悬铃木下胚轴及叶片再生不定芽的影响因素分析

Factors Affecting Shoot Regeneration from Leaf and Hypocotyl Explants of Platanus acerifolia Willd.

以悬铃木的下胚轴和离体叶片为材料,研究了基因型、植物生长调节剂、光照条件、外植体部位等因素对其不定芽分化的影响。结果表明:1)6-BA与IBA的浓度比对下胚轴不定芽的分化影响较大,以6-BA∶IBA小于20∶1较为合适;而叶片的不定芽再生受基因型的影响显著,在4种供试材料中,PH2的再生能力最强,但0.1～1.0mg·L-1TDZ不利于其不定芽再生。2)黑暗培养对下胚轴的不定芽分化有一定的促进作用,但不利于叶片的不定芽再生,50～100lx的弱光有利于叶片的不定芽分化。3)不同部位的下胚轴切段及叶片的再生能力差异显著,其中靠近子叶的下胚轴切段和试管苗顶端的2枚叶片再生能力较强。此外,刻伤叶片的再生效果明显优于叶片切块,说明悬铃木的叶片与下胚轴的离体培养存在明显的生物全息现象。

Effects of different genotypes,PGRs,illumination conditions and position of explants on adventitious shoot regeneration from hypocotyl and/or leaf of Platanus acerifolia were investigated.The results indicated that the ratio of 6-BA to IBA in the medium influenced shoot regeneration of hypocotyl segments and 6-BA：IBA〈20：1 gave a better effect;Shoot regeneration from leaf explants was significantly different among four different genotypes investigated,with the highest regeneration rate obtained for leaf explants of genotype PH2,and TDZ was less effective than 6-BA to induce shoot regeneration from PH2 leaves.Maintaining the cultures in darkness for the first month promoted shoot regeneration of hypocotyl explants to some extent,but leaves incubated in darkness regenerated less shoots evidently;Light intensity of 50-100 lx was favorable to shoot regeneration.Significant differences of regeneration capability existed among different sections of hypocotyl and position of leaves,and the hypocotyl section adjacent to the cotyledons and the uppermost two leaves of the shoots showed better regeneration capability than the lower sections and leaves.Furthermore,shoot regeneration of the intact leaves wounded by three cuts was more efficient than that of severed leaf segments,indicating that the ECIWO/holographic phenomenon existed during in vitro culture of hypocotyls and leaves of P.acerifolia.