Study on antibacterial effect of marjoram (Origanum vulgare L) essential oil on bacteria causing citrus canker

Subject Areas : Bacteriology

Maryam Shahivand ¹ , Mojtaba Rezaei Ahmadabadi ² , Eidi Bazgir ³ , Rostam Yazdani Bioki ⁴

1 - M.Sc., Department of Plant Pathology, Faculty of Agriculture, Lorestan University, Khoramabad, Iran.
2 - M.Sc., Faculty of Agriculture, Payam Noor University, Tehran, Iran
3 - Associate Professor, Department of Plant Pathology, Faculty of Agriculture, Lorestan University, Khoramabad, Iran.
4 - Assistant Professor, National Salinity Research Center, Agricultural Research, Education and Extension Organization (AREEO), Yazd, Iran.

Received: 2016-10-27 Accepted : 2017-01-26 Published : 2017-05-22

Keywords: Antimicrobial, Medical plants, Inhibition and lethal doses,

Abstract :

Background & Objectives: Citrus bacterial canker (CBC) disease is one of the main citrus diseases that is caused by Xanthomonas citri subsp. citri. The disease has been reported from several citrus- growing regions of Iran. Due to the high loss incurred by the disease, its control is very much needed.  One of the new methods to control the disease is the use of plant essential oils. This study was aimed to evaluate the effect of Marjoram essential oil on the activity of bacteria causing citrus canker. Materials & Methods: In this experimental study, CBC- causing bacteria were isolated from infected Poldokhtar citrus gardens, and subsequently identified by phenotypic and biochemical tests, along with specific primers. The essential oil was extracted using a Clevenger extraction device. Antimicrobial effect of the essential oil was evaluated using disc diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the essential oil were investigated, as well. Then, the effect of different concentrations of marigold essential oil was studied. Following Marjoram essential oil preparation, it was injected into a Gas-Chromatography Mass-Spectrometry (GC-MS) to determine the composition. Results: MIC and MBC of essential oil were observed as 3.5 µl/ml, and 4 µl/ml, respectively. The most effective concentration for disease prevention on cut leaves were 4 µl/ml , and 4.5 µl/ml, which reduced disease incidence by 62.5% and 53.12 % on water agar test, and trays method. Conclusion: It is concluded that marjoram essential oil can be used as a potential compound to control citrus bacterial canker disease.