- Compared five RPR’s and single super phosphate (SSP).
- Phosphorus applied annually (1992-95).
- Four different application rates were trialled.
- Dry matter was collected annually (1992-99).
At 17 kg/ha RPR produced more dry matter than SSP in every year of the trial. RPR produced more dry matter than SSP once applications of P ceased (1995) until the end of the trial recording period (2000).
CSIRO Publishing, Australian Journal of Experimental Agriculture, 1997