First Report Of Cucumber Mosaic Virus Research Articles

Biological, Serological and Molecular Characterization of Cucumber mosaic virus (CMV) Infecting Cucurbita moschata (Duchene ex. Poir) (Summer Squash) in Itu and Uyo Local Governments Areas, Akwa Ibom State, Nigeria

Cucurbita moschata is an edible member of the family Cucurbitaceae. The plant is commonly observed showing typical virus-like symptoms during the growing season in Akwa Ibom State, Nigeria. A total of 7 leaf samples showing typical virus-like symptoms were collected from C. moschata in different locations in Itu and Uyo Local Government, Akwa Ibom State. All the virus isolates used in this study were sap transmissible with a wide host range. The virus isolates irrespective of the place of collection were transmitted in a fore-gut manner by A. spiraecola. Aphis citricida did not transmit the viruses. All the virus isolates reacted positively to cucumovirus polyclonal antibody in antigen coated plate-ELISA (ACP-ELISA). Gel electrophoresis of the cDNA of the virus isolates produced 500 base pairs typical of Cucumber mosaic virus. The gene sequence analysis revealed that all the isolates had sequence homology of 95% and above with Cucumber mosaic virus (CMV) and are therefore considered strains of CMV. The results also showed that CMV isolates investigated in this study shared common ancestry, though belonging to different clusters. The results also indicated that CMV could be widespread and therefore a threat to C. moschata production in Itu and Uyo Local Government Areas of Akwa Ibom State. This is the first report of CMV infecting C. moschata in Akwa Ibom State, Nigeria. Further work should be carried out to cover the entire state.

Natural occurrence of cucumber mosaic virus infecting Adenium obesum plants in Brazil

AbstractIn 2022, virus‐like symptoms were observed in Adenium obesum plants in Brazil. High‐throughput sequencing analysis found three contig sequences of cucumber mosaic virus (CMV) genome segments, which were of 3352, 3006 and 2221 nucleotides, and shared 98.59%, 95.02% and 98.05% nucleotide identities with the nucleotide sequences of CMV RNAs 1, 2 and 3, respectively. Phylogenetic analysis of the coat protein gene indicated that the CMV isolate belongs to the subgroup IB. Symptoms of mottle like those observed in the field samples were reproduced on mechanically inoculated plants of A. obesum, and RT‐PCR confirmed the CMV infection. CMV was transmitted by Aphis gossypii to A. obesum plants. This is the first report of CMV infecting A. obesum plants in Brazil.

First report of cucumber mosaic virus infecting Azorina vidalii in Azores Islands.

