Effect of nitrogen, organic manures and bio-fertilizers on growth and bulb yield of onion (Allium cepa L.) varieties

The variety Local White (V-1) gave significantly the highest values of growth parameters viz., plant height, number of leaves per plant and leaf girth at 60, 75 and 90 days after transplanting as well as yield of onion i. e. 58.03, 55.25 and 56.64 t/ha during the years 2003-04, 2004-05 and on pooled basis, respectively, as compared to variety Agrifound Light Red (V-2) i. e, 52.43, 49.77 and 51.10 t/ha, respectively. An application of nitrogen @ 100 kg N/ha alongwith 20 t FYM/ha (IN2) recorded significantly higher plant height, number of leaves per plant and leaf girth at 60, 75 and 90 days after transplanting during both the years and in pooled analysis but, it remained at par with the treatments IN8 (N-100+PM4t), IN6 (N-100+FYM10t+BF2.5) and IN12 (N-100+PM2t+BF2.5). The bulb yield was found significantly higher in the treatment IN2 (N-100+FYM20t) i. e. 66.71, 65.23 and 65.97 t/ha during the years 2003-04, 2004-05 and on pooled basis, respectively, as compared to rest of the integrated levels of nitrogen except the treatments IN8 (N-100+PM4t), IN6 (N-100+FYM10t+BF2.5) and IN12 (N-100+PM21+BF2.5).