EFFECT OF TRANSPLANTING DATES OF SOME ONION CULTIVARS ON VEGETATIVE GROWTH, BULB YIELD AND ITS QUALITY

In order to study effect of transplanting dates on vegetative growth, bulb yield and its components of some local onion cultivars. Two field experiments were conducted at Gemmeiza Agriculture Research Station Farm, Gharbeia Governorate, Agriculture Research Center, Egypt during 2010/2011 and 2011/2012 seasons Results showed that transplanting onion seedlings on 15 th December recorded highest averages of foliage fresh weight/plant at 90 and 120 days from transplanting, total yield, marketable yield and averages bulb weight, total soluble solids, dry matter and total weight loss percentages of onion bulbs every month after harvesting till end of storability. Highest bulbing ratios at 90 and 120 days from transplanting in the second season, total yield and marketable yield, total culls and bulb weight as well as total weight loss percentage of onion bulbs every month after harvesting till end of storability in both seasons were produced from Texas Early Yellow Grano X Giza 20 cultivar. A significant interaction was produced between transplanting dates of some  onion cultivars in foliage fresh weight/plant at 90 days from transplanting, marketable yield, total culls. According to the obtained results from this study, it can be concluded that, transplanting seedlings of Texas Early Yellow Grano X Giza 20 cultivar on 15 th December or 1 st January to maximize productivity and bulb quality under the environmental conditions of Middle Delta, Gharbeia Governorate.