelolaan penyakit virus, namun perlu upaya mencari sumber ketahanan tanaman terhadap infeksi virus. Penelitian bertujuan menentukan tingkat ketahanan 12 galur tomat terhadap infeksi ToCV. Tomat uji berumur 14 hari setelah pindah tanam diinokulasi dengan ToCV menggunakan 10 ekor kutukebul (Trialeurodes vaporariorum) viruliferus per tanaman. Pengamatan dilakukan terhadap peubah penyakit (periode inkubasi, insidensi dan keparahan penyakit, titer virus) dan peubah agronomi (tinggi tanaman, jumlah daun, jumlah dan bobot buah). Rata-rata periode inkubasi berkisar 9.4–13.5 hari, dan insidensi penyakit berkisar 90.9–100%. Gejala visual bervariasi dari klorosis ringan sampai sedang dan daun menggulung ke atas dengan skor keparahan penyakit berkisar 1.0–3.0. Titer virus diukur berdasarkan nilai absorbansi ELISA, yaitu berkisar 0.358–1.122. Secara umum, infeksi ToCV menghambat pertumbuhan tanaman dan menurunkan jumlah daun, menghambat bobot dan jumlah buah berturut-turut sebesar 6.0–37.8%, 8.6–39.5%, 2.7–33.7% dan 7.0–25.5%. Berdasarkan peubah penyakit, respons galur tomat dapat dikategorikan rentan (BISILB#1029A, BISILB#22, dan BISILB#724B), moderat tahan (BISILB#825B, BISILB#60D, BISIKC#402, BISIKC#96D, dan BISILB#40I), dan tahan (BISILB#1372ORA, BISILB#703A, BISILB#703B, dan BISILB#724A). Namun, sifat ketahanan galur tomat tersebut tidak berkorelasi dengan kemampuan produksi tanaman. Oleh karena itu, perlu dilakukan perbaikan sifat ketahanan pada empat galur tersebut agar lebih adaptif terhadap faktor lingkungan budi daya sehingga dapat dimanfaatkan sebagai tetua varietas tomat unggul tahan ToCV.

Infeksi Papaya ringspot virus (PRSV) di Indonesia pertama kali dilaporkan pada pepaya di Nangroe Aceh Darussalam pada tahun 2012. Sejak itu, PRSV atau penyakit bercak bercincin pada pepaya menyebar ke beberapa daerah di Jawa, Sumatera, Bali, dan Nusa Tenggara Barat. Penelitian ini dilakukan untuk mengonfirmasi keberadaan PRSV di beberapa daerah penanaman pepaya di Jawa dan mengetahui identitas molekulernya. Metode double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) dengan antiserum spesifik PRSV digunakan untuk mendeteksi sampel dari lapangan. Insidensi PRSV hasil deteksi DAS-ELISA di Bogor, Purworejo, Kebumen, dan Bantul berturut-turut sebesar 59.1%, 51.4%, 84.2%, dan 96.2%. Identifikasi lebih lanjut dilakukan dengan reverse transcription-polymerase chain reaction menggunakan primer spesifik (PRSV326/PRSV800), dilanjutkan dengan sikuensing DNA. Fragmen DNA berukuran 475 pb berhasil diamplifikasi dari sampel lapangan dan analisis nukleotida menunjukkan bahwa semua sampel terkonfirmasi PRSV dengan homologi antarisolat berkisar antara 95.4% sampai 99.4%. Analisis filogenetika menunjukkan bahwa isolat-isolat PRSV di Jawa berada dalam satu grup yang sama dengan isolat PRSV-P pepaya dari Thailand.

Squash mosaic virus (SqMV) has been reported to infect cucumber plants in Java and cause a decrease in fruit quality and quantity. Until now, there is no information regarding Sqmv infection in Cucurbitaceae in Bali. In a preliminary research conducted during 2020, we found mosaic symptoms in Gianyar, Bali. SqMV was inferred to be the possible cause of the virus-disease-like symptoms. The study aimed to determine the precence of SqMV in Gianyar, Bali and to obtain information related to its molecular character. This research method includes surveys, field observations, virus identification by RT-PCR, and DNA analysis. Severe disease incidence caused by SqMV was observed on cucumber cultivation in Gianyar that was in the range of 5.81–66.87%. PCR using specific primer for coat protein (CP) gene of SqMV was successfully amplified the DNA fragments of ± 582 bp on samples from Payangan, Tegallalang, Ubud, Sukawati, Blahbatuh, and Gianyar districts, except for samples from Tampaksiring. This indicates that the presence of SqMV is widespread in Java and Gianyar.The SqMV isolate from Bali had the highest nucleotide homology at 91.9–93.4% and amino acids 94.0–94.5 and was closely related to the Brazil isolate (KT923125) and had lower isolate homology than other countries (China, Trinidad, Spain, Japan, Arizona, Cekoslowakia, and Australia). It proved that those mosaic symptoms on cucumber is associated with SqMV infection. SqMV is classified as a quarantine organism of category A2, so it is necessary to prevent its spread to other areas.

Mentimun adalah sayuran penting yang dibudidayakan secara luas di Indonesia. Baru-baru ini mentimun dilaporkan sebagai inang alami Tobacco mosaic virus (TMV), sehingga data respons mentimun terhadap infeksi TMV belum diketahui. P enelitian bertujuan menguji respons sepuluh kultivar komersial mentimun terhadap infeksi TMV. Penularan TMV melalui inokulasi mekanis dan respons mentimun terhadap infeksi TMV diukur berdasarkan peubah penyakit dan agronomi. Hasil penelitian menunjukkan waktu inkubasi berkisar dari 6.9˗12.4 hari setelah inokulasi (HSI) dengan insidensi penyakit berkisar 30-100% tergantung kultivar. Tanaman yang terinfeksi TMV menunjukkan gejala bervariasi dari mosaik ringan hingga berat. Skor keparahan berkisar dari 1.8˗3.0 dengan indeks keparahan penyakit berkisar 0.1-33.3 dan titer virus berkisar dari 0.266˗0.646. Secara umum, i nfeksi TMV kurang menghambat pertumbuhan tinggi tanaman, namun mengurangi jumlah daun pada kultivar Yupiter dan jumlah bunga pada kultivar Alicia F1, Baby 007 F1, Yupiter secara signifikan. Berdasarkan parameter yang diamati, kultivar Vanesa F1 dan Kancil dikategorikan sebagai kultivar tahan, kultivar Naya F1, Panda, Wulan F1, dan Yupiter dikategorikan toleran, serta kultivar Alicia F1, Baby 007 F1, Maestro, dan Monza F1 dikategorikan rentan terhadap infeksi TMV. Kultivar Vanesa F1 dan Kancil tahan dapat dimanfaatkan sebagai tetua untuk perakitan kultivar tahan TMV.

Utilization of plant extracts to suppress Squash Mosaic Virus Infection on ridged gourd (Luffa acutangula [L]. Roxb). Control effort strategies against plant pathogens are necessary to be explored and evaluated its effectiveness intensively. One environmentally friendly control method is biological control by using plant extracts. It is well known that cucurbits arecultivated widely in Indonesia. However, cucurbits are susceptible plants against various pathogens, including viruses. Recently, Squash mosaic virus (SqMV) found to infect cucurbits such as ridged gourd in West Java. The research aimed to explore and evaluate the effectiveness of plant extracts to suppress SqMV infection on the ridged gourd. Three selected plants, namely Bougainvillea spectabilis, Mirabilis jalapa, and Celosia cristata, were tested in greenhouse trial with aspirin as a comparison. The extract was sprayed on the leaves a day before mechanical virus infection. The disease assessments and agronomic parameters were observed. The plant extract treatment showed able to prolonged the incubation period, caused milder symptoms, reduced the virus titer, and showed better plant growth in compared with aspirin treatment or untreated control. B. spectabilis and M. jalapa crude leaf extract revealed able to suppress the SqMV infection with comparable effectiveness with relative inhibition level of disease severity and virus titer up to 48.2% and 80.6 to 81.4%, respectively, indicating their potential as biocontrol for SqMV.

Potato is one of economically important crops in Indonesia. However, its production fluctuates since there are some factors affecting the yield. Recently, we found dwarf disease at potato central production area in Wonosobo and Banjarnegara Regencies in Central Java. So far, there is no information related to the yield loss caused by the dwarf disease on potato. Therefore, the research aimed to estimate the yield loss caused by the dwarf disease on potato in Central Java. The yield loss estimation was determined on some potato cultivations with different disease severities. The disease intensity was observed for five times with interval two weeks on six plots. The quantity and quality of potato yields, and selling price was calculated at the end of the observation and the correlation between the severity of disease and AUDPC (Area under disease progress curve) with yield loss was determined by regression and correlation analysis. The dwarf disease reduced plant height, individual and total tuber weight without affecting the number of tuber yield. The different of disease intensities in some area affected to the percentage of yield loss. The yield loss caused by dwarf diseases on individual potato plants up to 64.42%. Yield loss estimation caused by the dwarf disease in fields with different level of disease intensities ranged from 10.35-26.43%. Regression analysis between disease severities and yield losses showed the R square value at the level of 88.6% and a correlation at the level of 94.14%. These results indicated that the correlation between the severity of dwarf disease and yield loss is high. Keywords: disease severity, potato yield, selling price, tuber quality

Chlorosis and yellowing with green-vein banding on older leaves were observed in surveys of cultivated cucumber fields in 2016 in Java, Indonesia. Initial dot immuno-binding assays detected seven different viruses varying in frequency among over 500 samples from 27 locations. Cucurbit aphid-borne yellows virus (CABYV) was detected at a frequency approaching 100% in four provinces in Java. The coat protein nucleotide and amino acid sequences of four isolates had highest identity with that of CABYV isolate Aileu in East Timor. This is the first report of CABYV infection of cucumber in Indonesia.

