Next-Generation Biofertilizers: Nanoparticle-Coated Plant Growth-Promoting Bacteria Biofertilizers for Enhancing Nutrient Uptake and Wheat Growth

Contemporary agricultural practices rely heavily on synthetic fertilizers to provide essential nutrients for crops, contributing to diminished soil fertility and environmental pollution. An innovative solution lies in the strategic combination of nanoparticles and biofertilizers, as a unique and environmentally friendly technology, enhancing soil enzyme activity and the availability of essential plant nutrients. The goal of this study was to show the efficacy of this technology and identify the best combination of nanoparticles and PGPB for plant growth promotion, nutrient uptake, and soil health. This study investigated the efficacy of nanobiofertilizers generated by combining two plant growth-promoting bacteria (PGPB), (<i>Bacillus</i> sp.) CP4 and AHP3, along with mesoporous silica nanoparticles (MS NPs), zinc oxide nanoparticles (ZnO NPs), and copper oxide nanoparticles (CuO NPs) in different combinations. A greenhouse study employing two wheat varieties, NABI MG11 (black wheat) and HD3086, was conducted. There were 15 treatments, including treatments consisting of only bacteria, treatments consisting of the combination of nanoparticles and nanobiofertilizers, and 1 control treatment, and each treatment had three replicates. In evaluating plant growth characteristics, the synergy between ZnO NPs and CP4 demonstrated the most favorable outcomes in terms of overall plant growth and various traits. Similarly, MS NPs, in conjunction with both PGPB, exhibited enhancements in plant growth traits, including fresh weight, chlorophyll content, proline levels, and nitrogen content. Over half of the combination treatments with nanoparticles and PGPB did not show a significant improvement in plant growth promotion traits and soil health when compared to nanoparticles alone. The findings of this study underscore the potential of nanobiofertilizers as an innovative and robust tool for promoting sustainable agriculture.