EFFICIENCY OF SOURCES OF PHOSPHORUS AND BIOREGULATORS ON PIGEONPEA (CAJANUS CAJAN)

A field experiment was carried out during the rainy season of 2001 and 2002 on clay loam soil of Udaipur to study relative efficiency of sources of P, phosphorus solubilizers and bioregulators on productivity and profitability of pigeonpea ( Cajanus cajan (L.) Millsp). Among P sources, application of high grade rock phosphate (HGRP) + farm yard manure (FYM) in the ratio of 1:3+ elemental sulphur (ES) @ 25 kg/ha composted for 30 days increased seed yield by 56.6 % over control and was at par with DAP. It also improved stover and protein yield, N and P uptake and available soil P at harvest of crop. The efficiency parameters viz . relative yield, agronomic efficiency, relative economics and apparent phosphorus recovery of the above sources were also comparable to DAP. Foliar application of thiourea @ 1000 ppm and 2, 3, 5-tri-iodobenzoic acid (TIBA) @ 50 ppm at pre flowering and pod formation increased the yield of pigeonpea significantly over water spray. Application of HGRP+ FYM (1:3) + ES (25 kg / ha) also had a significant positive impact on these aspects of pigeonpea.