title: Selenium-fortified wheat: potential of microbes for biofortification of selenium and other essential nutrients.
abstract: Selenium (Se) is an essential micronutrient for humans and animals, and Se deficiency is a worldwide problem. Plants are a main dietary source of Se for humans and livestock. In this study we investigated the effect of two selenium-tolerant bacterial strains Bacillus cereus-YAP6 and Bacillus licheniformis-YAP7, on the growth and Se uptake by wheat plants. The bacteria-inoculated plants exhibited a significant increase in spike length, shoot length and dry biomass. Inoculated Se-treated plants also showed increased stem Se, S, Ca and Fe concentrations, by up to 375%, 40%, 55%, and 104%, respectively, and increased kernel Se, S, Ca and Fe concentrations by up to 154%, 85%, 60%, and 240%, respectively, compared to un-inoculated Se-treated plants. In conclusion, inoculation with strains YAP6 andYAP7 is a good Se biofortification strategy for wheat. Both strains showed resistance to other toxic elements, i.e., As, Cd, Co, Cr, Cu, Mn and Zn. Optimal growth temperature and pH for both strains were 37°C and pH7, respectively, but both strains can grow very well at different temperatures (28-45°C) and at alkaline pH. Both strains have high Se reduction potential: strains YAP6 and YAP7 converted 92% and 32% of selenite into elemental Se within 48 h, respectively.
authors.affiliation: a Department of Microbiology and Molecular Genetics , University of the Punjab, Quaid-e-Azam Campus , Lahore , Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Yasin
authors.forename: Ali Farag
authors.initials: AF
authors.lastname: El-Mehdawi
authors.forename: Elizabeth A H
authors.initials: EA
authors.lastname: Pilon-Smits
authors.forename: Muhammad
authors.initials: M
authors.lastname: Faisal
mesh_terms: D001407:Bacillus / Q000502:physiology*; D001409:Bacillus cereus / Q000502:physiology; D001673:Biodegradation, Environmental; D006863:Hydrogen-Ion Concentration; D012643:Selenium / Q000737:chemistry*; D013696:Temperature; D014131:Trace Elements; D014908:Triticum / Q000254:growth & development* / Q000378:metabolism* / Q000382:microbiology
chemical_list: D014131:Trace Elements; D012643:Selenium
keywords: Bacillus; ICP-AES; metals; plant-microbe interaction; selenium