EFFECT OF ORGANIC AND MINERAL FERTILIZERS ON VEGETATIVE GROWTH, BULB YIELD AND QUALITY OF ONION CULTIVARS

Two year study was carried out at Gemmeiza Agriculture Research Station Farm, Gharbeia Governorate, Agriculture Research Center, during 2010-2011 and 2011-2012 seasons to study the effect of organic and mineral fertilizers on vegetative growth, yield components, bulb yield and quality of some onion cultivars. The obtained results showed that Giza 20, Giza Red and Texas Early Yellow Grano X Giza 20 cultivars were significantly better in most of the studied characters in both seasons than other cultivars. Texas Early Yellow Grano X Giza 20 cultivar gave highest foliage fresh weight/plant after 120 days of transplanting, highest bulbing ratio at 90 and 120 days from transplanting, highest bulb weight and yield in both season. Mineral fertilization of onion with 214.2 kg N + 71.4 kg P2O5 + 57.1 kg K2O/ha surpassed other studied fertilization treatments and resulted in highest values of most studied characters in both seasons.. It can be concluded? that the interaction between onion cultivars and fertilization treatments significantly affected foliage fresh weight/plant at 120 days from transplanting, marketable yield, total culls and total weight loss percentage of onion bulbs after 4 months from harvesting in the second season.