Antimicrobial
and Phytohormone production potential of Azotobacter chroococcum and its effect
on the growth of non-leguminous plants
Karale Mahesh, Karale Pushpa, Kadam Tukaram, Bhosale Hemlata and More Rahul
Res. J. Chem. Environ.; Vol. 28(6); 28-36;
doi: https://doi.org/10.25303/286rjce28036; (2024)
Abstract
The overuse of chemical fertilizers in agriculture leads to a decrease in the fertility
of soil and increases chemical pollution, which has adverse effects on living things.
Biofertilizers have a solution towards chemical fertilizer to improve soil fertility
and crop production. Therefore, the present study was undertaken to isolate different
isolates of Azotobacter sp. to identify effective isolates for plant growth promoting
activities and biological control. Six Azotobacter sp. were isolated and their plant
growth promoting activities were checked. The isolate AC3 produced the highest amount
(64 μg/ml) of IAA and produced HCN and 72 μg/ml of ammonia. The isolates AC1 and
AC4 lacked the HCN production. Isolate AC3 showed a 26 mm zone of clearance on Pikovaskys
agar, solublized the highest 71 μg/ml of inorganic phosphate and had the ability
to produce siderophores.
The isolate AC3 showed good antimicrobial potential against pathogens. Isolate AC3
was identified as Azotobacter chroococcum on the basis of morphological and biochemical
characteristics. The bioactive compound was produced by using Azotobacter chroococcum
and purified by column chromatography. Fraction 1 showed good antimicrobial activity
against all the pathogens. The highest zone of inhibition was 15 mm against F. oxysporum.
FT-IR analysis of fraction 1 revealed carboxylic acid, alkane and carbonyl functional
groups. Azotobacter chroococcum had a greater effect on the growth of non-leguminous
plants in the bacterially inoculated pot than in the control.
