两种优良巴西杂交桉树的组织培养和快速繁殖

本研究以巴西尾巨桉和巨赤桉两种优良杂交桉树的带芽茎段为外植体进行离体培养和快速繁殖研究.结果表明:尾巨桉和巨赤桉再生芽诱导的最佳培养基为改良MS+6-BA 0.5 mg·L-1+NAA 0.2 mg·L-1,继代增殖的最适培养基为改良MS+6-BA 0.5 mg·L-1+NAA 0.15 mg·L-1.芽诱导和继代增殖中6-BA的浓度对两种杂交桉树有显著影响.生根培养中,尾巨桉和巨赤桉生根情况差异显著,尾巨桉茎芽最适生根培养基为1/2MS+NAA0.2 mg·L-1+IBA 1.0 mg·L-1,巨赤桉茎芽最适生根培养基为1/2MS+NAA 0.15 mg·L-1+IBA 1.0 mg·L-1.两种杂交桉树组织培养体系的建立,为桉树良种选育和遗传转化体系的研究提供技术参考.

Rapid Propagation of Two Brazilian Eucalypt Hybrids by Tissue Culture

Stem-segments taken from hybrid clones of Eucalyptus urophylla × E. grandis and E. grandis × E. camaldulensis derived from Brazilian breeding programs were used as explants for clonal propagation via tissue culture. The results showed that the optimal tissue culture medium for inducing multiple buds on stem tissues of these two eucalypt hybrids was improved MS + 6-BA 0.5 mg·L-1 + NAA 0.2 mg·L-1. The appropriate medium for adventitious bud multiplication was improved MS + 6-BA0.5 mg·L-1 + NAA0.15 mg·L-1. The concentration of 6-BA had significant effects on bud induction and multiplication of both hybrid clones. For development of roots in vitro, there were significant differences between the two hybrids, with the optimal rooting medium for E. urophylla × E. grandis being ?MS + NAA 0.2 mg·L-1 + IBA 1.0 mg·L-1, and that for E. grandis × E. camaldulensis being ?MS + NAA 0.15 mg·L-1 + IBA1.0 mg·L-1. Development of the optimal tissue culture techniques for the two Brazilian eucalypt hybrids provide a technical reference for future research including propagation of superior varieties and use of these varieties in genetic transformation systems.