花生开花下针期^(14)C-生长素的运输与分布

Transportation and Distribution of ^(14)C-Labelled Auxin in the Pegging Stage of Peanut (Arachis hypogaea L.)

为研究花生开花下针期生长素在植株中的运输与分布规律,以‘中花4号’花生为试验材料,以14C-IAA为示踪物,对花生不同部位中14C-IAA的分布进行放射自显影定位分析,并利用液体闪烁计数仪进行定量检测。结果表明:涂布于花生主茎顶叶的14C-IAA在处理48h后向根和茎中的转运量增加,向下运输的速率约为5mm·h-1。通过浸泡处理进入根系的14C-IAA具有向顶传导的能力,但在根系中的滞留量较高,处理24h时14C-IAA向地上部分转运的能力较强。涂布于果针着生部位上方茎段的14C-IAA可同时向上、下两个方向运输,且处理24h时运输能力较强。带有果针的花在涂布处理72h后其14C-IAA主要向下运输;而尚未形成果针的花涂布处理后其14C-IAA运输至不同部位的含量为:叶>茎>根。

In order to reveal the transportation and distribution of ^14C-labelled auxin in different parts at the pegging stage of peanut, ‘Zhonghua 4＇ was used as the experimental material by locally applying ^14C-IAA on top leaves, roots, flowers and stem portions below where pegs were originated, the autoradiographs were analysed and the radioactivity in the different parts was determined by using a liquid scintillation counter. The results showed that the ^14C-IAA contents in roots and stems were higher than in leaves at 48 h after the treatment, and the transport rate was approximately 5 mm·h^-1 from top leaves to downwards of stems when top leaves were treated. In case of root treatment, ^14C-IAA had a transportation trend upwards. The accumulation of ^14C-IAA in roots was higher than in other parts, moreover the upwards transportation ability of lgC-IAA was stronger at 24 h after the treatment. Whereas ^14C-IAA applied in the stem portions transported both upwards and downwards simultaneously, and ^14C-IAA content was found to be high in roots, stems and leaves after treated 24 h. The transportation of ^14C-IAA from flowers with pegs was found mainly downwards after treated for 72 h. However the highest content of ^14C-IAA was found in leaves followed by stems and the lowest was in roots in case of ^14C-IAA transportation from flowers without pegs.