New genetically distinct phytoplasmas and insect carriers associated with pine tree disease revealed by a survey in the Curonian Spit, Lithuania

Researchers have identified three new genetically distinct phytoplasma subgroups associated with pine tree disease on the Curonian Spit, Lithuania. These subgroups—16SrXXI-C, 16SrXXI-D, and 16SrXXI-E—were discovered through a survey of phloem-feeding insects, primarily aphids, collected from diseased pine trees between 2016 and 2019. The study used semi-nested PCR and sequence analysis to detect phytoplasmas in Scots pine aphids (Cinara pini) and waxy grey pine needle aphids (Cinara pineti), revealing that the dominant strains matched those found in diseased trees, primarily 16SrXXI-A variants. No known phytoplasma vectors were identified among the 98.62% aphid population sampled. Further transmission trials are planned to elucidate the epidemiology and potential vectors of pine phytoplasma diseases, offering insights for disease management in this UNESCO World Heritage Site.

Ivanauskas, A., Valiunas, D., Rimsaite, J., Danilov, J., Sneideris, D., Zizyte-Eidetiene, M., & Wei, W. (2022). New genetically distinct phytoplasmas and insect carriers associated with pine tree disease revealed by a survey in the Curonian Spit, Lithuania. Canadian Journal of Forest Research, 52(2), 201–208. https://doi.org/10.1139/cjfr-2021-0152