Evaluation of the Risks of Contaminating Low Erucic Acid Rapeseed with High Erucic Rapeseed and Identification of Mitigation Strategies

Abstract

High erucic acid rapeseed (HEAR) oil is under increasing demand for various industrial applications. However, many growers are concerned that if they grow the crop, they will not be able to revert to other rapeseed varieties in the future due to the risk of erucic acid (EA) contamination of the harvested seed and inability to maintain acceptable erucic acid thresholds. This review considered published literature and, using the same criteria as that used to contain transgenic crops, aimed to identify the key risks of erucic acid contamination, broadly prioritise them and identify pragmatic mitigation options. Oilseed rape has a number of traits that increase the risk of low erucic acid rapeseed (LEAR) crops being contaminated with EA from HEAR varieties. The quantity of seed produced and the potential for seed dormancy coupled with partial autogamy (self-fertilisation) facilitate the establishment and persistence of volunteer and feral populations. The large quantities of pollen produced when the crop is in flower mean there is also a high potential for cross-pollination. Self-sown volunteer plants represent the highest potential contamination risk, followed by the presence of arable weeds (e.g., wild mustard) whose seeds are also high in EA. Other risks arise from the cross-pollination of compatible wild relatives and the mixing of seed prior to sowing. It is important that both HEAR and LEAR varieties are appropriately managed since risks and their potential for mitigation arise throughout the entire LEAR crop production process. The length of rotation, type of tillage, cultivar choice, buffer zones, effective weed management and basic machinery hygiene are all factors that can reduce the risk of erucic acid contamination of LEAR crops and maintain the required thresholds.

Genome Structures and Evolution Analysis of Hsp90 Gene Family in Brassica napus Reveal the Possible Roles of Members in Response to Salt Stress and the Infection of Sclerotinia sclerotiorum

“…Seeds of rapeseed are rich in fat (40–49%) and suitable for producing edible oil. It can also be used for animal feed for its high protein content as well as industrial purposes, such as high-quality lubricant ( Warner and Lewis, 2019 ). B. napus is a heteropolyploid species formed by natural hybridization.…”

Crambe: Seed Yield and Quality in Response to Nitrogen and Sulfur—A Case Study in Northeastern Poland

“…However, the cultivation of HEAR with other rapeseed cultivars (such as low erucic acid rape, LEAR, for food processing) is difficult due to high levels of gene flow mediated by pollen (cross pollination) and seeds (seed shedding during maturation and harvest, and a long period of secondary dormancy) [5,6]. In LEAR production, the risk of EA contamination from HEAR varieties is difficult to control and requires numerous adjustments, including appropriate crop rotations with a low share of Brassica crops, the establishment of buffer zones, and effective control of weeds, in particular of the family Brassicaceae [6]. At present, the oil from C. abyssinica seeds (synonym: Abyssinian oil) is favored over HEAR oil due to a higher content of EA (50-60% vs. 45-50%) conditions.…”

The Use of Genetic and Gene Technologies in Shaping Modern Rapeseed Cultivars (Brassica napus L.)

“…Regarding renewable and sustainable resources, erucic acid from canola oil is an excellent raw material in producing polymers used in film manufacture, nylon, lubricant, and emolient industries [ 13 , 17 ]. Furthermore, with the increasing demand of canola oil for food and efforts to promote renewable resources of high erucic acid rapeseed (HEAR, 45–60% erucic acid), varieties have been grown in European countries for biofuel and raw oil supplement (<2% of total weight of crushed seeds) for human consumption [ 88 , 89 ]. By overexpressing the fatty acid elongase gene ( fae1 ) simultaneously with the lysophosphatidic acid acyltransferase gene from Limnanthes douglasii (Ld-LPAAT), erucic acid synthesis was predominant over PUFA synthesis in competitive elongation to the triaclyglycerol backbone in transgenic lines, which resulted in an increase in erucic acid content of up to 72% and a PUFA content as low as 6% [ 13 ].…”