EFFECT OF NITROGEN LEVELS AND ROW SPACING ON GROWTH AND YIELD OF RAPESEED

Abstract

A field experiment was conducted in the experimental field of Sher-eBangla Agricultural University, Dhaka to determine the effect of nitrogen

levels and row spacing on growth and yield of rapeseed. The experiment

consisted

of four levels of nitrogen i.e. 69 kg N ha -1 (Urea=150 kg ha

)(N 1 ), 92 kg N ha -1 (Urea=200 kg ha -1 ) (N 2 ), 115 kg N ha -1 (Urea=250 kg ha -1 ) (N 3 ) and 138 kg N ha -1 (Urea=300 kg ha -1 ) (N ); and three row spacing i.e. 20cm (S 1 ), 30cm (S 2 ) and 40cm (S 3 4 ). The experiment was laid out in a two factors split-plot design with three replications assigning nitrogen levels in the main plot and row spacing in the sub plot. Nitrogen levels, row spacing and their interactions had significant effect on plant height, number of branches plant -1 , number of siliquae plant , siliqua length, number of seeds siliqua -1 , 1000-seed weight, seed yield, stover yield, and harvest index of rapeseed. The application of N @ 115kg ha

(Urea=250 kg ha -1 ) (N 3 ) produced the highest seed yield(1393.3kg ha )of rapeseed showing the highest value for all the yield parameters except harvest index. The S (30 cm row spacing) treatment produced the highest seed yield (1060.8 kg ha 2 -1 ) of rapeseed also showing the highest values for the mentioned parameters. Application of N @ 115 kg ha with 30 cm row spacing (N 3 × S ) produced the highest seed yield. The lowest yield was found in N 2 2 (855.6kg ha -1 ), S 1 (1140.8kg ha -1 -1 -1 ) and N

(1393.3kg ha -1 ) combination.