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Dasheen mosaic virus (DsMV) is one of the major viruses affecting taro (Colocasia esculenta) production worldwide. Whole genome sequences were determined for two DsMV strains, Hawaii Strain I (KY242358) and Hawaii Strain II (KY242359), from taro in Hawaii. They represent the first full-length coding sequences of DsMV reported from the United States. Hawaii Strains I and II were 77 and 85% identical, respectively, with other completely sequenced DsMV isolates. Hawaii Strain I was most closely related to vanilla mosaic virus (VanMV) (KX505964.1), a strain of DsMV infecting vanilla in the southern Pacific Islands. Hawaii Strain II was most closely related to a taro DsMV isolate CTCRI-II-14 (KT026108.1) from India. Phylogenetic analysis of all available DsMV isolates based on amino acid sequences of their coat protein showed some correlation between host plant and genetic diversity. Analyses of DsMV genome sequences detected three recombinants from China and India among the six isolates with known complete genome sequences. The DsMV strain NC003537.1 from China is a recombinant of KJ786965.1 from India and Hawaii Strain II. Another DsMV strain KT026108.1 is a recombinant of Hawaii Strain II and NC003537.1 from China. The third DsMV strain KJ786965.1 from India is a recombinant of Hawaii Strain II and NC003537.1 from China. To our knowledge, this is the first report of recombination events in DsMV. Both Hawaii Strains I and II of DsMV were found widespread throughout the Hawaiian islands.

Observations were carried out on Anthurium sp growing at Mediterranean region (Adana, Mersin and Antalya provinces) of Turkey in 2015-2017. During the studies virus-like symptoms in plants; systemic chlorotic mosaic and irregular uniformity on leaf and petals were recognized. Eleven of 73 samples showed positive response with the Potyvirus group specific antibodies and their results were also confirmed by RT-PCR. The 327 bp products via using the Potyvirus-specific primers, MJ1 and MJ2 were run in 1.5% agarose gel. Further amplifications were made with the 3‘UTR and 3‘end of the coat protein of the viral genome. RT-PCR analysis using the primer MJ1 and M4T resulted in an amplification of 719 bp amplicon. Direct sequencing of RT-PCR products and BLAST results have showed that there were two clades between 96-99% among the Mediterranean coast DsMV isolates. The data are available in Genebank with accession Number MK758088/Antalya; MK758087/Yenice). DsMV infection on Anthurium sp, was determined serologically and molecularly. To our knowledge, this is the first molecular record describing the occurrence, distribution and genome organisation of DsMV isolates that have been infecting Flamingo flowers at the Mediterranean coast of Turkey. Findings may have shown an evidence about uncontrolled distribution from Northern corner to Southern side. © 2019, ALÖKI Kft., Budapest, Hungary.

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Dasheen mosaic virus (DsMV) the main causative agent of mosaic disease in elephant foot yam (Amorphophallus paeoniifolius) belongs to Potyviridae. The complete genome sequence of DsMV infecting A. paeoniifolius in Kerala state, India was assembled from the whole transcriptome sequencing reads of diseased host samples. The sequence of the virus which showed 83% identity with DsMV infecting Zantedeschia aethiopica (China) was confirmed through amplification and sequencing with primers designed based on the assembled sequence. Unambiguous recombination events mainly confined to the 5′ terminal 4000 nucleotides of the genome with phylogenetically related potyviruses were recognized. The length and genome composition towards the 3′ end comprising NIb, CP and 3′ UTR were not dependent on the host or the source region.

Taro is an important crop in parts of the world, especially in the Pacific Islands. Like all plants, it is also susceptible to virus infections that could result in diseases, which negatively affects the source of food and trade revenue. Understanding the biology of taro viruses could improve current knowledge regarding the relationship between viruses and taro, thus allowing for a better approach towards the management of the diseases that are associated with them. By compiling and discussing the research on taro and its four major viruses (Dasheen mosaic virus, Taro bacilliform virus, Colocasia bobone disease virus, and Taro vein chlorosis virus) and a relatively new one (Taro bacilliform CH virus), this paper explores the details of each virus by examining their characteristics and highlighting information that could be used to mitigate taro infections and disease management.

