Bacteria Isolated from Ricinus communis and Its Possible Application in Agroecology

Abstract

Ricinus communis is a plant that is characterized by its different applications, in addition to being a wild plant favors its inclusion in agroecological practices because it does not represent high costs for producers. the aim of the work was to evaluate the bacterial isolates of R. communis with respect to its inhibitory activity, chitinolytic, DNase, solubilization of phosphate, biofilm formation and growth promoting effect in Allium sativum and Medicago sativa. The collection of R. communis leaves was carried, which were washed and disinfected with sodium hypochlorite solution in order to isolate bacteria in nutritive agar. The isolates obtained were identified by PCR amplification with the oligonucleotides RM and RB and the amplified products were sequenced for identification. The following tests were carried out on each of the isolates: growth inhibition vs Fusarium oxysporum, chitinolytic activity, DNase, solubilization of phosphate, biofilm formation and growth evaluation in A. sativum and M. sativa. Ten isolates were obtained that were identified as Pseudomonas 50%, Enterobacter 30% and Bacillus 20%. Growth inhibition evaluations against F. oxysporum showed that Bacillus showed significant inhibitory activity. The total isolates were negative for chitinolytic activity, 50% were positive for DNase, 40% positive for solubilization of phosphate and for biofilm formation 25% promoted weak formation and 10% moderate. Both plant models showed an increase in the biomass of fresh weight and dry weight of their roots when they were inoculated with the bacterial consortium at 50%, 75% and 100%.