Qualitative in vitro Evaluation of Plant Growth Promoting Activity of Electrogenic Bacteria from Biohydrogen Producing Microbial Electrolysis Cell towards Biofertilizer Application

C.Nagendranatha Reddy; K. Arunasri; Dileep Kumar Yeruva; K.Vamshi Krishna; S.Venkata Mohan

Authors

C.Nagendranatha Reddy Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad-500 007, India
K. Arunasri Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad-500 007, India
Dileep Kumar Yeruva Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad-500 007, India
K.Vamshi Krishna Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad-500 007, India
S.Venkata Mohan Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad-500 007, India

Keywords:

Biofertilizer, Bacterial Isolates, Siderophores, Indole Acetic Acid, Antifungal Activity

Abstract

DBio-fertilizers confer a sustainable alternate to chemical fertilizers through their plant growth promoting activities and contribute significantly to enhance soil fertility and crop yields. The present study identifies five bacterial strains (K7, K8, K9, K11 and K18) isolated from a different microbiome (Microbial Electrolysis Cell; MEC) to have nitrogen fixing capability. Consequently, the isolates were identified by 16S ribosomal RNA gene sequencing analysis as Bacillus safensis strain K7, B. nealsonii strain K8, B. nealsonii strain K9, Leifsonia shinshuensis strain K11 and Streptomyces griseoviridis strain K18. Since the isolates exhibited nitrogen fixation property which is one of the important characteristics of plant growth promoting activity, these strains were further evaluated for other biofertilizer properties viz. phosphate solubilization, indole acetic acid (IAA) production, siderophores activity and anti-fungal activity. The results showed that siderophore activity was observed in both K7 and K18 strains while IAA production and antifungal activity was observed in K7 and K18 strains respectively. Phosphate solubilization was observed only in K9. The results illustrate that Streptomyces griseoviridis strain K18, Bacillus safensis strain K7 and B. nealsonii strain K9 hold promise to be used as a biofertilizer with potential plant growth promoting activity.