Biological control of grey mould disease (Botrytis cinerea Pers.) on grape by antagonist bacteria

Objective: In this study, it was aimed to investigate the isolation of antagonist bacteria from the vineyard areas of Manisa province Sarıgöl district and the possibilities of using them in biological control against Botrytis cinerea. Material and Methods: Pathogen and candidates antagonist bacteria for the study were isolated from the field using appropriate methods. Identification, mechanism of action and species identification of antagonistic bacteria were made. Inhibition rates of antagonist bacteria were determined by dual culture test. The sensitivity of the antagonist bacteria to Azoxystrobin and 37.5% Cyprodinil + 25% Fludioxonil active substances were tested. Biological activity tests were applied on the fruit and plant in the growth chamber with some antagonist isolates selected according to the test results. Results: In the study, a total of 160 antagonist bacteria candidates were obtained and 17 bacteria were determined to be antagonists. Antagonist bacteria showed 6.8% - 80.1% efficacy against Botrytis cinerea in the dual culture test. Antagonist bacterium A7Len4 provided the highest inhibition rate of 78.99% in the biological activity test in fruit. The antagonist bacteria A7Len4, A1Len4 and A8Len1 protected the vine cuttings between 71.43% and 80.95% against Botrytis cinerea in the biological activity test in the climate chamber. Conclusion: Antagonistic bacteria effective on the disease were isolated. The activity of the obtained antagonistic bacteria against Botrytis cinerea pathogen has been demonstrated. Key Words: Antagonist Bacteria, Biological control, Botrytis cinerea, Viticulture.