Zinc solubilizing Bacillus spp. potential candidates for biofortification in maize.

Abstract

Bioaugmentation of Zn solubilizing rhizobacteria could be a sustainable intervention to increase bioavailability of Zn in soil which can be helpful in mitigation of yield loss and malnutrition of zinc. In present study, a number of pure rhizobacterial colonies were isolated from maize rhizosphere and screened for their ability to solubilize zinc oxide. These isolates were screened on the basis of zinc and phosphate solubilization, IAA production, protease production, catalase activity and starch hydrolysis. All the selected isolates were also positive for oxidase activity (except ZM22), HCN production (except ZM27) and utilization of citrate. More than 70% of isolates produces ammonia, hydrogen cyanide, siderophores, exopolysaccharides and cellulase. More than half of isolates also showed potential for urease activity and production of lipase. The ZM31 and S10 were the only isolates which showed the chitinase activity. All these isolates were evaluated in a jar trial for their ability to promote growth of maize under axenic conditions. Results revealed that inoculation of selected zinc solubilizing rhizobacterial isolates improved the growth of maize. In comparison, isolates ZM20, ZM31, ZM63 and S10 were best compared to other tested isolates in stimulating the growth attributes of maize like shoot length, root length, plant fresh and dry biomass. These strains were identified as Bacillus sp. (ZM20), Bacillus aryabhattai (ZM31 and S10) and Bacillus subtilis (ZM63) through 16S rRNA sequencing. This study indicated that inoculation of Zn solubilizing strains have potential to promote growth and can be the potential bio-inoculants for biofortification of maize to overcome the problems of malnutrition.

• Authors: Muhammad Zahid Mumtaz, Maqshoof Ahmad, Moazzam Jamil, Tanveer Hussain
• Journal: Microbiological research (Microbiol Res) Vol. 202 Pg. 51-60 (Sep 2017) ISSN: 1618-0623 [Electronic] Germany
• PMID: 28647123 (Publication Type: Journal Article)
• Copyright: Copyright © 2017 Elsevier GmbH. All rights reserved.

Chemical References

• DNA, Bacterial
• RNA, Ribosomal, 16S
• Soil
• Phosphorus
• Zinc
• Zinc Oxide

Topics

• Axenic Culture
• Bacillus (enzymology, genetics, isolation & purification, metabolism)
• Biofortification
• Biomass
• DNA, Bacterial
• Phosphorus (chemistry)
• Phylogeny
• Plant Roots (growth & development, microbiology)
• RNA, Ribosomal, 16S (genetics)
• Rhizosphere
• Sequence Alignment
• Soil (chemistry)
• Soil Microbiology
• Solubility
• Zea mays (growth & development, microbiology)
• Zinc (chemistry)
• Zinc Oxide (chemistry)