不同高温胁迫条件下的坛紫菜中植物激素分析

The profiling of eleven phytohormones in Pyropia haitanensis under different high-temperature environments

摘要:

为了研究高温胁迫条件下内源性植物激素的变化趋势与坛紫菜在高温耐受性之间的相互关系，实验以在宁波象山采集的“浙东1号”坛紫菜叶状体为样品，以液相色—谱质谱联用的选择离子模式作为分析手段，系统地分析了高温胁迫条件下，坛紫菜中11种植物激素含量的变化。结果显示，在高温胁迫环境中共检测出7种植物激素，分别为异戊烯腺苷、异戊烯腺嘌呤、反式玉米素核苷、吲哚乙酸、茉莉酸甲酯、水杨酸和茉莉酸。在20、25、28和35°C下，茉莉酸和茉莉酸甲酯的含量随着刺激温度的上升而升高；吲哚乙酸、反式玉米素核苷、异戊烯腺苷和异戊烯腺嘌呤在高温组中的含量要明显低于对照组，呈现下降的趋势。以28°C作为胁迫温度，在不同胁迫时间下，吲哚乙酸、反式玉米素核苷、异戊烯腺苷和异戊烯腺嘌呤的含量随着胁迫时间的延长而降低；水杨酸和茉莉酸甲酯的含量随着胁迫时间的延长而上升；茉莉酸的含量先升高后下降。在恢复培养过程中，水杨酸、茉莉酸、吲哚乙酸和茉莉酸甲酯的含量均呈现下降、升高又下降的变化趋势，而反式玉米素核苷、异戊烯腺苷和异戊烯腺嘌呤的含量则随着恢复培养过程的进行而逐渐下降。高温胁迫下，坛紫菜在促进生长类激素和胁迫抑制类激素的共同调控下进行胁迫防御，维持自身生长。然而，坛紫菜的防御能力有限，且高温胁迫引起的藻体自损伤可能难以修复。

Abstract:

In order to investigate the relationship between the high temperature resistance and variation of phytohormones under high temperature environment, thalli of Pyropia haitanensis, Zhedong No. 1, collected from Xiangshan, Ningbo were used as experimental materials. And a method using high performance liquid chromatography coupled with mass spectrometry in selective reaction mode was developed, to analyse the variations of 11 kinds of phytohormones of P. haitanensis under different high temperature environments. The results showed that there were totally 7 kinds of phytohormones detected in the P. haitanensis under different high temperature environments, including N₆-(2-isopentenyl) adenosine, N₆-(2-isopentenyl)adenine, trans-zeatinriboside, indole-3-acetic acid, jasmonic acid, salicylic acid and methyl jasmonate. At the different high temperature 20, 25, 28 and 35°C, the contents of methyl jasmonate and jasmonic acid were increased as the stimulated temperature rose. While the contents of N₆-(2-isopentenyl) adenosine, N₆-(2-isopentenyl) adenine, trans-zeatinriboside and indole-3-acetic acid in high temperature group were lower than those of control group and showing the decreased trends. When at the different heat shock time, as the stimulated time increased, the contents of N₆-(2-isopentenyl) adenosine, N₆-(2-isopentenyl)adenine, trans-zeatinriboside, indole-3-acetic acid were reduced, while the contents of salicylic acid and methyl jasmonate were increased by comparing to that of control group. However, the content of jasmonic acid was increased, then decreased at 6h to that of control group. In the recovery procedure, the contents of indole-3-acetic acid, jasmonic acid, salicylic acid and methyl jasmonate were decreased, then increased, finally decreased again. For N₆-(2-isopentenyl) adenosine, N₆-(2-isopentenyl)adenine and trans-zeatinriboside, the contents of them were reduced gradually. Under high-temperature stress, the stress responses of P. haitanensis are co-regulated by positive growth regulator phytohormones and stress phytohormones to maintain its growth. However, the defense capacity of P. haitanensis is limited and it might be difficult for algae to repair its damage caused by high-temperature stress.