Passion Fruit Woodiness Virus Research Articles

Occurrence of passion fruit woodiness disease in the coastal lowlands of Kenya and screening of passion fruit genotypes for resistance to passion fruit woodiness disease

BackgroundPassion fruit (Passiflora edulis [Sims]) is an important economic fruit crop in Kenya, grown for domestic, regional and international markets. However, passion fruit production is constrained by both biotic and abiotic stresses. Passion fruit woodiness disease (PWD) complex is the most injurious viral disease responsible for yield losses of up to 100%. In East Africa, it is caused by potyviruses. The most effective way to manage PWD is by using resistant cultivars. The objectives of this study were to determine the occurrence of passion fruit woodiness disease in selected counties at the Coastal lowlands of Kenya and screen farmer preferred passion fruit genotypes for resistance to PWD.ResultsIn the present study, it was established that all surveyed farms in Kwale and Kilifi counties displayed passion fruit woodiness virus disease symptoms. The highest disease incidence of 59.16% and 51.43% was observed at Kilifi and Kwale counties, respectively. A significant difference (p < 0.05) in symptom severity was observed within the tested genotypes with purple and banana passion fruits having the highest and lowest AUDPC values, respectively, both under greenhouse and field conditions. ACP ELISA assays using universal potyvirus antiserum (Agdia Inc., Elkhat, IN) confirmed that the observed characteristic symptoms of woodiness disease were as a result of potyvirus infection.ConclusionsThe findings herein indicate that PWD is widespread in both Kilifi and Kwale counties with low to moderate disease incidence and severity. The observed prevalence, incidence and severity levels of PWD in Kwale and Kilifi counties could be aggravated by poor management practices such as non-sterilization of pruning tools, intercropping with target crops and crop rotation with the same target crops. Response of passion fruit genotypes to woodiness viruses was genotype dependent. There is need to sensitize farmers on the cause and spread of PWD and management strategies in order to increase production and enhance the quality of fruits.

First Report of Passiflora latent virus in Passion fruit (Passiflora edulis) in China.

Passion fruit (Passilora edulis, family Passifloraceae.) is an economically important fruit crop in many tropical and subtropical regions worldwide. It is widely planting in southern China, and in greenhouses throughout the country. In Mar 2022, symptoms of a viral-like infection were observed on the leaves of passion fruit plants in a 3-hectare greenhouse complex in Hohhot, China. Chlorotic lesions were observed on leaves of two vines of passion fruit and symptomatic leaves developed chlorotic spots, followed by systemic leaf chlorosis and necrosis. Dark ringed spots emerged on the surface of matured fruits (Figure 1). To confirm infectivity, mechanical transmission of the virus was performed by grinding leaves from two symptomatic passion fruit vines in 0.1M phosphate buffer pH 7, and the resulting two samples were each used to rub-inoculate carborundum-dusted leaves of three healthy passion fruit seedlings. Newly emerging leaves of inoculated plants developed mild mosaic symptoms 30-days after inoculation. Three samples from each of the two original symptomatic plants and two samples from each inoculated seedling tested positive using a Passiflora latent virus (PLV) ELISA Kit (Creative Diagnostics, USA). To further confirm the virus identity, total RNA from leaf samples from one of the original greenhouse symptomatic plants and one of the inoculated seedlings were extracted using an TaKaRa MiniBEST Viral RNA Extraction Kit (Takara, Japan). The two RNA samples were subjected to reverse transcription-polymerase chain reaction (RT-PCR) tests with virus specific primers PLV-F (5'-ACACAAAACTGCGTGTTGGA-3') and PLV-R (5'-CAAGACCCACCTACCTCAGTGTG-3') (Cho et al., 2020). RT-PCR products of the expected 571 bp were obtained from both the original greenhouse sample and inoculated seedling. Amplicons were cloned into the pGEM-T Easy Vector, and two clones per sample were Sanger sequenced bidirectionally (Sangon Biotech, China), and the sequence of one clone from one of the original symptomatic sample was uploaded to NCBI (GenBank OP320922.1). This accession had 98% nucleotide sequence identity with a PLV isolate from Korea (GenBank: LC556232.1). RNA extracts from two asymptomatic samples tested negative for PLV with both ELISA and RT-PCR tests. We also tested the original symptomatic sample for common occurring passion fruit viruses, including passion fruit woodiness virus (PWV), cucumber mosaic virus (CMV), east asian passiflora virus (EAPV), telosma mosaic virus (TeMV), papaya leaf curl Guangdong virus (PaLCuGdV), and the RT-PCR results were negative for those viruses. However, based on the systemic leaf chlorosis and necrosis symptoms, we cannot preclude a mixed infestation of other viruses. PLV affects fruit quality and has high potential to reduce market value. To our knowledge, this is the first report of PLV in China, which could provide a reference basis to PLV identification, prevention and control. Acknowledgments This research was carried out with the support of Inner Mongolia Normal University High-level Talents Scientific Research Startup Project (Grant no. 2020YJRC010). Supplementary material Figure 1. Mottle, leaf distortion, puckering symptoms on old leaf (A), mild puckering symptom on young leaf (B), and ring-striped spots symptoms on fruit (C) of the PLV infected passion fruit plant in China.

