Onion yellow dwarf virus (OYDV) is a plant virus in the genus Potyvirus that has been identified worldwide and mainly infects species of Allium such as onion, garlic, and leek.[1][2][3][4] The virus causes mild to severe leaf malformation, and bulb reduction up to sixty percent has been observed in garlic.[5]
Genome
The full genome of OYDV is around 10,538 nucleotides long and encodes a polyprotein of 3,403 amino acids. Its P3 gene is longer than those of other known Potyviruses.[6]
OYDV is the first potyvirus found which has natural deletion mutants lacking the N-terminal region of helper-component proteinase (HC-Pro). The mutant isolates are common. Garlic plants grown commercially are generally co-infected with both the normal and attenuated isolates.[7]RNA silencing suppressor activities in isolates, which lack the long stretch of the N-terminal amino acids (~ 100 residues) in their HC-Pro gene, are observed to be low.[8]
Transmission
Isolates with complete HC-Pro sequences were non-persistently transmitted by aphids on their own, while the isolates with short HC-Pros (OYDV-S) were only aphid transmissible when they were co-infected with leek yellow stripe virus (LYSV), another potyvirus that mostly infects Allium spp. LYSV HC-Pro was assumed to interlink both LYSV and OYDV-S with the aphid stylet.[9] OYDV is not transmitted by dodder.[10]
References
^Ward, L. I.; Perez-Egusquiza, Z.; Fletcher, J. D.; Clover, G. R. G. (2009). "A survey of viral diseases of Allium crops in New Zealand". Australasian Plant Pathology. 38 (5): 533. Bibcode:2009AuPP...38..533W. doi:10.1071/AP09039. S2CID39328059.
^Santosa, Adyatma Irawan; Ertunc, Filiz (19 June 2020). "Identification, molecular detection and phylogenetic analysis of four viruses infecting Allium cepa in Ankara Province, Turkey". Journal of Plant Diseases and Protection. 127 (4): 561–569. doi:10.1007/s41348-020-00347-5. S2CID225488130.
^Lot, Harve; Chovelon, Véronique; Souche, Sylvie; Delecolle, Brigitte (2007). "Effects of Onion Yellow Dwarf and Leek Yellow Stripe Viruses on Symptomatology and Yield Loss of Three French Garlic Cultivars". Plant Disease. 82 (12): 1381–1385. doi:10.1094/PDIS.1998.82.12.1381. ISSN0191-2917. PMID30845474.
^Takaki, F.; Sano, T.; Yamashita, K. (3 July 2006). "The complete nucleotide sequence of attenuated onion yellow dwarf virus: a natural potyvirus deletion mutant lacking the N-terminal 92 amino acids of HC-Pro". Archives of Virology. 151 (7): 1439–1445. doi:10.1007/s00705-005-0716-5. PMID16463124. S2CID35484265.
^Kim, Hangil; Aoki, Nana; Takahashi, Haruna; Yoshida, Naoto; Shimura, Hanako; Masuta, Chikara (14 May 2020). "Reduced RNA silencing suppressor activity of onion yellow dwarf virus HC-Pro with N-terminal deletion may be complemented in mixed infection with another potyvirus in garlic". Journal of General Plant Pathology. 86 (4): 300–309. Bibcode:2020JGPP...86..300K. doi:10.1007/s10327-020-00926-2. S2CID218624707.
^Jayasinghe, Wikum H.; Kim, Hangil; Sasaki, June; Masuta, Chikara (7 March 2021). "Aphid transmissibility of onion yellow dwarf virus isolates with an N-terminal truncated HC-Pro is aided by leek yellow stripe virus". Journal of General Plant Pathology. 87 (3): 178–183. Bibcode:2021JGPP...87..178J. doi:10.1007/s10327-021-00986-y. S2CID233782267.
