Effect of fertility levels on mustard (Brassica juncea) seed yield, quality and economics under varying poplar (Populus deltoides) tree densities

Abstract

An experiment was conducted during rabi of 2008-09 and 2009-10 at Pantnagar, to study the effect of different doses of recommended fertilizers on yield and yield attributes, seed quality, economics and nutrient balance of In- dian mustard ( Brassica juncea L.), under varying poplar ( Populus deltoides Bartr. Ex. Marsh.) tree densities. Seed yield, oil content and oil yields were not influenced significantly by tree densities in both the years. However, glucosinolate content was improved underneath trees. Maximum benefit: cost ratio from crop was obtained in sole crop with 100% RDF and from agrisilvicultural system (7.81) under 1000 trees/ha density with 50% RDF. With an increase in recommended dose of fertilizer (RDF), seed and stover yields increased significantly upto 100% (1.04 t/ha and 3.41 t/ha) and 125% of RDF (2.03 t/ha and 6.0 t/ha) in 2008-09 and 2009-10, respectively. Oil content de- creased but oil yield (340 and 627 kg/ha) and protein content (23.7 and 22.9%) improved significantly upto 100% of RDF in both the years. Similarly, protein yields (245 and 456 kg/ha) and glucosinolate content (80.3 and 87.6 mM/g of seed) increased upto 100 and 125% of RDF in 2008-09 and 2009-10, respectively. A density of 1,000 trees/ha and 100% RDF (120 kg N + 17.4 kg P O + 16.6 kg K O/ha) was found most suitable and economical for 2 5 2 mustardpoplar mixed agrisilvicultural system.