Sėjos laiko ir veislės įtaka žieminių rapsų pasiruošimui žiemoti sėjos laiko ir veislės įtaka žieminių rapsų pasiruošimui žiemoti

Abstract

Field experiments were carried out in 2012–2013 at the Experimental Station of Aleksandras Stulginskis University. The soil of the experimental site – limnoglacional silty loam on moraine clay loam Hapli-Epihypogleyic Luvisol. - Idg8-p(LVg-p-w-ha). Soil pH 6.5–7.2, total nitrogen 1.47–1.59 percent, humus 2.2–3.0 percent, available phosphorus 173–235 mg kg-1, available potassium 115–189 mg kg-1, available sulfur 5.6–26.4 mg kg-1 soil. Our study aims to identify winter oilseed rape development patterns in the changing climatic conditions and adaptation measures (sowing time) which ensure good plant preparation for the winter. Winter rapeseed crowns development of different sowing time and dry matter accumulation by the end of autumn vegetation season affected the plant preparation for winter. Strong to moderate statistically reliable correlative relationship was identified between dry matter quantity and the amount of positive temperatures and sunshine duration. It was determined that winter rape sown on August 10th and 20th was best prepared for the winter according to the biometric parameters. Delaying sowing until September 10th showed that biometric indicators did not meet the good characteristics of plants ready to hibernate. Hybrid rape was less sensitive to the time of sowing , growing rapidly until the end of the growing season in autumn , their biometric parameters were higher, and they have accumulated more dry matter.