Oils from seeds produced at three locations on plants of Nugget (Brassica napus L.) and Echo (B. campestris L.) rapeseed, grown in field plots and a controlled environment room, were analyzed for their fatty acid composition. The fatty acid composition of oil from field-produced seed was not affected by the location of the seed on the plant. However, in the controlled environment room the effect of seed position was significant. Nugget seed from the lowest raceme contained seed oil with significantly higher linolenic acid and lower erucic acid than seed produced on the main raceme. Echo seed from the lowest pods on the main raceme contained significantly less palmitic acid than seeds from the lowest pods on the lowest raceme. Nugget seed grown in the controlled environment room had a significantly higher content of palmitic, stearic and oleic acids, and significantly lower levels of linoleic, linolenic and erucic acids than Nugget field-produced seed. The fatty acid composition of Echo seed oil produced under the two environments did not differ significantly. Single pod samples should be restricted to the same position on each plant to reduce the position effect on fatty acid composition. This and previous studies indicate that comparisons of fatty acid values for plants grown at different locations should be avoided.
Unconditional and conditional QTL analyses of seed fatty acid composition in Brassica napus L.
