Plant-growth-promoting Bacillus and Paenibacillus species improve the nutritional status of Triticum aestivum L.

Wheat is one of the best-domesticated cereal crops and one of the vital sources of nutrition for humans. An investigation was undertaken to reveal the potential of novel bio-inoculants enriching micronutrients in shoot and grains of wheat crop to eliminate the hazards of malnutrition. Sole as well as consortia inoculation of bio-inoculants significantly enhanced mineral nutrients including zinc (Zn) and iron (Fe) concentrations in shoot and grains of wheat. Various treatments of bio-inoculants increase Zn and Fe content up to 1-15% and 3-13%, respectively. Sole inoculation of Bacillus aryabhattai (S10) impressively improves the nutritious of wheat. However, the maximum increase in minerals contents of wheat was recorded by consortia inoculation of Paenibacillus polymyxa ZM27, Bacillus subtilis ZM63 and Bacillus aryabhattai S10. This treatment also showed a maximum bacterial population (18 × 104 cfu mL-1) in the rhizosphere. The consortium application of these strains showed up to a 17% increase in yield. It is evident from the results that the consortium application was more effective than sole and co-inoculation. A healthy positive correlation was found between growth, yield, and the accessibility of micronutrients to wheat crops at the harvesting stage. The present investigations revealed the significance of novel bacterial strains in improving the nutritional status of wheat crops. These strains could be used as bio-inoculants for the biofortification of wheat to combat hidden hunger in developing countries.