Passion fruit woodiness virus (passionfruit woodiness disease)

Passion fruit woodiness virus (passionfruit woodiness disease)

Next generation sequencing as a tool in modern pest risk analysis: a case study of groundnuts (Arachis hypogaea) as a potential host of new viruses in western Kenya

Groundnut (Arachis hypogaea, L.) is grown in diverse environments throughout the semi-arid and sub-tropical regions of the world. Poor yields of 500-800kg/ha are attributed to poor agronomic practices, pests and diseases. The major disease reported in Kenya is Groundnut rosette disease (GRD). But recent observations in the field showed that the crop has varied and severe symptoms in addition to those caused by GRD. This required deeper analysis to establish the causal agents. Groundnut samples with virus-like symptoms were collected from western Kenya in 2016. Total RNA was extracted using All Prep RNA Mini Kit. Five mRNA libraries were prepared using the Illumina TrueSeq stranded mRNA library Prep Kit and pooled for multiplexed sequencing using an Illumina HiSeq 2500 to generate paired end reads (FastQ Sanger). The reads were analysed in the Galaxy project platform (customized). Quality reads were first mapped onto plant genome Refseq and unmapped reads isolated and mapped onto virus Refseq using Bowtie 2 (v2.2.3). Groundnut rosette virus satellite RNA, Groundnut rosette virus, Groundnut rosette assistor virus, Ethiopian tobacco bushy top virus, Cowpea polerovirus 2, Chickpea chlorotic stunt virus, Melon aphid-borne yellow virus, Phasey bean mild yellow virus, Beet mild yellowing virus, White clover mottle virus and Cotton leafroll dwarf virus were identified in four libraries. Other viruses (with less than 100 reads) including Bean common mosaic virus, Bean common mosaic necrosis virus, Cowpea chlorotic mottle virus RNA 3, Broad bean mottle virus RNA 3, Passion fruit woodiness virus among others were also mapped. Some of the viruses common in western Kenya were confirmed by PCR. The presence of at least three viruses in groundnuts in Western Kenya highlights the importance of starting a germplasm clean-up program of the plant material used as seed in this crop. Key words: Groundnuts, NGS, RefSeq, Viruses.

First Report of Cucurbit Aphid-Borne Yellows Virus in Passion Fruit Plants Exhibiting Mosaic and Mottling in China

First Report of Cucurbit Aphid-Borne Yellows Virus in Passion Fruit Plants Exhibiting Mosaic and Mottling in China

Produção de mudas de maracujazeiro-azedo em ambiente protegido: dimensionamento e manejo do ambiente de produção

A produção de mudas de maracujazeiro-azedo em ambiente protegido é uma tecnologia diferenciada, que qualifica o setor produtivo a reduzir ou até eliminar o risco de disseminação de doenças e pragas através das mudas. Também proporciona a obtenção de mudas avançadas (maiores que 80cm de altura), que possibilitam antecipação de colheita e maior produtividade em áreas de ocorrência endêmica da virose do endurecimento dos frutos do maracujazeiro, principal doença dessa cultura. Termos para indexação: Passiflora edulis; virose do endurecimento dos frutos; mudas sadias.

