執行成果摘要
This 4-year research project is proposed to develop gene-stacking technology for the breeding of new Eucalyptus varieties in which multiple genetic characteristics are improved to meet the demand in industry. Preservation technology is also proposed to develop for the establishment of mutant bank containing varied transgenic lines of Eucalyptus that will bring the molecular breeding into the new research area of functional genomics. In this second year's project, gene stacking by sequential transformation will be developed to raise transgenic E. camaldulensis plants with the antisense Pt4CL1 and the sense CAld5H transgenes. The transgenic E. camaldulensis plants previously transformedwith the sense CAld5H transgenes will be sequentially transferred with recombinant SiRNA of the CAD gene to produced transgenic callus or shoots with double transgenes. In co-transformation, transgenic Eucalyptus plants with the antisense Euc4CL1 and/or the sense CALd5H transgene will be produced. The transgenic E. camaldulensis plants previously transformed with the sense CAld5H transgenes will be selected and transferred with recombinant SiRNA of the CAD gene to produce transgenic callus or shoots with multiple transgenes. In addition to these, another 2 cellulose synthase (CesA) genes will be cloned from E. camaldulensis readily for the further co-transformation work in the following year. In controlled pollination of gene stacking, transgenic seedlings with C4H and GUS transgenes derived from pollination between transgenic E. grandis x E. urophylla and E. camaldulensis will be raised. Transgenic Eucalyptus previously transformed with either the antisense Euc4CL1 or the sense CAld5H transgene will be induced to flower for making more controlled pollinations. For rapidly measuring monomeric lignol of transgenic wood, an analytical technique by using pyrolyzer coupled with GC-MS will be developed. The low-temperature preservation technique developed in the last year's project will be used to preserve varied transgenic shoots produced from this or previous projects.