Sulawesi Selatan merupakan salah satu sentra produksi kacang tanah di Indonesia. Data infeksi virus pada kacang tanah, prevalensi dan penyebarannya di Sulawesi Selatan masih terbatas. Penelitian bertujuan untuk mendapatkan informasi jenis virus, prevalensi dan sebarannya pada kacang tanah di Sulawesi Selatan. Sebanyak 747 sampel bergejala terinfeksi virus diambil dari delapan kabupaten di Provinsi Sulawesi Selatan. Frekuensi virus ditentukan secara serologi dengan metode Dot Blot Immunobinding Assay (DIBA) menggunakan enam antisera spesifik dan dikonfirmasi dengan Reverse Transcription Polymerase Chain Reaction (RT-PCR). Gejala infeksi virus yang ditemukan bervariasi seperti gejala mosaik, belang (mottle dan stripe), pemucatan tulang daun, klorosis interveinal, serta klorosis dengan penebalan tulang daun disertai malformasi daun. Berdasarkan hasil DIBA menunjukkan bahwa Bean common mosaic virus (BCMV) dan Cucumber mosaic virus (CMV) merupakan virus dengan prevalensi tersebar di semua lokasi dengan frekuensi virus berturut-turut dari Kabupaten Bantaeng, Barru, Bone, Gowa, Maros, Sinjai, Soppeng dan Wajo berkisar 35–100% dan 30-100%. RT-PCR dengan primer spesifik mengonfirmasi keberadaan BCMV dan CMV, serta Polerovirus dari tanaman bergejala klorosis interveinal, dan klorosis dengan penebalan tulang daun disertai malformasi daun. Bean yellow mosaic virus (BYMV), Peanut mottle virus (PeMoV), Peanut stunt virus (PSV) dan Soybean mosaic virus (SMV) terdeteksi positif secara serologi, namun terdeteksi negatif dengan RT-PCR. Terdeteksinya ketiga virus yang menginfeksi tanaman kacang tanah secara alami menjadi temuan baru di Sulawesi Selatan

Gejala tulang daun kuning (vein yellowing) dan malformasi daun yang diduga disebabkan oleh virus ditemukan pada ubi jalar IR Melati di daerah Kendalpayak, Malang, Jawa Timur. Amplifikasi DNA/cDNA menggunakan primer universal Begomovirus, Potyvirus, dan Cucumovirus menunjukkan positif teramplifikasi DNA dengan primer universal Begomovirus, dan Potyvirus, namun negatif dengan primer universal Cucumovirus. Berdasarkan runutan sikuen nukleotida, gejala tulang daun kuning dan malformasi daun disebabkan oleh infeksi ganda Pepper yellow leaf curl virus (PYLCV) dan Sweet potato virus C (SPVC). Analisis identitas DNA dengan perangkat lunak BioEdit menunjukkan homologi paling tinggi sebesar 98.5% terhadap PYLCV isolat cabai dari Bangli Bali, dan sebesar 98% terhadap SPVC dengan isolat ubi jalar asal Jepang dan Amerika Serikat. Laporan ini merupakan temuan baru infeksi alami PYLCV dan SPVC pada ubi jalar di Indonesia.

Cucumber mosaic virus (CMV) merupakan patogen penting pada Cucurbitaceae, diantaranya melon. Pengelolaan virus di lapangan cukup sulit dilakukan. Salah satu upaya untuk menekan infeksi virus yaitu melalui penyehatan tanaman menggunakan bakteri agens hayati. Penelitian ini bertujuan menguji potensi isolat bakteri Bacillus cereus (BC), Chromobacterium haemolyticum (CH), Ralstonia pickettii (RP), dan Pseudomonas flourescen s (PF) dalam menekan infeksi CMV pada tanaman melon. Pengujian pengaruh bakteri terhadap performa kecambah dilakukan melalui perlakuan perendaman benih dalam suspense bakteri di laboratorium. Efikasi bakteri dalam menekan infeksi CMV dilakukan dengan cara perendaman benih dan penyemprotan tanaman dengan suspense bakteri dalam percobaan di rumah kaca. Pengamatan dilakukan terhadap peubah penyakit dan agronomi, dan aktivitas enzim peroksidase. Hasil penelitian menunjukkan perlakuan bakteri BC menunjukkan performa kecambah terbaik di antara perlakuan bakteri lainnya. Perlakuan bakteri tidak berpengaruh terhadap masa inkubasi dan insidensi penyakit , namun secara nyata menurunkan keparahan penyakit dan akumulasi virus dibandingkan kontrol. Aktivitas enzim peroksidase lebih tinggi setelah perlakuan bakteri dan inokulasi CMV dibandingkan perlakuan sebelum inokulasi. Bakteri RP merupakan bakteri terbaik dalam menekan infeksi CMV melalui aktivitas antivirus dan induksi ketahanan dengan peningkatan aktivitas peroksidase.

Tungau hama merupakan salah satu penyebab penurunan produksi pepaya di Pulau Lombok. Penelitian bertujuan menentukan insidensi, sebaran, dan identitas tungau hama pepaya di Pulau Lombok. Sebaran ditentukan berdasarkan insidensi tungau hama pada 50 lokasi pengambilan contoh dan tungau hama diidentifikasi secara morfologi dan molekuler berdasarkan runutan rDNA ITS2. Hasil penelitian menunjukkan terdapat 12 spesies tungau berdasarkan identifikasi morfologi, yaitu Aculops pelekassi, Calacarus carinatus, Brevipalpus californicus, B. obovatus, B. phoenicis, Tenuipalpus pasificus, Eutetranychus africanus, Panonychus citri, Tetranychus fijiensis, T. kanzawai, T. piercei, dan Tarsonemus bilobatus dengan insidensi berkisar antara 2–72%. Di antara spesies yang ditemukan, P. citri merupakan tungau hama dengan sebaran dan insidensi tertinggi (72%). Hasil analisis persebaran menunjukkan bahwa keanekaragaman spesies tungau hama pada tanaman pepaya di Pulau Lombok adalah tinggi dengan tingkat dominansi rendah dan tingkat kemerataan spesies yang tinggi. Uji PCR dan analisis runutan DNA berhasil mendeteksi dan mengidentifikasi enam spesies tungau hama, yaitu T. piercei, T. kanzawai, E. africanus, dan P. citri (Tetranychidae), pada 500–600 pb serta B. californicus dan B. phoenicis (Tenuipalpidae) pada 600–700 pb. Similaritas tertinggi ditemukan pada T. piercei dan T. kanzawai (100%). Ini merupakan laporan pertama keberadaan B. californicus sebagai hama pada tanaman pepaya di Pulau Lombok.KeywordsFrekuensi kemunculan; PCR; Perunutan DNA; SebaranAbstractMites are one obstacle of papaya production in Lombok Island. Thus, the aim of research was to determine incidence, distribution and identity of mites on papaya plant in Lombok Island. Distribution is determined based on incidence of in 50 sampling area, while mites identified morphological and molecularly based on rDNA ITS2. This studies revealed that there were 12 species of mites based on morphological, namely Aculops pelekassi, Calacarus carinatus, Brevipalpus californicus, B. obovatus, B. phoenicis, Tenuipalpus pacificus Eutetranychus africanus, Panonychus citri, Tetranychus fijiensis, T. kanzawai, and T. pierce with an incidence ranging 2-72%. Among species found, P. citri has the highest distribution and incidence of 72%. The results of the distribution analysis showed that diversity of mite species was high, with low dominance and high evenness. PCR assay successfully amplified DNA of six species, namely T. piercei, T. kanzawai, E. africanus, P. citri with the DNA size of 500-600 bp and B. californicus, B. phoenicis with the DNA size of 600-700 bp. The highest similarity species was found on T .piercei and T. kanzawai (100%). This was the first report of B. californicus infestating on papaya in Lombok.

Potato (Solanum tuberosum) is an important vegetable crop in Indonesia. A small survey was conducted for virus diseases in November 2011 in Lembang, West Java, as part of assessing the sanitary status of potatoes produced in farmers' fields. Among the six potato fields surveyed, one field had nearly 20% of plants displaying stunted growth with leaves showing mild chlorotic spots and reduced size of lamina. Tubers harvested from symptomatic plants showed no necrosis symptoms. Symptomatic leaves from three representative potato plants were positive for Potato virus Y (PVY) when tested with PVY-specific immunostrips (Agdia Inc., Elkhart, IN). Leaf samples from virus-positive plants were imprinted on FTA Classic Cards (Whatman International Ltd., Maidstone, UK), air dried, and shipped to Washington State University for confirmatory diagnostic tests. Total nucleic acids were eluted from FTA cards (1) and subjected to reverse transcription (RT)-PCR using primers (PVY/Y4A and PVY/Y3S) specific to the coat protein (CP) of PVY (3). Nucleic acid extracts from samples infected with PVY ordinary strain (PVYO), tuber necrosis strain (PVYNTN), tobacco veinal necrosis strains (PVYEU-N and PVYNA-N), and a recombinant strain (PVYN:O) were included as standards to validate RT-PCR assays. The approximately 480-bp DNA fragment, representing a portion of the CP, amplified in RT-PCR was cloned into pCR2.1 (Invitrogen Corp., Carlsbad, CA). DNA isolated from four independent recombinant clones was sequenced from both orientations. Pairwise comparison of these sequences (GenBank Accession Nos. KF261310 to 13) showed 100% identity among themselves and 93 to 100% identity with corresponding sequences of reference strains of PVY available in GenBank (JQ743609 to 21). To our knowledge, this study represents the first confirmed report of PVY in potato in West Java, Indonesia. Studies are in progress to assess the prevalence of PVY in other potato-growing regions of Indonesia and document the presence of different strains of the virus (2). Since the majority of farmers in Indonesia plant seed selected from their previous potato crop, there is an increased risk of primary and secondary spread of PVY through the informal seed supply system, leading to its increased significance to potato production in Indonesia. Therefore, strengthening foundation seed potato and supply chain programs will promote the production of virus-free potatoes in Indonesia. References: (1) O. J. Alabi et al. Plant Dis. 96:107, 2012. (2) A. Karasev and S. M. Gray. Am. J. Potato Res. 90:7, 2013. (3) R. P. Singh et al. J. Virol. Methods 59:189, 1996.

