scholarly journals First Report of Cucumber mosaic virus in Saintpaulia ionantha in Korea

Plant Disease ◽  
2014 ◽  
Vol 98 (4) ◽  
pp. 573-573 ◽  
Author(s):  
J. Y. Yoon ◽  
G. S. Choi ◽  
I. S. Cho ◽  
S. K. Choi

African violet (Saintpaulia ionantha) is an ornamental species of the family Gesneriaceae and is characterized by fleshy leaves and colorful flowers. This popular, exotic ornamental, originally from Kenya and Tanzania, is vegetatively produced from cutting and tissue culture (1). In May 2013, virus-like foliar symptoms, including a mosaic with dark green islands and chlorosis surrounding the veins, were observed on an African violet plant in a greenhouse located in Icheon, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with a commercial immunostrip kit (Agdia, Elkhart, IN). The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-AV1) caused necrotic local lesions on Chenopodium amaranticolor at 5 days post-inoculation (dpi), while mild to severe mosaic was observed in Nicotiana glutinosa, N. tabacum ‘Samsun NN,’ Cucurbita pepo ‘Super-Top,’ Physalis angulate, and Solanum lycopersicum ‘Unicorn’ 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions ∼28 nm in diameter, respectively. To verify whether CMV-AV1 is the cause of disease symptoms observed in African violet, virus-free African violet (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-AV1. At 8 weeks after inoculation, all plants produced systemic mosaic and chlorosis surrounding veins, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated African violet plants remained symptomless and virus-free. The presence of CMV-AV1 in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany), according to the manufacturer's instructions. RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CPTALL3 and CPTALL5 (2), amplifying the entire CP gene and part of an intergenic region and 3′-noncoding region of CMV RNA3. RT-PCR products (960 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen) and sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-AV1 CP sequence (Accession No. AB842275) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-AV1 infection. CMV may pose a major threat for production of African violet since the farming of African violet plants is performed using the vegetative propagation of the African violet leaves in Korea. In particular, mosaic and chlorosis symptoms in African violet cause damage to ornamental quality of African violet. To our knowledge, this is the first report of CMV infection of African violet in the world. References: (1) S. T. Baatvik. Fragm. Flor. Geobot. Suppl. 2:97, 1993. (2) S. K. Choi et al. J. Virol. Methods 83:67, 1999.

Plant Disease ◽  
2014 ◽  
Vol 98 (9) ◽  
pp. 1283-1283
Author(s):  
S.-K. Choi ◽  
I.-S. Cho ◽  
G.-S. Choi ◽  
J.-Y. Yoon

Catharanthus roseus, commonly known as Madagascar rosy periwinkle (also called vinca), is a tropical perennial herb of the family Apocyanaceae. Periwinkle is a bedding plant widely used in Korea because of its drought tolerance, low maintenance, and varied flower colors. In May 2013, virus-like foliar symptoms, including a mosaic with malformation of leaves, were observed on a periwinkle plant in a greenhouse located in Chonbuk Province, Korea. Cucumber mosaic virus (CMV) was identified in the symptomatic plant by serological testing for the presence of CMV coat protein (CP) with an immune-strip kit developed by our laboratory. The presence of CMV was confirmed by serological detection with a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia, Elkhart, IN). Sap from the serologically positive sample was mechanically inoculated to test plants using 10 mM phosphate buffer (pH 7.0). The virus (named CMV-Vin) caused necrotic local lesions on Chenopodium amaranticolor at 5 days-post-inoculation (dpi), while mild to severe mosaic was observed in Capsicum annuum, Cucumis sativus, Cucurbita pepo ‘Cheonggobong,’ Nicotiana glutinosa, N. tabacum‘Samsun NN,’ Physalis angulate, and Solanum lycopersicum ‘Pink-Top’ 10 to 14 dpi. Examination of the inoculated plant leaves by DAS-ELISA and electron microscopy (leaf dips) showed positive reactions to CMV and the presence of spherical virions ~28 nm in diameter, respectively. To verify whether CMV was the causal agent for the disease symptoms observed in naturally infected periwinkle, virus-free periwinkle (10 plants) was mechanically inoculated by sap from local lesions on C. amaranticolor inoculated with CMV-Vin. At 6 weeks after inoculation, all plants produced systemic mosaic and distortion of leaves, resulting in strong DAS-ELISA reactions for CMV, whereas mock-inoculated periwinkle plants remained symptomless and virus-free. The presence of CMV-Vin in all naturally infected and mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with a RNeasy Plant Mini Kit (Qiagen, Valencia, CA) and RT-PCR was carried out with the One-Step RT-PCR Kit (Invitrogen, Carlsbad, CA) using a pair of primers, CMVCPFor and CMVCPRev (1), which amplified the entire CP gene. RT-PCR products (657 bp) were obtained from all naturally infected and mechanically inoculated plants as well as from a positive control (viral RNAs from virions), but not from healthy tissues. The amplified RT-PCR products were directly sequenced using BigDye Termination kit (Applied Biosystems, Foster City, CA). Multiple alignment of the CMV-Vin CP sequence (Accession No. AB910598) with CP sequences of other CMV isolates using MEGA5 software revealed that 91.8 to 99.0% and 71.0 to 73.0% identities to those of CMV subgroup I and subgroup II, respectively. These results provide additional confirmation of CMV-Vin infection. Being perennial, periwinkle plants could serve as a reservoir for CMV to infect other ornamentals and cultivated crops (2). To our knowledge, this is the first report of CMV infection on periwinkle in Korea. References: (1) S. K. Choi et al. Virus Res. 158:271, 2011. (2) P. Palukaitis et al. Adv. Virus. Res. 41:281, 1992.


