The book contains abstracts of talks and posters presented by participants of the “International Conference on Viroids and Viroid-Like RNAs”. The conference was held on June 25–28, 2015, in Ceské Budejovice, Czech Republic. Viroids are the smallest infectious particles known: they consist of a single non-coding circular RNA molecule, ranging in size from about 250 to 400 nucleotides. They function as a minimal parasite replicating autonomously in the plant host’s cells and promoting specific diseases leading to significant losses in the yield of some important crops. The abstracts focus on three important aspects of viroid research: viroid secondary and tertiary structure and structural dynamics, which are critical for their replication cycle exploiting the host machinery; transcriptional and post-transcriptional gene silencing induced by viroids, which is thought to be leading to host’s symptoms; and viroid outbreaks as threats to crops and ornamental plants.
