Deteksi Ganoderma secara molekuler pada kebun kelapa sawit yang diberi perlakuan biofungisida Ganor (Molecular detection of Ganoderma on oil palm plantation treated with Ganor biofungicide)

AbstractGanor organic fungicide potentially reduces Ganoderma, a pathogenic fungus causing basal stem rot disease. Application of Ganor on oil palm trees in the plantation attacked Ganoderma, inhibits the growth of Ganoderma fruiting bodies, improves rooting and stimulates the opening of the spear leaf. This study aims to identify molecularly the presence of Ganoderma in oil palm trees that have been attacked by Ganoderma routinely treated with Ganor for three months. Molecular analysis was performed by PCR using Ganoderma specific primers. The analysis results of sample from trunks and roots of oil palm, indicating that the Ganoderma infected oil palm which has been treated with Ganor, were relatively free (96.4%) of Ganoderma. Of the 28 samples examined of treated plants, 27 samples did not indicate the presence of Ganoderma specific DNA band. On the other hand, the untreated oil palm trees infected by Ganoderma were still detected by the appearence of DNA bands specific to Ganoderma. The results of molecular analysis indicated that Ganor treatments can effectively reduce the attack rate of Ganoderma in oil palm trees in the plantation infected by Ganoderma. However, the use of the molecular technique for early detection needs to be further tested to evaluate its consistency prior to introduction to the commercial growers. The reproducibility can be confirmed by repeating the experiment using more samples. Ganor effectiveness in curing oil palm trees infected by Ganoderma, maybe indicated by the ability of the reproductive organs to develop, particularly female flowers. The sex ratio of Ganor treated oil palms was clearly higher than that of control palms in 10 to 12 weeks after the treatment.[Keywords: organic fungicides, stem rot, molecular analysis, Elais guinensis Jack.] AbstrakFungisida organik Ganor berpotensi mengurangi serangan Ganoderma, cendawan patogenik penyebab penyakit busuk pangkal batang. Aplikasi Ganor pada tanaman kelapa sawit di kebun yang terserang Ganoderma, menghambat pertumbuhan tubuh buah Ganoderma, memper-baiki perakaran dan merangsang pembukaan daun tombak. Penelitian ini bertujuan untuk mengidentifikasi secara molekuler adanya Ganoderma pada tanaman kelapa sawit terserang Ganoderma yang telah mendapat perlakuan Ganor secara rutin selama tiga bulan. Analisis molekuler dilakukan dengan teknik PCR menggunakan primer DNA spesifik Ganoderma. Hasil analisis sampel batang dan akar tanaman kelapa sawit, menunjukkan bahwa tanaman Perlakuan, yaitu kelapa sawit terserang Ganoderma yang telah mendapat perlakuan Ganor, 96,4% bebas Ganoderma. Dari 28 sampel tanaman Perlakuan yang diperiksa, 27 sampel tidak menunjukkan adanya pita DNA spesfik Ganoderma. Sementara itu pada tanaman Kontrol, yaitu tanaman kelapa sawit terserang Ganoderma dan tidak mendapat perlakuan Ganor, 100% masih terdeteksi adanya Ganoderma. Dari 7 sampel tanaman kontrol yang diperiksa semuanya menunjukkan adanya pita DNA spesifik Ganoderma. Hasil analisis molekuler ini mengindikasikan bahwa perlakuan Ganor efektif mengurangi tingkat serangan Ganoderma pada tanaman kelapa sawit di kebun yang terinfeksi Ganoderma. Namun demikian, untuk lebih meyakinkan praktisi perkebunan, penggunakan teknik molekuler ini masih perlu diuji lebih lanjut terkait konsistensinya. Reprodusibilitas dapat dikonfirmasi dengan mengulangi percobaan menggunakan lebih banyak sampel. Efektivitas Ganor dalam menyehatkan tanaman kelapa sawit terserang Ganoderma ini, terindikasi juga dari perkembangan organ reproduktifnya. Sex ratio meningkat dalam waktu 10 hingga 12 minggu setelah perlakuan.[Kata Kunci: fungisida organik, busuk pangkal batang, analisis molekuler, Elais guinensis Jack. ]