Virus diseases that occur in crops pose a major threat not only to global food security but also to wild plant communities growing in natural ecosystems (Jones, 2020, and references therein). In Azores (Portugal) little is known about viruses present on native flora and therefore, they have not been taken into consideration in conservation programs. Considering this, we selected Azorina vidalii (Campanulaceae), an endangered (IUCN) plant, endemic to Azores (Bilz, 2011), to survey for plant viruses. A. vidalii, the sole species of its genus, is often found in crevices with no soil accumulation on coastal cliffs, exposed to storms and sea spray, and is used as an ornamental. Leaves from 53 plants of A. vidalii from three populations from Terceira Island and three populations from Flores Island were randomly collected without obvious symptoms of virus infection, between the summer of 2021 and fall of 2022. RNA extraction was performed using the Plant/Fungi Total RNA Purification Kit (Norgen Biotek, Canada). RNA extracts from each population were pooled into six distinct composite samples (AvT1, AvT2, AvT3, AvF1, AvF4 and AvF5) and sent to Lexogen (Austria) for small RNA library preparation and High-Throughput Sequencing. Single-end RNA sequencing using Illumina NextSeq2000 system yielded between 10.1 M and 33.8 M raw reads. Adaptors and low-quality reads were removed with Trim Galore! and PRINSEQ. Trimmed reads were mapped to the genome phylogenetically nearest to A. vidalii available at the NCBI database (Adenophora triphylla). The resulting 2.5 M - 13.5 M unmapped reads were analysed with VirusDetect online version (database v248) (Zheng et al., 2017) for virus detection and identification. Sequences of cucumber mosaic virus (CMV) (contigs of up to 3045 nt for RNA1, 2917 nt for RNA2 and 2086 nt for RNA3) were identified in five (AvT1, AvT2, AvT3, AvF1 and AvF5) of the six composite samples and CMV satellite sequences (two contigs with 145 and 197 nt) were identified in only one (AvT1) of the composite samples. To confirm the presence of CMV, all samples were tested by two-step RT-PCR using primers targeting CMV-specific RdRp gene (513 bp) (Grieco et al., 2000), which retrieved 18 positive samples (34%). Nine samples were selected for Sanger sequencing (six out of 13 from Terceira and three out of five from Flores) based on digestion profile obtained with AluI and MboI. The resulting sequences (OQ176229-OQ176233, OQ732757-OQ732760) share an identity of 97.2-100% and BLASTn showed them to have 98.3-99.6% identity to CMV strain TN (AB176848). A Neighbour-Joining tree (Supplementary material) inferred in MEGA11 (Tamura et al., 2021) with 237 additional CMV-RdRp sequences, showed that A. vidalii CMV-derived isolates clustered together with reference strains of subgroup II, as those used by Roossinck (2002) for phylogenetic analysis of the 2a ORF. Besides CMV, tomato spotted wilt virus and polerovirus-associated RNAs sequences were found in one of the A. vidalii populations, but with lower coverage, and need to be further investigated. To the best of our knowledge, this is the first report of CMV infecting A. vidalli. CMV, genus Cucumovirus, is an agriculturally important virus and one of the most successful viruses known, infecting over 1,200 species of plants (Palukaitis & García-Arenal, 2003). In addition to A. vidalii being a CMV reservoir, which may have implications on adjacent crop fields, further research is needed to investigate the impact of CMV on A. vidalli fitness.

Konya İli Park ve Ev Bahçelerinde Peyzaj Amaçlı Yetiştirilen Dahlia Türlerinde Enfeksiyon Yapan Bazı Virüs Hastalıklarının Serolojik Yöntemlerle Belirlenmesi

In this study, it was aimed to reveal some viruses that are a problem in Dahlia plants grown for ornamental plants in parks and home gardens in Selçuklu, Karatay and Meram districts of Konya. For this reason, in the 2019 summer, leaf samples were taken from 152 Dahlia plants showing symptoms similar to virus disease symptoms such as mosaic, deformations, yellowing, blight on the leaves and stunted plants. Possible infections of Cucumber mosaic virus (CMV), Tomato spotted-wilt virus (TSWV) and Impatiens necrotic spot virus, (INSV) on these leaves were tested by serological-based DAS-ELISA (Double Antibody Sandwich- Enzyme Linked Immuno Sorbent Assay) method. According to DAS-ELISA results, it was determined that 46.71% of the samples were infected with at least one of these three viruses. In addition, TSWV was detected as the most common virus with a 38.82% relative incidence in the samples, followed by CMV (27.63%). Mixed infections of the viruses were also detected in the leaf samples tested. As a result of the tests, only CMV + TSWV double infection was detected in a total of 30 samples. On the other hand, INSV infection was not detected in any of the leaf samples tested. As a result of survey studies, the average of prevalence rate of virus diseases in Dahlia plants grown in Konya was calculated as 69.56%. Moreover, it was determined that virus diseases were most common in Selçuklu district (75.47%). This is the first report of CMV and TSWV on Dahlia spp. in Türkiye.

Identification of Cucumber mosaic virus from Arisaema heterophyllum Blume in China.

Arisaema heterophyllum Blume is a valuable medicinal plant in the Araceae family. The dried tuber of A. heterophyllum is used in the traditional Chinese medicine, Rhizoma Arisaematis, which is used to treat convulsions, inflammation and cancer. In 2017, typical mosaic virus-like symptoms were observed in A. heterophyllum in Jilin province, China. To further identify the pathogens, we conducted RT-PCR using virus- and genus-specific primers to amplify partial genome sequences of Cucumber mosaic virus (CMV), Tobamovirus and Potyvirus, respectively. The CMV primers showed specific amplification, but the Tobamovirus and Potyvirus primers did not. We further cloned and sequenced the 2b, MP and CP genes of the CMV-Ah isolate. Phylogenetic analysis showed the CMV-Ah isolate belonged to subgroup IB. To our knowledge, this is the first report of CMV infecting A. heterophyllum in China. Keywords: Cucumber mosaic virus; Arisaema heterophyllum Blume; subgroup IB; phylogenetic analysis.

