Bacteria associated with vascular wilt of poplar

In 2017, the 560-ha area of hybrid
poplar plantation in northern Poland showed symptoms of
tree decline. Leaves appeared smaller, turned yellow-brown, and were shed
prematurely. Twigs and smaller branches died. Bark was sunken and
discolored, often loosened and split. Trunks decayed from the base. Phloem and xylem
showed brown necrosis. Ten per cent of trees died in 1-2 months. None of these
symptoms was typical for known poplar diseases. Bacteria in soil and the necrotic base of poplar trunk were analysed with
Illumina sequencing. The 16S rDNA was amplified with bacteria-specific primers: 16S-F 5' CAGCCTACGGGNGGCWGCAG, 16S-R 5'
ACAGGACTACHVGGGTATCTAATCC (Klindworth et al. 2013).