水分胁迫下ABA由蚕豆根向地上部的运输及其在叶片组织中的分布

蚕豆根装载的３Ｈ－ＡＢＡ可经５．６ｃｍ／ｍｉｎ以上的速率向冠部运输。短时间内（５ｍｉｎ）根运来的ＡＢＡ主要分布在有大量气孔密布的下表皮，但长时间内（３ｈ）则主要分布在对内组织中。抑制蒸腾可降低ＡＢＡ向叶片中的运输积累。光镜放射自显影术显示，根运来的ＡＢＡ可有效地在表皮细胞及保卫细胞的质外体积累。３Ｈ－ＡＢＡ由根向地上部快速运输及其在作用部位的有效积累，说明水分胁迫下蚕豆根部可以通过ＡＢＡ信号的传递控制气孔的行为。

The Transport of ABA from Root to Shoot and Its Distribution in Response to Water Stress in Vicia faba L.

H-ABA loaded in roots of Vicia faba L. could be transported to shoot ata speed of 5.6 cm/min or higher in arelatively short period of 5 min (Fig.1). ABA transported from roots wasdistributed mainly in the epidermis(Fig. 2). However, after 3 h, it wasmainly distributed in mesophyll cells(Fig. 2) When the transport was inhibited by covering the leaf surface withParafilm, the transport and accumulation of ABA in leaves declined substantially (Fig. 3). The results of autoradiography showed that ABA transportedfrom roots to shoots could be distributied in the apoplast of guard cells andepidermal cells (Fig. 4). The rapidtransport of ABA from root to shootand its accumulation in apoplast ofguard cells indicated that stomatalmovement could be controled by ABAcommunication from root to shoot in response to water stress in Vicia faba L.