Abstract
A novel potyvirus we call Gazar virus Y (GVY) was isolated from diseased carrot plants in Egypt. It produced symptoms similar to those caused by carrot virus Y. Its particles were visualized in leaf extracts using negative stain, and leaf tissues from carrot plants infected with GVY had many ultra-structural differences from healthy ones. Chemical analyses of healthy and infected carrot roots showed that carrot roots infected with GVY had increased dry weight and decreased moisture, total ash, total carbohydrates, total fibres, vitamin C, beta-carotene, vitamin A and the minerals of K, Mg, Na, P and Ca compared to the healthy carrot roots. Molecular methods, including reverse transcription-polymerase chain reaction (RT-PCR), were used to amplify a 335 bp cDNA fragment transcribed from infected plant extracts using degenerate oligonucleotide primers specific for potyviruses. The amplified cDNA was cloned into pGEMA (R)-T Easy vector, and transformed into Escherichia coli (E. coli) strain DH5 alpha . The recombinant inserts were sequenced. The nucleotide sequence (GenBank Accession Code GQ148776) was matched against viral nucleotide sequences in the GenBank database. It is most closely related to viruses of the celery mosaic virus group of potyviruses, but is distinct from all and represents a sister lineage to all others described so far.