International Institute for Science, Technology and Education, cilt.13, sa.18, ss.23-30, 2023 (Hakemli Dergi)
Foaming was observed in mandarin and orange species that were grafted on rootstocks trifoliata (Poncirus
trifoliata) hybrids and was investigated in terms of phytopathological causes in the Cukurova region, where 80%
of Turkey's citrus production takes place. Citrus exocortis viroid (CEVd) and citrus cachexia viroid (CCaVd)
agents were screened by RT-PCR method by taking samples from different citrus rootstocks and cultivars
showing foamy bark symptoms. It was determined that 17 of the 49 isolates were infected with CEVd and 14 of
them were infected with CCaVd. There are 4 trees infected by both viroid agents at the same time. Based on a
blast analysis, it was found that the reference genomes for CEVd and CCaVd in the NCBI GenBank had 95-
100%. To check on the presence of bacterial and fungal agents, isolates were created from the foamy bark tissue
of citrus trees. Lasiodiplodia theobromae, Ilyonectria liriodendri, Fusarium pseudonygamai, Alternaria
alternata, and Streptomyces spp. were found as a result of the isolations. Analysis of soil samples taken from
citrus plantations that had indications of foamy bark revealed a high calcareous soil structure with a pH above
7.5.