Effectivity of Single Isolates, Mixtures, and Consortium of Endophytic Bacteria Against Fusarium solani and Meloidogyne spp. in Vitro

Effectivity of Single Isolates, Mixtures, and Consortium of Endophytic Bacteria Against Fusarium solani and Meloidogyne spp. in Vitro Fusarium solani and Meloidogyne spp. is known as pathogens associated with pepper yellow disease. The use of endophytic bacteria for controlling this disease needs to be evaluated. Therefore, this study was conducted with the aim of evaluating the biocontrol activity of endophytic bacterial isolates applied singly (B. siamensis and B. velezensis), mixed (B. subtilis and B. wiedmannii) and consortium (PTM3) in suppressing F. solani and Meloidogyne spp. in vitro. Research methods included the isolation of F. solani and extraction of Meloidogyne spp. from the roots of infected plant, pathogenicity test, dual culture and mortality test, as well as physiological assay of endophytic bacterial isolates. The isolates of F. solani and Meloidogyne spp. proven to be pathogenic in pepper seedlings and causing yellow symptoms. Four isolates of endophytic bacteria were able to inhibit mycelium growth of F. solani. The highest inhibition on TSA medium was shown by a single isolate of B. siamensis, i.e. 57.25%; while on PDA medium was shown by mixed isolates of B. subtilis and B. wiedmannii, i.e. 56.47%. Application of B. velezenziz caused the highest mortality rate of Juvenile larval 2 Meloidogyne spp., i.e. 75.24%. Both B. siamensis and B. velevenzis isolates showed protease and cellulase activity; while mixed isolates of B. subtilis and B. wiedmannii and the PTM3 consortium isolates showed chitinase, protease and cellulase activity.Fusarium solani dan Meloidogyne spp. merupakan dua jenis patogen yang berasosiasi dengan penyakit kuning lada. Pemanfaatan bakteri endofit dalam pengendalian penyakit kuning lada perlu dievaluasi. Oleh karena itu, penelitian dilakukan dengan tujuan mengevaluasi aktivitas biokontrol isolat bakteri endofit yang diaplikasikan secara tunggal (B. siamensis dan B. velezensis), campuran (B. subtilis dan B. wiedmannii) dan konsorsium (PTM3) dalam menekan F. solani dan Meloidogyne spp. secara in vitro. Metode penelitian meliputi isolasi F. solani dan ekstraksi Meloidogyne spp. dari akar tanaman lada, uji patogenisitas, uji dual kultur dan uji mortalitas, serta karakterisasi fisiologi isolat bakteri endofit. Isolat F. solani dan Meloidogyne spp. terbukti bersifat patogenik pada bibit lada dan menyebabkan munculnya gejala penyakit kuning. Empat isolat bakteri endofit yang diuji mampu menghambat pertumbuhan miselium F. solani. Penghambatan tertinggi pada medium TSA ditunjukkan oleh isolat tunggal B. siamensis, yaitu sebesar 57.25%; sedangkan pada medium ADK ditunjukkan oleh isolat campuran B. subtilis dan B. wiedmannii, yaitu sebesar 56.47%. Mortalitas larva juvenil 2 Meloidogyne spp. mengalami peningkatan tertinggi pada perlakuan B. velezenziz, yaitu sebesar 75.24%.  Isolat B. siamensis dan B. velevenzis menunjukkan aktivitas protease dan selulase; sedangkan isolat campuran B. subtilis dan B. wiedmannii serta isolat konsorsium PTM3 menunjukkan aktivitas kitinase, protease dan selulase