Serological and Molecular Characterisation of Cucumber mosaic virus Infecting Lagenaria siceraria L. in Adim, Biase L.G.A., Cross River State, Nigeria

Cucumber mosaic virus (CMV) is one of the most important viral pathogens infecting a wide range of plant species in Nigeria. Mosaic and mottle symptoms were observed on Lagenaria siceraria L. in Adim Southern-Nigeria in 2018 and the infected leaves collected for investigation. This research was aimed at characterising the virus responsible for this infection with a view to identifying it. Antigen coated plate (ACP) enzyme linked-immunosorbent assay (ELISA) and gene sequencing were employed methods in the characterisation process. The Amplified Complementary Deoxyribonucleic Acid (cDNA) was cloned and the nucleotide sequence was determined. Result of serology revealed that the virus belonged to the genus Cucumovirus while the gene sequence obtained when compared to known virus sequences present in the GenBank using the Basic Local Alignment Search Tool (BLAST) program available at National Centre for Biotechnology Information (NCBI) revealed 97% sequence homologue with Cucumber mosaic virus confirming it as Cucumber mosaic virus. This is the first report of CMV infecting L. siceraria in Nigeria. I recommend further studies on insect and host range test of this virus be carried on.

Molecular detection and first report of Cucumber mosaic virus infecting ‘Cavendish’ banana plants in Ethiopia

Cucumber mosaic virus (CMV) is one of the most important viral pathogen limiting banana production globally. The aim of the present study was to test the presence of CMV infection in banana plants from Ethiopia. Dot immune-binding assay and RT-PCR of symptomatic leaves could detect CMV in 92% and 100% of the samples, respectively. Direct sequencing of the PCR product produced 292 bp long nucleotide sequence showing 96.23–96.58% sequence identity at nucleotide level with isolates from Serbia (KT270566), Italy (KU976469), and others confirming CMV infection. The phylogenetic tree constructed at nucleotide level with MEGA 7.0 program revealed that the isolate belongs to subgroup IA. To the best of our knowledge, this is the first report of CMV infecting banana plants from Ethiopia.

First identification of cucumber mosaic virus in Prunus serrulata, Photinia serrulata, Begonia semperflorens and Osmanthus matsumuranus

Infection with cucumber mosaic virus (CMV) has resulted in important economic losses in many crops worldwide. In this study, CMV was detected from Prunus serrulata, Photinia serrulata, Begonia semperflorens and Osmanthus matsumuranus by RT-PCR and Western blot, when eleven kinds of horticultural plants from three provinces were screened. This is the first report of CMV naturally infecting these four species of horticultural plants. In addition, CMV isolates from southwest China presented regional differences to isolates from other parts of China based on phylogenetic analysis.

Characterisation of a subgroup IB isolate of Cucumber mosaic virus from Xanthosoma sp. in sub-Saharan Africa

Three tannia (Xanthosoma sp.) plants showing mosaic, mottling and vein chlorosis symptoms were observed in Buikwe district, Uganda. Next generation sequencing (NGS) of RNA extracted from the three plants revealed the presence of Cucumber mosaic virus (CMV). The complete genome sequence of this isolate, designated CMV-Xa, was assembled and sequence analyses based on the three genomic RNAs revealed that CMV–Xa belongs to subgroup IB. This is the first report of CMV infecting Xanthosoma sp. and also the first CMV isolate from subgroup IB detected from sub-Saharan Africa.