Anthracnose (Colletotrichum gloeosporioides) is an important disease infecting fleshy fruits. The efficacy of chitosan to suppress C. gloeosporioides infection and its ability to increase the length of fruit storage was evaluated. C. gloeosporioides was isolated and purified from mature papaya. Chitosan was mixed in the potato dextrose agar, and sprayed on the surface of papaya fruit with the concentration of 0.05, 0.1, 0.25, 0.5, 0.75 and 1%. It showed that chitosan concentration of 0.75-1% inhibited C. gloeosporioides growth in vitro up to 72.17-85.21%. Application of chitosan on fruit at concentration of 0.25% suppressed the disease incidence and severity; whereas chitosan concentration of 0.75% was able to suppress the disease incidence, severity, and increase the length of fruit storage twice longer than control.Key words: anthracnose, chitosan, Colletotrichum gloeosporioides, papaya, the length of storage.

Cucumber mosaic virus strain Soybean (CMV-S) merupakan salah satu jenis virus terbawa benih yang menyebabkan penurunan produksi kedelai dan dominan menginfeksi kedelai di Jawa. Penggunaan varietas kedelai unggul tahan merupakan cara terbaik mengendalikan infeksi virus. Namun, varietas kedelai unggul hasil pemuliaan yang ada saat ini umumnya untuk peningkatan produksi dan belum memprioritaskan ketahanan terhadap penyakit virus, sehingga diperlukan pengujian respons ketahanan varietas terhadap CMV-S. Varietas unggul yang diuji ketahanannya dalam percobaan di rumah kaca yaitu Argomulyo, Anjasmoro, Burangrang, Cikuray, Detam 1, Detam 2, Grobogan, Sinabung, dan Wilis. Respons ketahanan terhadap CMV-S diukur berdasarkan parameter penyakit (periode inkubasi, tipe gejala, indeks keparahan penyakit, titer virus) dan parameter pertumbuhan tanaman (tinggi tanaman, jumlah bunga, indeks sensitivitas cekaman). Data percobaan dianalisis secara deskriptif untuk parameter penyakit dan pertumbuhan tanaman. Hasil penelitian menunjukkan bahwa periode inkubasi, ekspresi gejala, keparahan dan titer virus CMV-S bervariasi antarvarietas. Infeksi CMV-S dapat menghambat pertumbuhan tanaman pada semua varietas dan jumlah bunga yang lebih sedikit pada varietas Argomulyo, Anjasmoro, Grobogan, Sinabung, dan Wilis. Varietas Grobogan dikategorikan rentan, varietas Argomulyo, Anjasmoro, Cikuray, Sinabung, dan Wilis termasuk toleran, dan varietas Burangrang, Detam 1, dan Detam 2 termasuk tahan terhadap infeksi CMV-S. Indeks sensitivitas cekaman dari varietas kedelai yang diuji beragam, yang menunjukkan perbedaan genetik antarvarietas dalam merespons infeksi CMV-S. Tiga varietas unggul tahan (Burangrang, Detam 1, dan Detam 2) dapat digunakan sebagai tetua pada perakitan varietas tahan terhadap CMV-S.

White tip disease on rice caused by Aphelenchoides besseyi is categorized as emerging infectious disease in Indonesia because the disease incidence and its geographical distributionare increasing rapidly. Until presently, there is no information related with mass culture technique of A p . besseyi in Indonesia. Thus, studies to obtain pure population of A p . besseyi are necessary to be conducted to support various research aspects in the future. This research is aimed to study A p . besseyi pure mass culture technique by rearing the nematode on three fungal species. Three different fungal cultures on PDA medium, i.e. Alternaria padwickii, Fusarium semitectum, and Botrytis cinerea were tested as A p . besseyi cultivation media. To obtain the optimum condition for nematode cultivation, the fungal cultures were incubated in three different temperature. The nematodes were surface sterilized with 0.1% streptomycin sulfate followed by washing with sterilized water before infesting the nematode into fungal culture. Subsequently, 25 sterilized nematodes were infested into 7 days old of fungal culture and incubated at 20oC, 25oC and 30 oC. After 21 days, nematodes were harvested and counted the final population. Among fungal species tested as rearing medium, the best culture for A p . besseyi reproduction was on Al. padwickii culture at 25 oC with average final population up to 9,115 per petri dish and reproduction factor 364.6. At a 30oC, A p . besseyi was failed to develop its population in all the fungal cultures tested. It indicated that the optimum temperature for reproduction of A p . besseyi on those of fungal species was 20-25 oC.

Bean common mosaic virus (BCMV) merupakan virus penting pada kacang panjang di Indonesia. Salah satu cara untuk mengendalikan BCMV adalah dengan penggunaan kitosan. Pada penelitian sebelumnya, kitosan komersial dengan konsentrasi 0,9% dilaporkan mampu menekan infeksi BCMV yang ditularkan oleh Aphis craccivora dengan mekanisme yang belum diketahui. Penelitian ini bertujuan untuk mengkaji mekanisme kitosan dalam menekan transmisi BCMV yang ditularkan oleh A. craccivora. Kitosan yang diuji yaitu kitosan murni dengan konsentrasi 0,1%–1,1% dan kitosan komersial konsentrasi 0,9% sebagai pembanding. Kitosan diaplikasikan dengan cara penyemprotan daun dengan volume 3 ml/tanaman pada hari sebelum penularan BCMV menggunakan tiga ekor kutudaun yang mengandung virus. Peubah yang diamati, yaitu periode inkubasi, insidensi penyakit, keparahan penyakit, akumulasi virus pada tanaman dan kutudaun, serta deteksi gen CP BCMV, PR1, dan PR3 dengan RT-PCR. Secara umum perlakuan kitosan mampu menekan transmisi BCMV oleh A. craccivora. Periode inkubasi tanaman perlakuan berkisar antara 7–9 hari. Perlakuan kitosan murni menekan insidensi dan keparahan penyakit antara 40%–80% dan 35,71%–78,57% tergantung konsentrasi kitosan. Kitosan komersial menghambat insidensi dan keparahan penyakit sampai 100%. Perlakuan kitosan pada konsentrasi 0,9% baik kitosan murni maupun komersial menunjukkan akumulasi BCMV yang lebih rendah dibandingkan kontrol tanpa perlakuan, yaitu pada kitosan komersial 0,9% memiliki nilai absorbansi ELISA (NAE) sebesar 0,26 ± 0,29 dan pada kitosan murni 0,9% memiliki NAE sebesar 1,15 ± 1,69, sedangkan kontrol tanpa perlakuan memiliki NAE sebesar 3,13 ± 0,17. BCMV positif terdeteksi pada kutudaun menunjukkan bahwa kutudaun tidak makan inokulasi pada tanaman perlakuan. Amplifikasi gen CP BCMV dengan RT-PCR menunjukkan positif teramplifikasi pada semua perlakuan kitosan kecuali perlakuan kitosan komersial. Gen PR1 tidak teramplifikasi, sedangkan gen PR3 teramplifikasi pada semua perlakuan. Akumulasi PR3 tertinggi terdapat pada perlakuan 0,5% dan 0,7% dibandingkan dengan perlakuan lain dan kontrol. Berdasarkan hasil tersebut, perlakuan kitosan lebih berperan sebagai penghambat makan kutudaun daripada sebagai penginduksi ketahanan tanaman.KeywordsBCMV; Kutu daun; Pathogenesis-related protein; PCR; Vigna sinensis L.AbstractBean common mosaic virus (BCMV) is an important virus on beans in Indonesia. One of methods to control BCMV is by chitosan. The previous report showed that commercial chitosan was able to suppress BCMV infection transmitted by Aphis craccivora with an unknown mechanism. This study aimed to examine the mechanism of chitosan in suppressing the transmission of BCMV by A. craccivora. Chitosan used in this research is a pure chitosan with a concentration of 0.1%–1.1% and 0.9% of commercial chitosan as a comparison. Chitosan is applied by spraying the leaves at one day before the transmission of BCMV. BCMV transmitted by using three viruliferous aphids. The incubation period of virus, disease incidence, and severity, virus accumulation in plants and aphids by ELISA were observed, BCMV CP, PR1, and PR3 genes was detected by RT-PCR. In general, chitosan treatments suppressed the transmission of BCMV by A. craccivora. The incubation period ranges from 7–9 days. The pure chitosan treatments suppressed the disease incidence and severity ranged from 40%–80% and 35.71%–78.57%, respectively depends on concentration of chitosan. The commercial chitosan inhibited disease incidence and severity up to 100%. The treated plants at concentration 0.9% either pure or commercial chitosan showed accumulation of BCMV significantly lower in compared with untreated control plants, i.e. 0.9% in commercial chitosan had ELISA absorbance value (NAE) of 0.26 ± 0.29 and pure chitosan 0.9% had NAE of 1.15 ± 1.69 while the untreated control had an NAE of 3.13 ± 0.17. Further, BCMV were detected aphids which feed on treated plants during inoculation feeding period, indicating virus left over on aphids. Amplification of BCMV CP gene by RT-PCR showed positively amplified by all treatments except commercial chitosan treatment. PR1 gene are not amplified, whereas PR3 gene amplified in all the treatments, but the accumulation higher on treated plants at concentration 0.5% and 0.7% in compare with other treatments. Based on those results, chitosan treatment suppress the BCMV transmission by aphids due to the role of chitosan as anti-feedant which hampered aphids transmit the virus during inoculation feeding period rather than as resistance inducer.