The virus causing passionfruit woodiness disease in Taiwan is reclassified as East Asian passiflora virus

Based on filamentous particles, aphid transmission, and symptoms of distorted, size-reduced, woody fruits, the major potyvirus associated with passionfruit woodiness disease (PWD) in Taiwan has been regarded as Passionfruit woodiness virus (PWV) for decades. In this study, the genomes of four potyvirus isolates, originally collected from orchards with PWD in Taiwan and re-designated as Poty-TW, Poty-0920-6, Poty-dpd and Poty-pt, were sequenced for molecular characterization. Our results revealed that the CP genes of Poty-TW and Poty-0920-6 share nucleotide (nt) identities/amino acid (aa) identities of 97.7/95.9 and 98.5/97.2%, respectively, with that of East Asian passiflora virus (EAPV) isolate AO of Japan, and the CP genes of Poty-dpd and Poty-pt share nt/aa identities of 95.3/96.2 and 94.9/97.6% respectively, with that of EAPV isolate IB of Japan. The genomic sequences of PWD-associate viruses in Taiwan also share high degrees of homology with that of EAPV-AO (TW and 0920-6 isolates > 98%) and EAPV-IB (dpd and pt isolates > 88%). However, the CP genes of four PWD-associated viruses from Taiwan share only 67.6–69.4% nt identities with that of PWV Australia MU isolate, does not satisfy the ICTV criteria (> 76%) to be regarded as a strain of PWV. A field survey with 175 samples from different areas of Taiwan demonstrated that the PWD-associated potyvirus is mainly caused by EAPV. Hence, our results indicate that the major potyvirus causing PWD in Taiwan should be reclassified as EAPV.

First Report of Passion fruit woodiness virus Associated with Passion Fruit Woodiness Disease of Passion Fruit in Nigeria

First Report of <i>Passion fruit woodiness virus</i> Associated with Passion Fruit Woodiness Disease of Passion Fruit in Nigeria

Dissimilarity based on morphological characterization and evaluation of pollen viability and in vitro germination in Passiflora hybrids and backcrosses

Brazil is considered the main center of the genetic diversity and greatest worldwide producer of passion fruit. Passionfruit woodiness virus (Cowpea aphid born mosaic virus) is an important pathogenic agent of the passion fruit crop, causing severe losses in yield. Wild species of Passiflora are valuable sources of genetic resistance to this disease. Interspecific crosses are a promising method to incorporate resistance genes in commercial species (Passiflora edulis Sims.), despite problems with male sterility in developed hybrids. The objective of the present work was to study the dissimilarity based on morphological characteristics, and the viability and in vitro germination of pollen grains of progenitors, F1 hybrids, as well as progenies of the first generation of backcross BC1 [(P. edulis × P. cincinnata) × P. edulis]. Analysis of the severity of the viral disease showed that most genotypes were considered as susceptible to highly susceptible. The resistant hybrids did not show symptoms of foliar deformation. Cluster analysis showed two major groups; one represented by P. cincinnata and the second group by the hybrids and recurrent progenitor P. edulis. Morphological characterization of the hybrids showed phenotypic variation as to the color and shape of flowers, although the descriptors used were not able to show these differences. As expected, the progenitors (P. edulis and P. cincinnata) presented higher percentages of pollen viability, followed by the BC1-H45 progenies. The progenies of the BC1 will also be evaluated in the future with molecular markers aiming to accelerate the selection of hybrids with higher percentages of the genome of the recurrent parent.

