Natural deletion is not unique in the coat protein (CP) of recombinant Plum pox virus (PPV) isolates in Hungary

Three Plum pox virus (PPV) isolates (Soskut1, Godollo2, Szigetcsep1), collected from apricot (Prunus armeniaca L.) trees in Hungary in 2008, were characterized in this study by sequence analysis of the RT-PCR amplified 3’ part of the viral genome spanning the 3’ part of the NIb gene the complete CP gene and the 3’UTR [3’NIb–CP–3’UTR] and also by restriction analysis of the PCR products derived from the 3’ part of the P3, the complete 6K1 and the 5’ end of the CI genes [3’P3–6K1–5’CI]. Phylogenetic analysis of the 3’NIb–5’CP region showed that one isolate (Godollo2) could be classified as a member of the PPV-Rec group, while the other two (Soskut1 and Szigetcsep1) belonged to PPV-D isolates. In the case of the recombinant Godollo2 isolate a 33-nucleotide (nt) in frame natural deletion was detected in the 5’ part of the CP gene during the sequence analysis of the cDNA fragment corresponding to the 3’NIb–CP–3’UTR region. Currently we have reported on another Hungarian PPV-Rec isolate (PPV-B1298) collected from plum that also had a shorter CP gene bearing a much larger 135-nt in frame natural deletion at a similar position to that of the Godollo2. The PPV-D type Soskut1 isolate showed an atypical restriction pattern in the 3’P3–6K1–5’CI region using EcoRI and DdeI endonucleases, respectively. Nucleotide sequence analysis of this region indicated that its unusual pattern is as a result of a point mutation affecting the EcoRI restriction site.Keywords: Plum pox virus, PPV, natural CP deletion mutant, EcoRI restriction sit

Serological, Pathological and Molecular Characterisation of Hungarian Pepper Mild Mottle Tobamovirus (PMMoV) Isolates

Last year pepper growers observed symptoms referring to virus-infection in pepper plantations in plastic tunnels. Infected plants showed mosaic symptoms or mottling of the leaves, while on the fruits necrotic spots developed. These symptoms referred to a tobamovirus infection. Collected samples were examined by serological and pathological methods, followed by the biological characterisation of the isolates. For serological studies the DAS-ELISA method was used, in which the pathogen was identified as pepper mild mottle tobamovirus. During the pathological examination different host-plants have been used including some pepper varieties containing different L genes (L + –L 4). It was found, that the Hungarian isolates belonged to the P 1,2 pathotype and were closely related to the Spanish isolate (PMMV-S). PCR- studies proved the presence of the PMMoV P 1,2 pathotype in Hungary as well

The Nucleotide Sequence of Two Hungarian Isolates of Wheat Dwarf Virus

Two wheat-infecting isolates of WDV-WDV-B and WDV-F- were collected in the field of Martonvásár and Nagykovácsi. The complete genomes were amplified by PCR, cloned into pBKS+ plasmid and sequenced. The nucleotide divergence in the total genome of the five isolates-WDV- Fra, WDV-Cz, WDV-Swe, WDV-B and WDV-F-originating from different part of Europe were found to be 0.44-1.69%. The four genes- MP, CP, RepA and Rep-and two non-coding region-LIR and SIR- were compared and a phylogenetic tree was constructed

Comparison of Hungarian and Bulgarian isolates of maize dwarf mosaic virus

Maize dwarf mosaic is the most widespread virus disease affecting corn production in Hungary and Bulgaria. Samples from virus infected maize were collected from different part of Bulgaria and employed test plants, ELISA serological method and RT-PCR in order to identify the viral pathogen. Maize dwarf mosaic virus (MDMV) was detected in all tested samples. For further investigation three MDMV isolates were selected and cloned. Cloned cDNAs representing the coat protein gene of the virus have been sequenced. The coat protein genes of Bulgarian and Hungarian isolates of MDMV were compared. The nucleotide sequence identity and amino acid sequence similarity of the coat protein region varied from 88% to 99.1% and from 95.1% to 99.6%, respectively. The N-terminal region of coat protein was compared with other members SCMV subgroup and phylogenetic tree was constructed