Plant Disease ◽  
2007 ◽  
Vol 91 (3) ◽  
pp. 322-322 ◽  
Author(s):  
L. Cardin ◽  
J. P. Onesto ◽  
I. Bornard ◽  
B. Moury

Phlox paniculata L., a perennial plant from the family Polemoniaceae, is cultivated as an ornamental in gardens and for cut-flower production. In spring 2003, two types of symptoms were observed in P. paniculata plants grown for cut flowers on a farm in the Var department, France. Some plants showed a mild leaf mosaic while others showed leaf browning and delayed growth. In plants showing mild mosaic, Cucumber mosaic virus (CMV) was detected on the basis of the symptoms exhibited by a range of inoculated plants, the observation of isometric particles (approximately 30 nm) with the electron microscope in crude sap preparations from the infected plants, and the positive reaction in double-antibody sandwich (DAS)-ELISA to polyclonal antibodies raised against CMV (1). In double-immunodiffusion analysis, the five tested isolates were shown to belong to group II of CMV strains. To determine if CMV was responsible for the symptoms observed, one isolate was multiplied in Nicotiana tabacum cv. Xanthi-nc plants after isolation from local lesions on Vigna unguiculata and mechanically inoculated to 12 1-year-old P. paniculata plants. At 3 months post inoculation (mpi), all plants showed mild mosaic and CMV was detected by DAS-ELISA. In sap preparations from P. paniculata plants showing leaf browning symptoms, rod-shaped particles with two distinct sizes of 190 to 210 and 70 to 90 nm long, typical of those associated with tobraviruses, were revealed using electron microscopy. Local lesions typical of Tobacco rattle virus (TRV) were observed after inoculation of N. tabacum cv. Xanthi-nc, Chenopodium amaranticolor, and C. quinoa. Total nucleic acid preparations were prepared from symptomatic plants, and amplicons of the expected size (463 bp) were generated by reverse-transcription (RT)-PCR using primers specific to TRV RNA 1 (4). The nucleotide sequence of one amplicon was 93.6% identical to the sequence of a reference TRV isolate (GenBank Accession No. AJ586803). Twelve 1-year-old P. paniculata plants were mechanically inoculated with an extract of infected tissues from one symptomatic P. paniculata plant. TRV was detected 2 to 6 mpi in apical leaves of all inoculated plants by RT-PCR, although the plants did not express symptoms. Since no other pathogens were detected in the source plants, it is plausible that the lack of symptoms in back-inoculated plants is either due to a long incubation period or an interaction with particular environmental factors such as cold conditions. The survey of approximately 200 plants revealed that approximately 7, 10, and 1% were infected by TRV, CMV, or by both viruses, respectively. CMV and TRV were previously detected in P. paniculata in Latvian SSR and in Lithuania (2,3). These results show that sanitary selection of P. paniculata prior to vegetative propagation should include a screening for TRV and CMV infections. References: (1) J.-C. Devergne et al. Ann. Phytopathol. 10:233, 1978. (2) Y. Ignab and A. Putnaergle. Tr. Latv. S.-Kh. Akad. 118:27, 1977. (3) M. Navalinskiene and M. Samuitiene. Biologija 1:52, 1996. (4) D. J. Robinson. J. Virol. Methods 40:57, 1992.