THE NEEM OIL IN PASSION FRUIT MANAGEMENT

Brazil is the largest producer of yellow passion fruit; however declined in production is due to diseases caused by Passion fruit Woodiness Virus (PWV) and Cowpea Aphid-Borne Mosaic Virus (CABMV). Another problems faced by industry are the high water and quality loses and thus, reduce the life of the fruits. The aim of this study was to verify the efficacy of natural neem oil in PWV/CABMV managements, and post-harvest characteristics of fruits and the effect of neem cake on the growth of passion fruits plants. In this study, the yellow passion fruit (Passiflora edulis Sims f. Flavicarpa Deg.) of Afruvec selection, was subjected to fertilization by neem cake and sprayed with neem oil at 0.5%. The vegetative growth, stem diameter, and the incidence of the typical symptoms of PWV/CABMV were evaluated. The effect of neem on the fruits in postharvest was evaluated by water loss, firmness of fruits, and chemical analysis was carried as ºBrix, pH and Total Titratable Acidity. The results show that neem oil has great potential to control the incidence of virus in passion fruit, due to the action of repellence. The best result was in the group with oil application every 15 days, resulting up to 42% of plants with symptoms at 162 days after planting, whereas 55% to 65% of control plants with symptoms. In growth and post-harvest, neem cake and neem oil showed no significant effects.

Efficacy of acibenzolar-S-methyl (Bion®) treatment of Australian commercial passionfruit, Passiflora edulis f. sp. flavicarpa, on resistance to Passionfruit woodiness virus (PWV) and activities of chitinase &amp; β-1,3-glucanase

This greenhouse study investigated the efficacy of acibenzolar-S-methyl (Bion®) treatment of lower leaves of passionfruit, (Passiflora edulis f. sp. flavicarpa), on Passionfruit woodiness disease and activities of two pathogenesis-related proteins, chitinase and β-1,3-glucanase after inoculation with passionfruit woodiness virus (PWV). All Bion® concentrations reduced disease symptoms, but the concentration of 0.025 g active ingredient (a.i.)/l was the most effective, reducing disease severity in systemic leaves by 23, 29 and 30 % compared with water-treated controls at 30, 40 and 50 days post inoculation (dpi) with PWV, respectively. Correspondingly, relative virus concentration as determined by DAS-ELISA in the upper, untreated leaves (new growth) above the site of inoculation at 50 dpi was reduced by 17 and 22 % in plants treated with 0.025 and 0.05 g a.i./l, respectively. Bion® treatment and subsequent inoculation with PWV increased chitinase and β-1,3-glucanase activities in the new leaves above the site of inoculation at 30 dpi with PWV. It was concluded that optimal protective Bion® treatment concentrations were 0.025 and 0.05 g a.i./l.

Complete nucleotide sequence of a new isolate of passion fruit woodiness virus from Western Australia

We determined the complete genome sequence of the passion fruit woodiness virus Gld-1 isolate (PWV-Gld-1) from Australia and compared it with that of PWV-MU-2, another Australian isolate of PWV. The genomes shared high sequence identity in both the complete nucleotide sequence and the ORF amino acid sequence. All of the cleavage sites of each protein were identical to those of MU-2, and the sequence identity for the individual proteins ranged from 97.2% to 100.0%. However, the 5' untranslated region (5'UTR) of the Gld-1 isolate shared only 46.8% sequence identity with that of PWV-MU-2 and was 177 nucleotides shorter. Re-sequencing of the 5'UTR of MU-2 revealed that the 5' end of the original sequence includes an artifact generated by deep sequencing.

First Report of Passiflora virus Y Infecting Macroptilium atropurpureum in Taiwan.