First Report of Cucumber mosaic virus Infecting Siam Tulip (Curcuma alismatifolia) in Florida

Siam tulip (Curcuma alismatifolia) has become an important crop for breeding new varieties owing to its high economic value as a tropical ornamental. In September 2017, C. alismatifolia potted plants, originally from Alachua, FL, were submitted to the Florida Department of Agriculture and Consumer Services, Division of Plant Industry, Gainesville, FL, for identification. The plants exhibited petal and bract necrosis. Initial serological testing for the presence of cucumber mosaic virus (CMV) using ELISA yielded positive results. To confirm pathogen identification, a two-step quantitative reverse transcription PCR, using primers targeting CMV-specific coat protein (amplicon of ∼450 bp), was performed. The PCR product, GenBank accession MG652768, had 99% nucleotide identity with CMV isolates in GenBank. Although all the tissues tested positive for CMV, it is unknown whether the necrotic symptoms were solely owing to CMV infection. CMV is known to infect a wide variety of plants in the ginger family, but to our knowledge, this is the first report of CMV in C. alismatifolia.

First identification of cucumber mosaic virus infecting six fruit crops in China

Cucumber mosaic virus (CMV) has an extensive host range, however there are few reports of CMV infecting fruit crops in China. In this study, CMV was detected using RT-PCR and Western blot from six kinds of fruit crops including pear in Heilongjiang province, apricot, grape, peach, Castanea mollissima and Malus spectabilis in Shandong province in China. This is the first report of CMV naturally infecting these six fruit crops in China. In addition, this is also the first report of CMV in Heilongjiang province which is the northest province of China.

Yellowing of Panax ginseng Meyer induced by cucumber mosaic virus infection

Yellowing and slight stunting were found on ginseng (Panax ginseng) plants in Fukushima Prefecture, Japan, in August 2017. Cucumber mosaic virus (CMV) isolated from the diseased leaves reproduced the symptoms after back-inoculation to ginseng plants, and CMV was detected from the inoculated symptomatic leaves. Isolated CMV was classified into subgroup IA based on the coat protein and 5′ NTR nucleotide sequencing analyses. This is the first report of CMV as a pathogen of ginseng in Japan.

Cucumber mosaic virus infecting ‘Cavendish’ banana in Argentina

Banana plants (Musa sp.) showing severe mosaic symptoms in leaves were observed in Laguna Naineck, Formosa, Argentina. Electron microscopy observations of leaf dip preparations revealed isometric particles ca. 30 nm in diameter, which were identified as cucumber mosaic virus (CMV) by enzyme-linked immunosorbent assay (ELISA) test and reverse transcription-polymerase chain reaction (RT-PCR). CMV was mechanically transmitted to healthy Nicotiana glutinosa plants. Sequence analysis of coat protein gene showed highest nucleotides identity with other CMV isolates from United States of America, Serbia, Russia, Democratic Republic of Congo, Iran and Brazil, ranging between 96.9–98.3%. Phylogenetic analysis indicated that the virus isolate named Laguna Naineck (MH716245) belongs to the CMV group IA. To our knowledge, this is the first report of CMV in banana in Argentina. Moreover, constitutes the first Argentine CMV isolate available in the international nucleotide sequence databases.

First Report of Mosaic Disease caused by Cucumber mosaic virus Infecting Passion Fruit in Ecuador

