Improvement of Phaseolus vulgaris growth by inoculation with multifunctional native rhizobacteria isolated from rhizospheric soils in Gaza strip- Palestine

Abstract

Overuse of chemical firtilizers is a global problem that had a negative impact on soil comosition and its microbial communities. The present study was conducted to isolate, identify plant growth promoting rhizobacteria (PGPR) associated with (Phaseolus vulgaris) in Gaza strip - Palestine and to determine bacterial inoculations/co-inoculations that can enhance plant growth. A total of 35 different morphological isolates were collected and examined for plant growth. Five isolates that were tentatively promising (in plant growth promoting traits i.e. IAA production, Zn solubilization, ACC deaminase activity and phytase production) , were selected and subjected to partial 16S rDNA gene sequencing. The five isolates were: Bacillus proteolyticus MK123398, Bacillus wiedmannii MK123399, Pseudomonas plecoglossicida MK123400, Pseudomonas cedrina MK123401 and Bacillus xiamenensis MK123402. Results indicated that some bacterial combinations significantly increased plant growth, but no significant increase of total nitrogen concentration was observed. Consortia of (B. proteolyticus + B. xiamenensis),  (P. plecoglossicida + P. cedrina),  (B. proteolyticus +  B. wiedmannii  + B. xiamenensis), (B. proteolyticus + P. plecoglossicida + B. xiamenensis), B. wiedmannii ), and (B. wiedmannii  + P. plecoglossicida) showed significant increase in plant growth respectively. Those bacterial consortia have the potential for developing biofertilizers for integrated nutrient management strategies and decrease chemical firtilizers abuse stratiges.