• Research in Plant Disease
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• v.7 no.3
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• pp.170-174
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• 2001

Gelatin particle agglutination test (GPAT) was optimized for detection of Tobamovirus and contamination of the virus in commercial pepper seeds was evaluated. The optimum concentration of ${\gamma}$-globulin G, specific to tobacco mosaic virus pepper strain, was 100 ug/ml. The sensitivity of GPAT for the detection of Tobamovirus in pepper seeds was as high as enzyme-linked immunosorbent and dot immunoblotting assays. Optimum dilution ranges of the seed extract for GPAT was 5-25 folds. Using the optimized GPAT with above conditions, the rate of Tobamovirus contamination in seeds was turned out to be average of 79.1%.

• Research in Plant Disease
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• v.7 no.3
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• pp.164-169
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• 2001

Two Tobamoviruses showing different local lesion types on Nicotiana glutinosa was isolated from commercial pepper seeds. These viruses were designated Tobamovirus-6 (T-6) and Tobamovirus-19 (T-19). The biological and serological assays revealed that T-6 and T-19 were closely related to Pepper mild mottle virus (PMMoV) and Tomato mosaic virus (ToMV), respectively, The isolates also had low similarity in the array of viral coat protein gene sequences, of which T-19 was most identical to known strains of ToMV, while T-6 was closely related to PMMoV.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.530-534
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• 2001

A total of 23 isolates were obtained from seeds of 30 pepper cultivars by single lesion isolation on Nicotiana glutinosa. The isolates were tested for pathotype determination using standard pepper differentials. Two pathotypes of Tobamoviruses, namely P0 and P1.2 were detected from the pepper seeds, of which pathotype P1.2 was predominant. Pathotypes P1 and P1.2.3 were unable to detect in this study. All pepper cultivars except one showed resistance to two pathotypes, P0 and P1, but not to pathotype P1.2. These results could be useful for breeding Tobamovirus-resistant pepper and producing virus-free seed stock.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.114.1-114
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• 2003

A new isolate of rod-shaped virus was identified from grafted cactus, Gymnocalycium mihanovichii grafted onto Hylocereus trigonus, in Korea. The virus proved to be a new Tobamovirus and called previously as Tobamovirus-Ca for which we suggest the name Cactus mild mottle virus(CMMoV), because it produced systemic mild mosaic symptoms on its original host. CMMoV is distantly related to known species of the genus Tobamovirus on the basis of host range, serological and sequence analyses. Western blot analysis showed that CMMoV is serologically unrelated to Summons' Opuntia virus which is the only known species of the genus found in cactus plants. The 3'-terminal 2,910 nucleotides have been sequenced for the virus. The coat protein (CP) and movement protein (MP) genes encode 161 and 306 amino acids residues, respectively. The nucleotide and amino acid sequences of the CP were 39.6 ％ to 49.2 ％ and 26.4 ％ to 40.3 ％ identical to other tobamoviruses, respectively. The MP and 3' noncoding region shared 16.3 ％ to 23.3 ％ and 44.6 ％ to 63.4 ％ identities, respectively, with the members of the genus. Phylogenetic tree analysis of the CP gene revealed that CMMoV clusters with members of subgroup I of Tobamovirus. CMMoV particles contained genomic RNA along with two subgenomic RNAs, and this characteristics is common in the members of the subgroup II. This is the first information of sequence and comparative analysis of a Tobamovirus that infects cactus.

• Research in Plant Disease
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• v.17 no.2
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• pp.191-195
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• 2011

This experiment was attempted to investigate a cause of the scion death in green pepper grafting system. A tobamovirus particle examined in the rootstock of the sample but not in the scion showing necrosis. The virus isolated from the rootstock was identified as Pepper mild mottle virus (PMMoV), pepper tobamovirus pathotype P1.2. (PMMoV-2), by nucleotide sequence analysis and host plant reaction. The virus isolate infected systematically in 6 commercial rootstock varieties using for green pepper grafting seedling production. Green pepper varieties 'Long green mart' and 'Daechan' represented resistance to the virus showing local lesions only on the inoculated leaves and 'Manitda' was systematically infected. In the experiment with grafting 'Long green mart' or 'Daechan' onto the those rootstocks, the upper leaves of the scions first showed vein necrosis and wilt symptoms 7 days after inoculation with PMMoV-2 on the cotyledon of the rootstock, following to the scion stem necrosis and then only the scion death. The virus was detected in the rootstock but not in the scion. However, 'Manitda' of susceptible variety in the grafting system showed mottle symptom on the leaves of the scion but not necrosis on the plant. PMMoV-3 isolate, pepper tobamovirus pathotype P1.2.3, did not cause the scion death in the grafting system. All of the varieties were susceptible to PMMoV-3. These results suggest that the scion death is caused by infecting with pepper tobamovirus pathotype P1.2. in the green pepper grafting system combined with the susceptible rootstock and the resistance scion to the virus pathotype.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.286-293
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• 2012

