EFFECT OF THIOUREA ON PHOSPHORUS-USE EFFICIENCY BY POTATO (SOLANUM-TUBEROSUM) IN SHIMLA HILLS

Greenhouse and field trials were carried out on brown hill soils of shimla (Palehumults) during 1980-87 to evaluate the effect of thiourea and phosphorus on yield and nutrient uptake of potato (Solanum tuberosum L.) and soil fertility. In greenhouse study the application of thiourea had a positive effect on yield (13.1%) and P uptake (44.7%) compared with the control. Continuous application of thiourea and P significantly increased the soil P by 15 ppm compared with the control. In field trial combined application of thiourea and P gave the best results. The increase in yield was 10-20% with 5 kg thiourea, 34-49% with 44 kg P/ha and 60-70% with combined application of thiourea and P. P application increased the uptake of P(57.6%) and S(119%) compared with the control. Thiourea in combination with P increased the uptake of P(28.4%) and S(67%) compared with P application alone.