Macroptilium atropurpureum (siratro plants) is a perennial wild legume plant introduced to Taiwan as a forage crop in 1961 (3) and has become a naturalized weed found all over the island. In 2010, siratro plants with virus-like symptoms of mosaic and leaf deformation were observed on the campus of Da-Yeh University in central Taiwan. Flexuous virus-like particles about 750 × 12 nm were observed in the crude sap extracted from symptomatic leaves with a transmission electron microscope. Crude sap was mechanically inoculated to Chenopodium quinoa and local lesions can be observed on inoculated leaves 4 to 5 days after inoculation. Virus was purified from the leaves of inoculated C. quinoa with modified protocols of Gonsalves and Ishii (2). The virus coat protein (CP) consisted of a single major peptide with relative molecular weight of approximately 33 kDa when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Viral RNA extracted from the purified virus was used as a template and was primed with several primer sets corresponding to potyviruses and carlaviruses in reverse transcription-PCR to amplify possible corresponding cDNA fragments. After several attempts, a cDNA fragment of about 1,300 bp could be amplified with the degenerated primer set of BCMNV-F (5'CCDTGGACDGTWGGVATGAC3') and BCMNV-R (5'CACCAHACCATRAARCCATTCAT3'), which were designed on the basis of the conserved region of the nuclear inclusion b (NIb) and CP genes of some potyviruses including Bean common mosaic necrosis virus, Soybean mosaic virus, Blackeye cowpea mosaic virus, East Asian passiflora virus, and Passion fruit woodiness virus. BLAST analyses showed the amplicon was highly homologous to that of Passiflora virus Y (PaVY). Together with oligo dT, a specific primer (5'GATGACACTCAAATGGCTG3') corresponding to PaVY CP was used to amplify the cDNA fragment of the most 3' region of the viral RNA (about 800 bp). The assembled cDNA fragment of 1,958 bp (Accession No. AB679294) contains a partial NIb gene (877 nt), a complete CP gene (819 nt), and the 3' noncoding region (262 nt). The CP gene shared sequence identities of 89.4 to 98.9% and 92.7 to 98.9% in nucleotide and amino acid, respectively, to that of documented PaVY isolates. PaVY has also been found to be infecting Vigna trilobata, Rhynchosia minima, Clitoria ternatea, and Passiflora foetida in Australia (1). Here we present the first report to our knowledge of PaVY and its infection of siratro (M. atropurpureum) in Taiwan. Additional work is needed to investigate the spread of PaVY and its interaction with other legume plants in Taiwan.

Characterization and Distribution of a Potyvirus Associated with Passion Fruit Woodiness Disease in Uganda.

This article describes the incidence and etiology of a viral disease of passion fruit in Uganda. Symptoms, including those characteristic of passion fruit woodiness disease (PWD), were observed on 32% of plants in producing areas. Electron microscopic observations of infected tissues revealed flexuous filaments of ca. 780 nm. Enzymelinked immunosorbent assays indicated a serological relationship with Cowpea aphid-borne mosaic virus (CABMV) and Passion fruit ringspot virus (PFRSV). In host range studies, only species in the families Solanaceae and Chenopodiaceae were susceptible, and neither Vigna unguiculata nor Phaseolus vulgaris became infected. Coat protein (CP) gene sequences of eight isolates exhibited features typical of potyviruses and were highly similar (88 to 100% identity). However, the sequences had limited sequence identity with CP genes of two of the three potyviruses reported to cause PWD: East Asian Passiflora virus and Passion fruit woodiness virus (PWV). Deduced amino acid sequences for the CP of isolates from Uganda had highest identity with Bean common mosaic necrosis virus (BCMNV) (72 to 79%, with evolutionary divergence values between 0.17 and 0.19) and CABMV (73 to 76%, with divergence values between 0.21 and 0.25). Based on these results and in accordance with International Committee for Taxonomy of Viruses criteria for species demarcation in the family Potyviridae, we conclude that a previously unreported virus causes viral diseases on passion fruit in Uganda. The name "Ugandan Passiflora virus" is proposed for this virus.

