Bacillus velezensis AR1 mediated plant nourishing through solubilization of hardly soluble phosphorus nutrient sources

Abstract

AbstractPhosphorus (P) plays a tremendous and determinant role in plant growth. However, its availability is hampered by the presence of metallic ions in soils. Therefore, the present work has been initiated to analyze the P-solubilization, organic acid, and phosphatase production potency of Bacillus velezensis AR1. Quantification of P-solubilization ranged from 150.6 to 491.3 and from 2.8 to 54.4 mg L−1 in the tricalcium phosphate (Ca-P) and aluminum phosphate (Al-P) medium, respectively. High-performance liquid chromatography analysis of organic acid detection showed variations, whereby 446.88 and 173.73 mg L−1 of succinic and 2-keto gluconic acids in the medium supplemented by Ca-P, and 12.59 and 11.83 mg L−1 of 2-keto gluconic and fumaric acids in the medium supplemented by Al-P were produced, respectively. There were also remarkable extracellular acid and alkaline phosphatase activities. Furthermore, inoculated and uninoculated 5- and 12-day-old culture broths of Ca-P and Al-P were applied to investigate their effect on pea plant growth. The result indicated that the highest plant height and tissue dry weight from the 5-day-old Al-P-modified culture (Al-5), and the highest root length from the 12-day-old Al-P-modified culture (AL-12) were recorded due to the solubilized phosphorus in the culture broth, even compared to the standard fertilizer. Similarly, the highest total nitrogen and total phosphorus were recorded due to Ca-P12 and Ck, respectively. These results concluded that the bacteria isolate B. velezensis AR1 could be developed into a bioinoculant for phosphate solubilization.

Keywords

• Bacillus velezensis
• bacteria culture broth
• organic acid
• phosphatase
• phosphorus solubilization
• Pisum sativum