Potensi Bakteri Kitinolitik untuk Pengendalian Penyakit Busuk Pangkal Batang Lada ( Phytophthora capsici) - Rita Harni; Widi Amaria (Pusat Penelitian dan Pengembangan Perkebunan, 2012)
Salah satu kendala dalam peningkatan produktivitas lada adalah adanya serangan penyakit busuk pangkal batang yang disebabkan oleh Phytophthora capsici, akibat infeksi patogen ini dapat menurunkan hasil lada 10-15% setiap tahunnya. Penelitian potensi bakteri kitinolitik untuk mengendalikan penyakit busuk pangkal batang lada telah dilakukan di Laboratorium dan Rumah Kaca Kelompok Peneliti Proteksi Tanaman Balai Penelitian Tanaman Rempah dan Aneka Tanaman Industri dari bulan Juni-November 2011. Bakteri kitinolitik yang digunakan merupakan isolat terbaik hasil seleksi bakteri kitinolitik di laboratorium. Isolat diisolasi dari beberapa tanaman yaitu lada, bintaro dan kelapa sawit. Isolat yang digunakan adalah: LP4, BP2, LB12, LB19, LB20, LB31, LL5, LL18, dan E10. Sebagai pembanding digunakan isolat bakteri kitinolitik TT2 yang sudah teruji keefektifannya. Penelitian terdiri dari 3 kegiatan yaitu (1) Analisis ekspresi kitinase, (2) Uji Antagonis bakteri kitinolitik terhadap P. capsici in vitro, dan (3) Pengujian isolat bakteri kitinolitik terhadap P. capsici pada tanaman lada di rumah kaca. Hasil penelitian diperoleh 4 isolat dengan aktivitas kitinase tinggi yaitu BP2, LB19, LL5, dan LL18, sedangkan 6 isolat lainnya mempunyai aktivitas kitinase rendah sampai sedang. Kemampuan antagonis ke-10 isolat bakteri kitinolitik terhadap P. capsici memperlihatkan daya antagonis yang sama yaitu 64,4-85,6%, tetapi pengaruhnya terhadap P. capsici di rumah kaca diperoleh 3 isolat (E10, BP2, LP4) yang potensial menekan penyakit BPB lada dengan intensitas serangan 34,33-43,97%, sedangkan pada kontrol 73,37%. Beberapa isolat bakteri kitinase dapat meningkatkan pertumbuhan tanaman lada di banding dengan kontrol. Potential of chytinolytic bacteria to control Phytophthora capsici (foot rot disease) on black pepperABSTRACTOne of many problems in increasing productivity of black pepper is foot rot disease caused by Phytophthora capsici. This pathogen infection may reduce 10-15% of yields each year. A study on potential chitinolytic bacteria to control foot rot disease of black pepper was carried out at Laboratory and Greenhouse of Plant Protection, Indonesian Research Institute for Spice and Industrial Crops, from June to November 2011. Chitinolytic bacterial isolates used is the best ones of some selected chitinolytic bacteria. The isolates were isolated from different plants, namely black pepper, bintaro and palm oil. In these experiments isolates used were LP4, BP2, LB12, LB19, LB20, LB31, LL5, LL18, and E10, while its control was chitinolytic bacterial isolate TT2, an isolate having high effectiveness. The study consist of three activities: (1) Analysis of chitinase expression, (2) Test antagonists of chitinolytic bacteria against P. capsici in vitro (3) Testing of chitinolytic bacteria isolates against P. capsici on black pepper in greenhouse. Results have identified 4 isolates (BP2, LB19, LL5, and LL18) having high in chitinase expression, whereas six other isolates have low to medium in chitinase expression. Antagonistic ability against P. capsici from all isolates (10 isolates) showed the same inhibitory ranging from 64.4 to 85.6%, but its effect against P. capsici at greenhouse was obtained 3 isolates (E10, BP2, LP4) which have suppressive potential to foot rot disease of black pepper with attacks intensity of 34.33 to 43.97% level, while that of control was 73.37%. The ten isolates also increased better growth of black pepper compared with the control.