Investigating Yield, Yield Components and Some Qualitative Traits of Bulb in Iranian Improved Onion (Allium cepa L.) Red Rey Cultivar

The purpose of this two years research (2016-2017) conducted in Karaj is to investigate quantitative and qualitative traits of bulb in Red Rey Iranian improved onion ((Allium cepa L.) population Red Azarshahr as check in terms of increasing yield of bulb and qualitative traits especially in DM percentage. The improved population was achieved by the selection of superior bulbs, cultivation and its selfing and consequently the identification of the best families and conduction of open pollination between them. In April 2016, the improved population with basic population and Red Azarshahr improved cultivar (as a comparative cultivar as check) were evaluated in RCBD design at three replicate and the different traits were measured including total yield, bulb weight, bulb diameter, bulb height, number of bulb layers, the number of bulb centers, bulb firmness, dry matter of bulb, total sulfur content, total phosphorus content, total potassium content in bulb and the amount of bulb vitamin C. The results showed that the improved population was than basic population in various traits especially in bulb yield with 98.9 tons per hectare, but there was no superiority in improved population in proportion to basic population or check cultivar in qualitative traits of bulb particularly qualitative laboratorial characteristic (sulfur, phosphorus, potassium and vitamin C) except for dry matter percent and bulb firmness.