Nutrient uptake, post-harvest soil nutrient status and economic returns from sunflower (Helianthus annuus L.) hybrids under different tillage and nutrient levels on lowland rice fallow environments of Odisha

Abstract

A field experiment was conducted at College of Agriculture, Odisha University of Agriculture and Technology, Bhubaneswar on sandy loam soils during summer season of 2019 to study the effect of varied nutrient doses and tillage on the nutrient uptake and economics ofsunflower (Helianthus annuus L.) hybrids under lowland rice fallow environments. Three sunflower hybrids viz., DRSH-1, KBSH-44 and MSFH-17 were tested under three gradedfertility levels RDF (recommended dose of fertilizers), 50% RDF (30: 40: 30 kg N: P2O5 : K2O /ha), 100% RDF (60: 80: 60 kg N: P2O5 : K2O /ha) and 150% RDF (90:120:90 kg N: P2O5: K2O/ha) and four tillage practices viz., reduced,minimum, zero tillage and conventional tillage practice. Sunflower under zero tillage recorded the highest uptake of N (52.65 kg /ha), P (21.87 kg/ha) and K (76.03 kg/ha) besides highest seed yield (1.91 t/ha). On the other hand,conventional tillage recorded the highest post-harvest soil available nitrogen (216.6 kg /ha), phosphorous (12.9 kg/ha) and potassium (214.4 kg/ha). Among the hybrids, KBSH-44 recorded significantly higher seed yield (1.81t/ha) besides highest nutrient uptake. Raising sunflower hybrid KBSH-44 under rice fallow zero tillage conditions and fertilized with 150% RDF (90:120:90 kg N: P2O5 : K2O/ha) was found economically superior in terms of gross returns, net returns and B: C ratio (2.34).