Microbes-Mediated Zinc Biofortification in Tomato Plants Under Ag and TiO2-NP Stress
摘要
The experimental study was contrived to isolate zinc solubilizing bacteria (ZSB) from industrial contaminated soil, and their influence on biofortification of Zinc (Zn) in tomato plant under Ag and TiO2-NPs stress. Morphologically different bacterial colonies were selected from different agar medium and screened for their Zn solubilization potential and in vitro plant probiotic traits. Qualitative analysis was carried out on minimal medium supplemented with 0.1% zinc species. Biochemical characteristics of the selected ZSBs and identified by 16rDNA sequencing. Competence of Two selected ZSBs on soil Zn availability, Zn uptake and translocation in tomato plant were studied using pots amended with 20 mg kg− 1 Zinc oxide nanoparticles (ZnO-NPs) under silver (Ag) and titanium oxide nanoparticles (TiO2-NPs) stress (50, 100, 200, and 400 mg kg− 1). Biochemical characteristics and 16 S rRNA gene sequencing identified isolates as Bacillus sp. (OR497753) and Pseudomonas aeruginosa (OR497752). Available Zn in soil, Zn uptake and assimilation in plants and vegetative growth, photosynthetic pigments and oxidative stress were measured under Ag and TiO2-NPs stress, with and without ZSBs supplementation. Lower concentrations of the two NPs acted as a growth stimulant, but higher doses induced changes in the total soluble protein (73–112%), ROS generation (was not observed up to 118 mg kg− 1 Zn assimilation in leaves), lipid peroxidation and catalase (CAT) activity. Isolated ZSBs acted as potent agents in combination with economically viable zinc sources like ZnO-NPs, to facilitate zinc biofortification under stress conditions for sustainable agricultural practices.