《植物生理学报》 2015, 51(6): 935-940

滇杨倒置插穗的生长素极性运输

李佳蔓^1,2, 员涛^1,2, 王军民^2,3, 郑元^2,3, 周安佩^1,2, 纵丹^1,2, 何承忠^1,2,3,*

西南林业大学¹云南省高校林木遗传改良与繁育重点实验室, ²西南地区生物多样性保育国家林业局重点实验室, ³西南山地森林资源保育与利用省部共建教育部重点实验室, 昆明650224

通信作者：何承忠；E-mail: hcz70@163.com；Tel: 0871-63863213

摘　要：

生长素是唯一具有极性运输的内源激素, 在植株生长发育过程中发挥着重要的调控作用。为探讨倒置插穗在生根发芽过程中生长素的极性运输规律, 以滇杨1年生根萌苗主干制作插穗, 分别正向放置和倒向放置后进行水培, 采用高效液相色谱法(HPLC)测定正置、倒置插穗不同部位树皮与侧芽内生长素(IAA)和脱落酸(ABA)含量的动态变化。结果表明, 不同时期滇杨正置、倒置插穗树皮和侧芽内IAA和ABA总含量的动态变化规律存在差异, 极性对倒置插穗的生理生化活性有一定的影响。滇杨正置插穗树皮和侧芽内IAA的运输符合极性运输规律。倒置插穗分别在21 d和28 d之前, 其树皮和侧芽内IAA的运输符合极性运输规律, 即从形态学上端(插穗的下端)向形态学下端(插穗的上端)运输; 之后, 倒置插穗内重新建立了IAA的运输方向, 即从形态学下端(插穗的上端)向形态学上端(插穗的下端)运输。正置与倒置插穗不同部位树皮和侧芽内ABA的含量从上到下依次递增, 运输规律遵循向重力性。研究结果初步表明: 滇杨倒置插穗内IAA的极性运输可能会发生逆转。

关键词：滇杨; 正置插穗; 倒置插穗; 生长素极性运输

收稿：2015-02-09   修定：2015-05-07

资助：国家林业公益性行业科研专项(201104076)、国家自然科学基金(31360184)、云南省中青年学术与技术带头人后备人才培养基金(2012HB021)和西南林业大学大学生创新基金(C14114)。

The Polarity of Auxin Transport in Inverted Cuttings of Populus yunnanensis

LI Jia-Man^1,2, YUN Tao^1,2, WANG Jun-Min^2,3, ZHENG Yuan^2,3, ZHOU An-Pei^1,2, ZONG Dan^1,2, HE Cheng-Zhong^1,2,3,*

¹Key Laboratory for Forest Genetic and Tree Improvement & Propagation in Universities of Yunnan Province, ²Key Laboratory of Biodiversity Conservation in Southwest China, State Forestry Administration, ³Key Laboratory for Forest Resources Conservation and Use in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming 650224, China

Corresponding author: HE Cheng-Zhong; E-mail: hcz70@163.com; Tel: 0871-63863213

Abstract:

Polar transport within plant tissues is unique to auxin, and it plays an important role to regulate plant growth and development. In order to investigate the polar auxin transport regularity in inverted cutting of Populus yunnanensis for the duration of rooting and shooting, cuttings made of one-year-old main stem of P. yunnanensis rootlings, upright and inverted cuttings cultured in water, high performance liquid chromatography (HPLC) was used to measure the dynamic changes of IAA and ABA contents in different parts of bark and lateral buds of upright and inverted cuttings. The results showed that differences existed in amount contents of IAA and ABA in bark and lateral buds between upright cuttings and inverted cuttings, and the polarity made certain effects on physiological and biochemical activity of inverted cuttings. Dynamic changes of IAA contents in different parts of bark and lateral buds indicated that polar auxin transport persisted in the original basipetal polarity in the upright cuttings in whole culturing period. On inverted cuttings, auxin transport obeyed the original basipetal polarity in the early 21 d (in bark) or 28 d (in lateral buds). Since then, a reversal of polarity of auxin transport was formed in inverted cuttings, and IAA could be transported from original morphological base to apex. The trend of ABA contents in different parts of bark and lateral buds of upright cuttings or inverted cuttings was increased successively from superior to inferior; the regulation of ABA transport obeyed the gravitation. All of the results in this study illustrated that polar auxin transport could be reestablished a polarly inverted direction in inverted cuttings of P. yunnanensis.

Key words: Populus yunnanensis; upright cutting; inverted cutting; polar auxin transport