Effects of Fertilizer Levels and Weed Control Measures on Growth and Yield of White Onion (Allium cepa) under North Konkan Coastal Zone of Maharashtra

Abstract

A field experiment was conducted at the district fruit nursery, Alibag (Maharashtra) to study the effect of fertilizer levels and weed management measures on growth and yield of white onion (Allium cepa) under North Konkan Coastal Zone of Maharashtra state. The crop was fertilized with four levels viz., 75% RDF, 100% RDF (100:50:50 kg NPK ha^-1), 125% RDF and fertilizer application on the basis of soil test. Six weed management measures comprised weedy check, one hand weeding at 20 DAT, two hand weeding at 20 and 50 DAT, oxyfluorfen spray @ 0.176 kg ha^-1, oxyfluorfen spray @ 0.176 kg ha^-1 + one hand weeding at 50 DAT and weed free check. Application of fertilizers on the basis of soil test (150:75:25 kg NPK ha^-1) recorded significantly higher bulb yield (239.17 q ha^-1) as compared to remaining fertilizer levels except 125% RDF. Significantly higher bulb yield (253.33 q ha^-1) was recorded in weed free check as compared to weedy check and one hand weeding at 20 DAT. The highest weed control efficiency (95.03%) was recorded in weed free check followed by application of oxyfluorfen combined with one hand weeding at 50 DAT while the highest weed competition index (66.14%) was recorded in weedy check. Maximum net returns (Rs. 399613 ha^-1) with higher B:C ratio (1:3.11) were obtained when onion crop was fertilized on the basis of soil test and herbicide oxyfluorfen @ 0.176 kg ha^-1 combined with one hand weeding at 50 DAT. Significantly higher nitrogen, phosphorus and potassium uptake were recorded when onion crop was fertilized on the basis of soil analysis and crop was kept weed free throughout the growth period.