干旱对苜蓿叶片葫芦巴碱含量和渗透调节能力的影响

Effects of drought on trigonelline content and osmotic adjustment in leaves of three alfalfa (Medicago sativa L.) varieties

以3个抗旱性不同的苜蓿品种(肇东、准葛尔和CW200)为研究材料,研究了干旱胁迫下苜蓿叶片葫芦巴碱含量的变化和渗透调节能力。结果表明:干旱胁迫下3个苜蓿品种叶片水势降低,脯氨酸含量增加,渗透调节能力(OA)提高。在干旱胁迫下,准葛尔和肇东两个品种叶片中葫芦巴碱含量明显增加,而CW200叶片中葫芦巴碱含量增加不明显;肇东和CW200在干旱4天后,准葛尔在干旱8天后,叶片中葫芦巴碱含量下降。因此,葫芦巴碱在轻度干旱下可能起到渗透调节物质的作用,严重干旱下该作用减弱。

Taking three alfalfa varieties Zhunger, Zhaodong and CW200 as test materials, this paper studied the changes of trigonelline content and osmotic adjustment under drought stress. The results showed that leaf water potential （ψw） decreased. Proline in leaves of three varieties was accumulated, and osmotic adjustment （OA） increased for 16 days. Trigonelline content in leaves of Zhunger and Zhaodong increased significantly within 8-day drought, but not significantly in leaves of CW200, trigonelline content in leaves of Zhaodong and CW200 after 4 - day drought and Zhunger after 8 - day drought declined. It was suggested that trigonelline increasing as the osmolyte could achieve osmotic adjust-merit significantly under moderate drought, but not significantly under severe drought.