Abstract:
Potted plant studies were conducted in five major rice soils of Kerala
namely karappadom, laterite, kayal, coastal sandy and kole soils to evaluate the
efficiency of primed rock phosphate in moist aerobic soil with superphospate applied
at flooding. Fractionation studies on the fate of applied phosphate revealed that
priming of rock phosphate in moist aerobic soil resulted insubstantial conversion
of phosphate to iron phosphate and aluminium phosphate and these products
increased availability of phosphorus to rice on submergence. Primed rock phosphate
was found to be as efficient as superphosphate in karappadom, kayal and coastal
sandy soil in yield and uptake of phosphorus. But in laterite soil it was found to
be significantly superior to superphosphate.
