Yielding of winter oilseed rape as influenced by different sowing dates

Abstract

Field experiment was carried out in 2008–2010 at the Experimental Station of Aleksandras Stulginskis University. The soil of the experimental site – Hapli-Epihypogleyic Luvisol. Treatments of the experiment: factor A – sowing date: 1) August 10; 2) August 20; 3) August 30; 4) September 5 (in 2009); 5) September 10; 6) September 15 (in 2009). Factor B – winter rape varieties: ‘Sunday’ and hybrid ‘Kronos’. Sowing date exerted a significant impact on winter rape seed yield structural elements. However, these changes were not as dramatic for hybrid rape as for ‛Sunday’ variety. In most cases there were found no significant differences of yield structural elements between the different varieties. Sowing date effect on rapeseed yield was significant: the highest seed yield was obtained for the sowing dates August 20 and 30, while the lowest for August 10 and September 10. When sown on the latter dates, the seed yield of the ‘Kronos’ hybrids was significantly higher compared with that of ‘Sunday’ variety.