Plastid Transformation in Poplar: A Model for Perennial Trees

Poplar (Populus) is an important forest tree and considered model for perennial trees. Here we describe a method for poplar plastid transformation, which involves preparation of explants, vector construction, biolistic bombardment, regeneration and selection of transplastomic poplar plants. The young leaves of 4-week-old poplar plants are used for biolistic bombardment and aadA gene as selectable marker. Homoplasmic transplastomic lines are obtained after regeneration and several rounds of selection with spectinomycin over 10 months. Homoplasmy is further confirmed by Southern blot. The establishment of a plastid transformation system for Populus is likely to make a significant contribution to tree genetic improvement.