Breeding progress towards high oil content in oilseed rape (Brassica napus L.)- essential innovations to meet current and future market needs

摘要

High contents of oil do increase the general profitability in rapeseed and deliver significant advantages for all partners of the oilseed chain (e.g., farmers gain due to a higher gross margin and oil crushers achieve a higher margin and oil yield output per crushed seed unit). Furthermore, limited resources are used more efficiently and the energy and ecology balance is improved. In spite of its polygenic inheritance the oil content is genetically highly stable and genotype by environment interactions are relatively low. Reproducible analysis methods like the near-infrared-reflectance-spectroscopy (NIRS) can be used for a high throughput screening on undestroyed, intact seeds, have enabled breeders to effectively screen very large numbers of genotypes in a very short time. In total, this has led to significant improvements of the oil content and continuous breeding progress. Over a period of ten years (1995-2004), an average annual increase of 0,16% can be calculated for the oil content in the official variety trials of winter oilseed rape in Germany. Examples for resulting products of the past systematic breeding activities are the recently in Germany and Great Britain released winter oilseed rape varieties Oase, Lioness and Billy which combine a high oil content with a very high seed yield and a nice agronomic performance package. Since the oil content is the last yield component formed plant health resp. a high disease resistance is essential to exploit the genetically fixed potential for oil yield. In addition, crops have to reach complete maturity in order to realize the full potential. The advantages of a higher oil content have been recognized in several countries and are mostly rewarded in a respective premium system by a higher price for the farmer. Premium systems differ considerably and have significant effects on the variety choice and, finally, also on the profitability and compettive ability of the rapeseed cultivation.