Growth and yield of rainfed sunflwoer (Helianthus annuus L.) as influenced by humic acid under nutrient management practices 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 growth parameters, SPAD, yield attributes and yield 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 results revealed that among the nutrient management practices plant height at 30 and 45 DAS (30.6 and 75.20cm) SPAD readings at 30 DAS (40.50), seed yield/plant (33.85g), test weight (50.3g/1000) seed, stalk and oil yield (1859, 3555 and 741kg/ha) and harvest index (26.30%) were highest with the combined application of RDF (60-60-30 N, P2O5, K2O kg/ha) + Compost @ 5t/ha and it was on par with M5- RDF+ Compost @5t/ha while, the lowest yield attributes and yield were under absolute control. The effect of different levels of humic acid as well as the interaction effect was found to be non-significant on plant height, SPAD readings, yield attributes and yield. However, interaction effect was significant on plant height at harvest.