【摘要】 以南京椴嫩枝插穗为研究对象,采用1 000 mg·kg-1 IBA粉剂处理插穗基部,对扦插生根过程中插穗皮部生长素IAA、玉米素核苷ZR、赤霉素GA3、脱落酸ABA含量以及IAA/ABA和IAA/ZR比值进行动态测定,探究嫩枝扦插生根过程中植物激素变化特点及其对生根的影响。结果表明:1)IBA处理可以显著促进南京椴嫩枝插穗生根,生根率接近67%;其生根过程可划分为愈伤组织形成期、根原基诱导期、不定根形成期和不定根生长期,各自对应时间约为10 d。2)IBA处理可以提高嫩枝插穗中IAA含量,IAA对于根原基的诱导和不定根的发生具有较为直接的影响作用,其含量升高有利于生根;GA3含量增加有利于根原基形成,而低水平GA3则更有利于不定根的生长;ABA和ZR含量升高不利于插穗生根,对于根原基的诱导和不定根的发生具有抑制作用;IAA、ABA在插穗根原基诱导和不定根形成过程中具有相互协调作用,IAA/ABA可作为衡量南京椴嫩枝扦插生根能力的指标。3)外源IBA处理可以促进插穗内IAA含量升高,调节ABA、ZR、GA3含量降低,促使IAA/ABA在诱导生根期快速增大,通过相关激素的调控,使插穗向有利于促进生根的生理状态转变。更多还原

【Abstract】 In order to explore the changing characteristics and effects of plant hormones on rooting, the soft wood cutting of Tilia miqueliana was treated with 1 000 mg·kg-1 IBA powder, and the content changes of IAA, ZR, GA3, ABA, and the ratio changes of IAA/ABA, IAA/ZR in the cuuting skin were measured. The results show that 1) IBA treatment could obviously promote the rooting of soft wood cutting of T. miqueliana and the rooting rate was about 67%; the rooting process could be divided into formative period of callus,induction period of root primordium, formative period of adventitious root and the growth period of adventitious root, and each period lasted for about 10 days. 2) IBA treatment could increase the IAA content which had directly in?uences of inducting root primordium and forming adventitious root, and the increase of IAA content was conductive to rooting. The increase of GA3 content was conductive to generate root primordium and the low level of GA3 was more favorable to the growth of adventitious root; the increase of ABA and ZA content was against to the rooting of cutting and restrained the induction of root primordium and the generation of adventitious root. There was an inter-coordination function between IAA and ABA on the induction period of root primordium and the formative period of adventitious root, and the rate of IAA/ABA could be used as an index to measure the rooting ability of soft wood cutting of T.miqueliana. 3) Exogenous IBA could promote the increase of IAA content, the decrease of ABA, ZR, GA3 content and the fast increase of IAA/ABA on the induction period of rooting, which made the cutting towards to a physiological state for rooting by adjusting relative hormones.更多还原