Abstract
Abstract
Background
Date palm ((Phoenix doctylifera L.) suffers from several fungal diseases. The endophytic microorganisms present in higher plants generally offer protection to their host plants against invading phytopathogenic fungi and bacteria. In the present study, endophytic bacteria associated with date palm leaves were isolated and their in vitro antagonistic potential against fungal pathogens causing leaf spots in date palm was demonstrated.
Results
Endophytic bacteria were isolated from date palm leaves of 3 different cultivars viz., Nighal, Khalas and Khinaizi and evaluated for their inhibitory activity against leaf spot pathogens of date palm viz., Fusarium solani, Alternaria sp., Nigrospora sp., Thieloviopsis sp., Curvularia subpapendrofii and Tilletiopsis minor using an in vitro dual culture assay. Of the 24 endophytic bacterial strains tested, the endophytes designated B1, B7, B8 and B9 obtained from cv. Nighal showed inhibitory activities (more than 55% mycelial growth inhibition) against F. solani and Alternaria sp. None of the bacterial endophytes inhibited the growth of other fungal pathogens tested. These antagonistic bacterial strains were identified as Pantoea septica on the basis of 16S rRNA gene sequence analysis. The hyphae of F. solani and Alternaria sp. exhibited morphological abnormalities such as shrinkage and disintegration when grown in the presence of antagonistic bacterial endophytes. The cell-free culture filtrates of the bacterial endophytes caused inhibition of mycelial growth and induced leakage of electrolytes from the mycelia of F. solani and Alternaria sp. This is the first study that describes inhibition of the date palm pathogens F. solani and Alternaria sp. by P. septica.
Conclusion
Endophytic Pantoea septica strains isolated from date palm leaves inhibited the mycelial growth of F. solani and Alternaria sp. and induced morphological changes in their mycelia. The culture filtrates of these bacterial strains also inhibited the mycelial growth and caused leakage of electrolytes from the mycelia of F. solani and Alternaria sp. These promising bacterial strains can be exploited as biocontrol agents to control F. solani and Alternaria sp.-induced leaf spot diseases of date palm.
Publisher
Springer Science and Business Media LLC
Subject
Insect Science,Plant Science,Agronomy and Crop Science,Ecology
Reference37 articles.
1. Al-Badri BAS, Al-Maawali SS, Al-Balushi ZM, Al-Mahmooli IH, Al-Sadi AM, Velazhahan R (2020) Cyanide degradation and antagonistic potential of endophytic Bacillus subtilis strain BEB1 from Bougainvillea spectabilis Willd. Front Life Sci 13:92–98
2. Al-Hussini HS, Al-Rawahi AY, Al-Marhoon AA, Al-Abri SA, Al-Mahmooli IH, Al-Sadi AM, Velazhahan R (2019) Biological control of damping-off of tomato caused by Pythium aphanidermatum by using native antagonistic rhizobacteria isolated from Omani soil. J Plant Pathol 101(2):315–322. https://doi.org/10.1007/s42161-018-0184-x
3. Al-Nadabi H, Maharachchikumbura SS, Al-Gahaffi ZS, Al-Hasani AS, Velazhahan R, Al-Sadi AM (2020) Molecular identification of fungal pathogens associated with leaf spot disease of date palms (Phoenix dactylifera). All Life 13(1):587–597. https://doi.org/10.1080/26895293.2020.1835740
4. Al-Nadabi HH, Maharachchikumbura SSN, Agrama H, Al-Azri M, Nasehi A, Al-Sadi AM (2018) Molecular characterization and pathogenicity of Alternaria species on wheat and date palms in Oman. Eur J Plant Pathol 152(3):577–588. https://doi.org/10.1007/s10658-018-1550-4
5. Ben Mefteh F, Daoud A, Chenari Bouket A, Thissera B, Kadri Y, Cherif-Silini H, Eshelli M, Alenezi FN, Vallat A, Oszako T, Kadri A (2018) Date palm trees root-derived endophytes as fungal cell factories for diverse bioactive metabolites. Int J Mol Sci 19(7):1986. https://doi.org/10.3390/ijms19071986
Cited by
7 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献