Correlation Analysis Of The Differential Expressions Of Fad₂ Gene And The Fatty Acid Biosynthesis In Brassica Napus L.

Oilseed rape is one of the most important oil crops in China.China has the largest total planting area and the highest total product in the world.In rapeseed oil, oleic acid(C18:1) is a kind of the main nutrition which can be absorbed by human body;linolenic acid is necessary for brain development.So,it is a significant objective of quality breeding to increase the contents of oleate in rapeseed,which is extraordinarily useful for the synthesis of biodiesel and development of new energy resources.In the existing Low erucic acid rapeseeds(LEAR),the content of oleic is correlated to process of its desaturation to linoleic,which is controlled by fad₂ gene.This study analysed the differences of the expression of fad₂ gene in XIANGYOU NO.15 with different treatments,using RT-PCR technique.We have found out the accumulation pattern of major fatty acid with these materials.Also,we studied the effects of different temperature treatments on the expression of fad₂ gene and the accumulation pattern of oleic and linoleic in XIANGYOU NO.15.The main achievement of the study were as follows:1.The expression of fad₂ gene in the high oleic acid rapeseed(HOAR) mutants 1017 and 1036 was significantly higher than that in normal XIANGYOU NO.15 during the whole growth period,while the content of linoleic acid was significantly lower than that in normal materials.The results indicated that the expression of fad₂ gene was significantly negative correlation to the cumulation of oleic acid,and was significantly positive correlation to that of linoleic acid.2.The results showed that the biosynthetic patterns of oleic acid(C18:1) presented an "Ascent——Flat——Descent" pattern,which accumulated predominantly during the first 14 to 35 days after pollination(DAP);while the biosynthetic patterns of linoleic acid(C18:2) presented an "Ascent——Flat——Ascent" pattern,of which the lowest percentage happened during the more than 20 DAP.3.The expression of fad₂ gene and the acumulation of oleic acid and linoleic acid presented some extent of period variability.The effects of temperature on them were not obvious during the whole seed development except that during the special period the effects were significantly different.