HomePlant DiseaseVol. 102, No. 2First Report of Mosaic Disease caused by Cucumber mosaic virus Infecting Passion Fruit in Ecuador PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Mosaic Disease caused by Cucumber mosaic virus Infecting Passion Fruit in EcuadorS. Yeturu, L. Paz, D. Intriago, J. Castro, H. Álvarez, and W. VieraS. YeturuSearch for more papers by this author, L. PazSearch for more papers by this author, D. IntriagoSearch for more papers by this author, J. CastroSearch for more papers by this author, H. ÁlvarezSearch for more papers by this author, and W. Viera†Corresponding author: W. Viera; E-mail: E-mail Address: william.viera@iniap.gob.ecSearch for more papers by this authorAffiliationsAuthors and Affiliations S. Yeturu , National Institute of Agricultural Research, Fruit Program, Quito, Ecuador L. Paz D. Intriago , National Institute of Agricultura Research, Plant Protection Department, Yaguachi, Ecuador J. Castro , National Institute of Agricultural Research, Fruit Program, Mocache, Ecuador H. Álvarez , National Institute of Agricultural Research, Fruit Program, Portoviejo, Ecuador W. Viera † , National Institute of Agricultural Research, Fruit Program, Quito, Ecuador. Published Online:7 Dec 2017https://doi.org/10.1094/PDIS-06-17-0814-PDNAboutSectionsSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Passion fruit (Passiflora edulis) is a native of tropical America and is cultivated throughout tropical and subtropical regions around the world. It belongs to the family Passifloraceae and is commonly known as yellow passion fruit, maracuyá, yellow granadilia, and pommelianejaume (Sunitha and Devaki 2009). Ecuador is the main exporter of maracuyá pulp in the world. It is grown in an area of 13,389 ha, with a production of 58,522 t (MAGAP 2016). During September 2015, mosaic, blistering, curling, and necrosis symptoms were seen on passion fruit plants in Quevedo, Los Ríos, Ecuador. Ten seedlings of Cucurbita pepo (squash) were inoculated with sap from symptomatic passion fruit leaves using 0.01 M phosphate buffer (pH 7.0). Vein clearing and blistering symptoms were observed 11 days post inoculation (dpi). Field-infected and sap-inoculated passion fruit and C. pepo samples showed positive reactions against Cucumber mosaic virus (CMV) polyclonal antibodies using TAS-ELISA (Agdia, U.S.A.). The sap-inoculated passion fruit leaves were also positive for CMV in TAS-ELISA. Total RNA was isolated from a field-infected passion fruit leaf sample using Trizol (Sigma). In reverse transcription (RT)-PCR, a DNA fragment of ∼500 bp was amplified using specific primers for the coat protein (CP) gene of CMV (Liu et al. 2012). The amplicon was sequenced and deposited in NCBI GenBank (accession no. KX470408). Sequence comparison (BioEdit v. 7.05) of the CP gene of the Ecuadorian isolate with other CMV isolates (KT302171-China, DQ302719-China, AJ585521-Australia, FJ403473-China, JN559384-China, EU250361-Taiwan, EF213025-China, AJ871492-Taiwan, AF368192-China, KC527745-South Korea, GU111229-India, AJ829779-Spain, KR535607-South Korea, AF418577-Brazil, KU144674-Mexico, GU453918-U.S.A., AY429432-China, and FN257306-Italy) showed maximum identity of 99.4% at the nucleotide level and 99.1% identity at the amino acid level with KT302171-China. CMV belongs to the genus Cucumovirus and family Bromoviridae. It is transmitted by aphids in a nonpersistent manner and has a wide host range that includes over 1,200 species belonging to 100 plant families. CMV causes significant economic losses in vegetable crops, horticulture crops, and weed plants (Zitter and Murphy 2009). To our knowledge, this is the first report of CMV on passion fruit in Ecuador.

CHARACTERIZATION OF A SUBGROUP II ISOLATE OF CUCUMBER MOSAIC VIRUS FROM BITTER GOURD IN CHINA

Diseased bitter gourd plants with severe leaf rolling symptoms were observed in Sichuan province (southwest China). Leaf dips-prepared from symptomatic leaves contained particles ca. 30 nm in diameter. The virus recovered from all samples was identified as Cucumber mosaic virus (CMV) by Western blotting, RT-PCR and sequencing of amplicons. All obtained sequences were identical, and the virus isolate was designated SC-J1. The complete nucleotide sequence of the CP (GenBank accession No. KT932936) of the isolate shared 99% identity to the corresponding regions of strain Hnt (CMV II). Phylogenetic analysis based on the nucleic acid sequence of the CP shows that SC-J1 belongs to CMV subgroup II. To our knowledge, this is the first report of CMV II infecting bitter gourd in China.

