DETEKSI SECARA SEROLOGI DAN MOLEKULER BEBERAPA JENIS VIRUS YANG BERASOSIASI DENGAN PENYAKIT MOSAIK TANAMAN NILAM (Pogostemon cablin Benth)

ABSTRAK Penyakit mosaik pada tanaman nilam disebabkan oleh beberapa jenis virus, yaitu Potyvirus, Potexvirus, Cucumber mosaic virus (CMV), dan Broad bean wilt virus 2 (BBWV2). Penelitian ini bertujuan untuk mengidentifikasi secara serologi dan molekuler virus-virus yang berasosiasi dengan gejala mosaik pada nilam di KP. Manoko, KP. Cicurug dan lahan petani di Cijeruk. Sampel daun nilam baik yang menunjukkan gejala mosaik atau pun tidak diambil dari setiap lokasi penanaman masing–masing sebanyak 30 sampel. Kejadian penyakit ditentukan melalui deteksi serologi dengan Direct-ELISA dan Indirect-ELISA terhadap sampel menggunakan empat antiserum, yaitu CMV, Cymbidium mosaic virus (CymMV), Potyvirus, dan BBWV2. Deteksi molekuler dengan RT-PCR dilakukan untuk mengonfirmasi virus baru yang ditemukan. Hasil penelitian menunjukkan bahwa gejala infeksi virus yang ditemukan pada nilam bervariasi, yaitu mosaik lemah, mosaik kuning hijau, mosaik dengan penebalan, mosaik dengan malformasi daun, dan bintik kuning. Secara serologi, kejadian virus pada setiap kebun bervariasi. Di KP Manoko, Potyvirus dan BBWV2 lebih dominan (100%) dibandingkan CymMV. Di KP Cicurug, kejadian Potyvirus dan CMV terlihat lebih dominan (83,3 dan 80%) dibandingkan BBWV2 dan CymMV, sedangkan di Cijeruk, BBWV2 lebih dominan (90%) dari Potyvirus (50%) dan CMV (13,3%). Hasil RT- PCR dengan primer degenerate BBWV, diidentifikasi BBWV2 pada sampel daun nilam dari Manoko, Cicurug, dan Cijeruk, sedangkan dengan primer general Potexvirus, diidentifikasi CymMV hanya dari sampel daun nilam dari asal Manoko. Hasil penelitian ini merupakan laporan pertama tentang BBWV2 dan CymMV pada tanaman nilam di Jawa Barat yang mengindikasikan bahwa virus merupakan kendala utama pada perbenihan nilam yang harus segera diatasi. Kata kunci: BBWV2, CymMV, mosaik, Pogostemon cablin Benth, PCR ABSTRACT Mosaic symptoms on patchouli plant are associated with several viruses, i.e. Potyvirus, Potexvirus, CMV, and BBWV2. The objective of the study was to detect virus(es) associated with mosaic symptoms on patchouli at the the patchouli seed nurseries, in Manoko, Cicurug, and Cijeruk. Thirty leaf samples either showing typical symptomatic mosaic or asymptomatic were taken from each location. Serological testing by Direct-ELISA and Indirect-ELISA using four antisera namely CMV, Cymbidium mosaic virus (CymMV), Potyvirus, and BBWV2 was carried out to test the incidence of each virus. Molecular detection by RT-PCR was performed to confirm the new virus(es). The results showed that symptoms of 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 seed nurseries. In Manoko, Potyvirus, and BBWV2 were more dominant (100%) compared with CymMV. In Cicurug, Potyvirus and CMV were more 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 pair of BBWV was succesfully identified BBWV2 from Manoko, Cicurug, and Cijeruk samples, whereas by using Potexvirus general primary, CymMV was identified only from Manoko samples. BBWV2 and CymMV were first reported to infect patchouli in West Java. The result indicate that virus(es) are the major constraint on patchouli seed that should be managed immediately. Key words: BBWV2, CymMV, mosaic, Pogostemon cablin Benth, PCR