Penyakit mosaik pada tanaman nilam disebabkan oleh beberapajenis virus, yaitu Potyvirus, Potexvirus, Cucumber mosaic virus (CMV),dan Broad bean wilt virus 2 (BBWV2). Penelitian ini bertujuan untukmengidentifikasi secara serologi dan molekuler virus-virus yangberasosiasi dengan gejala mosaik pada nilam di KP. Manoko, KP. Cicurugdan lahan petani di Cijeruk. Sampel daun nilam baik yang menunjukkangejala mosaik atau pun tidak diambil dari setiap lokasi penanamanmasing–masing sebanyak 30 sampel. Kejadian penyakit ditentukan melaluideteksi serologi dengan Direct-ELISA dan Indirect-ELISA terhadap sampelmenggunakan empat antiserum, yaitu CMV, Cymbidium mosaic virus(CymMV), Potyvirus, dan BBWV2. Deteksi molekuler dengan RT-PCRdilakukan untuk mengonfirmasi virus baru yang ditemukan. Hasilpenelitian menunjukkan bahwa gejala infeksi virus yang ditemukan padanilam bervariasi, yaitu mosaik lemah, mosaik kuning hijau, mosaik denganpenebalan, mosaik dengan malformasi daun, dan bintik kuning. Secaraserologi, kejadian virus pada setiap kebun bervariasi. Di KP Manoko,Potyvirus dan BBWV2 lebih dominan (100%) dibandingkan CymMV. DiKP Cicurug, kejadian Potyvirus dan CMV terlihat lebih dominan (83,3 dan80%) dibandingkan BBWV2 dan CymMV, sedangkan di Cijeruk, BBWV2lebih dominan (90%) dari Potyvirus (50%) dan CMV (13,3%). Hasil RT-PCR dengan primer degenerate BBWV, diidentifikasi BBWV2 padasampel daun nilam dari Manoko, Cicurug, dan Cijeruk, sedangkan denganprimer general Potexvirus, diidentifikasi CymMV hanya dari sampel daunnilam dari asal Manoko. Hasil penelitian ini merupakan laporan pertamatentang BBWV2 dan CymMV pada tanaman nilam di Jawa Barat yangmengindikasikan bahwa virus merupakan kendala utama pada perbenihannilam yang harus segera diatasi.Kata kunci: BBWV2, CymMV, mosaik, Pogostemon cablin Benth, PCRABSTRACTMosaic symptoms on patchouli plant are associated with severalviruses, i.e. Potyvirus, Potexvirus, CMV, and BBWV2. The objective ofthe study was to detect virus(es) associated with mosaic symptoms onpatchouli at the the patchouli seed nurseries, in Manoko, Cicurug, andCijeruk. Thirty leaf samples either showing typical symptomatic mosaic orasymptomatic were taken from each location. Serological testing byDirect-ELISA and Indirect-ELISA using four antisera namely CMV,Cymbidium mosaic virus (CymMV), Potyvirus, and BBWV2 was carriedout to test the incidence of each virus. Molecular detection by RT-PCR wasperformed to confirm the new virus(es). The results showed that symptomsof virus infection were found vary, i.e. weak mosaic, green yellow mosaic,mosaic with thickening, mosaic with leaf malformations, and yellow spot.Based on the serological detection, virus(es) incidence varied at each seednurseries. In Manoko, Potyvirus, and BBWV2 were more dominant(100%) compared with CymMV. In Cicurug, Potyvirus and CMV weremore dominat (83.3 and 80%) compared with BBWV2 and CymMV.While in Cijeruk, BBWV2 was the most dominant (90%) than Potyvirus(50%) and CMV(13.3%). Result of RT-PCR with degenerate primers pairof BBWV was succesfully identified BBWV2 from Manoko, Cicurug, andCijeruk samples, whereas by using Potexvirus general primary, CymMVwas identified only from Manoko samples. BBWV2 and CymMV werefirst reported to infect patchouli in West Java. The result indicate thatvirus(es) are the major constraint on patchouli seed that should bemanaged immediately.Key words: BBWV2, CymMV, mosaic, Pogostemon cablin Benth, PCR

Tobacco mosaic virus (TMV) is a newly emerging virus on cucumber in Java. Regardless the importance of TMV on Cucurbitaceae, little is known about the existence of TMV in Cucurbitaceae plants. The study aimed to detect and identify TMV on bitter gourd, ridged gourd, and watermelon. Symptomatic leaves were collected from several cucurbit cultivations at 5 regencies in West Java, Central Java and East Java provinces. The frequency of virus on samples were determined serologically by DIBA method using specific antisera to 6 viruses (CMV, CABYV, PRSV, SqMV, TMV, and ZYMV). Nucleic acid detection was conducted by RT-PCR using universal primer for Tobamovirus followed by DNA sequencing to confirm virus identity. The results revealed that samples were infected by 6 viruses with frequency varied and multiple infections occurred. The frequency of TMV infection ranged from 5.9 to 89.6%. RT-PCR successfully amplified DNA fragment with size ± 800 bp from bitter gourd, ridged gourd, and watermelon. The similarity of coat protein gene among isolates reached up to 100%. These TMV isolates showed highest nucleotide and amino acid similarity with cucumber isolate from Brebes regency and other isolates infecting several different crops from other countries. This is a new report on the existence of TMV on different cucurbit species in the fields.

Detection of plant viruses can be done by protein or nucleic acid approaches. The immunocapture-reverse transcription-polymerase chain reaction (IC-RT-PCR) method is a combination of the two approaches. Research was carried out to develop and validate IC-RT- PCR based-detection method for SCSMV, which can be applied for the sugarcane seed indexing program to support the national government’s goal for sugar self-sufficiency. Evaluation of the IC-RT-PCR method was conducted using 5 field samples. Conventional PCR and serological methods, i.e. dot immunobinding assay (DIBA) and enzyme-linked immunosorbent assay (ELISA) was also performed in the same time. All field samples gave a positive reaction to SCSMV antibodies in the DIBA and ELISA methods with the intensity of the reaction varying from low to high. SCSMV was still detected on plant extract up to 104 dilution by ELISA and DIBA. Specific DNA fragments were successfully amplified from 2 field samples using the conventional PCR method; whereas the IC-RT-PCR method was successfully amplified all field samples. Optimization test showed that the IC-RT-PCR method was able to detect SCSMV from plant extract up to 10−10 dilutions. IC-RT-PCR method is more sensitive than conventional PCR and might be recommended for the indexing method to produce high-quality virus-free sugarcane seed.

Conventional PCR is a reliable method for detecting SCSMV. The availability of quantitative PCR (qPCR) can increase the power of PCR as detection method due to its high sensitivity and ability to quantify the template DNA in the reaction mixture. The study was aimed to validate the qPCR method for detection of SCSMV, and to develop detection methods for virus indexing program in seed canes production. qPCR method developed in this study was relative-qPCR with the regression equation of Y = -7,255 * log X + 11.752 for the SCSMV standard curve, so the value of X = 10 (-0.138 * Ct + 1,620). Ct value is inversely proportional to the concentration of cDNA. The greater the Ct value, the lower the concentration of cDNA in the sample. It was proved that qPCR method is more sensitive compared to conventional PCR, because it was able to detect SCSMV in samples not detected by conventional PCR methods. The relation between the Ct value and the incidence and severity of the disease on the field was assessed using field samples for qPCR. It was shown that Ct value and virus concentration did not have relation to the incidence and severity of the disease in the fields.

Erwinia chrysanthemi (currently Dickeya sp.) is one of the A2 quarantine pest that must be concerned of its distribution on potato in Indonesia. The aim of this study is to detect and identify E. chrysanthemi from potato in Java. A total of 400 samples of potato plants showing symptoms of soft rot were obtained from several potato areas in Pangalengan and Garut (West Java), Dieng (Central Java), and Batu-Malang (East Java). Disease incidence was determined by indirect enzyme-linked immunosorbent assay (I-ELISA) using polyclonal antiserum. E.chrysanthemi was isolated from plant samples with positive ELISA results. Furthermore, bacterial isolates were characterized by GEN III OmniLog ID System and PCR using specific primers Ec3F/Ec4R, as well as the universal 16S rRNA primer pair of 27F/1429R. The incidence of E. chrysanthemi based on ELISA was obtained. Based on physiological characters; Gram, catalase, oxidase, and oxidation-fermentation, there were 4 isolates similar to the genus of Erwinia. However, the results of Gen III OmniLog System, PCR, and nucleotide sequences analysis of 16S rRNA confirmed that none of the isolates were identified as E.chrysanthemi. Otherwise, those 4 isolates were identified as Pseudomonas oryzihabitans, Pantoea agglomerans, and Pseudomonas viridiflava. The result of this study indicated that the existence of E. chrysanthemi as an A2 quarantine pest on potato in Java can not be confirmed and remains as an A1 quarantine pest.

