Influence of Sowing Properties on Winter Oilseed Rape in a Sub-humid Mediterranean Environment

Abstract

The effects of three row spacings (17.5, 35.0 and 52.5 cm) and four seeding rates (100, 200, 300 and 400 viable seeds m-2) on seed yield and some yield components of winter oilseed rape (Brassica napus L.) were evaluated under rainfed conditions in Bursa, Turkey in the 2005-2006 and 2006-2007 growing seasons. Row spacing and seeding rate significantly affected most yield components measured. The number of plants per unit area increased with increasing seeding rate and decreasing row spacing. Greater plant heights were obtained from narrow row spacings and higher seeding rates. Narrow row spacings and higher seeding rates reduced the number of primary branches and the number of pods per terminal raceme. Also, the number of seeds per pod and 1000-seed weight were not affected by either row spacing or seeding rate. In contrast, the number of pods per plant clearly increased with increasing row spacing but decreased with increasing seeding rate. The highest seed yields were obtained for the 17.5 cm row spacing (1709.2 kg ha-1) and 200-seeds m-2 seeding rate (1721.4 kg ha-1).