Influence of growing intensity and variety on production markers and winter rapeseed quality (Brassica napus L. var. napus)

摘要

In Czech Republic the share of winter rapeseed crop cultivation is approximately 10 -11% of total acreage arable land. In practical cultivation is about 45 varieties of winter rapeseed. The restored hybrid varieties occupy 15 - 20% and the composite hybrids have a little share - about 3 -5%.acreage total of rapeseed. The rapeseed cultivate approximately from 170 to 750 m above sea - level, on soils with content mould 1 - 1,5% as well 2,0 - 2,5% mean annual precipitation 450-500 mm and the average annual temperature from 7 - 80C to 9 - 120 C. The rapeseed cultivate always with herbicide and insecticide. In standard intensity of cultivation give 100-150 kg N/ha without fungicides and growth regulators. In a higher intensity of inputs applicates 190 - 220 kg N/ha with fungicide, regulators, stimulators and leaf fertilizers. Therefore the yields fluctuate general from 2,0 to 5,0 t/ha. In trials on 8 localities in 2002/03, 2003/04, 2004/05 years observed reaction of winter rapeseed varieties at two different intensities of cultivation: the standard and the higher intensity of cultivation in relation with production and economy. The results show only about 3 -4% difference in seed yields among hybrid and line varieties of rapeseed. Some line variety always occurred which overcame average hybrids in seed yields. The standard intensity of cultivation showed average seed yields 3,72t/ha, the higher intensity 4,13t/ha (113%) during three years. In the successful rapeseed years the yield differences among intensities were low, but in critical years the differences increased. Therefore, the returns of the invested investments into the intensive technology need not be economically positive. The higher intensity of cultivation had about 10% more branches/m, about 7% more pods on terminal, 17% lower of dried up buds and oil content in seed was lower. Dry, warm years and localities had marked lower oil content.