摘要
为加快西南桦良种选育进程,解决实生苗造林分化大的问题,以西南桦萌生嫩芽为外植体,对西南桦组培快繁过程中母树年龄、细胞分裂素种类和浓度等因素对外植体诱导、增殖和生根的影响开展了研究。结果表明,外植体采集母树树龄与诱导率成反比,树龄越大成功率越低,0.5年的诱导率为90.5%,而25年仅为18.1%;在外植体诱导培养阶段,采用改良MS为基本培养基,添加低浓度的KT,有利于外植体的腋芽萌动与生长;在增殖培养阶段,采用改良MS+KT 0.25mg/L+IBA 0.25mg/L培养基,在确保有较高比例根系形成的前提下,促进腋芽萌发并生长能获得较高的增殖倍数;将具顶芽的西南桦小苗接种在改良MS+IBA 1.0mg/L的培养基上进行根系诱导最为有效,生根率达100%。研究结果将为西南桦无性系造林提供理论支持。
To accelerate breeding process of Betula alnoides and solve problem of large differentiation during the forestation with true seed plantlets of this species, this paper studied the effects of the age of mother trees, concen-trations and kinds of cytokinins on explants induction, propagation and roots induction. The results indicated that the induction rate of buds from shoot segments varied inversely with the age of the mother tree. In other words, the older the mother tree was, the less the buds induction rate was. For example, the buds induction rate of 0. 5amother trees was 90. 5% , but th e ra teo f 25a ones was 18. 1% only. At the stage of explants induction, the axil-lary buds,sprouting and elongation fitted well with modified MS media along with the low concentration of KT. At the stage of propagation, the modified media MS＋KT 0 . 25mgL＋IE〉A 0 . 2 5m gL wouldthe axillary buds,sprouting and extension based on the high proportion of roots formation. The effective medium was the modified medium MS＋IBA 1. 0mgL to culture the plantlets of B. alnoides as with apical buds to induce roots. And its root inducing rate was 100%. Al results above will provide theoretical supports to actualize the for-estation with B. alnoides clones.
作者
管朝旭
杨明志
曾德贤
方向京
GUAN Zhao-xu YANG Ming-zhi ZENG De-xian FANG Xiang-jing(Forestry Seed and Seedling Station of Yunnan province, Kunming Yunnan 650215, P. R. China)
出处
《西部林业科学》
CAS
2017年第3期76-81,88,共7页
Journal of West China Forestry Science
关键词
西南桦
组织培养
快速繁殖
Betula alnoides
tissue culture
rapid propagation
