EVALUATION OF PLANT GROWTH HORMONES (IAA AND GA3) AND ANTIBIOTIC PRODUCTION POTENTIAL OF SOIL MICROBES

Himani Hedaoo*, Dharmendra Singh, Divakaran Pandiyan and Saurabh Kashyap

ABSTRACT

Diverse bacterial species possess the ability to produce the auxinphytohormone indole-3-acetic acid (IAA). Reviewing the role of bacterial IAA in different microorganism–plant interactions highlights the fact that bacteria use this phytohormone to interact with plants as part of their colonization strategy, including phytostimulation and circumvention of basal plant defense mechanisms. Antibiotics play a key role in the suppression of various soilborne plant pathogens by antagonistic microorganisms. Several abiotic factors such as oxygen, temperature, specific carbon and nitrogen sources, and microelements have been identified to influence antibiotic production by bacteria biocontrol agents. Among the biotic factors that may play a determinative role in antibiotic production are the plant host, the pathogen, the indigenous microflora, and the cell density of the producing strain. The aim of the present investigation is determine the fertility potential of soil microbes with the reference of plant growth hormones production and antibiotic production.

Keywords: Soil microbes, plant growth hormones, Antibiotics, PGPR, auxin IAA.