“艾西丝”南瓜诱导生根过程中过氧化物酶活性及同工酶的研究

STUDIES ON PEROXIDASE ACTIVITY AND ISOPEROXIDASE IN CUCURBITA MOSCHATA DURING ROOTING INDUCTION

以“艾西丝”南瓜组培苗为材料，研究其在诱导不定根形成过程中过氧化物酶活性及同工酶谱的变化。结果表明，当南瓜无根苗从含有较高浓度的ＢＡ培养基转入１／２ＭＳ培养基后，可诱导无根苗茎基部不定根生成，一般在转入生根培养基第３ｄ开始生根，至第６ｄ生根率达７０％以上。在此期间，南瓜茎内过氧化物酶活性由低增高，即在不定根形成之前，过氧化物酶活性处在较低水平，而当不定根形成时，过氧化物酶活性迅速升高，以后一直维持在较高水平；同时过氧化物酶的同工酶谱也发生了变化，在不定根形成前酶带为３条，Ｒｆ分别为０．４４，０．５８，０．６６。而在不定根开始形成时及形成以后，酶带增至４条，即在阴极区增加了Ｒｆ为０．３５的谱带。这反映出在南瓜不定根形成各个阶段有不同同工酶在起作用。

The changes of peroxidase activity and isoperoxidase were studied during rooting induction of the tissue culture shoots of Cucurbita moschata .The results indicated that the adventitious root could be induced when rootless shoots were inoculated from MS medium supplemented with a higher concentration of BA to 1/2 MS medium with no hormones.The shoots began to root after three days,and the rate of rooting was over 70% after 6 days on rooting medium.The peroxidase activity was lower before formation of roots and rapidly increased in the course of forming root,and kept a higher level.There were three isoperoxidase bands in rootless shoots which grew on rooting medium before the adventitious roots forming,and the isozymes emerged a new bands in cathode when the root formation.This showed that different isoperoxidase took effect in different periods of adventitious root forming.