Plant Disease ◽  
2014 ◽  
Vol 98 (4) ◽  
pp. 574-574 ◽  
Author(s):  
Y. F. Wang ◽  
G. P. Wang ◽  
L. P. Wang ◽  
N. Hong

Taro (Colocasia esculenta L. Schott) is an important crop worldwide. In China, the growing area and productivity of taro increased greatly in recent years. During the 2010 to 2013 growing seasons (from May to July), the incidence of Cucumber mosaic virus (CMV) in taro was determined. Leaf samples from 91 taro plants, including 26 plants of cv. Hongyayu grown in Jiangxi Province in eastern China, 33 plants of cv. Eyu no.1 grown in Hubei Province in central China, and 32 plants of cv. Baiyu grown in Guangxi Province in southwest China were collected randomly and tested for the presence of CMV by reverse transcription (RT)-PCR. Some sampled plants of cv. Hongyayu and Eyu no.1 showed leaf chlorosis or chlorotic spots, and most of the plants of these three cultivars showed feather-like mosaic symptom on their leaves, which was confirmed to be associated with the infection of Dasheen mosaic virus (DsMV) in our previous studies (3). Total RNA was extracted from leaves using CTAB protocol reported by Li et al. (1). Primer set forward 5′-ATGGACAAATCTGAATCAACC-3′/reverse 5′-TAAGCTGGATGGACAACCCGT-3′ (4) was used for the amplification of a 777-bp fragment, which contains the complete capsid protein (CP) gene of 657 bp. PCR products of the expected size were identified from 11 taro samples, including two samples of Hongyayu, three Eyu no.1, and six Baiyu plants. The result did not show any specific association between the symptoms observed and CMV infection. The obtained PCR products were cloned individually into the vector pMD18-T (TaKaRa, Dalian, China). Three independent clones derived from each product were sequenced by Genscript Corp., Nanjing, China. Pairwise comparison of CP gene sequences (Accession No. of one representation CP sequence: KF564789) showed 99.7 to 99.8% nucleotide (nt) and 99.1 to 99.5% deduced amino acid (aa) sequence identity among themselves, and 92.0 to 94.3% and 76.5 to 77.7% nt identities with corresponding sequences of CMV isolates in subgroup I and subgroup II (2), respectively. The maximum likelihood phylogenetic trees of nt and aa sequences generated by Clustal X v1.8 revealed that all these CMV isolates from taro in China fell into subgroup I. To further confirm the CMV infection, leaf saps of CMV infected taro plants of cv. Eyu no.1 were mechanically inoculated onto Pinellia ternate and Cucumis sativus. Plants of P. ternate showed local chlorotic lesions on the inoculated leaves and downward curl of newly grown leaves, and C. sativus showed local chlorotic lesions on the inoculated leaves and crinkle of newly grown leaves at 10 to 15 days post inoculation. The RT-PCR detection confirmed the CMV infection in those inoculated plants, and that the plants of P. ternate were also positive to DsMV, further complementing the results obtained above. To our knowledge, this is the first report of CMV occurrence in taro plants grown in China. Our results indicated that taro plants were widely infected by CMV isolates in subgroup I. This study provides important information for further evaluating the viral sanitary status of taro germplasm and improving the certification program of taro propagation materials in China. References: (1) R. Li et al. J. Virol. Methods 154:48, 2008. (2) P. Palukaitis et al. Adv. Virus. Res. 62:241, 2003. (3) S. M. Shi et al. Acta Hortic. Sin. 39:509, 2012. (4) P. D. Xu et al. Chinese J. Virol. 15:164, 1999.


Plant Disease ◽  
2014 ◽  
Vol 98 (10) ◽  
pp. 1449-1449 ◽  
Author(s):  
K. Milojević ◽  
I. Stanković ◽  
A. Vučurović ◽  
D. Nikolić ◽  
D. Ristić ◽  
...  

