Vegetos
(An International Journal of Plant Research & Biotechnology)
(eISSN: 2229-4473)
Impact of Bacillus velezensis OEE1 treatment against Verticillium wilt disease in expression level of chitinase, phospholipase and WRKY in olive trees
*Article not assigned to an issue yet
Cheffi Manel, Sellem Imen, Gharbi Yaakoub, Ennouri Karim, Mallouli Lotfi, Triki Mohamed Ali
Research Articles | Published: 27 August, 2026
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Keywords: Chitinase, Phospholipase D, WRKY, Transcription factors, qPCR
Abstract
Olive is one of the most popular plants around the world which is threatened by Verticillium wilt disease (VWO), caused by Verticillium dahliae. In this study, olive trees cv Chemlali were artificially inoculated with V. dahliae to evaluate expression of related genes promoting defense to VWO disease after several treatments with Bacillus velezensis strain OEE1 under greenhouse conditions. Total RNA was extracted and the first-strand cDNA was then synthesized. Expression level of chitinase, phospholipase D (PLD) and WRKY transcription factors genes were investigated using quantitative polymerase chain reaction (qPCR). The transcriptional level of these genes was up expressed in B. velezensis treated plants. Analyses revealed that preventive and curative treatments against V. dahliae involve modulation of chitinase and WRKY genes expression. The highest level of expression was observed at 3 days post inoculation. This expression was confirmed by the phenotypic symptoms of VWO disease that appeared in inoculated and treated olive trees.
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Author Information
Laboratory of Genetic Resources of Olive Tree: Characterization, Valorization and Phytosanitary Protection, Olive Tree Institute, University of Sfax, Sfax, Tunisia