Variabilty of oil and protein content in rapeseed cultivars affected by seeding date

Abstract

This investigation was undertaken in order to determine the variability of oil and protein content in winter rapeseed cultivars affected by seeding date. Four cultivars (Banacanka, Slavica, Express, Valesca) were sown at six seeding dates (SD1-21 August, SD2-31 August, SD3-10 September, SD4-21 September, SD5-1 October, SD6-9 October) in four replications across two cropping seasons. The trial was arranged as a randomized complete block design. The effect of year, cultivar, and seeding date were highly significant for oil and protein content. Increased oil content in the second year (2010/2011) was related to weather conditions which were favorable for rapeseed. However, protein content was significantly higher in the first year (2009/2010). Oil content ranged between 41.19% (Valesca) and 42.69% (Express). Significantly lowest oil content across seeding dates was found in SD6 (40.67%) and highest in SD4 (41.86%) and SD1 (41.61%). Valesca showed significantly highest mean protein content (21.54%). Protein content was highest in SD6 (20.18%). Oil content decreased with delayed seeding. Between oil and protein content highly significant negative correlation (r = -0.730) was stated. Seeding date showed a significant effect on oil and protein content in rapeseed. Cultivar Express and SD4 can be pointed out, based on the achieved oil content, and cultivar Valesca for high protein content. Study results may be helpful in recommending optimal rapeseed seeding date in the region.