ISOLATION AND CHARACTERIZATION OF ENDOPHYTIC ACTINOMYCETES ASSOCIATED WITH THYMUS SATUROIDES AND LAVANDULA MULTIFIDA GROWN IN BENI-MELLAL REGION IN MOROCCO
Authors:   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco., El Moukhtari Ahmed , Ziati Irouane ,   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco., Lamsaadi Nadia ,   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco., Mouradi Mohammed ,   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco., Farissi Mohamed ,   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco., El Hassni Majida ,   Laboratory of Biotechnology and Sustainable Development of Natural Resources (B2DRN), Polydisciplinary Faculty of Beni-Mellal, Sultan MoulaySlimane University, Mghila, PO Box. 592, Beni-Mellal 23000, Morocco.
Published: April 2024

ABSTRACT The present study aims to isolate endophytic actinomycetes (EPM) that are able to tolerate abiotic stresses, solubilize tricalcium phosphate (TCP) and produce indole-3-acetic acid (IAA), amylase and cellulose activities, while exhibiting high antagonistic activity against Fusarium oxysporum. f. sp. albedinis. Endophytic actinomycetes were isolated from roots, stems and leaves of Thymus saturoides and Lavandula multifida plant grown in Beni Mellal region, Morocco. According to the macro- and micro-morphological characteristics, a total of eleven EPM isolates were isolated and purified. Results indicated that the majority of isolates were able to tolerate pH and salt stresses. Moreover, the majority of the isolates were able to solubilize TCP on Pikovskaya (PVK)-agar medium which ranged from 25% to 458%. Additionally, on PVK-liquid medium, soluble phosphate content varied from 163.81 µg/mL recorded for the isolate LRP1 to 730 µg/mL observed for the isolate TSRP2. For IAA production, the amount produced varied from 1.70 µg/mL recorded for the isolate LRP1 to 14.13 µg/mL recorded for both LTP2’ and TSRP2. Endophytic actinomycetes isolated in this work also showed a remarkable capacity to degrade some compounds such as cellulose and starch. In addition, some of them showed a strong inhibitory activity against the fungus F. albedinis with a percentage of inhibition ranged from 69.13% observed for LTP2’ to 86.6% recorded for the isolate LRP2. Results from this study indicate that the two isolates LTP2’ and TSRP2 were the most efficient and that actinomycetes could be used in biocontrol against the fungus F. albedinis.