Indole 3-Acetic Acid Production by Aspergillus Species Isolated From Chilli Rhizospheres

In the present study soil samples were collected from different chilli rhizospheres in the vicinity of Guntur, Andhra Pradesh, India and the filed trails were conducted in the year of 2018-2019. A total of 57 microbial strains were isolated from chilli rhizosphere. All the strains were isolated from potato dextrose agar media by using 10-4 serial dilutions. Fine and clear colonies were picked and transformed into a culture tubes for further studies. For the preliminary screening there are 10 isolates were considered as fungal strains based on spore morphology. The spores are round and irregular in shape with green to light brown in colour. Preliminary identification of these fungal isolates was based on morphological and cultural characters on potato dextrose agar medium. All ten strains showed the maximum indole acetic acid production on Czepakdox agar medium. Various optimization studies like incubation period, pH, temperature and carbon and nitrogen sources were studied by affecting the indole acetic acid productions i.e., 10 days incubation period, pH 7.0 and 30 C. Carbon and nitrogen sources are also affected the indole acetic acid production in this optimization. A carbon and nitrogen source in the optimal medium plays a major role for the production indole acetic acid. Among them, the strain Aspergillus PB-7 in presence of Glucose and peptone showed the maximum IAA production of 110pg/m1 and 75pg/ml. Successful inoculation of agricultural crops with biocontrol plant growth promoters includes the delivery of sufficient inoculum to the target, economical production of large quantities of microorganisms. Rhizospheric microbes especially plant growth promoting microorganism were promising to be developed as multifunctional biofertilizer.