FIRST REPORT OF CUCUMBER MOSAIC VIRUS IN ANEMONE sp. IN GREECE

Virus-like symptoms, such as severe stunting and mosaic, were observed in a greenhouse-grown Anemone sp. (cv. Jerusalem), in Pella (northern Greece) in January 2014. Foliar samples were collected from 20 symptomatic and five symptomless plants and subjected to three initial tests: (i) DAS-ELISA to check for the presence of Cucumber mosaic virus (CMV), (ii) RT-PCR using generic primers for the detection of potyviruses (Pappu et al., 1993) and (iii) PCR for phytoplasmas (Gundersen and Lee, 1996). CMV was detected in all symptomatic plants but i n none of the asymptomatic ones, whereas PCR-based tests for potyviruses or phytoplasmas resulted negative. In order to verify the results of serological tests, a nested RT-PCR was performed on total RNA extracts from all 25 samples. Degenerate primers CMVup624a (5′- ATGGACAAATCTGRATC-3′) and CMVdo1244a (5′- TGRTGCTCRAYGTCKACATGA-3′), used in the first round of PCR were followed by the set CMVup624b (5′- GGACAAATCTGRATCTCCCAATGC-3′) and CMVdo1244b (5′- TGCTCRAYGTCRACATGAAG-3′), designed to amplify a 622 nt- long fragment of the viral coat protein gene. A mplicons of t h e expected size were obtained from all the symptomatic samples but not from the asymptomatic ones. Sequencing of two randomly chosen PCR products (GenBank accession Nos LN810056, LN810057) showed 99% nucleotide identity with CMV isolates from various hosts (KC763473, EU191027). Phylogenetic analyses showed that studied CMV isolates from Anemone sp. belong to sub-Group II. Finally, CMV was mechanically transmitted from the original symptomatic plants onto Cucurbita pepo and Nicotiana benthamiana, and its presence was confirmed by DAS-ELISA. To our knowledge this is the first report of CMV in Anemone sp. in Greece.

First report of Cucumber mosaic virus infecting watermelon in Greece and Bulgaria

In 2014, a total of 108 symptomatic watermelon samples were collected in Greece and analyzed by DAS-ELISA using polyclonal antisera (INRA, Montfavet) against the most common aphid-transmitted viruses. Cucumber mosaic virus (CMV) was detected in eight of 108 plants tested. Five of these plants collected at Lesvos were also infected with Watermelon mosaic virus (WMV), whereas three plants from Prohoma had single infections. Five samples with severe stunting and yellowing collected at Asenovgrad (Bulgaria) in 2013 and tested by DAS-ELISA for the above viruses hosted CMV and Cucurbit aphid-borne yellows virus (CABYV). To confirm CMV presence in watermelon, a nested RT-PCR assay was carried out first with the degenerated primers CMVup624a (5′-ATGGACAAATCTGRATC- 3′) and CMVdo1244a (5′-TGRTGCTCRAYGTCKACATGA-3′) followed by CMVup624b (5′-GGACAAA TCTGRA TCTCCCAA TGC-3′) and CMVdo1244b (5′- TGCTCRAYGTCRACATGAAG-3′) that amplify a 622 bp region from the viral coat protein gene. Total RNA (Chatzinasiou et al., 2010, method A) extracted from all ELISA- positive watermelon samples from both countries and from two healthy watermelon plants was used as template in nested RT-PCR. A product of the expected size was amplified from all serologically CMV-positive samples, but not from the healthy ones. The Greek CMV isolates from Lesvos (LN810059) and Prohoma (LN810060) showed 99% nucleotide sequence identity with potato (AB448694) and tomato (EF153734) CMV isolates from Syria and India, while the Bulgarian isolate (LN810058) showed 99% nucleotide sequence identity with an Indian cucumber isolate (JF279608). Phylogenetic analysis indicated that the Greek CMV isolate (LN810059) belongs to sub-group IA, while the Bulgarian isolate and a Greek isolate (LN810060) belong to sub-group IB. To our knowledge this is the first report of CMV infecting watermelons in Greece and Bulgaria.