Virus infection is an important production constraint for soybean. Research was conducted to detect virus infection from soybean samples collected from several locations in Java. Leave samples from 50 plants was taken randomly from each location in Bogor, Cirebon, Bantul, and Ponorogo. Field symptoms was observed and disease incidence was determined based on serological assay using specific antibodies to Cucumber mosaic virus (CMV), Soybean mosaic virus (SMV), Cowpea mild mottle virus (CPMMV), and Bean pod mottle virus (BPMV). Incidence of CMV, SMV, and CPMMV was 72–84%, 14–24%, and 6–8%, respectively; whereas infection of BPMV was not found. Specific viral DNA of CMV, Potyvirus, and Geminivirus was successfully amplified using specific primer for CMV coat protein, universal primer for Potyvirus and Geminivirus, respectively. Nucleotide sequence analysis showed that isolate CMV from soybean has the highest homology (99%) to CMV strain S, Potyvirus isolates has the highest homology (90%) to BCMV isolate Mungbean from China and BCMV strain Blackeye from Vietnam, and Geminivirus isolates has the highest homology (96%) to Pepper yellow leaf curl virus (PYLCV) from Bogor and Java. Phyllogenetic analysis showed that CMV strain S formed

Recently, a mosaic disease was observed on jack bean cultivation in Dramaga, Bogor,West Java. The symptom on infected plants, i.e. combination of pale and dark green area was more obvious on young leaves. Vein banding, leaf malformation, and growth inhibition was also observed in infected plants. The symptom was not very obvious in older leaves. Serological detection gave positive reaction to Bean common mosaic virus (BCMV) antiserum, but reaction was negative when detected using specific primer to coat protein (CP) of BCMV strain black eye by reverse transcription polymerase chain reaction. DNA fragments were successfully amplified by RT-PCR using universal primer of CP gene and degenerated primer for cylindrical inclusion gen (CI) of Potyvirus. DNA analysis showed the highest homology (86.4–91.5%) to several isolates of BCMV-infecting different crops from several countries based on partial sequence of CP, whereas based on partial sequence of CI the highest homology (87.3%) was to BCMV-RU1-P. This is the first report of BCMV infection on jack bean in Bogor, West Java, Indonesia.

Bean common mosaic virus (BCMV) is one of the most important virus infecting yard long bean because it can decrease yield and seed transmitted. The aims of research were to determine the effect of plant age infected by BCMV on seed transmission efficiency of the virus, as well as its effect on plant growth. BCMV was mechanically inoculated on yard long bean at 1, 2, 3, and 4 weeks after planting (WAP). Observation was conducted for incubation period, disease incidence and severity, seed transmission efficiency of the virus, plant height, and productivity of the plants. Virus infection was detected using indirect ELISA method. The results showed that the earlier infection of BCMV occurred the shortest incubation period, the most severe symptoms, the highest inhibition of plant growth, and productivity. Disease severity was 94.6, 83.8, 81.1, and 69.6% on plants inoculated at 1, 2, 3, and 4 WAP, respectively. Disease incidence and virus titer was not affected by infection on different plant age. Seed transmission of BCMV was 7, 66, 39, and 24% on plants inoculated at 1, 2, 3, and 4 WAP, respectively. Infection on 2 WAP was considered the critical times for BCMV to be seed-borne on yard long bean.

Aphis craccivora merupakan salah satu hama penting pada kacang panjang. Selain menimbulkan kerugian bagi tanaman, A.craccivora juga berperan penting sebagai vektor Bean common mosaic virus (BCMV) di lapangan. Penelitian ini bertujuan untuk menguji efektivitas kitosan terhadap perkembangan populasi dan preferensi makan A. craccivora dan kemampuan A. craccivora dalam menularkan BCMV. Kitosan diaplikasikan dengan cara penyemprotan pada daun pada konsentrasi antara 0,1-1%. Pengujian perkembangan populasi dan preferensi makan kutudaun dilakukan pada tanaman dan daun kacang panjang yang diberi perlakuan kitosan. Tanaman kontrol tidak diberi perlakuan kitosan. Penularan BCMV dilakukan dengan menggunakan tiga imago A. craccivora yang mengandung BCMV per tanaman. Perlakuan kitosan mampu menekan perkembangan populasi dan mengurangi preferensi makan A. craccivora secara nyata dibandingkan dengan kontrol pada semua perlakuan. Selain itu, perlakuan kitosan dapat menekan penularan BCMV melalui A. craccivora yang ditunjukkan oleh kejadian dan titer BCMV yang nyata lebih rendah dibandingkan dengan kontrol. Penekanan populasi dan preferensi makan kutudaun serta infeksi BCMV diduga berhubungan dengan kemampuan kitosan sebagai penghambat makan ( anti-feedant ) A. craccivora. Penekanan infeksi BCMV melalui kutudaun yang ditunjukkan dengan penekanan insidensi, keparahan dan titer BCMV secara nyata dibandingkan dengan kontrol. Di antara konsentrasi kitosan yang diuji, konsentrasi 0,9% merupakan konsentrasi kitosan yang paling efektif dalam menekan A. craccivora dan BCMV.

Gejala infeksi virus banyak ditemukan di pertanaman mentimun di Jawa Barat. Namun, sulit membedakan virus penyebab hanya berdasarkan pengamatan gejala visual. Penelitian ini bertujuan untuk pemutakhiran data virus yang menginfeksi mentimun di Kabupaten Bogor, Karawang dan Subang, Jawa Barat. Sampel tanaman bergejala dikoleksi dari tiap lokasi. Frekuensi virus ditentukan secara serologi dengan metode DIBA ( dot immunobinding assay ) menggunakan antiserum Cucumber mosaic virus (CMV), Cucurbit aphid borne yellow virus (CABYV), Cucurbit green mottle mosaic virus (CGMMV), Papaya ringspot virus (PRSV), Squash mosaic virus (SqMV), Watermelon mosaic virus (WMV), dan Zucchini yellow mosaic virus (ZYMV) . Deteksi asam nukleat dilakukan terhadap virus baru yang dominan dengan reverse transcription polymerase chain reaction (RT-PCR)/PCR . Hasil deteksi menunjukkan bahwa frekuensi virus CMV, CABYV, CGMMV, PRSV, SqMV, WMV, dan ZYMV berturut-turut di B ogor mencapai 98%, 100%, 86%, 0%, 8%, 32%, dan 6% , di Subang mencapai 86%, 100%, 88%, 2%, 8%, 60%, and 46%, dan di Karawang 100%, 100%, 98%, 14%, 72%, 68%, and 64% . CMV, CABYV, and CGMMV were the most common viruses detected in three regencies , while PRSV only detected on samples from Subang and Karawang. RT-PCR /PCR menggunakan primer spesifik atau universal belum berhasil mendeteksi CGMMV dan WMV, namun berhasil mengonfirmasi keberadaan PRSV, Polerovirus, dan Begomo virus . Kata kunci : Cucurbitaceae, Geminiviridae, Luteoviridae, Potyviridae, Tobamovirus

Streak mosaic is a new disease of sugarcane in Indonesia caused by Sugarcane streak mosaic virus (SCSMV). An extensive survey conducted during milling season 2008/2009 at 30 sugar factories (SF) across the Java revealed that about 30 % of observed sugarcane fields of 28 SF were affected by the streak mosaic disease. Most commercial cane cultivars were infected by the virus but the cultivar PS 864 was found most susceptible. RT-PCR detection, using SCSMV coat protein specific gene primers SCSMV-cpF and SCSMV AP3, successfully amplified a 500 bp DNA fragment, suggesting the positive identity of the SCSMV with all the tested symptomatic samples. Protein analysis of the virus confirmed that SCSMV has a coat protein of size approximately 40 kDa and flexuous, filamentous particles about 890 nm in length was observed under an electron microscope. The virus was easily transmitted by infected cane cuttings and mechanically by sap inoculation and cutting knife. Host range test on 23 plant species revealed that maize, sorghum and Dactyloctenium aegyptium were alternative hosts of SCSMV. A preliminary yield loss assessment on PS 864 cultivar revealed that the disease incidence at ≥50 % reduced sugar yield by about 20 %. Hot water treatment of cane cuttings was not able to eliminate the virus in cane stalks but only postponed the appearance of the symptom. Response of 16 commercial cane cultivars to artificially inoculation of SCSMV using an abrasive pad rubbing technique showed that only five cultivars were resistant to the disease.