Tulips (Tulipa sp. L.), popular spring-blooming perennials in the Liliaceae family, are one of the most important ornamental bulbous plants, which have been cultivated for cut flower, potted plant, garden plant, and for landscaping. In May 2013, during a survey to determine the presence of Cucumber mosaic virus (CMV, Cucumovirus, Bromoviridae) on ornamentals in Serbia, virus-like symptoms, including the presence of bright streaks, stripe and distortion of leaves, and reduced growth and flower size, were observed in an open field tulip production in the Krnjaca locality (a district of Belgrade, Serbia). Disease incidence was estimated at 20%. Symptomatic tulip plants were collected and tested for the presence of CMV by double-antibody sandwich (DAS)-ELISA using commercial diagnostic kit (Bioreba, AG, Reinach, Switzerland). Commercial positive and negative controls were included in each ELISA. Of the six tulip plants tested, all were positive for CMV. In bioassay, five plants of each Chenopodium quinoa, Nicotiana tabacum ‘Samsun,’ and N. glutinosa were mechanically inoculated with sap from selected ELISA-positive sample (79-13) using 0.01 M phosphate buffer (pH 7). Chlorotic local lesions on C. quinoa, and severe mosaic and leaf malformations on N. tabacum ‘Samsun’ and N. glutinosa, were observed 5 and 14 days post-inoculation, respectively. All mechanically inoculated plants were positive for CMV in DAS-ELISA testing. For further confirmation of CMV presence in tulip, total RNAs from all ELISA-positive symptomatic tulip plants were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). Reverse transcription (RT)-PCR was performed with the One-Step RT-PCR Kit (Qiagen) using specific primer pair CMVCPfwd and CMVCPrev (1), which flank conserved fragment of the RNA3 including the entire coat protein (CP) gene and part of 3′- and 5′-UTRs. Total RNAs obtained from the Serbian watermelon CMV isolate (GenBank Accession No. JX280942) and healthy tulip leaves served as the positive and negative controls, respectively. The RT-PCR products of 871 bp were obtained from all six samples that were serologically positive to CMV, as well as from the positive control. No amplicon was recorded in the healthy control. The amplified product which derived from isolate 79-13 was purified (QIAquick PCR Purification Kit, Qiagen), directly sequenced in both directions using the same primer pair as in RT-PCR, deposited in GenBank (KJ854451), and analyzed by MEGA5 software (4). Sequence comparison of the complete CP gene (657 nt) revealed that the Serbian isolate 79-13 shared the highest nucleotide identity of 99.2% (99% amino acid identity) with CMV isolates from Japan (AB006813) and the United States (S70105). To our knowledge, this is the first report on the occurrence of CMV causing mosaic on Tulipa sp. in Serbia. Taking into account vegetative reproduction of tulips and the large scale of international trade with tulip seeding material, as well as wide host range of CMV including a variety of ornamentals (2,3), this is a very important discovery representing a serious threat for the floriculture industry in Serbia. References: (1) K. Milojević et al. Plant Dis. 96:1706, 2012. (2) M. Samuitienė and M. Navalinskienė. Zemdirbyste-Agriculture 95:135, 2008. (3) D. Sochacki. J. Hortic. Res. 21:5, 2013. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.


Plant Disease ◽  
2014 ◽  
Vol 98 (9) ◽  
pp. 1284-1284 ◽  
Author(s):  
G. Parrella ◽  
B. Greco

