Changes in Phosphorus Fractions Upon Inoculation of Pseudomonas sp. and Nano Phosphorus Application in Wheat Rhizosphere

ABSTRACT

The decreased availability of phosphorus (P) in Indian soils including the soils of Bihar can be attributed to its affinity to the formation of complex compounds. This study is undertaken to investigate the interactive effect of mineral P, nano P and phosphate-solubilizing bacteria (PSBs) for different inorganic and organic P fractions in an alluvial soil with seven treatments in triplicates viz. control (T1); 100% RDF (120:60:40 N:P:K) (T2); 100% recommended dose of P (RDP) through nano P as soil application (T3); 50% nano-P soil application + 50% nano P as foliar application at flowering stage (T4); 50% RDP + 25% P (nano P) soil application + PSB at the rate of 0.335 µl kg⁻¹ soil (T5); 50% RDP + 25% P (nano P) foliar spray + PSB at the rate of 0.335 µl kg⁻¹ soil (T6) and application of 100% P through FYM at the rate of 10.71 g kg⁻¹ + PSB at the rate of 0.335 µl kg⁻¹ soil (T7). The application of treatment T7 yielded highest soluble P, Al-P and Fe ₂ P while Fe ₁ P, Ca-P and residual P were found to be greatest in case of treatment T5. Soluble P fraction had established significant positive correlation with Fe₁-P (p ≤ .836), Ca-P (p ≤ .842) and Fe₂-P (p ≤ .822). Hence, the application of mineral P in combination with nano P as soil application and conjugative application of FYM along with PSB could be very helpful in increasing the availability of soluble P by increasing its release and availability under naturally P-deficient conditions.

KEYWORDS:

• Fractionation
• labile P
• nano P
• non-labile P
• phosphorus
• Pseudomonas

Acknowledgements

The study was supported by the Bihar Agricultural University, Sabour, Bihar, India. Authors are grateful to the Vice-Chancellor, Director of Research and Dean Post Graduate Studies, Bihar Agricultural University, Sabour, for their critical suggestions and support for carrying out this research.

Disclosure statement

No potential conflict of interest was reported by the author(s).