Affiliation:
1. College of Plant Protection, China Agricultural University, Haidian District, Beijing 100193, China
Abstract
In the current study, a novel strain of Fusarium oxysporum alternavirus 1 (FoAV1) was identified from the Fusarium oxysporum f. sp. melonis (FOM) strain T-BJ17 and was designated as Fusarium oxysporum alternavirus 1-FOM (FoAV1-FOM). Its genome consists of four dsRNA segments of 3515 bp (dsRNA1), 2663 bp (dsRNA2), 2368 bp (dsRNA3), and 1776 bp (dsRNA4) in length. Open reading frame 1 (ORF1) in dsRNA1 was found to encode a putative RNA-dependent RNA polymerase (RdRp), whose amino acid sequence was 99.02% identical to that of its counterpart in FoAV1; while ORF2 in dsRNA2, ORF3 in dsRNA3, and ORF4 in dsRNA4 were all found to encode hypothetical proteins. Strain T-BJ17-VF, which was verified to FoAV1-FOM-free, was obtained using single-hyphal-tip culture combined with high-temperature treatment to eliminate FoAV1-FOM from strain T-BJ17. The colony growth rate, ability to produce spores, and virulence of strain T-BJ17 were significantly lower than those of T-BJ17-VF, while the dry weight of the mycelial biomass and the sensitivity to difenoconazole and pydiflumetofen of strain T-BJ17 were greater than those of T-BJ17-VF. FoAV1-FOM was capable of 100% vertical transmission via spores. To our knowledge, this is the first time that an alternavirus has infected FOM, and this is the first report of hypovirulence and increased sensitivity to difenoconazole and pydiflumetofen induced by FoAV1-FOM infection in FOM.
Funder
Beijing Innovation Consortium of Special Crops Research System
Reference59 articles.
1. Defence response in plants and animals against a common fungal pathogen, Fusarium oxysporum;Nag;Curr. Res. Microb. Sci.,2022
2. Complete genome sequence of a novel mitovirus from the phytopathogenic fungus Fusarium oxysporum;Wang;Arch. Virol.,2021
3. Wang, J., Li, C.J., Song, P.Y., Qiu, R., Song, R.F., Li, X.J., Ni, Y.X., Zhao, H., Liu, H.Y., and Li, S.J. (2022). Molecular and biological characterization of the first mymonavirus identified in Fusarium oxysporum. Front. Microbiol., 13.
4. Fusarium oxysporum f. sp. dianthi virus 1 accumulation is correlated with changes in virulence and other phenotypic traits of its fungal host;Phytopathology,2018
5. Horizontal and vertical transmission of the hypovirulence-associated mycovirus Fusarium oxysporum f. sp. dianthi virus 1;Eur. J. Plant Pathol.,2019