Pengendalian hayati penyakit layu bakteri (Ralstonia solanacearum) pada solanaceae dengan strain avirulen dan pseudomonas putida strain PF 20

NURCAHYANTI, Suhartiningsih Dwi, Dr. Ir. Triwidodo Arwiyanto, M.Sc

2008 | Tesis | S2 Fitopatologi

Penelitian pengendalian hayati penyakit layu bakteri (Ralstonia solanacearum) pada Solanaceae dengan strain avirulen dan Pseudomonas putida Strain Pf 20, bertujuan untuk mendapatkan strain R. solanacearum avirulen penghasil bakteriosin berdaya hambat besar dan berpektrum luas yang kompatibel dengan Pf 20. Hasil penelitian menujukkan bahwa dari 161 isolat R. solanacearum yang diisolasi dari berbagai tanaman solanaceae diperoleh hasil isolat R. solanacearum nomor 127 (Rs 127) mempunyai daya hambat besar (12,62 mm) dan spektrum terluas (86,15%). Rs 127 virulen dan Rs 127 avirulen kompatibel dengan Pf 20 pada medium YPGA dan CPG namun tidak kompatibel pada medium Kings’B. Identifikasi Rs 127 dan Rs 127 avirulen, dan Rs T (isolat terong yang digunakan sebagai Challenge) menujukkan sifat-sifat yang termasuk ke dalam ras 1 dan biovar 3. Uji fisiologi dan biokimia menunjukkan sifat-sifat yang sama seperti ang dideskripsikan oleh peneliti sebelumnya. Rs 127, Rs 127 avirulen, dan Pf 20 mampu menghambat RsT secara in vitro. Pengujian rumah kaca menunjukkan bahwa pencelupan akar tanaman terung dengan suspensi bakteri Rs127 avirulen dan Pf 20 secara tunggal maupun kombinasi pada konsentrasi 108 cfu/ml dan 109 cfu/ml dapat menekan penyakit dan memperpanjang masa inkubasi, serta meningkatkan berat basah dan berat kering batang dan akar tanaman.

Research on biological control of Solanaceous bacterial wilt disease with avirulent strain of Ralsonia solanacearum and P. putida strain Pf 20 was aimed at selecting R. solanacearum avirulen as the producer of bacteriocin with huge inhibiting factor and broad spectrum compatible to Pf 20. Result of the research showed that of 161 R. solancearum isolated from various solanaceae crops, R. solancearum isolate number 127 (Rs 127) was the isolate whose inhibition factor (12,62 mm) was huge and whose spectrum (86,15%) was the most expansive. On the one hand, it was obvious that virulent and avirulent strain of Rs 127 were compatible to Pf 20 on YPGA and CPG medium. On the other hand, they were not compatible on Kings’B medium. Identification on virulence and avirulence Rs127 and Rs T (eggplant isolate used as challenge) demonstrated that their characteristics included in race 1 and biovar 3. Physiological and biochemical tests confirmed the same characteristics as described by the previous researchers. Avirulent and virulent strain of Rs127 and Pf 20 inhibited Rs.T in vitro . The glasshouse test showed that dipping eggplant and pepper root in bacterial suspension of avirulent Rs 127 and Pf 20, both single and combination, in 108 cfu/ml concetration and 109 cfu/ml was able to press the disease and lengthen incubation period. The treatment also increased the fresh weight and dry weight of shoot and root.

Kata Kunci : Ralstonia solanaserum,Strain avirulen,Pseudomonas putida pf 20