Increasing erucic acid content in rapeseed (Brassica napus L.)

摘要

High erucic acid rapeseed (HEAR) cultivars are regaining interest for industrial purposes because erucic acid (22:1) and its derivatives are important renewable raw materials for the oleochemical industry. For oleochemical use, it is desirable to increase 22:1 content from now 50-60% to 80% and more. This would significantly reduce processing costs and would increase the market prospects of HEAR oil. In the present experiment, the transgenic winter rapeseed genotype 361.2B (60% 22:1, 19% 18:2+18:3)over expressing thefael-gene in combination with a LPAAT plsC-gene from Limnanthes douglasii was crossed with the high erucic acid winter rapeseed line 6575-1 with a low content of polyunsaturated fatty acids (HELP; 50% 22:1,7% polyunsaturated fatty acids) with the hypothesis that this would result in an increased 22:1 content in the seed oil 220 F2 plants derived from this cross were grown in the greenhouse and bagged at flowering. F3 seeds were harvested and analysed for fatty acid composition and trierucoylglycerol (trierucin) content. Recombinant F2 plants with 68-72% 22:1, 9-14% polyunsaturated fatty acids and with trierucin content up to 25% were identified, indicating a 5-10% increase in 22:1 content compared to parent 361.2B. Results will be confirmed by testing F3 plants from selected F2 plants in the greenhouse. Additional steps required to achieve 80% or more 22:1 in the seed oil are discussed.