Isolation, screening
and characterization of bacteria from Rhizosphere soil of root crops for different
plant growth promotion (PGP) activities: an in vitro study
Konda Lakshmi Jahnavi, Sai Jaya Sri I. and Srilekha V.
Res. J. Biotech.; Vol. 21(1); 21-27;
doi: https://doi.org/10.25303/211rjbt021027; (2026)
Abstract
The use of plant growth-promoting rhizobacteria (PGPR) to enhance productivity may
serve as a viable alternative to organic fertilizers. The primary objective is to
mitigate pollution and conserve the environment through ecological agricultural
principles. Plant growth-promoting rhizobacteria (PGPR) influence plant growth through
various direct and indirect mechanisms. The bacteria inhabiting the plant's rhizosphere
are referred to as plant growth-promoting rhizobacteria (PGPR). PGPR bacteria are
free-living microorganisms that colonize plant roots and enhance plant growth. This
study aimed to identify and select the most effective PGPR and assess their efficacy
in zinc solubilisation, HCN generation and ACC deaminase activity.
This research assessed 19 isolates from several root crop fields for their plant
growth-promoting characteristics. The detected bacterial strains, especially the
KJ02 isolate, exhibit favourable PGPR traits, rendering them suitable for biofertilizer
production to enhance zinc availability in soil, thereby promoting the growth and
development of root crops. KJ02, derived from the rhizosphere soil of roots, can
be employed in soils deficient in zinc or where insoluble zinc is abundant. In this
investigation, three isolates showed positive results in the HCN synthesis assay,
evidenced by a colour change from yellow to dark brown, with KJ02 displaying the
most significant colour shift.
