Multifarious microbial biostimulants promote growth in Arachis hypogaea L.

Plant Growth Promoting Rhizobacteria (PGPR), a microbial biostimulant has been widely studied to stimulate plant growth through induction of natural biological processes. However, lack of successful validation under open field remains a barrier to mark their standard in agriculture. Therefore, the aim of the research was to highlight the potential of PGPR biostimulants via in vitro studies and subsequently to demonstrate the in planta evaluation in oilseed crop, Arachis hypogaea L. (Groundnut) under pot and field trials. The two rhizobacterial strain was identified as Pseudomonas fluorescens and Bacillus subtilis by 16s rRNA gene sequence analysis. Both the strains were functionally screened for plant growth promoting traits. Pot and field trials were conducted where seeds were inoculated with PGPR biostimulants and harvested at 30 and 90 days. Biostimulant treatments were applied as single and co-inoculation in groundnut and the growth factors, biochemical parameters, yield, and seed quality were analyzed. The study inferred that the consortium of PGPR biostimulants significantly (p < 0.05) showed highest growth, photosynthetic pigments, nodulation status, leghaemoglobin content, yield attributes, and also biofortification of seed nutrients in oilseed crop under both pot and field conditions than un-inoculated control. This study supports the idea of the application of PGPR as microbial biostimulants through successful open field trial to facilitate its implementation as a feasible and potential agricultural product to synthetic fertilizers thereby influencing sustainable and stable crop production.