Efficiency of Rock Phosphate Sources on Ginger and Turmeric in an Ustic Humitropept

Field experiment was conducted for three years (1995–98) to study the efficacy of different sources of rock phosphates in an Ustic Humitropept on nntrient availability, yield, agronomic efficiency and quality of ginger and turmeric. Bray's available P increased with the application of rock phosphates mixed with FYM and among the sources Raj phos was superior. Rhizome P concentration was higher when superphosphate and FYM incuhated rock phosphates were applied. Significantly higher dry yield in turmeric was registered in Gafsa phos followed by Raj phos when incubated with FYM. Similar trend was observed in ginger with Raj phos and Gafsa phos application with FYM, and it was significantly higher than other sources of P applied. Not much variation was observed in oleoresin and curcumin contents of ginger and turmeric due to application of different sources of P. Among all the sources, apparent phosphate recovery, agronomic efficiency of the applied P and per cent yield response were higher for Gafsa phos followed by Raj phos incubated with FYM in both ginger and turmeric.