中文摘要：

为深入了解抗寒生理机制,阐明白菜型冬油菜抗寒性与内源ABA含量的相关性,以超强抗寒性品种（陇油6号、陇油7号）与耐寒性品种（天油2号、天油4号）为材料,研究越冬前低温胁迫后冬油菜在大田自然降温情况下叶片与根系中内源ABA含量的变化。结果表明,除天油4号,随着气温的降低,冬油菜ABA含量逐渐升高,不同抗寒性品种增加幅度不同,超强抗寒性品种（陇油6号、陇油7号）的根系及叶片的ABA含量升高时期早于耐寒性品种（天油2号）。相关性分析表明,与叶片相比,根系ABA含量与冬油菜的越冬率之间的相关系数更高;而同一时期,各品种均表现出叶片伸长叶部分的ABA含量相对较高。

英文摘要：

To better understand the relationship between cold resistance and ABA content in winter rapeseed （ Brassica rapa L . ） , the changes of ABA was measured using 2 ultrastrong cold - resistant cultivars （ Longyou 6 and Longyou 7） and 2 weak - resistant cultivars （Tianyou 2 and Tianyou 4）. Results showed that except Tianyou 4, ABA content increased gradually with the temperature before winter. Ultrastrong cold - resistant cultivars （Longyou 6 and Longyou 7 ） increased earlier than weak - resistant cultivars Tianyou 2. Correlation analysis indica-ted that wintering rate had greater correlation with ABA content of root than that of leaf. The ABA content of elon-gation part of leaf was higher than other parts in the mean time.