Analysis of passion fruit rinds (Passiflora edulis): isoorientin quantification by HPTLC and evaluation of antioxidant (radical scavenging) capacity

The content of isoorientin in passion fruit rinds (Passiflora edulis fo. flavicarpa O. Degener) was determined by HPTLC (high performance thin layer chromatography) with densitometric analysis. The results revealed a higher amount of isoorientin in healthy rinds of P. edulis (92.275 ± 0.610 mg L-1) than in rinds with typical symptoms of PWV (Passion fruit Woodiness Virus) infection (28.931 ± 0.346 mg L-1). The HPTLC data, allied to assays of radical scavenging activity, suggest the potential of P. edulis rinds as a natural source of flavonoids or as a possible functional food.

MANAGEMENT STRATEGIES FOR FUNGAL DISEASES IN PASSION FRUIT PRODUCTION SYSTEMS IN KENYA

Diseases have been reported to cause yield losses of 80-100% in passion fruit production systems in Kenya. These include, brown spot (Alternaria passiflorae), anthracnose (Colletotrichum passiflorae), crown/collar rot (Fusarium solani), wilt (Fusarium oxysporum f. sp. passiflorae), dieback (Fusarium spp. and Phytophthora nicotianae var. parasitica) and passion fruit woodiness virus disease complex. Surveys were conducted in passion fruit growing regions of Kenya, to collect information on disease prevalence, severity and crop management practices carried out by farmers. Brown spot and dieback diseases affected passion fruit most commonly across 8 districts with 55-100 and 64-100% of the farms having the two diseases, respectively. Farmers were interrogated on management strategies used to ensure their crops are disease free and healthy. Investigations revealed that over 50% of the farmers did not undertake field sanitation measures that reduce disease inoculum in fields, such as pruning , burning of infected plant parts and disinfection of tools used on the farms. Such measures could reduce pathogen. It was also realised that most farmers did not frequently scout for initial disease symptoms on their farms so as to control them promptly. Control strategies were applied when plants were already under high disease pressure. These factors led to a rapid spread of fungal diseases. Incidences of Fusarium wilt disease were relatively lower than those of brown spot and dieback. This was attributed to the planting of seedlings that had been grafted onto yellow passion fruit rootstocks, which are known to be tolerant to Fusarium wilt. This study emphasizes the need to educate farmers on the importance of field sanitation in minimising disease incidences and spread and to boost crop health through the use of fertilizers and manure.

Efficient shoot regeneration from direct apical meristem tissue to produce virus-free purple passion fruit plants

Purple passion fruit is an important fresh table fruit. At present, the production of passion fruit is decreasing because of the spread of viral diseases throughout the planting area. The aim of this research was to propagate virus-free plants using a tissue culture technique involving the apical meristem of purple passion fruit. Shoot tips were excised to a length of 2 mm and the shoots were regenerated by culturing on Murashige and Skoog medium supplemented with different concentrations of benzyladenine (BA) (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mg/l) and 1-naphthaleneacetic acid (NAA) (0.2, 0.5, 1.0, 1.5 and 2.0 mg/l). Root formation was promoted using different concentrations of indole-3-butyric acid (IBA) (0.0, 0.2, 0.4, 0.6, 0.8 and 1.2 mg/l). A greater number of shoots were produced with BA concentrations of 1.0 and 1.5 mg/l than with any other BA concentrations tested (less than 1.0 mg/l or greater than 1.5 mg/l). However, when NAA at any concentration was included in the medium, no shoots were produced in culture. The cultures including 1.0 mg/l and 1.5 mg/l BA were then subcultured four times every two weeks. Initially, the tissue cultured in the 1.5 mg/l BA medium grew faster than that cultured in the 1.0 mg/l BA medium. The tissue cultured with 1.5 mg/l BA generated many short shoots, whereas the tissue cultured with 1.0 mg/l BA, generated long shoots that could be subcultured into individual plants. These regenerated shoots were assayed for the presence of the passion fruit woodiness virus using ELISA or a test strip kit; only virus-free shoots were used for further propagation. Root formation was very good in IBA concentrations of 0.4 and 0.6 mg/l. Thus, virus-free plants could be successfully regenerated directly from the apical meristem.

