Effect of Klebsiella oxytoca Bacteria on the Growth of Fungi Contaminating Date Palm Tissue Culture Media (Phoenix dactylifera L.)

The study was conducted in the Fungi Laboratory, University of Kerbala / College of Agriculture, with the aim of molecularly identifying the bacteria Klebsiella Oxytoca and testing its efficiency in inhibiting the fungi contaminating palm samples in tissue culture, which are the fungi Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum, and Meyerozyma guilliermondii, and testing their effect on the contamination rate and growth parameters (number of branches, fresh weight, dry weight). The results of the PCR analysis showed that the isolate belongs to the bacteria K. Oxytoca with a matching percentage of (100%), as the bacterial isolate was registered in the National Center for Biotechnology Information (NCBI) under the accession code (PV022086.1). The results also showed the superiority of live cells in inhibiting fungal growth by a percentage of 92.60% for each of A. flavus, P. chrysogenum and M. guilliermondii. The filtrate for the sixth day at a concentration of 10% was also superior with a high inhibition percentage of 92.60% against the fungi A. flavus and P. chrysogenum, while the greatest effect of the filtrate on the third day was 75.92% on the fungus P. chrysogenum, compared to the control treatment, which reached 100%. The results also showed that adding the filtrate of the bacteria K. Oxytoca for the sixth day at concentrations of 5 and 10% on the tissue medium had a positive effect on all the studied traits, including the average number of branches, fresh weight and dry weight, which reached (20.67, 6.25 and 1.05 respectively) for the 10% concentration, while the contamination rate reached 0% for the two concentrations compared to the control treatment of 100%.