Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

First report of citrus viroids infecting Persian (Tahiti) lime in Greece.

Abstract

In the spring of 2018, in a small lime (Citrus latifolia) orchard of 40 5-year-old trees (grafted on C. aurantium), yellow fruit sectoring and shoot bark cracking symptoms were observed in six trees in Greece. A total of eight samples, six symptomatic and two asymptomatic trees, were collected. All of them were tested for the presence of the most prevalent citrus viroid, Citrus exocortis viroid (CEVd) by reverse transcription-polymerase reaction (RT-PCR), amplifying the entire viroid genome. The results revealed the presence of CEVd in all the symptomatic plants, whereas the viroid was not detected in the asymptomatic trees. The de novo assembly of these reads and the BLASTN analysis of the produced contigs resulted in the confirmation of presence of CEVd in addition to the identification of Hop stunt viroid (HSVd), Citrus bark cracking viroid (CBCVd), and Citrus dwarfing viroid (CDVd). A recently discovered virus was also detected, which will be described elsewhere. The complete viroid genomes of 370, 302, 286, and 291 nucleotides in length for CEVd, HSVd, CBCVd, and CDVd, respectively, were reconstructed, and the genomes shared 99% (CEVd, CDVd) and 100% (HSVd, CBCVd) nucleotide identity with other available sequences of isolates from different countries This is thought to be the first report of citrus viroids infecting lime in Greece associated with bark cracking symptoms.