Productivity, nutrient uptake and profitability of hybrid sunflower (Helianthus annuus) as influenced by irrigation and fertilizer-management practices under sub-tropical climate of West Bengal

Abstract

An experiment was conducted at farmers field at Madandanga, Gayeshpur, Nadia, West Bengal during the winter seasons 201112 and 201213, to study the effect of water and nutrient-management practices on growth and yield of hybrid sunflower (Helianthus annuus L.). The experiment was laid out in split-plot design, assigning 3 irrigation levels in the main plot and 7 fertilizer treatments in the sub-plots. The experiment consisted of 21 treat- ment combinations replicated thrice. Results revealed that N P K B S (80, 40, 40, 1.5 and 25 kg/ha of N, 80 40 40 1.5 25 P O , K O, B and S respectively) treatment significantly and synergistically increased plant height at 100 days af- 2 5 2 ter sowing (DAS), leaf-area index at 75 DAS, total dry-matter accumulation at 100 DAS, crop-growth rate during 5075 DAS, basal girth at harvesting and capitulum diameter of hybrid sunflower (9.6, 65.1, 49.7, 49.0, 11.6 and 11.9% higher values than the crop in farmer fertilizer practice (FFP) plot respectively). The yield attributes, namely filled seeds/capitulum, filled seed weight/capitulum, total seed weight/capitulum and 100-seed weight, were signifi- cantly higher by 52.8, 63.5, 38.6 and 16.9% when grown with 3 irrigations, given at 30, 60 and 80 days after sow- ing (I ) than the plants receiving 1 irrigation (I ) and 75.7, 73.2, 97.8 and 30.0% with N P K B S treatment 30/60/80 30 80 40 40 1.5 25 than the FFP plots. Average seed and stalk yield of sunflower Aditya was the highest in I treatment, ac- 30/60/80 counting 44.1 and 78.8% more than the crop yield obtained under I treatment, respectively. Application of 30 N P K B S resulted in significantly higher seed and stalk yield (38.6 and 48.1% more than the values in FFP 80 40 40 1.5 25 plots). Irrigation with I resulted 1.2% more oil percentage compared to the I treatment. The oil content of 30/60/80 30 tested cultivar was significantly and synergistically increased by the application of N P K B S , accounting 80 40 40 1.5 25 6.4% more than that obtained with FFP. Irrigation fertilizer interaction had significant effect on oil content and the highest value was observed to be in seeds obtained in plots fertilized with N P K B S under 2 irrigations (I 80 40 40 1.5 25 30/ ). The maximum net return and benefit: cost ratio were recorded with the crop irrigated thrice (I ), accounting 60 30/60/80 118 and 35%, respectively, more over the crop irrigated once (I ). Irrespective of irrigation levels, combined appli- 30 cation of NPK and B (N P K B ) resulted in the highest net returns and benefit: cost ratio among all fertilization 80 40 40 1.5 practices, accounting 52 and 23%, respectively more over the crop fertilized with N P K (FFP). 60 30 30