The resistance to Tobamovirus in Capsicum spp. has been known to be controlled by five different alleles ($L^0$, $L^1$, $L^2$, $L^3$, and $L^4$) of L locus on the telomere of long arm of pepper chromosome 11. To develop a set of molecular markers differentiating all the alleles of L locus, we used five pepper differential hosts including Capsicum annuum Early California Wonder (ECW, $L^0L^0$), C. annuum Tisana ($L^1L^1$), C. annuum Criollo de Morelos 334 (CM334, $L^2L^2$), Capsicum chinense PI 159236 ($L^3L^3$), and Capsicum chacoense PI 260429 ($L^4L^4$). Developing a series of CAPS or SCAR markers specifically linked to the alleles was allowed by the sequence comparison of PCR amplicons of the $L^3$-linked markers (189D23M, A339, and 253A1R) and BAC sequences (FJ597539 and FJ597541) in the pepper differentials. Genotypes deduced by these markers in 48 out of 53 $F_1$ hybrids of commercial pepper varieties were consistent with their phenotypes by bioassay using Tobamovirus pathotypes ($P_0$, $P_1$, and $P_{1,2$). Consequently, these markers can be useful to differentiate L alleles and for breeding Tobamovirus resistance in pepper with marker-assisted selection.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.211-215
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• 2000

Symptoms on 4 varieties of watermelons inoculated with watermelon mosaic potyvirus II isolated from watermelon (WMV-W) were severe mosaic and leaf malformation while those inoculated with cucumber green mottle mosaic tobamovirus from watermelon (CGMMV-W) were mild mosaic and chlorotic spots. Inoculation of the mixture of WMV-W and CGMMV-W produced extremely severe mosaic along with necrotic spots and general necrosis. Doubly infected plants were also stunted. Cells infected with WMV-W or CGMMV-W alone exhibited the intrinsically ultra-structural properties of each virus infection. WMV-W induced potyvirus-characteristic cylindrical inclusions in the cytosol. Virus particles were orderly aligned along the tonoplasts. CGMMV-W induced tobamovirus-characteristic stacked crystalline arrays of virus particles in the cytosol. Cells infected doubly with WMV-W and CGMMV-W contained striking cytopathic effects that were not present in single infection of each virus. The unique ring structure, nonagon, was that a single potyvirus particle was surrounded by 9 CGMMV-W tobamovirus particles.

• Research in Plant Disease
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• v.10 no.3
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• pp.194-197
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• 2004

Incidence of tobamovirus diseases was 100％ at late growth stage of green pepper on hydroponic systems in plastic house. Infection frequency of the diseases showed 34％ of Pepper mild mottle virus (PMMoV), 41.5％ of Tobacco mild green mottle virus (TMGMV), and 24.5％ of the co-infected viruses. The two viruses specifically reacted in DAS-ELISA prepared with each polyclonal antibody. A total of 77 pure tobamovirus isolates obtained from the crops was tested for pathotype determination. The isolation frequency of tobamovirus pathotype $P_{0}$ and $P_{1,2}$ was 61 ％ and 39％, respectively. All TMGMV isolates belonged to the pathotype $P_{0}$. In restriction enzyme analysis of the cDNAs synthesized with coat protein gene of PMMoV pathotype $P_{0}$ and $P_{1,2}$, the former had two TaqI sites but the later had one.one.

• The Plant Pathology Journal
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• v.17 no.4
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• pp.201-204
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• 2001

Ultrastructural observation was conducted for the cells of oriental cabbage, Brassica campestris ssp. pekinensis 'Chungawang', inoculated simultaneously with Turnip mosaic virus (TuMV-ACT2-4vq) and Ribgrass mosaic virus (RMV-Ca1dn2) which were known as major destructive viruses of oriental cabbage in Korea. In cells infected with RMV alone, the virus particles were located as bundle or scattering in cytosols and vacuoles, which were typical ultrastructures of tobamovirus. Vessels of xylem were compacted with RMV particles. The cells infected only with TuMV had the cluster of virus particles scarcely and the typical potyvirus inclusions of scrolls, pinwheels, tubes and laminated aggregates in cytosols. The TuMV particles were jammed lineally between tonoplasts. In double infection, the two unrelated viruses of TuMV-ACT2-4vq and RMV-CA1dn2 were located together in a cell, and typical properties of each virus were also observed. The potyvirus inclusions and the tobamovirus particles were mixed entirely in cytoplasm. The virus particles of RMV wre presented strikingly near and in the center of potyvirus inclusions. In vascular cells, the tobamovirus particles were located abundantly than those in single infection. The potyvirus inclusions were embedded in the cluster of RMV particles in phloem parenchyma cells and the vascular elements were degenerated severely.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.216-221
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• 2000

Mixed infection of watermelon mosaic potyvirus II isolated from pumpkin (WMV-P) and cucumber green mottle mosaic tobamovirus from watermelon (CGMMV-W) caused extremely severe symptoms such as progressive silting and death of watermelon plants. Single infections of either WMV-P or CGMMV-W on the same hosts produced only vein clearing and/or mosaic on the upper leaves. In cells infected with WMV-P, potyvirus-characteristic inclusions of pinwheels, scrolls and cylindrical inclusions were present in the cytosol. Parallel arrays of virus particles in the tonoplast were also common. In cells infected with CGMMV-W, virus particles occurred as stacked-bands of scattered randomly in the cytosol and vacuoles in all type cells. Many cells also contained vesiculated mitochondria with fibril-containing vesicles. Cells infected mixedly with WMV-P and CGMMV-W contained structural features that were not observed in cells infected singly with the two viruses. A particle of WMV-P potyvirus was surrounded by evenly spaced nine particles of CGMMV-W tobamovirus, which made a unique nonagon ring. The angled layers having $60^{\circ}$-$135^{\circ}$ were alternating layer, herringbone, crosshatching and ladder figures.