Increase of root induction in Pinus nigra explants using agrobacteria.

Wounding of explanted Pinus nigra primary explants followed by infection with Agrobacterium rhizogenes wild strains 8196, 15834, or with the pRiA4abc transconjugant strain of A. tumefaciens (C58 chromosomal background) resulted in adventitious root induction. Roots were formed in 60-97% of explants (1-3 roots/explant) but without a hairy root phenotype.