Biological control of fig endosepsis with antagonistic bacteria

"Fig endosepsis" caused by Fusarium spp. is one of the most important diseases of fig fruits in Turkey. The study aims at determining in vitro and in vivo effectiveness of antagonistic bacteria isolated from male and female fig fruits against Fusarium spp causing Fig Endosepsis in Aydın Province. Fusarium spp was isolated from diseased caprifigs and bacteria were isolated from healthy caprifigs collected from Aydın province (Bozdoğan, Nazilli and Erbeyli Fig Research Institute). Pathoenicity of purified Fusarium isolates was evaluated on detached caprifig fruits and identified by PCR analysis with ITS1/ITS4 and ef1/ef2 primers, followed by sequencing and NCBI BLASTn analysis. Twenty out of 138 purified bacterial strains showing the highest inhibitory activity against 3 Fusarium isolates in dual culture tests were also identified by 16S rDNA sequencing after amplification of the gene by PCR with the primers 27F/1390R. Twenty selected bacterial strains were also tested for the effect on fig wasp (Blastophaga psenes) emergence and the pathogenicity of Fusarium verticilloides on detached caprifig fruits. At the end of study, 30 Fusarium strains were identified as Fusarium solani, 15 Fusarium proliferatum, 9 Fusarium verticillioides and 13 Fusarium sp. In the orchard experiments, caprifig fruits treated with 4 selected bacterial strains and one commercial fungicide (prokloraz) were used by pollination in a comercial fig (cv Sarilop) orchard of Kızıldere willage of Nazilli town. Experiments were conducted by using randomized-plot design 7 treatments (4 bacterium, 1 fungicide, 1 untreated control, 1 farmer condition) with 3 replicates. Orchard experiments resulted in decrease in the fig endosepsis by 72% from the application of Pseudomonas sp ((BB7-B4), 62.23% of Pantoea sp. (Boğa in 1), 52,77% of Serratia sp. (Kaba ilek B2 ), 42.77% of Pseudomonas sp. (BEB 10 B2T). Commercial fungicide (prokloraz) treatment showed 34.31% activity against fig endosepsis in the orchard experiment. Key words: Ficus carica, fig endosepsis, Sarılop, caprific, biocontrol, Fusarium spp.