Isolation, Characterization and Herbicidal Activity of Pseudomonas fluorescens for Controlling Some Wheat Weeds
Keywords:
Zucchini squash, DAS-ELISA, phylogenetic analyses, wild gourdAbstract
Pseudomonas spp was isolated from the rhizosphere area of two wild plants Radish Raphanus raphanistrum and barley Hordeum spontaneum naturally grown in a wheat Triticum aestivum field. The inhibitory activity of this bacterium was tested against the germination of weed seeds. Six isolates of Pseudomonas sp. were recovered from symptomatic weed plants exhibiting stunting and yellowing that collected from different locations at Baghdad Province. The isolates of Pseudomonas spp varied in their inhibitory activity against seed germination of wild radish and barley, scoring (8.75-92.5) and (10.00-96.25), respectively. The isolates PR4 and PR6 maximum inhibition rates on wild radish and barley ranged (82.50-92.50) and (90.00-96.25), respectively. Whilst, bacterial filtrates when applied could inhibit the seed germination of the two weeds scoring (6.25-90.00) and (5.00-93.75), respectively. Amongst other isolates, filtrates from PR4 and PR6 scored the highest inhibition rates in the seed germination of wild radish and barley which ranged (85.00-90.00) and (88.75-93.75) respectively. Based on morphology and molecular identification PR6 and PR4 were bacterial isolates of Pseudomonas fluorescens. Nucleotide sequences of the two isolates were deposit in the NBCI GenBank data base under the accession numbers MW740144 and MW740145. Data indicated the application of bacteria and their filtrates enabled an ecofriendly control against weeds.
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