Taro (Colocasia esculenta [L.] Schott) is a root crop widely grown in tropical and subtropical countries (Banjaw 2017). It makes up about 80% of the aroids (family Araceae) cultivated in Bangladesh (Bhuiyan et al. 2011). Dasheen mosaic virus (DsMV) is a potyvirus transmitted by aphids to many aroids (Zettler and Hartman 1987). The vegetative propagation of taro contributes to the widespread distribution of viruses in this crop (Kazmi et al. 2015). In December 2016, virus-like symptoms including feathery chlorotic mottling and distortions in leaves were observed on taro (cultivar Panikachu) growing in Chandpur (23.2321° N, 90.6631° E) in Bangladesh. Thirteen taro samples with feathery mottling and distorted leaves and three nonsymptomatic leaves were collected and tested for potyvirus infection using universal potyvirus-specific ELISA (Agdia, Elkhart, IN) and universal potyvirus-specific reverse transcription polymerase chain reaction (RT-PCR) (Zheng et al. 2010), respectively. Eight of the 13 symptomatic taro samples tested positive for potyvirus in both tests, whereas the three nonsymptomatic taro leaves tested negative. To identify the specific potyvirus involved, amplicons (332 bp) of the NIb region that were generated by RT-PCR using universal potyvirus-specific primers were sequenced (accession MH036416) (Wang et al. 2017). BLASTn analysis of the sequences showed that this virus shared 87% nucleotide identity with a DsMV isolate from Florida (AF048981). Two additional sets of primers were also used to further characterize the isolate: DsMV gene CI-specific primers DMV 5708-5731-F/DMV 6131-6154-R (Wang et al. 2017); and DsMV gene CP-specific primers DMV 9398-9419-F (5′-CTTGCGTCAGATAATGCATCAC-3′)/DMV 9965-9985-R (5′-CACCGTGCACGAAGCATCTCG-3′). BLASTn analysis of the 407-bp CI amplicon (accession MH036417) shared 91% identity with a Chinese isolate of DsMV (AJ298033), and the 564-bp CP amplicon (accession MH036418) shared 92% identity with the same Chinese isolate of DsMV. Eight PCR-positive samples also tested positive for DsMV by triple-antibody sandwich ELISA using a DsMV-specific antibody (Agdia). Moreover, all 13 samples were tested for taro vein chlorosis virus (Atibalentja et al. 2018), cucumber mosaic virus (Wang et al. 2014), and taro bacilliform CH virus (Wang et al. 2017) by RT-PCR, and the results were negative. To our knowledge, this is the first report of DsMV infecting taro plants in Bangladesh. Our results will be useful for further genome characterization and management of DsMV in Bangladesh to mitigate potential threats to taro production there.

A filamentous virus was isolated from taro (Colocasia esculenta Schott) showing mosaic and chlorotic feather-ing symptoms in Chuncheon, Gangwon province in 2002. Based on ELISA, its appearance in electron microscope, serological relationships, and RT-PCR using specific primer and nucleotide sequence analysis of the CP gene, the isolated virus was identified as Dasheen mosaic virus (DsMV) and designated as Korean isolated (DsMV-Kr). DsMV was not serologically related to Zantedeschia mosaic virus (ZaMV), which has been reported to infect an Araceae plants. Since the coat protein revealed electrophoretic heterogeneity, about 42 kDa, 39 kDa and 31 kDa by SDS-PAGE, an improved purification method was established for the production of antisera against DsMV-Kr. The purification method used in this study may be effectively applied to the purification of other filamentous viruses.

In Fiji, taro (Colocasia esculenta Schott.) varieties grown in vitro from shoot tips, and pathogen‐tested (PT) to meet guidelines for international transfer, were compared with field‐collected (FC) plants over 3 years. For three varieties, ‘Toakula’, ‘Samoa’ hybrid, and ‘Tausala ni Samoa’, there were no significant differences between heights and corm yields of PT and FC plants. For a fourth variety, ‘Samoa’, PT plants outgrew FC plants and yields were more than double. This variety, considered best adapted to hill slopes, grew well in alluvial coastal soils after in vitro culture. A major change appeared to be in response to Dasheen mosaic virus infection. By the third trial, an average 13.2 of 18 FC plants per plot showed virus symptoms compared to 2.6 in PT plots; and whereas FC plants were stunted (0.75 m) and low yielding (5.4 t/ha) PT plants were similar in height and yield to the other varieties (1.11 m and 11.8 t/ha). The results could not be explained by the elimination of a second virus...

