Effect of nitrogen, phosphorus and sulphur fertilization on productivity, nutrient-use efficiency and economics of safflower (Carthamus tinctorius) under late-sown condition

A field experiment was conducted at Varanasi during winter (rabi) seasons of 2009–10 and 2010–11 to study the effect of nitrogen, phosphorus and sulphur fertilization on productivity, nutrient-use efficiency and economics of safflower (Carthamus tinctorius L.) under late-sown condition. An application of 80 kg N/ha, 80 kg P₂O₅/ha and 60 kg S/ha significantly increased the seed yield with concomitant increase in yield attributes. Enhanced supply of N or P or S reduced the agronomic efficiency (AE) apparent recovery (AR) and physiological efficiency (PE) and the highest efficiency of these respective nutrients was recorded with 40 kg N, 40 kg P₂O₅ and 20 kg S/ha, and the lowest with 80 kg N/ha, 80 kg P₂O₅/ha and 60 kg S/ha. Maximum net returns/ha were obtained with 80 kg N ( 29,400/ha), 80 kg P₂O₅ ( 25,500/ha) and 20 kg S/ha ( 22,800/ha). The seed yield response to tested levels of nitrogen, phosphorus and sulphur was found quadratic. The economic optimum dose of nitrogen, phosphorus and sulphur for safflower was calculated from regression equations to be 79.0, 77.7 and 53.1 kg/ha respectively.