中文摘要：

为了解白菜型和甘蓝型冬油菜抗寒基因的表达差异,以6个抗寒性不同的冬油菜为材料,利用实时荧光定量PCR（qRT-PCR）分析常温对照以及4℃、-4℃和-8℃低温处理5d后Bn COR25、Bn ICE1和Cu/Zn-SOD三个基因的表达差异。结果表明,常温时白菜型与甘蓝型冬油菜Bn COR25、Bn ICE1和Cu/Zn-SOD基因未被激活,处于同一水平;随着温度的降低,白菜型冬油菜Bn COR25、Bn ICE1和Cu/Zn-SOD的相对表达量均上升,且均在-4℃时到达峰值;而甘蓝型冬油菜Bn COR25在4℃时到达峰值,Cu/Zn-SOD在-4℃时到达峰值,Bn ICE1的相对表达量在低温胁迫过程中始终低于常温水平;-8℃时白菜型与甘蓝型冬油菜各基因表达量均下降。在整个温度降低过程中,始终表现为白菜型冬油菜Bn COR25、Bn ICE1和Cu/Zn-SOD的相对表达量显著高于甘蓝型冬油菜,抗寒性强的品种高于抗寒性弱的品种。说明,白菜型与甘蓝型冬油菜间抗寒性的较大差异与这3个基因的表达有关。

英文摘要：

To understand different cold- tolerance of Brassica rapa and B. napus,3 genes were investigated under chilling stresses at 4℃,- 4℃ and- 8℃. The genes included Bn COR25（ from B. napus）,Bn ICE1（ from B. napus）,and Cu / Zn- SOD（ from B. rapa）. 6 different cold- resistant winter rapeseeds were used as materials and analyzed after 5d chilling treatments and normal control（ at 24℃,CK）. qRT- PCR results showed that BnCOR25,Bn ICE1 and Cu / Zn- SOD were not activated and expressed at the same level in both B. rapa and B. napus at 24℃. Under chilling,their relative expressions in B. rapa increased when the temperature decreased,and reached to the peak at- 4℃. Among them,Bn COR25 reached the peak at 4℃ and Cu / Zn- SOD at- 4℃ in B.napus. Bn ICE1 expression was always lower than CK. At- 8℃,genes expressions of both types were decreased and low. Compared to B. napus,these 3 genes expressions in B. rapa were significantly higher. Compared to cold-sensitive rapeseed,those with higher cold tolerance had higher expression. It indicated that cold- tolerance was related to these 3 genes and two types of rapeseed had their different responses.