Combined effect of rock phosphate with single super phosphate on yield and phosphorus use efficiency under maize-groundnut cropping sequence in Alfisols of Odisha

Abstract

Aim: The present study was conducted to investigate the effect of combined application of rock phosphate with water soluble phosphorus fertilizers on its efficiency in relation to soil and crop production. Methodology: Rock phosphate and single super phosphate were used as supplemental source of phosphorus and applied in variable combinations at graded doses, with maize and groundnut as test crop. Lime was applied in combination with 100% SSP to analyse its effect. The composite surface (0-15 cm) soil samples were collected at critical growth stages of maize and groundnut and further analyzed for different physical and physico-chemical characteristics. The plant samples were collected from each treatment at harvest stage for nutrient analyses. Results: Application of rock Phosphate increased the available phosphorus in soil. The combined treatment significantly influenced the yield attributes and nutrient uptake of both maize and groundnut crops. Among the combination, equal proportion of soluble single super phosphate and insoluble rock phosphate source of P outreached the other combination ratios. The highest agronomic phosphorus use efficiency and relative agronomic efficiency of the cropping sequence was obtained with the combined treatment of Single super phosphate along with lime. Interpretation: Combination of rock phosphate which has been reported to be farmer’s pocket friendly along with single super phosphate under acid soil conditions holds the potential to produce better results as compared to use of lone conventional water soluble phosphatic fertilizer like single super phosphate.

Rock Phosphate and Biochar Effects on Greenhouse Gas Emissions and Soil Fertility in Southern Alberta Potato Field

“…Rock phosphate has a greater potential to improve soil health than triple super phosphate. Rock phosphate releases P slowly to the soil for plant uptake unlike triple super phosphate that appeared fixed in the soil (Sarkar et al, 2018;Sarangi et al, 2020;Mohanty et al, 2021).…”

“…In the second experiment, it was observed that application of rock phosphate and triple super phosphate significantly increased cation exchange capacity and organic carbon in the soil. This means that either of the nutrients could be applied to support the residual of level of cation exchange capacity and organic carbon (Mohanty et al, 2021).…”