ELIMINASI Potyvirus PENYEBAB PENYAKIT MOSAIK PADA TANAMAN NILAM DENGAN KULTUR MERISTEM APIKAL DAN PERLAKUAN AIR PANAS PADA SETEK BATANG

Abstract

ABSTRAK Minyak nilam merupakan salah satu bahan baku parfum multifungsi yang bernilai tinggi. Budidaya dan pengembangan tanaman nilam terkendala oleh serangan Potyvirus yang menyebabkan penyakit mosaik. Penelitian ini bertujuan untuk mendapatkan benih nilam bebas virus dengan metode kultur meristem apikal dan perlakuan air panas pada setek batang. Penelitian dilaksanakan mulai Januari sampai Desember 2010 di Laboratorium Virologi Tumbuhan, Institut Pertanian Bogor dan Rumah Kasa Hama dan Penyakit, Balai Penelitian Tanaman Obat dan Aromatik (Balittro) di Bogor. Bahan tanaman yang digunakan adalah tiga varietas nilam (Sidikalang, Lhokseumawe, Tapak Tuan). Penelitian terdiri atas (1) Eliminasi Potyvirus pada tanaman nilam menggunakan kultur meristem apikal dan (2) Eliminasi Potyvirus pada setek batang nilam dengan perlakuan air panas. Percobaan pertama disusun menggunakan rancangan acak lengkap dengan perlakuan 3 varietas nilam dan 2 tipe eksplan (meristem apikal dan batang terminal), dan diulang 10 kali. Parameter yang diamati adalah persentase pertumbuhan, waktu inisiasi, tinggi, dan warna tunas, serta persentase tanaman yang terinfeksi Potyvirus. Percobaan kedua menggunakan air panas pada tiga tingkatan suhu (50, 55, dan 60 o C) dan tingkatan waktu perendaman (10, 20, dan 30 menit). Percobaan disusun menggunakan rancangan acak lengkap dengan 10 perlakuan dan 10 ulangan. Tanaman nilam dipelihara selama 8 minggu dan dilakukan pengamatan tinggi setek yang tumbuh dan daun yang bergejala mosaik. Hasil penelitian menunjukkan bahwa tanaman nilam, yang diperbanyak dari kultur meristem apikal ukuran 0,5-1 mm, menghasilkan 33,3-99,9% tanaman bebas virus. Perendaman setek batang nilam di dalam air panas pada suhu 50-60 o C selama 10-30 menit tidak dapat mengeliminasi Potyvirus yang menginfeksi ketiga varietas nilam yang diuji. Setek batang nilam varietas Tapak Tuan dan Lhokseumawe lebih toleran terhadap air panas dibandingkan Sidikalang tetapi daya tumbuhya semakin menurun seiring semakin lama waktu perendaman. Teknik kultur meristem apikal berpotensi untuk menghasilkan setek nilam yang bebas virus. Kata kunci : kultur meristem apikal, perlakuan air panas, Pogostemon cablin, Potyvirus ABSTRACT Patchouli oil produced by patchouli plant is one of multifunctioning perfume’s raw materials and has high economic value. One important constraint during its cultivation is infection by Potyvirus causing serious mosaic disease. This study was conducted to develop a technique to produce virus-free cutting seeds using apical meristem culture and hot water treatment on stem cutting. The study was carried out from January to December 2010 in Plant Virology Laboratory of Bogor Agricultural University and Pest and Diseases screen house of Indonesian Medicinal and Aromatic Crops Research Institute (Balittro) in Bogor. Three varieties of patchouli plant, i.e. Sidikalang, Lhokseumawe, and Tapak Tuan, were used in this study. The study consisted of (1) Elimination Potyvirus in cuttings of patchouli through apical meristem culture and (2) Elimination Potyvirus in stem cuttings of patchouli with hot water treatment. The first experiment was arranged using completely randomized design with treatments of three patchouli varieties and two explant types (apical meristem and stem terminal), and it was replicated 10 times. Parameters observed were bud growth percentage, initiation time, height, and color, and also percentage of plant infected by Potyvirus. The second experiment applied hot water at three temperature levels (50, 55, and 60 o C) and submersion periods (10, 20, and 30 minutes). It was arranged using randomized complete design, consisting of 10 treatments with 10 plants for each treatment. The patchouli plants were maintained for 8 weeks and observations were made for height of growing cuttings and leaves with mosaic symptoms. The results showed that the patchouli plants propagated from apical meristem culture of 0.5-1 mm in sizes yielded 33.3-99.9% virus-free plants. Submersion of patchouli stem cutting seeds in hot water of 50-60 o C and soaking period of 10-30 minutes could not eliminated the infecting Potyvirus on patchouli the three tested varieties. Cutting seeds of Lhokseumawe and Tapak Tuan varieties were more tolerant to hot water than Sidikalang one. However, their ability to grow decreased in line with longer submersion time period. Apical meristem culture technique is potential to produce virus-free cutting seeds of patchouli. Key words: apical meristem culture, hot water treatment, Pogostemon cablin, Potyvirus