Some Characteristics of a Plant Growth Promoting <i>Enterobacter</i> sp. Isolated from the Roots of Maize

Abstract

Some properties of an Enterobacter sp. isolated from the roots of maize are described. Isolation was carried out using the semisolid enrichment culture technique and subsequent plating, both on nitrogen free biotin medium. Morphological, biochemical and phylogenetic characterization using the MicroSeq  16S rDNA technique were employed in identification of isolate, which was revealed to be closest matched at 99.4% with Enterobacter asburiae. The isolate possessed properties of plant growth promoting bacteria. Thus, it produced indole-3-acetic, plant polymer hydrolyzing enzymes, pectinase and cellulase as well as ammonia in vitro. The isolate grew well in the presence of both 3% NaCl and 10 µg of streptomycin. In plate bioassays, isolate promoted the germination of both maize and rice seeds as well as root and lateral root growth resulting in weight increases of seedlings over their controls. Experiments to quantify ability of isolate to promote plant growth was performed using hydroponics solutions and as appropriate, an inoculum of the isolate. Pot experiments were also employed. Results from these studies showed that isolate enhanced nitrogen accumulation and significantly (P < 0.05), improved the growth of maze seedlings over controls. Isolate has potential for utilizetion as inocula for sustainable production of cereals.

Klebsiella pneumoniae VRE36 as a PGPR isolated from Saccharum officinarum cultivar Co99004

“…Islam et al [18] reported the phosphate solubilization index of the rice isolates varied from 1.2 to 6.7. Many species of rhizobacteria including Bacilli, Pseudomonas and Klebsiella can solubilise insoluble phosphates in the agar assay in vitro [19][20]. Quantitative estimation in NBRIP broth reveals 17.4±1.78µg/ml solubilised P (Table 1).…”

Evaluation of Bacteria Isolated from Olive Mill Wastewater as Plant Growth Promoter on Basil (Ocimum basilicum L.) plant

“…Aspartic, glutamic acid and glycine were the greatest components (425.4, 354.78 and 401.44). Ogbo and Okonkwo (2012) found that the production of ammonia is frequently reported for PGPR, a process most probably resulting from the deamination (ammonification) of amino acids present in the peptone used for this assay. It has been suggested that ammonia may have a role in antagonism against competing flora, particularly the fungi.…”

“…asburiae + half dose of N2 gave high ratio of N2 compared with control in the second cut (0.895%). Ogbo and Okonkwo (2012) reported that the higher concentration of nitrogen in maize seedlings treated with inoculums by Enterobacter sp. compared with those grown without it inoculation.…”

Physiological and biochemical characterization ofAzospirillum brasilensestrains commonly used as plant growth-promoting rhizobacteria

“…This differential medium has the same composition than Nfb medium but, instead of BTB, Congo red dye was used to increase selectivity for identifying the Azospirillum genus . However, some authors used the RC medium for Azospirillum isolation and they found out typical scarlet red colonies which were identify as Pseudomonas , Bacillus , Streptococcus , and Enterobacter genera .…”

“…Different letters in superscript indicate significant differences in the average absorbance values between strains for each CS, using the Tukey's test (p 0.05). were identify as Pseudomonas, Bacillus, Streptococcus, and Enterobacter genera [29,31,32,33].…”