Turnip mosaic virus (TuMV) is an important seedborne virus that infects vegetable crops, especially Brassicae group, in Indonesia. Reliable detection method having high accuracy is required to detect the virus from seeds in order to avoid disease incidence as early as possible. A study was conducted to evaluate three total RNA extraction methods from Brassica seeds for TuMV detection using reverse transcription- polymerase chain reaction. The samples used are Brassica rappa seeds and seedling germinated for 3, 5, and 7 days. Total RNA extraction methods evaluated consisted of Wylie method, Randles method, and commercial kit as comparation. Total RNA extracted using Wylie and Randles methods has high concentration but low level of purity, on the other hand total RNA obtained using commercial kit has low concentration but high level of purity. Detection of TuMV from seed was successfully carried out using Wylie and Randles methods, TuMV from 3 - day old seedlings was detected using all three methodes, TuMV from 5-day old seedlings was only detected using Randles method, whereas TuMV from 7-day old seedlings was not detected using all three methodes. Total RNA extraction method using Wylie and Randles methodes is recommended for detection of TuMV from caisin seed using RT-PCR technique. Key words: Brassica rappa seed, reverse transcription- polymerase chain reaction, Total RNA, Turnip mosaic potyvirus

Sugarcane streak mosaic virus (SCSMV) is a new emerging virus infecting sugarcane in Indonesia. The virus can be found almost in every sugarcane plantations in Java and it was known as sett-borne virus. Attempt to get virus-free seedling meet difficulties due to lacking an easy, and accurate detection method. SCSMV antiserum is not available yet commercially. Nucleic acid detection by RT-PCR also hampered difficulties in releasing RNA virus from sugarcane tissues. Here we reported the simple direct tube method with minor modification as the convenient way to provide total RNA template from infected sugarcane leaf, stalk and sheath for RT-PCR detection of SCSMV.Key words: RNA extraction, RT-PCR, SCSMV, tube PCR

Recently, field surveys were conducted in several orchid nurseries in Bogor (West Java), Magelang (Central Java) and Malang (East Java). We found that most of the commercially orchids sampled from Bogor was infected by virus-like disease. The symptoms depend on the orchid species. Thus, the symptoms varied such as mottle, mosaic and necrotic flecks either on the leaves or on the flowers. Similiar symptoms were not found in samples obtained from Central Java and East Java. A Tobamo-like virus was inferred to be possible cause of the viral disease-like symptoms. Serological test of the samples by ELISA showed positive against Odontoglosum Ringspot Virus (ORSV) antibody and was negative against Cymbidium Mosaic Virus (CyMV) antibody. Total RNA was extracted from symptomatic plants and RT-PCR was carried out by using a pair of coat protein (CP) gene primer of ORSV. It was successfully amplified a 500 bp of DNA fragment and it was directly sequenced. The nucleotide sequence of CP gene had confirmed the identity of ORSV. Phylogenetic analysis based on the CP nucleotide sequences were grouped into only one major cluster. The ORSV isolate from Bogor (Sd 21) and the other isolates were clustered in the same group and had highest nucleotide homology (99%). These results provide first evidence of ORSV infecting orchids in Bogor, Indonesia.

Severe mosaic with leaf malformation and green vein banding was observed on yam bean in West and Central Java, Indonesia. Virions of the causal virus were flexuous filaments, about 700 nm in length, with a coat protein of 30 kDa. The virus was transmitted by mechanical inoculation and by aphids in a nonpersistent manner. The nucleotide sequence of the coat protein gene had the highest identity with that of Bean common mosaic virus (BCMV, genus Potyvirus) isolate VN/BB2-5. Based on demarcation criteria, including the genome sequence and host range, we tentatively designate this isolate as BCMV-IYbn (Indonesian yam bean).

Viral RNAs are specifically selected for packaging during viral infection. Specific packaging occurs through an interaction between viral RNAs and structural coat proteins (CPs). The specific recognition of viral RNAs by CPs plays a crucial role in diverse facets of the viral life cycle and in the packaging event. The binding of CP to specific RNA elements is required for viral protein translation during infection initiation in alfalfa mosaic virus (28) and for the regulation of translation and the initiation of RNA packaging in the RNA phages (38). In retroviruses, nucleocapsid protein is thought to stimulate genomic RNA dimerization, which is required for efficient RNA packaging, reverse transcription, and recombination (14, 31). Many plant viruses require RNA packaging for systemic spread and for cell-to-cell movement (3, 10). Therefore, the CP-RNA interaction is a critical event in the viral life cycle. Compared with the characterization of trans-acting factors such as CP in RNA packaging, however, the RNA elements involved in specific packaging have not been well characterized for many viruses. One of the best-characterized RNA elements is “origin of assembly” of tobacco mosaic virus (36, 40). cis-acting sequences for RNA packaging have also been demonstrated in several icosahedral viruses, including flock house virus (39), Sindbis virus (37), hepatitis B virus (17), the human immunodeficiency viruses (2, 14, 22), and turnip crinkle virus (32). Brome mosaic virus (BMV) is an icosahedral plant RNA virus and is the type member of the genus Bromovirus in the family Bromoviridae in the alphavirus-like superfamily (18). The genome of BMV consists of three species of messenger sense single-stranded RNA (1). RNA1 (3.2 kb) and RNA2 (2.9 kb), which encode the 1a and 2a replicase proteins, respectively (1, 13, 19), are packaged separately into individual particles (21). RNA3 (2.1 kb), which encodes the 3a cell-to-cell movement protein (35), is packaged into a single particle together with subgenomic RNA4 (0.9 kb) (21). RNA4 is synthesized from the minus strand of RNA3 (25) and encodes CP. CP is required for packaging, cell-to-cell movement, and the systemic spread of the virus (29, 33, 34). A highly conserved N-terminal arginine-rich motif in BMV CP plays an important role in BMV RNA packaging through RNA-CP interactions (4, 5, 33, 34). The crystallographic structure of BMV virions has been determined (23). RNA regions or elements involved in the packaging of BMV RNAs have been assigned to the coding region of BMV RNA1 by UV cross-linking and band-shift assays (11) as well as to the 3′-proximal region of the 3a open reading frame (ORF) in RNA3 (9). The tRNA-like structures (TLS) in the 3′-untranslated regions of BMV RNAs also play a crucial role in BMV RNA packaging in vitro (6). In the present study, we delimit a nucleotide sequence required for the efficient packaging of BMV RNA3 and show that 69 nucleotides (nt) in the 3′-proximal region of the BMV 3a ORF, especially a predicted stem-loop structure (30 nt), is essential for the efficient packaging of BMV RNA3. We also propose the presence of elements in the BMV 3a ORF that are involved in the regulation of the copackaging of RNA3 and RNA4.

Brome mosaic virus (BMV), a tripartite RNA plant virus, accumulates RNA3-derived defective RNAs (D-RNAs) in which 477–500 nucleotides (nt) are deleted in the central region of the 3a protein open reading frame (ORF), after prolonged infection in barley. In the present study, six artificial D-RNAs (AD-RNAs), having deletions of the same size as the naturally occurring D-RNA but at different positions in the 3a ORF, were constructed and tested for their amplification and encapsidation in barley protoplasts by coinoculation with BMV RNA1 and 2, or RNA1, 2, and 3. Northern blot analysis of RNA accumulation in total and virion fractions showed that deletions of 492 nt in the 3′-proximal and the 5′-proximal regions of the 3a ORF decreased encapsidation efficiency of the AD-RNAs compared with that of RNA3, whereas deletions in the central region enhanced encapsidation efficiency. The present results also show that deletion positions affect competition with RNA3 in the amplification and encapsidation of AD-RNAs.

Mosaic disease on Indonesian patchouli associated with infection of TeMV, BBWV2, CymMV and CMV. TeMV, BBWV2 and CymMV has been identified molecularly, while CMV just was detected serologically. The objective of this study was to identify CMV from patchouli by molecular approach based on CP gene nucleotide sequence Leaf samples were collected from three mosaic symptomatic patchouli plants in greenhouse of Balittro. Leaf samples were extracted for the total nucleic acids (RNA + DNA). Nucleic acids were amplified using specific primer for CP gene of CMV by one step RT-PCR technique. The DNA of PCR product with the size of ~ 650 bp was directly sequenced and analyzed for its homology with sequences of CMV isolates extracted from Gene Bank. CMV CP gene from patchouli showed the highest of nucleotide and amino acid sequence similarities, 97,1 and 97,7% respectively, with um Japanese isolates. Phylogenetic tree analysis revealed that CMV from patchouli was closely related with um-Japanese isolate with 100% bootstrap value, and clustered with another CMV isolates in subgroup IB. Since the CMV subgroup I was more virulent than subgroup, it is necessary to increase the awareness of the CMV occurrence in another plant. Key words : homology analysis, phylogeny tree, nucleotides, amino acid Abstrak Penyakit mosaik pada tanaman nilam di Indonesia berasosiasi dengan infeksi Telosma mosaic virus (TeMV), Broad bean wilt virus 2 (BBWV2), Cymbidium mosaic virus (CymMV) dan Cucumber mosaic virus (CMV). TeMV, BBWV2 dan CymMV sudah diidentifikasi secara molekuler, sedangkan CMV baru terdeteksi secara serologi. Karakte risasi molekuler setiap virus diperlukan sebagai salah satu dasar pengambilan tindakan pengendalian. Penelitian ini bertujuan untuk mengidentifikasi CMV asal tanaman nilam secara molekuler berdasarkan sekuen nukleotida gen CP. Tiga sampel daun nilam bergejala terinfeksi virus diambil dari koleksi tanaman nilam di rumah kaca Balittro. Sampel daun diekstraksi asam nukleat totalnya (RNA+DNA). Asam nukleat total diamplifikasi dengan teknik one step reverse transcriptase polymerase chain reaction (RT-CR) menggunakan primer spesifik gen coat protein (CP) CMV. Produk PCR berukuran 650 pb (pasang basa) dirunut sekuen nukleotidanya serta dianalisis homologi dan hubungan filogenetikanya dengan sekuen isolat-isolat CMV yang ada di GenBank. Sekuen nukleotida dan asam amino gen CP CMV asal nilam menunjukkan persentase kemiripan terbesar (97,1 dan 97,7%) dengan isolat um -Jepang. Analisis filogeni menunjukkan bahwa CMV asal nilam berkerabat sangat dekat dengan CMV isolat um-Jepang dengan nilai bootstrap 100%, dan berada dalam satu kelompok dengan isolat-isolat CMV subgrup IB. Keberadaan CMV subgrup IB pada tanaman nilam perlu diwaspadai karena subgrup I lebih virulen dibandingkan subgrup II. Penelitian ini merupakan laporan pertama karakterisasi molekuler CMV nilam, baik di Indonesia maupun di luar negeri, yang dapat digunakan sebagai salah satu dasar pengambilan tindakan pengendalian. Kata kunci: analisis homologi, pohon filogeni, nukleotida, asam amino

