Agrobacterium-mediated transformation of dormant lateral buds in poplar trees reveals developmental patterns in secondary stem tissues.

In an attempt to devise a method for the rapid creation of somatic transgenic wood sectors of sufficient size that would allow us to detect and analyse altered wood characteristics within them, we have explored the manual wounding and subsequent infection with Agrobacterium of dormant lateral buds in poplar. Following treatment and transformation with a 35S-GUS construct, frequent stable transformation was found in the form of distinct and specific GUS staining patterns in the outer cortex, cambial region (including primary and secondary xylem and phloem) and pith. Sector frequency and size were consistent with anatomical features of dormant lateral buds at the time of manual wounding and Agrobacterium-infection. The suitability of somatic sector analysis for functional genomic studies as well as for studies investigating pattern formation and the developmental fate of various cell-types within poplar stems is discussed.