Keefektifan berbagai formulasi plant growth promoting Rhizobacteria (PGPR) dan Bakteri endofit terhadap penyakit layu bakteri yang disebabkan oleh ralstonia solanacearum pada tomat

Abstract

Ralstonia solanacearum causes the most serious bacterial wilt disease in Solanaceae plants. Various attempts have been made but pathogen is still difficult to be controlled. Aplication of plant growth promoting rhizobacteria (PGPR) and endophytic bacterial formulation are expected as an alternative in controlling wilt disease. The aim of this research was to evaluate the effectiveness of various PGPR and endophytic bacterial based formulations on bacterial wilt caused by Ralstonia solanacearum in tomato plants in the field. Biocontrol formulations were applied by pouring to the tomato seedling after transplanting. PGPR bacteria used in this experiment was Bacillus subtilis AB89, which belonged to the collection of Plant Bacteriology Laboratory, Department of Plant Protection, Faculty of Agriculture, Bogor Agricultural University, which the endophytic bacteria used was Staphylococcus epidermidis BC4. Some of the formulation of bacteria were added with carboxy methyl celullose (CMC) 1%. Based on the value of Area Under Disease Progress Curve (AUDPC), the treatment of PGPR and endophytic bacterial formulations did not significantly different compare with control. Based on the index of disease suppression, single treatment of S. epidermidis (B0S100) gave the best suppression to the bacterial wilt. Single treatment of S. epidermidis (B0S100) had a suppression index of 40.96%. Data of AUDPC, heading dry weight, root dry weight and harvested tomato fruit weight showed that bacterial formulations with CMC treatment did not significantly different compare with treatment of bacterial formulations without CMC.

Ralstonia solanacearum adalah penyebab penyakit layu bakteri yang paling serius pada tanaman Solanaceae. Berbagai pengendalian telah dilakukan tetapi patogen masih sulit dikendalikan. Aplikasi formulasi plant growth promoting rhizobacteria (PGPR) dan bakteri endofit diharapkan menjadi alternatif dalam mengendalikan penyakit layu bakteri. Penelitian ini bertujuan untuk mengevaluasi keefektifan berbagai formulasi PGPR dan bakteri endofit terhadap penyakit layu bakteri yang disebabkan oleh Ralstonia solanacearum pada tanaman tomat di lapangan. Formulasi biokontrol dilakukan dengan menyiram bibit tomat setelah pindah tanam. Bakteri PGPR yang digunakan pada penelitian adalah Bacillus subtilis AB89, diperoleh dari koleksi Laboratorium Bakteriologi Tumbuhan, Departemen Proteksi Tanaman, Fakultas Pertanian, Institut Pertanian Bogor. Bakteri endofit yang digunakan yaitu Staphylococcus epidermidis dengan kode isolat BC4. Formulasi yang digunakan sebagian mengandung carboxy methyl celullose (CMC) 1%. Berdasarkan nilai Area Under Disease Progress Curve (AUDPC), aplikasi formulasi bakteri PGPR dan bakteri endofit tidak berbeda nyata dibandingkan dengan kontrol. Berdasarkan index penekanan penyakit, perlakuan S. epidermidis secara tunggal (B0S100) memberikan penekanan yang paling baik terhadap penyakit layu bakteri. Index penekanan S. epidermidis secara tunggal (B0S100) sebesar 40.96%. Data AUDPC, bobot kering tajuk, bobot kering akar, dan bobot hasil panen buah menunjukkan bahwa perlakuan formulasi bakteri dengan penambahan CMC tidak berbeda nyata dibandingkan dengan perlakuan formulasi bakteri tanpa penambahan CMC.