In Vitro Biocontrol Potential of Endophytic Methylobacterium sp. Against Plant Pests Pseudomonas savastanoi and Botrytis sp.

Authors

  • Chihani Abdelghani Festetics Doctoral School, Institute of Agronomy, Georgikon Campus, Hungarian University of Agriculture and Life Sciences, 8360 Keszthely, Hungary
  • Nawal Selami Laboratory of Productions, Vegetal and Microbial Valorizations (LP2VM), University of Science and Technology- Mohamed BOUDIAF- (USTO M.B) BP. 1505 El M’naouer 31000, Oran, Algeria.

DOI:

https://doi.org/10.70809/7353

Keywords:

Methylobacterium sp, Pseudomonas savastanoi, Botrytis sp, olive, biological control

Abstract

Fungi and pathogenic bacteria cause numerous plant diseases that significantly affect crop productivity. The use of biological control agents represents an environmentally friendly alternative to chemical pesticides. The present study aimed to evaluate the in vitro antagonistic effects of Methylobacterium sp. against Pseudomonas savastanoi and Botrytis sp., two major phytopathogens affecting olive (Olea europaea L.) and faba bean (Vicia faba L.), respectively.The bacterial strain Methylobacterium sp., isolated from nodules of Retama monosperma, was tested for its antibacterial activity against P. savastanoi using the direct method of Fleming et al. (1975) and the indirect method of Barefoot and Klaenhammer (1983). The antifungal potential against Botrytis sp. was assessed by the direct confrontation technique on Mueller-Hinton agar medium. The results revealed that no inhibition was observed with the direct method, whereas the indirect method showed a clear inhibitory zone of approximately 5 mm against P. savastanoi, indicating that the inhibitory metabolites are mainly intracellular. The confrontation test demonstrated a significant reduction in Botrytis sp. mycelial growth; with an inhibition rate exceeding 38%. These findings highlight the potential of Methylobacterium sp. as a promising biological control agent against bacterial and fungal phytopathogens. Further studies under in vivo conditions are required to confirm its efficacy and identify the active metabolites involved in the antagonistic activity.

Author Biography

  • Chihani Abdelghani, Festetics Doctoral School, Institute of Agronomy, Georgikon Campus, Hungarian University of Agriculture and Life Sciences, 8360 Keszthely, Hungary

    corresponding author
    Chihani.Abdelghani.2@phd.uni-mate.hu


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Published

2025-12-17

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How to Cite

Abdelghani, C., & Selami, N. (2025). In Vitro Biocontrol Potential of Endophytic Methylobacterium sp. Against Plant Pests Pseudomonas savastanoi and Botrytis sp. GEORGIKON FOR AGRICULTURE, 29(1), 9-15. https://doi.org/10.70809/7353