College of Agriculture, Central Agricultural University, Imphal - 795004 (Manipur).
An experiment consisted of 3 levels of spacing (51 – 10×l0 cm, 52 15×15 cm and 53 – 20×l0 cm) and 3 levels of bulb size (B1 - 0.5 to 1.5 g, B2 - 1.5 to 2.5 g and B3 - > 2.5 g) was conducted during rabi seasons of 2003–04 and 2004–05 to study the effect of spacing and bulb size on the growth and yield onion. The maximumyield was with closer spacing (S1) and bigger bulb size (B3). Among the different levels of spacing (20 × 10 cm) recorded maximum number of leaves per hill, number of bulbs per hill, and also in most of the bulb characters, but highest yield (172–184 q/ha) was recorded in closer spacing (10 × 10 cm). Bulb size also influenced significantly the growth parameters like number of leaves per hill, leaf length and bulb characters like fresh weight and dry weight, The maximum yield was recorded with biggest buld size i.e. > 2.5 gm. The best treatment combination was S1 B3 which recorded highest benefit cost ratio (3.68: 1).
