Weather, Quality parameers and yield of rainfed sunflower (Helianthus annuus L) under integrated nutrient management in Alfisols

Abstract

A field experiment on rainfed sunflower was conducted during kharif 2014 at College agriculture farm, College of Agriculture, Rajendranagar, Hyderabad to study the effect of humic acid under nutrient management practices on seed yield, oil yield, protein yield, volume weight and hull content of rainfed sunflower. The experiment was laid out in Split plot design with eigthteen treatments (Six main and three sub-treatments and replicated thrice). The six main treatments consisted of M1-Absolute control, M2 - compost @ 2.5t/ha, M3-Compost @ 5t/ha, M4- RDF alone (60-60-30 kg N, P2O5,K2O/ha), M5- RDF+ compost @ 2.5t/ha and M6- RDF+compost @ 5t/ha and three sub-plot treatments consisted of application of varying levels of humic acid granules (basal) viz., S1 - 5.0kg/ha, S2- 10.0 kg/ha and S3- 15.0kg/ha. The crop was grown completely under rainfed conditions. During the crop growth period (July 9 to Oct 9) a total of 329.7mm rainfall was received in 24 rainy days and it was deficit by 57.14% over the decennial average of 519.1mm received in 30 rainy days. A total of 11 dry spells occurred during the crop growth period coinciding with the vegetative (5) and reproductive stages (6). The results revealed that among all the nutrient management practices maximum seed, oil and protein yield (1959, 741 and 224 kg/ha, respectively) was recorded with the combined application of RDF (60-60-30 N, P2O5, K2O kg/ha) + Compost @ 5t/ha and the lowest oil yield, protein and seed yield were observed under absolute control. The effect of varying levels of humic acid was found to be non significant on oil yield, protein yield and seed yield.