Yucca aloifolia L. (Spanish bayonet), family Asparagaceae, is the type species of the genus Yucca. It is native to Mexico and the West Indies and is appreciated worldwide as an ornamental plant. In 2013, during a survey for viruses in ornamental plants in the Campania region of southern Italy, symptoms consisting of bright chlorotic spots and ring spots 1 to 3 mm in diameter with some necrotic streaks were observed on leaves of two plants of Y. aloifolia growing in a nursery located in the Pignataro Maggiore municipality, Caserta Province. Cucumber mosaic virus (CMV) infection was suspected because the symptoms resembled those caused by CMV in Yucca flaccida (1). A range of herbal plant indicators was inoculated with sap extracts of symptomatic Y. aloifolia plants and developed symptoms indicative of CMV. Furthermore, 30 nm isometric virus particles were observed in the same Y. aloifolia sap extracts by transmission electron microscopy. The identity of the virus was confirmed by positive reaction in ELISA tests with CMV polyclonal antisera (Bioreba) conducted on sap extracts of symptomatic Y. aloifolia plants and systemically infected symptomatic hosts (i.e., Nicotiana tabacum, N. glutinosa, Cucumber sativus cv. Marketer, Solanum lycopersicum cv. San Marzano). The presence of CMV in the two naturally infected Y. aloifolia and other mechanically inoculated plants was further verified by reverse transcription (RT)-PCR. Total RNAs were extracted with the E.Z.N.A. Plant RNA Kit (Omega Bio-Tek), according to the manufacturer's instructions. RT-PCR was carried out with the ImProm-II Reverse Transcription System first-strand synthesis reaction (Promega) using the primer pair CMV1 and CMV2 (2). These primers amplify part of the CP gene and part of the 3′-noncoding region of CMV RNA3 and were designed to produce amplicons of different sizes to distinguish CMV isolates belonging to subgroups I or II (3). RT-PCR products were obtained from both naturally infected Y. aloifolia and mechanically inoculated plants as well as from PAE1 isolate of CMV (2), used as positive control, but not from healthy plants. Based on the length of the amplicons obtained (487 bp), the CMV isolate from Y. aloifolia (named YAL) belonged to subgroup I (3). The amplified RT-PCR products were purified with QIAquick PCR Purification Kit (Qiagen), cloned in the pGEMT vector (Promega), and three independent clones were sequenced at MWG (Ebersberg, Germany). Sequences obtained from the two CMV-infected Y. aloifolia plants were identical. This sequence was deposited at GenBank (Accession No. HG965199). Multiple alignments of the YAL sequence with sequences of other CMV isolates using MEGA5 software revealed highest percentage of identity (98.9%) with the isolates Z (AB369269) and SO (AF103992) from Korea and Japan, respectively. Moreover, the YAL isolate was identified as belonging to subgroup IA, based on the presence of only one HpaII restriction site in the 487-bp sequence, as previously proposed (2). Although CMV seems to not be a major threat currently for the production of Y. aloifolia, because the farming of this plant is performed using vegetative propagation, particular attention should be given to the presence of the virus in donor mother plants in order to avoid the dispersion of infected plants that could serve as sources for aphid transmission to other susceptible plant species. To our knowledge, this is the first report of CMV infection of Y. aloifolia in the world. References: (1) I. Bouwen et al. Neth. J. Plant Pathol. 84:175, 1978. (2) G. Parrella and D. Sorrentino. J. Phytopathol. 157:762, 2009. (3) Z. Singh et al. Plant Dis. 79:713, 1995.


Plant Disease ◽  
2014 ◽  
Vol 98 (7) ◽  
pp. 1016-1016 ◽  
Author(s):  
B. Babu ◽  
H. Dankers ◽  
M. L. Paret

Scotch bonnet (Capsicum chinense) is a tropical hot pepper variety that is grown in South America, the Caribbean Islands, and in Florida, and is an important cash crop. In Florida, scotch bonnet is grown on ~100 acres annually. Virus-like leaf symptoms including mosaic and yellow mottling were observed on scotch bonnet plants in a field at Quincy, FL, with a disease incidence of ~5%. Two symptomatic and one non-symptomatic plant sample were collected from this field for identification of the causal agent associated with the symptoms. Viral inclusion assays (2) of the epidermal tissues of the symptomatic scotch bonnet samples using Azure A stain indicated the presence of spherical aggregates of crystalline inclusion bodies. Testing of the symptomatic samples using lateral flow immunoassays (Immunostrips, Agdia, Elkhart, IN) specific to Cucumber mosaic virus (CMV), Potato virus Y (PVY), Pepper mild mottle virus (PMMoV), Tobacco mosaic virus (TMV), Zucchini yellow mosaic virus (ZYMV), and Papaya ringspot virus (PRSV), showed a positive reaction only to CMV. The sap from an infected leaf sample ground in 0.01 M Sorensons phosphate buffer (pH 7.0) was used to mechanically inoculate one healthy scotch bonnet plant (tested negative for CMV with Immunostrip) at the 2- to 3-leaf stage. The inoculated plant developed mild mosaic and mottling symptoms 12 to 14 days post inoculation. The presence of CMV in the mechanically inoculated plant was further verified using CMV Immunostrips. Total RNA was extracted (RNeasy Plant Mini Kit, Qiagen, Valencia, CA) from the previously collected two symptomatic and one non-symptomatic scotch bonnet samples. The samples were subjected to reverse-transcription (RT)-PCR assays using SuperScript III One-Step RT-PCR System (Invitrogen, Life Technologies, Grand Island, NY), and using multiplex RT-PCR primer sets (1). The primers were designed to differentiate the CMV subgroup I and II, targeting the partial coat protein gene and the 3′UTR. The RT-PCR assays using the multiplex primers produced an amplicon of 590 bp, with the CMV subgroup I primers. The RT-PCR product was only amplified from the symptomatic leaf samples. The obtained amplicons were gel eluted, and directly sequenced bi-directionally (GenBank Accession Nos. KF805389 and KF805390). BLAST analysis of these sequences showed 97 to 98% nucleotide identities with the CMV isolates in the NCBI database. The isolates collected in Florida exhibited highest identity (98%) with the CMV isolate from tomato (DQ302718). These results revealed the association of CMV subgroup I with symptomatic scotch bonnet leaf samples. Although CMV has been reported from scotch bonnet, this is the first report of its occurrence in Florida. References: (1) S. Chen et al. Acta Biochim Biophys Sin. 43:465, 2011. (2) R. G. Christie and J. R. Edwardson. Plant Dis. 70:273, 1986.


