Forms of phosphorus and its bioavailability in rice grown in an alluvial soil treated with rock phosphate enriched compost

Abstract

Lower utilization efficiency of phosphorus (P) in soils is a major setback for the agricultural sector. The objective of this study was to investigate the effect of compost enriched with Rock phosphate on fractions of P in soil and how these forms affect the bioavailability of P in Rice. P fertilization was performed with the enriched compost and compared with rock phosphate and a conventional P fertilizer i.e. single superphosphate (SSP). We conducted a field experiment at Bihar Agricultural University, Sabour with Rice as the test crop in a randomized block design. Chemical P fractions were estimated through sequential fractionation and biomass production and P concentrations in plant parts were measured to estimate the plant P uptake. Yield, yield attributing parameters and P uptake in straw and grain were observed to be affected significantly by the addition of P enriched compost along with 50% recommended dose for P with the total recommended dose for N and K, when compared to absolute control. The alkaline nature of experimental soil seemingly improves the solubility of P from various fractions and the use efficiency of rice, which favors P uptake which was evidently the factors that contributed to these results. The percentage contributions of different fractions to the total P content in soil after paddy harvest were observed to be in the order: Labile-P < Fe/Al-P < Ca-P < residual P. Combined application of P enriched compost and inorganics sustained crop yield and enhanced P uptake in Rice when compared with sole application of chemical fertilizers.

Keywords:

• bioavailability
• enriched compost
• fractions
• phosphorus
• rice

Acknowledgments

The authors are grateful to the administration and technicians of Bihar Agricultural University, India, for providing experimental area and laboratory facilities for the conduction of the research work.

Disclosure statement

The authors declare that they have no conflicts of interests.