菊苣高效不定芽直接发生及其植株再生

AN EFFICIENT PLANT REGENERATION SYSTEM VIA DIRECT ADVENTITIOUS BUD FORMATION IN CHICORY

本研究以菊苣无菌苗叶片为外植体，建立了高效不定芽直接发生及其植株再生体系。在附加不同浓度N-6-benzyladenine（6-BA）或与低浓度α-naphthaleneaceticacid（NAA）组合的MS培养基上，5～7d外植体表面不经过愈伤组织诱导阶段，直接形成不定芽。组织学观察表明，不定芽起源于叶片雏管束薄壁细胞，且其微管组织系统与叶片外植体内微管组织系统紧密相连。6-BA是不定芽直接发生所必需的，外植体的发育时期、取材部位和培养基蔗糖浓度对不定芽直接发生有重要影响。在附加2．0mg/L6-BA，0．5mg／LNAA，100mg／LVc，100mg／LVB1，300mg／L脯氨酸和40g／L蔗糖的MS培养基上，培养20d龄基部叶片15d时，不定芽直接发生频率最高为100％，每块外植体上产生的不定芽数量也最多，平均为36～38个。在1／2MS＋IBA0．5mg/L培养基上，再生苗诱导生根频率为97．58％，再生植株移栽于盆土中，100％存活且生长良好，未见形态异常。

An efficient plant regeneration system through direct adventitious bud formation is established using leaf segments of asepsis seedlings of chicory （ Cichorium intybus L. ）. After 5 - 7d of culture, adventitious buds appeared directly from explants without any intervening callus on Murashige and Skoog （MS） medium supplemented with different Concentrations of N-6-benzyladenine （BA） alone or together with 0.Smg/L α-naphthaleneacetic acid （NAA）. According to histological observations, adventitious buds were originated from thin wall cell of vascular bundle of the leafs, and the vascular bundle systems of adventitious buds are closely connected with that of leaf explant. 6-BA was necessary for direct adventitious bud formation. The frequency and number of adventitious bud formation were strongly influenced by the development stage of explants and sucrose concentration. After 15 days culture, the 100% frequency of bud formation as well as an average of 36～38 adventitious buds per explant were obtained on MS medium supplemented with 2.0mg/L 6-BA,0.Smg/L NAA, 100mg/L Vc, 100mg/L VB1, 300mg/L proline and 40 g/L sucrose using 20-day-old leaves. When transplanted and cultured for about 10d on the 1/2 MS medium added 0.5mg/L indole-3-butyric acid （IBA）, 97.58% rooting frequency was obtained. Planflets grew well and appeared normal with no mortality after transfer to soil.