FIRST REPORT OF CUCUMBER MOSAIC VIRUS AND OLIVE LATENT RINGSPOT VIRUS ON OLIVE TREES IN LEBANON

Olive (Olea europea L.) is cultivated in Lebanon on a surface of ca.53.600 ha, accounting for 43% of the area given over to perennial crops (Anonymous, 2010). Olive trees are affected by a number of virus and virus-like agents that persist in propagating material, with which they can be transmitted and disseminated (Martelli, 2011). Twelve trees of cv. Airouni, which is one of the most important cultivars grown in the country, were sampled in northern Lebanon and assayed for determining their sanitary status, in view of their possible use by nurseries for propagation. No symptoms of putative viral origin were observed in the surveyed orchards. Leaf samples were tested by RT-PCR to assess the presence of viruses commonly found in olive, i.e. Arabis mosaic virus (ArMV), Cherry leaf roll virus (CLRV), Cucumber mosaic virus (CMV), Olive latent ringspot virus (OLRSV), Olive latent virus 1 (OLV-1), Olive latent virus 2 (OLV-2), Olive leaf yellowing-associated virus (OLYaV) and Strawberry latent ringspot virus (SLRSV), using the protocol and the sets of specific primers reported by Grieco et al. (2000). Results showed that CLRV, OLV-1, OLV-2 and OLYaV are present in nine trees, whereas ArMV and SLRV were not found. Two samples were positive for CMV and OLRSV, yielding the expected amplified products of 513 bp and 492 bp, respectively. Both these viruses were mechanically transmitted to herbaceous hosts (Cucumis sativus and Chenopodium quinoa, respectively) and their presence in these hosts was ascertained by RT-PCR. One of the trees proved free from all viruses and may constitute a source of virus-tested material for propagation. To our knowledge, this is the first report of CMV and OLRSV in olive in Lebanon.

First Report of Cucumber mosaic virus Infecting Chinese Mallow in China

The virus in naturally infected, stunted Chinese mallow plants and mosaic leaves was identified as Cucumber mosaic virus (CMV). Six symptomatic plants and one symptomless plant were collected in Chongqing, China. DAS-ELISA suggested CMV was likely associated with the diseased Chinese mallow. Double-stranded RNA was extracted from the samples, analysed by RT-PCR, and the coding sequences of their coat proteins (CPs) were sequenced. The results further confirmed CMV was the pathogen causing Chinese mallow stunted, mosaic disease. The isolate was named CMV-DXC. The full sequence of CMV-DXC CP was determined, and it had the highest nucleotide identity (99.4%) of those of CMV-lily, CMV-WSJ and CMV-Hnt, respectively. Phylogenetic analysis shows that CMV-DXC belongs to CMV subgroup II. To our knowledge, this is the first report of CMV infecting Chinese mallow in China.

First Report of Cucumber mosaic virus Isolated from Wild Vigna angularis var. nipponensis in Korea.

A viral disease causing severe mosaic, necrotic, and yellow symptoms on Vigna angularis var. nipponensis was prevalent around Suwon area in Korea. The causal virus was characterized as Cucumber mosaic virus (CMV) on the basis of biological and nucleotide sequence properties of RNAs 1, 2 and 3 and named as CMV-wVa. CMV-wVa isolate caused mosaic symptoms on indicator plants, Nicotiana tabacum cv. Xanthi-nc, Petunia hybrida, and Cucumis sativus. Strikingly, CMV-wVa induced severe mosaic and malformation on Cucurbita pepo, and Solanum lycopersicum. Moreover, it caused necrotic or mosaic symptoms on V. angularis and V. radiate of Fabaceae. Symptoms of necrotic local or pin point were observed on inoculated leaves of V. unguiculata, Vicia fava, Pisum sativum and Phaseolus vulgaris. However, CMV-wVa isolate failed to infect in Glycine max cvs. ‘Sorok’, ‘Sodam’ and ‘Somyeong’. To assess genetic variation between CMV-wVa and the other known CMV isolates, phylogenetic analysis using 16 complete nucleotide sequences of CMV RNA1, RNA2, and RNA3 including CMV-wVa was performed. CMV-wVa was more closely related to CMV isolates belonging to CMV subgroup I showing about 85.1–100% nucleotide sequences identity to those of subgroup I isolates. This is the first report of CMV as the causal virus infecting wild Vigna angularis var. nipponensis in Korea.