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

Comparison of N-terminal Region of Coat Protein in Zucchini Yellow Mosaic Potyvirus Isolates

Zucchini yellow mosaic potyvirus (ZYMV)was isolated in Hungary from cucumber for the first time in 1995 and now it is widespread causing devastating epidemics in cucurbit crops. Four isolates were chosen from different cucurbit plants collected in 1995 and 1999 and mole- cular variability of N-terminal region of coat protein was studied.Hungarian isolates show lower molecular variability within themselves than with ZYMV isolates from other geographical origins.Hungarian isolates have amino acid sequences specific only to them that suggest common ancestor

Variation of some morphological and molecular characteristics of Hungarian Crivellia and Brachycladium isolates from opium poppy (Papaver somniferum L.)

A destructive seed-borne pathogen, formerly described as Pleospora papaveracea affects opium poppy (Papaver somniferum L.) plants, grown in Hungary, causing considerable qualitative and quantitative losses. The symptoms of the disease were frequently observed in the field between 1999 and 2006. Seventeen Hungarian isolates were obtained from poppy and cultures were established on malt extract agar from naturally infected seeds, diseased foliage, pods and stem. The pathogens proved to be Crivellia papaveracea and a distinct taxon, Brachycladium papaveris based on morphological characterization of conidia, conidiophores and cultures, moreover molecular investigation of the ITS region. Significant morphological differences were observed among the isolates originating from distinct plant parts, however, cultural characteristics were similar. Molecular studies revealed that morphological and cultural differences or similarities do not correspond with taxonomic position of the isolates. Morphological variation of the isolates mainly depended on their origin and might be explained with the differences of microclimatic conditions

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