Field sweet potato plants showing virus-like symptoms, as stunting, leaf distortion, mosaic and chlorosis, were collected in southwest Portugal and tested for the presence of four potyviruses, sweet potato virus C (SPVC), sweet potato virus 2 (SPV2), sweet potato feathery mottle virus (SPFMV), sweet potato virus G (SPVG), and the crinivirus sweet potato chlorotic stunt virus (SPCSV). DsRNA frac...

In sub-Saharan Africa, sweetpotato (Impomoea batatas L.) production is greatly constrained by sweetpotato virus disease (SPVD) complex. This study was conducted to assess the incidence of viruses in healthy-looking sweetpotato in Uganda and to optimise modern technologies for virus diagnosis. A collection of healthy-looking sweetpotato vines from central Uganda were serologically assayed for sw...

Potato virus Y is the most economically important potato viral pathogen. We aimed at unraveling the roles of small RNAs (sRNAs) in the complex immune signaling network controlling the establishment of tolerant response of potato cv. Désirée to the virus. We constructed a sRNA regulatory network connecting sRNAs and their targets to link sRNA level responses to physiological processes. We discov...

Different mutants of an infectious full-length clone (p35PPV-NAT) of Plum pox virus (PPV) were constructed: three mutants with mutations of the assembly motifs RQ and DF in the coat protein gene (CP) and two CP chimeras with exchanges in the CP core region of Zucchini yellow mosaic virus and Potato virus Y. The assembly mutants were restricted to single infected cells, whereas the PPV chimeras ...

18 Potato virus Y is the most economically important potato viral pathogen. We aimed at 19 unraveling the roles of small RNAs (sRNAs) in the complex immune signaling network 20 controlling the establishment of tolerant response of potato cv. Désirée to the virus. We 21 constructed a sRNA regulatory network connecting sRNAs and their targets to link sRNA 22 level responses to physiological proce...

The multifunctional helper component proteinase (HCpro) of potyviruses (genus Potyvirus; Potyviridae) shows self-interaction and interacts with other potyviral and host plant proteins. Host proteins that are pivotal to potyvirus infection include the eukaryotic translation initiation factor eIF4E and the isoform eIF(iso)4E, which interact with viral genome-linked protein (VPg). Here we show tha...

Risk-assessment studies of virus-resistant transgenic plants (VRTPs) focussing on recombination of a plant virus with a transgenic sequence of a different virus should include a comparison of recombination frequencies between viruses in double-infected non-transgenic plants with those observed in singly infected transgenic plants to estimate recombination incidence in VRTPs. In this study, the ...

The p24 protein, one of the three proteins implicated in local movement of potato virus X (PVX), was expressed in transgenic tobacco plants (Nicotiana tabacum Xanthi D8 NN). Plants with the highest level of p24 accumulation exhibited a stunted and slightly chlorotic phenotype. These transgenic plants facilitate the cell-to-cell movement of a mutant of PVX that contained a frameshift mutation in...

The ability of potato-derived major surface antigen of hepatitis B virus (P-HBsAg) to elicit antibody responses to different dosages of P-HBsAg ranging from 0.02 to 30 μg administered orally in mice was examined. All immunized groups produced specific serum IgG and fecal IgA antibodies against P-HBsAg, even at low levels (<5 μg), after administration of a 0.5-μg yeast-derived HBsAg (Y-HBsAg; LG...