Detection of bacterial stem rot disease in corn in Adana and Osmaniye provinces and investigation of biological control possibilities

The causal agent bacterial microorganism Dickeya sp. causes Bacterial Stalk Rot disease on corn plants. Within the scope of this study, it was aimed to detection of Bacterial Stalk Rot disease of corn in Adana and Osmaniye provinces and to investigate biological control possibilities. The prevalences of the disease in the fields examined were 8%, 9% and %40 in Ceyhan, Kozan and Kadirli counties, respectively. The disease incidences were between 8-15% ratios in disease contaminated fields. The suspicious bacterium Dickeya sp. isolated from diseased corn stalks, and then identified by using traditional methods, MALDI-TOF MS and PCR tests. The pathogenic bacterium did not detect in soil, however, the pathogen detected in irrigation water. Based on the study, pathogen contaminated irrigation water have a risk for corn fields. The research on the biological control of the disease was carried out with 332 candidate antagonists and it was determined that 84 representative antagonists had antibacterial effect on Dickeya sp. in in vivo conditions. In semi in vivo experiments on potato slices, six out of 84 antagonists caused rot on potato slicesless than the positive control, and two antagonists (strain X77 and strain OG/1-12) suppressed rot development by 56% and 27% ratios, respectively. Two antagonistic bacteria were identified as Bacillus sp. by MALDI-TOF MS analysis. Because of the non effective chemical control of the disease, having of an effective local antagonist is a promising result for biocontrol research. Keywords: Corn, Bacterial Stalk Rot, Dickeya sp., Biological control.