Effect of nitrogen and row spacing on growth, yield and economics of niger (Guizotia abyssinica)

A field experiment was conducted during the rainy season of 1998 and 1999 to study the effect of nitrogen and row spacing of niger [Guizotia abyssinica (L.f.) Cass.]. Application of 20 to 40 kg N/ha had significant favourable effect on plant height, brancheslplant, capitula/plant, test weight and biological yield. Niger seed yield increased significantly with increase in N level up to 40 kg Nlha, but stalk yield and harvest index showed significant increase only up to 20 kg Nlha. The maximum gross returns of Rs 6,771lha and net returns of Rs 3,408lha were obtained with the application of 40 kg Nlha which were 9.37 and 61.56% (gcoss returns) and 13.52 and 65.49% (nat returns) higher over 20 and 0 kg Nlha respectively. However, the maximum benefit : cost ratio(l.01) was realized with 40 kg Nlha. Closer row spacing of 15 cm increased significantly almost all the growth and yield attributes as well as seed yield and N uptake over wider row spacings of 30 and 45 cm. Row spacing of 15 cm gave maximum gross returns (Rs 6,462lha), net returns (Rs 3,447lha) and benefit :cost ratio (1.14). Key words : Niger, Guizotia abyssinica, Row spacing, Yield, Economics