Plant Disease ◽  
2013 ◽  
Vol 97 (8) ◽  
pp. 1124-1124 ◽  
Author(s):  
V. Trkulja ◽  
D. Kovačić ◽  
B. Ćurković ◽  
A. Vučurović, I. Stanković ◽  
A. Bulajić ◽  
...  

During July 2012, field-grown melon plants (Cucumis melo L.) with symptoms of mosaic, chlorotic mottling, and vein banding as well as blistering and leaf malformation were observed in one field in the locality of Kladari (municipality of Doboj, Bosnia and Herzegovina). Disease incidence was estimated at 60%. A total of 20 symptomatic plants were collected and tested with double-antibody sandwich (DAS)-ELISA using commercial polyclonal antisera (Bioreba AG, Reinach, Switzerland) against four the most commonly reported melon viruses: Cucumber mosaic virus (CMV), Watermelon mosaic virus (WMV), Zucchini yellow mosaic virus (ZYMV), and Papaya ringspot virus (PRSV) (1,3). Commercial positive and negative controls were included in each assay. Only CMV was detected serologically in all screened melon samples. Sap from an ELISA-positive sample (162-12) was mechanically inoculated to test plants using 0.01 M phosphate buffer (pH 7.0). The virus caused necrotic local lesions on Chenopodium amaranticolor 5 days after inoculation, while mild to severe mosaic was observed on Nicotiana rustica, N. glutinosa, N. tabacum ‘Samsun,’ Cucurbita pepo ‘Ezra F1,’ and Cucumis melo ‘Ananas’ 10 to 14 days post-inoculation. All five inoculated plants of each experimental host were DAS-ELISA positive for CMV. The presence of CMV in all naturally and mechanically infected plants was further verified by conventional reverse transcription (RT)-PCR. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany) according to the manufacturer's instructions and used as template in RT-PCR. RT-PCR was carried out with the One-Step RT-PCR Kit (Qiagen) using primer pair CMVCPfwd and CMVCPrev (4), amplifying the entire coat protein (CP) gene and part of 3′- and 5′-UTRs of CMV RNA 3. Total RNAs obtained from the Serbian CMV isolate from Cucurbita pepo ‘Olinka’ (GenBank Accession No. HM065510) and healthy melon leaves were used as positive and negative controls, respectively. An amplicon of the correct predicted size (871 bp) was obtained from all naturally and mechanically infected plants as well as from positive control, but not from healthy tissues. The amplified product derived from isolate 162-12 was purified with QIAquick PCR Purification Kit (Qiagen) and sequenced directly using the same primer pair as in RT-PCR (KC559757). Multiple sequence alignment of the 162-12 isolate CP sequence with those available in GenBank, conducted with MEGA5 software, revealed that melon isolate from Bosnia and Herzegovina showed the highest nucleotide identity of 99.7% (100% amino acid identity) with eight CMV isolates originating from various hosts from Serbia (GQ340670), Spain (AJ829770 and 76, AM183119), the United States (U20668, D10538), Australia (U22821), and France (X16386). Despite the fact that CMV is well established in majority of Mediterranean countries and represents an important threat for many agriculture crops, including pepper in Bosnia and Herzegovina (2), to our knowledge, this is the first report of CMV infecting melon in Bosnia and Herzegovina. Melon popularity as well as production value has been rising rapidly and the presence of CMV may have a drastic economic impact on production of this crop in Bosnia and Herzegovina. References: (1) E. E. Grafton-Cardwell et al. Plant Dis. 80:1092, 1996. (2) M. Jacquemond. Adv. Virus Res. 84:439, 2012. (3) M. Luis-Arteaga et al. Plant Dis. 82:979, 1998. (4) K. Milojević et al. Plant Dis. 96:1706, 2012.


Plant Disease ◽  
2013 ◽  
Vol 97 (7) ◽  
pp. 1004-1004 ◽  
Author(s):  
K. Milojević ◽  
I. Stanković ◽  
A. Vučurović ◽  
D. Ristić ◽  
D. Milošević ◽  
...  