Indigenous and introduced potyviruses of legumes and Passiflora spp. from Australia: biological properties and comparison of coat protein nucleotide sequences

Five Australian potyviruses, passion fruit woodiness virus (PWV), passiflora mosaic virus (PaMV), passiflora virus Y, clitoria chlorosis virus (ClCV) and hardenbergia mosaic virus (HarMV), and two introduced potyviruses, bean common mosaic virus (BCMV) and cowpea aphid-borne mosaic virus (CAbMV), were detected in nine wild or cultivated Passiflora and legume species growing in tropical, subtropical or Mediterranean climatic regions of Western Australia. When ClCV (1), PaMV (1), PaVY (8) and PWV (5) isolates were inoculated to 15 plant species, PWV and two PaVY P. foetida isolates infected P. edulis and P. caerulea readily but legumes only occasionally. Another PaVY P. foetida isolate resembled five PaVY legume isolates in infecting legumes readily but not infecting P. edulis. PaMV resembled PaVY legume isolates in legumes but also infected P. edulis. ClCV did not infect P. edulis or P. caerulea and behaved differently from PaVY legume isolates and PaMV when inoculated to two legume species. When complete coat protein (CP) nucleotide (nt) sequences of 33 new isolates were compared with 41 others, PWV (8), HarMV (4), PaMV (1) and ClCV (1) were within a large group of Australian isolates, while PaVY (14), CAbMV (1) and BCMV (3) isolates were in three other groups. Variation among PWV and PaVY isolates was sufficient for division into four clades each (I-IV). A variable block of 56 amino acid residues at the N-terminal region of the CPs of PaMV and ClCV distinguished them from PWV. Comparison of PWV, PaMV and ClCV CP sequences showed that nt identities were both above and below the 76-77% potyvirus species threshold level. This research gives insights into invasion of new hosts by potyviruses at the natural vegetation and cultivated area interface, and illustrates the potential of indigenous viruses to emerge to infect introduced plants.

The complete genome sequence of a Passion fruit woodiness virus isolate from Australia determined using deep sequencing, and its relationship to other potyviruses

The complete genome sequence (9,858 nucleotides) of the Passion fruit woodiness virus isolate MU-2 was determined using Illumina sequencing. The large open reading frame (ORF) encodes a polyprotein containing 3,086 amino acids, with an AUG start codon and UAA stop codon. The polyprotein yielded 11 proteins (P1, HC-Pro, P3, PIPO, 6K1, CI, 6K2, NIa-VPg, NIa-Pro, NIb and CP). Putative cleavage sites between them were identified by sequence comparison to those of other known potyviruses. Accuracy of the genome sequence information was provided by 42-1691-fold sequence coverage, and viral RNA accounted for 7.38% of total polyadenylated RNA from the host plant.

Nucleotide Sequence of the Coat Protein Gene of the Malaysian Passiflora Virus and its 3’ Non-Coding Region

Problem statement: In this study, we identified the full length Coat Protein (CP) gene of the Malaysian Passiflora Virus (MPV) and its 3' non-coding region . The CP gene of the MPV contained 285 amino acid residues. Approach: Pairwise comparison of the MPV CP region with four other potyviruses, namely East Asian Passiflora Vir us (EAPV), Passionfruit Woodiness Virus (PWV), Bean Common Mosaic Virus (BCMV) and Soyabean Mosaic Virus (SMV) revealed amino acid sequence similarities ranging from 72-95%. Results: The 3' non-coding region of the MPV, which consists of 255 nucleotides, showed 69-95% nucleoti de sequence identity when compared with the four potyviruses. The highest (95%) sequence simila rities were detected with PWV and EAPV. An analysis of the deduced amino acid sequences reveal ed the presence of consensus motifs (DAG tripeptides) characteristic of potyviruses. DAG tri peptides had been reported to be essential for aphi d transmission. Conclusion: From the amino acid sequence alignment and identit y level observed among the four other potyviruses, we concluded that MPV is a member of the genus Potyvirus and was closely related to both PWV and EAPV.