Nucleotide sequences of citrus viroids CVd-IIIa and CVd-IV obtained from dwarfed Meyer lemon trees grafted on sour orange

Citrus viroids CVd-IIIa and CVd-IV were found in naturally dwarfed Meyer limon (Citrus lemon (L.) Burm. f.) trees grafted on sour orange in the east Mediterranean region of Turkey. The occurence of CVd-IIIa and CVd-IV was interesting since no dwarfing agents are known for trees grafted on sour orange. Nucleotide sequencing of CVd-IIIa showed that it was 297 nucleotides in length and CVd-IV was found 284 nucleotides in length. Sequences of these viroids were essentially the same as those described in literature. No viroids were detected in the normal sized Meyer lemon trees in the same orchard. The possibility that Meyer lemon or the combination of Meyer lemon on sour orange rootstock is sensitive to this viroid is discussed