【作者】 邓婧；

【导师】 李栒；

【作者基本信息】 湖南农业大学 ， 作物遗传育种， 2008， 硕士

【摘要】 提高油酸含量是油菜品质育种的一个重要目标,有利于生物柴油的生产和新能源的开发。在现有的低芥酸油菜中,油酸的含量与油酸是否进一步减饱和转化为亚油酸有关。而油酸减饱和酶基因fad₂是控制减饱和反应的关键。本研究运用RT—PCR技术研究湘油15号品种中不同处理材料的fad₂基因表达差异,以及这些材料的脂肪酸积累模式:并对湘油15号进行不同温度的处理,研究温度对fad₂基因表达和油酸、亚油酸的影响。主要研究结果如下:1、普通的湘油15号材料的fad₂基因表达量在油菜种子发育的各个时期都显著高于高油酸突变的湘油15号材料,而油酸含量则显著低于高油酸突变材料。证明fad₂基因的表达与油酸积累呈显著负相关,与亚油酸积累显著正相关。2、在甘蓝型油菜中,油酸积累的过程是“升——平——降”模式,油酸的主要积累时期为授粉后第14～35天。亚油酸积累模式为“升——降——升”,亚油酸含量的最低值出现在授粉后第20多天。3、fad₂基因表达量和油酸、亚油酸的积累都具有明显的时期变化性。温度对fad₂基因表达的变化不显著,对油酸、亚油酸积累的影响也不显著;但是授粉后在不同的时期内,温度对它们的影响却是显著的。更多还原

【Abstract】 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.更多还原