Abstract
Integrated plant nutrition management (IPNM) approach was followed to study P use efficiency and determine its
effect on crop productivity. Phosphorus was applied @ 40 mg kg-1
as mineral fertilizer (single super phosphate,
SSP and di-ammonium phosphate, OAP) and as industrial by product (dicalcium phosphate, OCP and filter cake,
FC) either alone or after integrating in 2:1 P ratio. Wheat (cv. Inqelab-91) was grown in pots and harvested at
vegetative stage and at maturity to estimate P uptake and determine yield. Results showed that phosphorus
uptake by plants at pre-booting stage, was higher for SSP compared to all other treatments except OAP. At
maturity, however, grain and straw yield from OCP, OAP and SSP was equivalent but significantly higher than FC.
Total P uptake from OCP was significantly higher than SSP and FC supplied treatments. Integrated use of
fertilizer improved P fertilizer efficiency ranging from 4 to 37% over SSP and resulted in grain yield equivalent to
that from OCP, OAP or SSP alone. Thus integrated use of fertilizers could possibly be more economical by
replacing some of the expensive SSP with low cost by products.
Key words: Integrated fertilizer use, P efficiency, P sources, wheat