Carnation mottle virus (CarMV) merupakan virus penting pada tanaman anyelir di Indonesia maupun di dunia. Deteksi virus yang mudah dan cepat, diperlukan untuk memantau sumber induk anyelir bebas virus. Tujuan penelitian adalah mengevaluasi tiga metode preparasi RNA total yang mudah dan cepat dari tanaman anyelir sebagai templat one step RT-PCR. Sumber RNA total adalah dari daun dan batang anyelir terinfeksi CarMV. Metode yang dievaluasi yaitu SDT, SEM, dan kit komersial sebagai pembanding. Optimasi dilakukan terhadap konsentrasi akhir primer (0.4 – 1.0 µM) dan MgCl 2 (1.5 dan 2.0 mM). Metode SDT dan SEM berhasil mendapat RNA total dari tanaman anyelir baik dari sampel daun maupun batang. Keberhasilan yang didapat dengan metode SDT dan SEM sebanding dengan kit komersial. One step RT-PCR RNA total yang digabungkan dengan metode SDT dan SEM menghasilkan intensitas DNA yang sebanding dengan kit komersial. RNA total dari daun sebagai sumber templat one step RT-PCR terbaik dibandingkan batang. Preparasi RNA total dengan metode SDT dan SEM adalah metode cepat, mudah, dan murah dalam menyediakan templat one step RT-PCR. Konsentrasi primer 0.4 µM dan MgCl 2 2 mM merupakan konsentrasi optimum dan menghasilkan hasil amplifikasi terbaik Keywords Carmovirus; Simple extraction method (SEM); Simple direct tube (SDT); One step RT-PCR Abstrack Carnation mottle virus (CarMV) is an important virus on carnation plants in the world, including in Indonesia. A rapid and easy virus detection is necessary to monitor the source of virus free carnation mother plant. The aim of the research was to evaluate three methods of rapid and easy total RNA preparation from carnation plants as template of one step RT-PCR. The total RNA source is from the CarMV infected leaf and stem of carnations. The evaluated method namely simple direct method (SDT), simple extraction method (SEM), and commercial kit as comparison. Optimization was performed to a final concentration of premiere (0.4 – 1.0 µM) and MgCl2 (1.5 and 2.0 mM). SDT and SEM method successfully obtained a total RNA from both leaves and stems samples. The obtained success by the SDT and SEM methods were comparable with these of commercial kit. One step RT-PCR of total RNA combined with SDT and SEM methods produced DNA intensity comparable with commercial kits. Total RNA from leaves known to be the best source of one step RT-PCR template compared to these from stem. Total RNA preparation by SDT and SEM method is a method of quick, easy, and inexpensive to provide a template one step RT-PCR. Premiere and MgCl2 concentration of 0.4 μM and 2 mM, respectively were optimum concentration and produced best amplification result.

On plants at 59 sugarcane plantations in Central and East Java, Indonesia, we found virus-like symptoms such as streak mosaic. The virus was transmitted mechanically and was sett-borne. The nucleotide sequence of the coat protein gene had the highest identity with that of Sugarcane streak mosaic virus (SCSMV) isolate Pakistani. We tentatively designate this isolate as SCSMV-Idn (Indonesia).

Carnation mottle virus (CarMV) merupakan salah satu virus penting pada tanaman anyelir dan semua kultivar anyelir yang ditanam di Jawa Barat terinfeksi oleh virus ini. Penelitian bertujuan mendapatkan metode eliminasi CarMV yang efektif untuk membebaskan planlet anyelir dari virus. Inisiasi eksplant terinfeksi dilakukan pada media MSO dan perbanyakan planlet dilakukan pada media perbanyakan MS yang mengandung 1,0 ppm BA dan 0,5 ppm kinetin (MSZ). Metode eliminasi CarMV yang diuji terdiri atas perlakuan 2-thiourasil dan amantadin dengan konsentrasi masing-masing 0, 5, 10, 15, 20, 25, dan 30 ppm, dan ribavirin 5 ppm sebagai pembanding. Tunas apikal planlet ditanam pada media perlakuan (MSZA). Setelah tunas tumbuh, meristem terminal diambil 0,5 mm untuk ditanam pada media MSZ. Kultur meristem terminal dari planlet pada perlakuan 2- thiourasil menghasilkan planlet bebas virus sebesar 0 – 57%. Konsentrasi 2-thiourasil 25 ppm menghasilkan persentase planlet bebas virus tertinggi, namun perlakuan tersebut toksik pada tanaman. Perlakuan amantadin menghasilkan 25,0 – 54,55% planlet bebas virus. Di antara perlakuan yang diuji, perlakuan antiviral amantadin dengan konsentrasi 5 – 30 ppm lebih optimal menghasilkan planlet anyelir bebas CarMV dan tidak toksik terhadap tanaman. Perlakuan amantadin 5 – 20 ppm mampu menghambat virus lebih tinggi dibandingkan perlakuan 2-thiourasil pada konsentrasi yang sama. Amantadin 5 – 30 ppm menghasilkan tingkat penghambatan virus sebesar 42,94 – 59,57%, sedangkan 2-thiourasil sebesar -8,18 – 63,03%. Senyawa 2-thiourasil dan amantadin berpotensi sebagai agen antiviral untuk mendapatkan tanaman anyelir bebas CarMV.

Virus tungro disease is a serious problem to rice crop in a certain area of rice production in Indonesia. The disease is caused by a combined infection of Rice Tungro Bacilliform Virus (RTBV) and Rice Tungro Spherical Virus (RTSV). Both viruses were reported to infect ratoon rice plants, weeds, and wild rice. The study was conducted to detect RTBV and RTSV on some weeds. Weed samples were collected from rice fields in West Java, Bali, West Nusa Tenggara, Papua, and West Sumatera. The detection of RTBV and RTSV were carried out using Polymerase Chain Reaction (PCR) and Reverse Transcription (RT) – PCR, employing coat protein gene specific primers. RTBV specific DNA fragment of ~1400 bp size was successfully amplified from various weed species including: F. miliacea, C. iria, M. vaginalis, L. adscendens, S. zeylanica, D. sanguinalis, and E. crusgalli. RTSV specific DNA fragment of ~787 bp size was successfully amplified from weed species of F. miliacea, L. octovalvis, and D. sanguinalis. RTBV or RTSV specific DNA fragment was not amplified from L. flava and P. distichum. Weed samples infected by both viruses did not show any tungro symptom. Virus detection based on molecular technique was able to determine the status of weed whether it is as an alternate host of viruses. Weeds sanitation prior to rice planting, therefore, should be considered as an integral part of virus disease management.

Gejala infeksi virus ditemukan bervariasi di sentra pertanaman kentang di Jawa Barat (Rancabali, Pangalengan, dan Bayongbong). Diagnosis virus berdasarkan gejala sulit untuk menentukan identitas suatu virus. Oleh karena itu penelitian ini bertujuan mendeteksi virus-virus pada tanaman kentang dengan teknik molekuler. Sebanyak 50 sampel daun dikoleksi secara acak dari tanaman kentang yang bergejala di setiap lokasi. Parameter yang diamati adalah gejala, kejadian penyakit, dan runutan DNA virus yang dominan ditemukan. Kejadian penyakit ditentukan dengan uji serologi menggunakan antiserum PVY, PVX, PVS, dan CMV, sedangkan deteksi asam nukleat dilakukan dengan RT-PCR dan perunutan DNA. Hasil penelitian menunjukkan bahwa gejala yang ditemukan bervariasi pada daun kentang, seperti vein clearing, vein banding, rugose, dan malformasi daun. Kejadian penyakit oleh PVY, PVX, PVS, dan CMV di Rancabali berturut-turut adalah 28%, 0%, 0%, dan 28%, di Pangalengan adalah 80%, 24%, 2%, dan 82%, serta di Bayongbong adalah 82%, 0%, 6%, dan 74%. RT-PCR menggunakan primer spesifik PVY dan CMV berhasil mengamplifikasi gen coat protein PVY dan CMV asal Bayongbong masing-masing berukuran ~800 pb dan ~650 pb. Homologi nukleotida dan asam amino PVY asal Bayongbong terhadap PVY dari negara lain berkisar 89,5–99,7% dan 92,0–100%. Homologi tertingginya yaitu dengan PVY-NTN asal Cina dan Jepang, sedangkan homologi nukleotida dan asam amino CMV asal Bayongbong terhadap CMV asal negara lain berkisar 87,6–96,9% dan 86,9–93,7%. Homologi tertingginya yaitu dengan CMV strain soybean stunt (S) asal Bogor (Indonesia). Kedua strain virus (PVY-NTN dan CMV-S) pertama kali terdeteksi pada kentang di Jawa Barat. Hasil penelitian menunjukkan bahwa teridentifikasinya kedua strain virus baru harus dipertimbangkan sebagai pembatas penting produksi kentang di Jawa Barat

