Enhancing wheat growth and nutrient content through integrated microbial and non-microbial biostimulants

This study focused on two aspects: to develop a selected functionally competent bacterial community, and its integrated with biostimulant humic acid and seaweed extract which was validated to enhance wheat growth and nutrient content. Wheat and maize-associated bacterial isolates (92) were screened for Plant Growth-Promoting traits (PGPts-72) and Community-Forming traits (CFts-66). 46 isolates possessed both kinds of traits, of which 20 isolates were chosen based on high Bonitur scale ratings. Based on metabolic diversity, growth rate, and compatibility, 11 isolates were grouped to make a synthetic microbial community (SM). Non-microbial biostimulants, humic acid (HA) and seaweed extract (SWE) were used, and 0.2% HA and 1% SWE were found to be optimal for bacterial and plant growth. SM integrated each with 0.2% HA and 1% SWE, leading to products SynBio1 (SM + HA) and SynBio2 (SM + SWE). Under microcosm study, SynBio1 and SynBio2 improved germination by 90.10% and 83.80%, respectively. SynBio1 increased chlorophyll content by 40.5 SPAD units, root length by 15.7%, and shoot length by 18.4%. Field level validations revealed that SynBio1 increased plant height by 15.76%, root length by 27.16%, and flag leaf length by 21.35% compared to the control. The grain yield with SynBio1 was 40.41% higher than that of the control. Macro and micronutrient analysis of seeds treated with SynBio1 showed significant improvements. These findings demonstrate the potential of integrating microbial communities with biostimulants, and they pave the way for developing novel bioinoculants for sustainable agriculture and promoting a healthier environment.