コンニャクモザイクウイルス(KMV)とサトイモモザイクウイルス(DasMV)の理化学的性状および血清学的性質について比較した。核酸の分子量はグリオキザール変性下でのアガロースゲル電気泳動法によりKMVが3.21×106であったが,DasMVは3.42×106であった。外被タンパク質の分子量は12.5% SDS-PAGEにより,KMVは35.5Kであったが,DasMVは32.5Kと40.0Kの二つのタンパク質が検出された。リシルエンドペプチダーゼで処理したDasMVのそれぞれのタンパク質のペプチドを逆相高速液体クロマトグラフィーで比較したところ,両者はほぼ同じ組成のものであった。KMVはELISA法でダイズモザイクウイルス(SoyMV)およびカボチャモザイクウイルス-2(WMV-2)とは血清学的類縁関係が認められたが,DasMVを含む他の6種のpotyvirusとは,血清学的関係は認められなかった。同様に寒天ゲル内拡散法およびウエスタンブロッティング法によってもKMVとSoyMVおよびWMV-2の間に血清学的類縁関係が認められた。

In April 2013, yellowing and distortion of leaves as well as mosaic and chlorotic ring symptoms were observed on calla lilies ( Zantedeschia sp.) in nurseries in Bosnia and Herzegovina (Fig. 1). The virus-like symptoms were present in …

A feathery mottle pattern, typical of dasheen mosaic virus infection, was observed on the leaves of one Japanese and two traditional New Zealand cultivars of taro (Colocasia esculenta Schott) grown in the Auckland area of New Zealand. Electron microscopy and serological testing confirmed the presence of dasheen mosaic virus.

RESUMO Identificacao sorologica de Dashim mosaic virus em Anturio no estado do Ceara Os anturios (Anthurium spp.) sao cultivados nas serras umidas do estado do Ceara, especialmente, no Macico de Baturite e vem despontando como promissora ornamental no mercado internacional. Plantas com sintomas de virus foram constatadas em visitas de inspecao a plantios comerciais de anturios no Macico de Baturite. Testes sorologicos de Elisa indireto com amostras de flores e de folhas de plantas com sintomas apresentaram resultados positivos para Dasheen mosaic virus, familia Potyviridae, genero Potyvirus. A constatacao de inclusoes citoplasmatica em celulas da epiderme de plantas infetadas confirmou a infeccao por virus do genero Potyvirus. Este e o primeiro registro da incidencia do DMV no Ceara.

750 × 11 nm) were observedin both the leaf epidermis of infected plants and purifiedpreparations. In ultrathin sections of the leaves, character-istic potyvirus-like cylindrical inclusions were observed.In double-diffusion tests and DAS-ELISA, the purifiedpreparations reacted with DsMV-specific antibodies (Agdia,USA). These observations lead to the conclusion that thevirus infecting these four aroids is DsMV. AlthoughDsMV has recently been reported infecting the edibleelephant foot yam (

Taro, Colocasia esculenta (L.) Schott (Araceae) is a monocot grown as a starchy root crop in much of the tropics and subtropics. It is subject to a number of fungal, bacterial, and viral diseases. Viral diseases have inhibited the cultivation of taro in parts of New Guinea and the Solomon Islands where taro is an integral part of the culture. Two different viruses, a Rhabdovirus, the Large Bacilliform Particle (LBP), and a smaller bacilliform virus, are the cause. Dasheen Mosaic Virus, a Potyvirus, has been found wherever taro is cultivated and produces a leaf mottle but is not lethal to plants.Colocasia esculenta cv K268 corms, infected with virus, were obtained from Michael Pearson, Department of Botany, University of Papua New Guinea, Port Moresby, New Guinea. Upon planting some of the corms produced leaves with virus symptoms. Others were symptomless but symptoms could be induced by stress.

Expression of mosaic symptoms on young taro plants (Colocasia esculenta (L.) Schott) from dasheen mosaic virus infected corms was promoted by root cutting or high soil temperature (40C) at sprouting stage. Under field condition the percentage of taro plants showing mosaic symptoms was highest at the beginning of July, then decreased, and increased again after the end of August.

Philodendron verrucosum Mattieu was shown to be a good local lesion host for dasheen mosaic virus. Other six Philodendron species so far tested were systemically infected with the virus, showing distinct mosaic symptoms. Anthurium scandens var. violaceum showed faint mottling of the leaves.

Dasheen mosaic virus (DMV), was identified by manual sap transmission, serological tests and by the presence of flexuous rod particles and pinwheel inclusions. It was recorded in the wild and cultivated aroids Alocasia macrorrhizos, A. micholitziana, Colocasia esculenta, C. Gigantea, Dieffenbachia spp. and Xanthosoma sp. which were found with symptoms during surveys in coastal Queensland.