Effect of organic and inorganic sources of nutrients on spring sunflower (Helianthus annuus L.)- maize (zea mays L.) sequence- P S Bodake, D S Rana

Abstract

A fixed p lot experiment was conducted during 2007 and 2008 at research farm of Division of Agronomy, IARI, New Delhi to explore the possibility of an alternative to farm yard manure (FYM) as a component of integrated nutrient management in spring sunflower-maize sequence. The three organic sources like jatropha cake, castor cake and FYM were applied at 100%, 50% and 25% level of recommended dose of nitrogen (RDN) in integration with 0%, 50% and 75% inorganic fertilizer (RDF) at all combination as well as control. Recommended dose of fertilizer, 80, 26.2 and 30 kg NPK/ ha to sunflower and last treatment fallow followed by 100% RDF to maize and their residual effect on succeeding maize crop. The direct, residual and residual cumulative effect of organic sources significantly affected the system productivity of spring sunflower-maize sequence. Statistically significant seed yield of spring sunflower (2.64 t/ ha) was on par with 75% RDF + 25% RDN through jatropha cake (2.61 t/ ha) in 2007 and 50% RDF + 50% RD through jatropha cake (3.43 t/ ha) was on par with 50% RDF + 50% RON through castor cake (3.36 t/ ha) in 2008 over control. Residual and residual cumulative effect of maize has shown a statistically significant yield with 50% RDF + 50% RD through jatropha cake (2.72 and 2.89 t/ha) followed by 50% RDF + 50% RD through castor cake (2.45 and 2.62 t/ha) in both the years. The nutrient uptake (102.4 and 139.9 kg / ha; 36.5 and 44.9 kg P/ha and 106.9 and 156.5 kg K/ha and net returns (Rs 36,292/ha and Rs 49,531/ha) were recorded with RDF (80, 26.2 and 82.3 kg/ ha) and 50% RDF + 50% RD through jatropha cake in 2007 and 2008, respectively. The residual effect of fertility levels showed a higher system productivity and system economics was 3.52 and 4.75 t/ha and net returns (Rs 45,518/ha and 69,407 /ha) and B:C ratio (2.20 and 3.24) was recorded with 50% RDF + 50% RDN through jatropha cake during the sequence in both the years.