Peperomia tuisana C.DC. ex Pittier (family Piperaceae) is an attractive succulent grown as an ornamental. Despite its tropical origins, it can be successfully grown indoors in any climate. In March 2012, three samples of P. tuisana showing virus-like symptoms were collected from a commercial greenhouse in Zemun (District of Belgrade, Serbia) in which estimated disease incidence was 80%. Infected plants showed symptoms including necrotic ringspots and line patterns that enlarged and caused necrosis of leaves. A serious leaf drop led to growth reduction and even death of the plant. Leaves from three symptomatic P. tuisana plants were sampled and analyzed by double-antibody sandwich (DAS)-ELISA using commercial diagnostic kits (Bioreba AG, Reinach, Switzerland) against the most common viral pathogens of ornamentals: Cucumber mosaic virus (CMV), Tomato spotted wilt virus (TSWV), and Impatiens necrotic spot virus (INSV) (1,2). Commercial positive and negative controls were included in each ELISA. Serological analyses showed that all plants were positive for CMV and negative for TSWV and INSV. The ELISA-positive sample (isolate 1-12) was mechanically inoculated onto five plants each of three test species as well as of healthy young P. tuisana using 0.01 M phosphate buffer (pH 7). Chlorotic local lesions on Chenopodium quinoa and severe mosaic and leaf malformations were observed on all inoculated Nicotiana tabacum ‘Samsun’ and N. glutinosa. Also, the virus was successfully mechanically transmitted to P. tuisana that reacted with symptoms identical to those observed on the original host plants. All mechanically inoculated plants were positive for CMV in DAS-ELISA. For further confirmation of CMV infection, reverse transcription (RT)-PCR was performed on extracts made from symptomatic P. tuisana, N. tabacum ‘Samsun,’ and N. glutinosa leaf materials. Total RNAs were extracted with the RNeasy Plant Mini Kit (Qiagen, Hilden, Germany) and RT-PCR was carried out using One-Step RT-PCR Kit (Qiagen). A CMV-specific primer pair, CMVCPfwd and CMVCPrev (3), which amplifies an 871-bp fragment of the entire coat protein (CP) gene and part of 3′- and 5′-UTRs, were used for both amplification and sequencing. Total RNAs obtained from the Serbian CMV isolate (HM065510) and healthy P. tuisana were used as positive and negative controls, respectively. A product of the correct predicted size was obtained in all naturally and mechanically infected plants, as well as positive control. No amplicon was recorded in the healthy control. The amplified product derived from isolate 1-12 was purified (QIAquick PCR Purification Kit, Qiagen), directly sequenced in both directions, deposited in GenBank (KC505441), and analyzed by MEGA5 software (4). Sequence comparison of the complete CP gene (657 nt) revealed that the Serbian isolate 1-12 shared the highest nucleotide identity of 99.1% (99.5% amino acid identity) with the Japanese isolate (AB006813). To our knowledge, this is the first report on the occurrence of CMV in P. tuisana in Serbia. This is also an important discovery since P. tuisana is commonly grown together with other ornamental hosts of CMV, and thus could represent a serious threat for future expansion of CMV in the greenhouse floriculture industry in Serbia. References: (1) M. L. Daughtrey et al. Plant Dis. 81:1220, 1997. (2) S. Flasinski et al. Plant Dis. 79:843, 1995. (3) K. Milojevic et al. Plant Dis. 96:1706, 2012. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.


Plant Disease ◽  
2014 ◽  
Vol 98 (11) ◽  
pp. 1589-1589
Author(s):  
J. Du ◽  
C. M. Zhang ◽  
Y. B. Niu