Odontoglossum ringspot virus (ORSV) terdeteksi secara serologi dari tanaman bergejala maupun tidak bergejala pada banyak spesies anggrek yang diambil dari beberapa lokasi pertanaman anggrek di Pulau Jawa. Odontoglossum ringspot virus dilaporkan telah ditemukan pertama kali di Pulau Jawa, Indonesia. Penelitian bertujuan menguji respons ketahanan beberapa spesies anggrek komersial terhadap ORSV. Penelitian dilakukan di Rumah Kasa dan Laboratorium Virologi, Fakultas Pertanian, Institut Pertanian Bogor dari bulan Juni sampai November 2011. Tiga belas spesies anggrek diinokulasi secara mekanis dengan ORSV dalam percobaan di rumah kaca. Peubah pengamatan yang diamati adalah waktu inkubasi, kejadian penyakit, tipe gejala, dan titer ORSV yang dideteksi secara serologi dengan ELISA. Gejala khas infeksi ORSV muncul dengan kisaran tercepat pada 4–7 hari sampai 90 hari setelah inokulasi. Gejala pada daun bervariasi seperti lesio lokal, nekrosis, klorosis, dan bercak bercincin bergantung pada spesies anggrek dengan kejadian penyakit berkisar 40–100%. Titer ORSV berdasarkan ELISA menunjukkan nilai absorbansi antara 1,5–13 kali lebih tinggi dibandingkan tanaman kontrol sehat. Data ini menunjukkan bahwa dari 13 spesies anggrek yang diuji sebanyak 61,54% dikategorikan rentan dan 38,46% dikategorikan tahan terhadap infeksi ORSV. Hasil penelitian ini akan digunakan sebagai informasi untuk mendapatkan tanaman anggrek rentan yang dapat ditingkatkan ketahanannya dengan perlakuan asam salisilat.

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%.Keywords: Cucumis sativus, Dot immunobinding assay, Squash leaf curl China virus, Tomato leaf curl New Delhi virusABSTRAKSurvei 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.Kata kunci: Cucumis sativus, Dot immunobinding assay, Squash leaf curl China virus, Tomato leaf curl New Delhi virus.

Brome mosaic virus (BMV) purified from systemically infected barley leaves 8 weeks post-inoculation (p.i.) contained defective RNAs (D-RNAs). The D-RNAs were detected in total and virion RNAs extracted from infected plants at 8 weeks p.i. or later, but not before, when barley plants had been inoculated with virions either containing or lacking D-RNA. The D-RNAs were derived from genomic RNA3 by double or mainly single deletions in the 3a protein ORF, and formed a heterogeneous population. By using in vitro transcripts of D-RNA synthesized from full-length cDNA clones, the D-RNAs were shown to replicate in a helper virus-dependent manner and to be packaged into virions in barley protoplasts. Subgenomic RNA4 was produced from the D-RNA and the coat protein was also expressed. Existence of the D-RNAs together with BMV genomic RNAs in inoculated protoplasts decreased the accumulation of 3a protein but it had no apparent effect on the accumulation of BMV genomic RNA3 or the coat protein. This is the first report of naturally occurring D-RNAs generated during prolonged infection with BMV.

Yardlong bean (Vigna unguiculata subsp. sesquipedalis) is extensively cultivated in Indonesia for consumption as a green vegetable. During the 2008 season, a severe outbreak of a virus-like disease occurred in yardlong beans grown in farmers' fields in Bogor, Bekasi, Subang, Indramayu, and Cirebon of West Java, Tanggerang of Banten, and Pekalongan and Muntilan of Central Java. Leaves of infected plants showed severe mosaic to bright yellow mosaic and vein-clearing symptoms, and pods were deformed and also showed mosaic symptoms on the surface. In cv. 777, vein-clearing was observed, resulting in a netting pattern on symptomatic leaves followed by death of the plants as the season advanced. Disease incidence in the Bogor region was approximately 80%, resulting in 100% yield loss. Symptomatic leaf samples from five representative plants tested positive in antigen-coated plate-ELISA with potyvirus group-specific antibodies (AS-573/1; DSMZ, German Resource Center for Biological Material, Braunschweig, Germany) and antibodies to Cucumber mosaic virus (CMV; AS-0929). To confirm these results, viral nucleic acids eluted from FTA classic cards (FTA Classic Card, Whatman International Ltd., Maidstone, UK) were subjected to reverse transcription (RT)-PCR using potyvirus degenerate primers (CIFor: 5′-GGIVVIGTIGGIWSIGGIAARTCIAC-3′ and CIRev: 5′-ACICCRTTYTCDATDATRTTIGTIGC-3′) (3) and degenerate primers (CMV-1F: 5′-ACCGCGGGTCTTATTATGGT-3′ and CMV-1R: 5′ ACGGATTCAAACTGGGAGCA-3′) specific for CMV subgroup I (1). A single DNA product of approximately 683 base pairs (bp) with the potyvirus-specific primers and a 382-bp fragment with the CMV-specific primers were amplified from ELISA-positive samples. These results indicated the presence of a potyvirus and CMV as mixed infections in all five samples. The amplified fragments specific to potyvirus (four samples) and CMV (three samples) were cloned separately into pCR2.1 (Invitrogen Corp., Carlsbad, CA). Two independent clones per amplicon were sequenced from both orientations. Pairwise comparison of these sequences showed 93 to 100% identity among the cloned amplicons produced using the potyvirus-specific primers (GenBank Accessions Nos. FJ653916, FJ653917, FJ653918, FJ653919, FJ653920, FJ653921, FJ653922, FJ653923, FJ653924, FJ653925, and FJ653926) and 92 to 97% with a corresponding nucleotide sequence of Bean common mosaic virus (BCMV) from Taiwan (No. AY575773) and 88 to 90% with BCMV sequences from China (No. AJ312438) and the United States (No. AY863025). The sequence analysis indicated that BCMV isolates from yardlong bean are more closely related to an isolate from Taiwan than with isolates from China and the United States. The CMV isolates (GenBank No. FJ687054) each were 100% identical and 96% identical with corresponding sequences of CMV subgroup I isolates from Thailand (No. AJ810264) and Malaysia (No. DQ195082). Both BCMV and CMV have been documented in soybean, mungbean, and peanut in East Java of Indonesia (2). Previously, BCMV, but not CMV, was documented on yardlong beans in Guam (4). To our knowledge, this study represents the first confirmed report of CMV in yardlong bean in Indonesia and is further evidence that BCMV is becoming established in Indonesia. References: (1) J. Aramburu et al. J. Phytopathol. 155:513, 2007. (2) S. K. Green et al. Plant Dis. 72:994, 1988. (3) C. Ha et al. Arch. Virol. 153:25, 2008. (4) G. C. Wall et al. Micronesica 29:101, 1996.

In surveys conducted in May 2008 in Warung Kondang, Cianjur, West Java, tomato plants ( Solanum lycopersicum ) growing in farmers’ fields showed stunting and leaf symptoms of either bronzing or general chlorosis with vein-banding. In addition, chilli peppers ( Capsicum spp.) were observed with chlorosis and vein-banding symptoms in Salabintana, Sukabumi, West Java. Finally, peanut plants ( Arachis hypogaea ) showing chlorotic rings and necrosis on leaves were observed in a field near to the Bogor Agricultural University Campus, Darmaga Bogor. All these symptoms suggested the possible involvement of tospoviruses. To identify the viruses involved, leaves with symptoms were pressed onto FTA classic cards [FTA ® Classic Card, Whatman International Ltd.] and shipped to Washington State University, with the appropriate permit from USDA-APHIS-PPQ. Nucleic acids were recovered from the cards using a sample extraction protocol (Alabi et al ., 2008) and tested by one-tube, single-step reverse transcriptionpolymerase chain reaction (RT-PCR) using degenerate ‘universal’ tospovirus primers [Upstream primer: 5 ′ -CCTTTAACAGT(A/T/G)GAAACAT-3 ′ and Downstream primer: 5 ′ -CAT(A/T/G)GC(A/G)CAAGA(A/G)TG(A/G)TA(A/ G)ACAGA-3 ′ ] conserved in the L RNA segment of tospoviruses (Chu et al ., 2001). A DNA fragment of approximately 800 base pairs was amplified from the tomato, pepper and peanut samples. Each was cloned separately into pCR 2.1-TOPO vector (Invitrogen). Three independent clones from each sample were sequenced in both directions. A comparison of the nucleotide sequences obtained from the tomato (GenBank Accession No. FJ 177301) and chilli pepper samples (FJ 177302) was made with corresponding sequences of tospovirus L-RNA deposited in GenBank. This analysis showed 96 and 97% nucleotide sequence identity with Tomato spotted wilt virus (TSWV) isolates from Hawaii, USA (AY070218) and Japan (AB198742), respectively. The sequences obtained from tomato and chilli shared only 93% identity between them, indicating that the Indonesian TSWV isolates from tomato and pepper may be distinct strains. An analysis of the nucleotide sequence obtained from the peanut sample (FJ177300) showed 94% sequence identity with corresponding L RNA sequence of a Peanut bud necrosis virus (PBNV) isolate from India (AF025538). These results confirm for the first time that two distinct tospoviruses, TSWV and PBNV, occur in Indonesia.