Co-Inoculation Effect of Rhizobia with Potassium and Zinc Solubilizing Bacteria for Enhancing Some Growth Parameters of Phaseolus vulgaris Plants
Year: 2021
Type: article
Abstract: Four strains of Rhizobium leguminosarum bv.Phaseoli (301, 3612, 1799 and 3629), Bacillus megaterium, Bacillus polymyxa and Azotobacter chroococcum were evaluated for potassium, Zinc solubilization and exopolysaccarides production.The maximum potassium (K) liberated was recorded by Bacillus megaterium (33.2 μg/ml) followed by Bacillus polymyxa (32.4 μg/ml) and Azotobacter chroococcum (32.0 μg/ml).Azotobacter chroococcum showed the highest remarkable solubilization potential for zinc oxide (275) and was the highest in terms of EPS (7.44 g/L).Rhizobium leguminosarum bv.Phaseoli (301) showed K-liberated (10μg/ml), Zinc solubilization efficiency was (100) and EPS production was (6.36 g/L).Upon these tests Bacillus megaterium, Azotobacter chroococcum and Rhizobium leguminosarum bv.Phaseoli (301) were selected and tested for efficient K solubilization using various potassium sources and during different periods of incubation (5, 10 and 15 days).The highest levels of K solubilization were observed in KCl and K2SO4 amended medium broth compared to mica powder-containing media.The maximum release of potassium were 40, 120 and 190 μg/ml (untabulated) in R. leguminosarm bv phaseoli (301), Azotobacter chroococcum and Bacillus megaterium respectively at 15 days of incubation.A pot experiment was carried out to study the effect of coinoculation of rhizobial strain with K and Zn solubilizing bacteria and the results showed that the application of T7 of Rhizobium sp.strain 301+Azotobacter chroococcum (that enhanced for Ksolubilization) exhibited the best results of vegetative growth parameters, chlorophyll contents and increased nitrogen, phosphorus, potassium and zinc contents in phaseolus vulgaris plants comparing the controls.
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W4312329041