Agastache rugosa (family Lamiaceae) is one of the most common herbs of traditional Chinese medicine in China, and the species increasingly gains popularity on the international market. In June 2012, typical mosaic symptoms were observed on many A. rugosa plants in a field in Shanxi Province. The incidence of this disease reached more than 60% in a 2.6-ha field. Seven symptomatic plants were tested by DAS-ELISA using monoclonal antibodies specific for Tobacco mosaic virus (TMV), Cucumber mosaic virus (CMV), and Tomato mosaic virus (ToMV); all antisera used in DAS-ELISA were generated and validated in our laboratory. CMV was found in all seven samples tested, but not TMV and ToMV. Double-stranded RNAs (dsRNA) extracted from infected leaves were used as templates in the subsequent two-step RT-PCR reaction (1). In order to further confirm the presence of CMV, a pair of specific primers (forward: 5′-ACGTCGACCATGGACAAATC-3′, and reverse: 5′-TACCCGGGTCAGACTGGTAGCACC-3′) based on the coat protein gene sequence of CMV were used to amplify PCR products of the expected size (657 bp) from ELISA-positive samples (2). These PCR products were cloned into pUCm-T Vector (Sangon Biotech, Shanghai) and sequenced. Five independent clones have been sequenced to obtain the consensus sequence. This consensus sequence (GenBank Accession No. JQ403529) was compared with other CMV sequences available in GenBank using DNAMAN. The partial CMV coat protein sequence showed the highest 97.9% nucleotide identity with a subgroup IB CMV isolate from China (DQ459481). To our knowledge, this is the first report of the natural occurrence of CMV on A. rugosa. References: (1) M. Krajacić et al. J. Chromatogr. A. 1144:111, 2007. (2) F. Li et al. J. Zhejiang Univ. 26:261, 2000.


Plant Disease ◽  
2013 ◽  
Vol 97 (7) ◽  
pp. 1002-1002 ◽  
Author(s):  
K. Vrandečić ◽  
D. Jurković ◽  
J. Ćosić ◽  
I. Stanković ◽  
A. Vučurović ◽  
...  

Lavandin (Lavandula × intermedia Emeric ex Loiseleur) is cultivated on a large scale in some South European countries for the extraction of essential oils or as an ornamental plant for gardens and landscapes. In May of 2012, virus-like symptoms including bright yellow calico mosaic, leaf distortion, and growth reduction were observed on 15% of lavandin plants in a commercial nursery in Banovo Brdo locality, Baranja County, Republic of Croatia. Leaves from 15 symptomatic lavandin plants were collected and examined by double-antibody sandwich (DAS)-ELISA using commercial antisera (Bioreba AG, Reinach, Switzerland) against two viruses known to infect Lavandula spp.: Alfalfa mosaic virus (AMV) and Cucumber mosaic virus (CMV) (2,3). Commercial positive and negative controls and extracts from healthy lavandin leaves were included in each ELISA. Only AMV was detected serologically in all 15 tested samples. Five plants each of Chenopodium quinoa, C. amaranticolor, and Nicotiana benthamiana were mechanically inoculated with sap from an ELISA-positive sample (70-12) using 0.01 M phosphate buffer (pH 7). Local chlorotic spots accompanied by systemic mosaic on both Chenopodium species and bright yellow mosaic on N. benthamiana were observed 6 and 12 days post-inoculation, respectively. Test plants were assayed by DAS-ELISA and all inoculated plants of each species tested positive for AMV. The presence of AMV in all symptomatic lavandin plants was further confirmed by reverse transcription (RT)-PCR assay. Total nucleic acid was extracted using RNeasy Plant Mini Kit (Qiagen, Hilden, Germany). RT-PCR was performed with the One-Step RT-PCR Kit (Qiagen) using AMV specific primer pair CP AMV1 (5′-TCCATCATGAGTTCTTCAC-3′) and CP AMV2 (5′-AGGACTTCATACCTTGACC-3′) (1). Total RNAs obtained from the Serbian AMV isolate from alfalfa (GenBank Accession No. FJ527748) and healthy L. × intermedia plant served as the positive and negative control, respectively. The 751-bp amplicons, covering the partial coat protein (CP) gene and 3′-UTR, were obtained from all 15 samples that were serologically positive to AMV as well as from positive control. No amplification product was observed when extract from healthy L. × intermedia plant was used as template in the RT-PCR assay. The RT-PCR product derived from isolate 70-12 was directly sequenced in both directions using the same primer pair as in RT-PCR and deposited in GenBank (JX996119). Multiple sequence alignment of the CP open reading frame was performed by MEGA5 software (4) and revealed that the isolate 70-12 showed the highest nucleotide identity of 99.4% (99.5% amino acid identity) with Serbian AMV isolate from tobacco (FJ527749). To our knowledge, this is the first report of AMV on L. × intermedia in Croatia. Because lavandin is an aromatic plant traditionally and widely grown in Croatia, the presence of AMV could be a limiting factor for its successful production. References: (1) M. M. Finetti-Sialer et al. J. Plant Pathol. 79:115, 1997. (2) T. Kobylko et al. Plant Dis. 92:978, 2008. (3) L. Martínez-Priego et al. Plant Dis. 88:908, 2004. (4) K. Tamura et al. Mol. Biol. Evol. 28:2731, 2011.


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