Carnation Viruses Research Articles

Genome Sequence of a New Carnation Small Viroid-Like RNA, CarSV-1.

Here, we report the genome sequence of a new circular viroid-like RNA (CarSV-1) derived from Dianthus caryophyllus (carnation) leaves. The CarSV-1 genome has notable sequence similarity (62%) to the well-studied CarSV viroid-like RNA and comprises the complete hammerhead consensus sequences involved in self-cleavage. CarSV-1 co-occurs with carnation viruses, such as CarMV.

Plant tissue distribution and chemical inactivation of six carnation viruses

Carnation mottle virus (CarMV), Carnation etched ring virus (CERV), Carnation vein mottle virus (CVMV), Carnation ringspot virus (CRSV), Carnation Italian ringspot virus (CIRV) and Carnation latent virus (CLV) are the most important viruses affecting carnation crops. All except CERV are RNA viruses. Viral RNA or DNA accumulation on root, stem, leaf, sepal, petal, stamen, pistil and ovary tissues of infected carnation or Saponaria vaccaria plants was analysed by non-isotopic molecular hybridisation. High-titres of CarMV, CRSV, CIRV, and CLV accumulated in all plant tissues whereas CERV and CVMV were irregularly distributed over the plant. High-titres of all viruses accumulated in leaf, petal, stamen, pistil, and ovary tissues, so leaves or petals are a good tissue for routine diagnosis. Six chemicals were evaluated for inactivation of all carnation viruses in infected extracts. Commercial bleach at 7% (v/v) or NaOH at 0.5% (w/v) was found to inactivate all viruses after 60 s treatment in a systemic S. vaccaria bioassay.

Distribution of carnation viruses in the shoot tip: Exclusion from the shoot apical meristem

Cell biological tools were used to localize the genomic RNAs/DNA and/or the coat protein (CP) of Carnation mottle, Carnation vein mottle, Carnation latent, and Carnation etched ring viruses in the carnation shoot tip to know whether any of them was capable of infecting the shoot apical meristem. Our results showed that all the viruses studied were excluded not only in single-infected but also in double-infected plants. Despite that, these viruses showed a different infection pattern inside the shoot tip, with different cell types being their main targets. For the mixed infection studied here, our results showed the existence of a spatial separation pattern within the carnation shoot tip which strongly suggests an exclusion phenomenon.

Occurrence of a Severe Strain of Lisianthus necrosis virus in Imported Carnation Seedlings in Taiwan

In the 1995 to 1996 season, severe viral disease symptoms were observed on carnations (Dianthus caryophyllus [hybrid Kooij Echo kgr]) propagated from imported seedlings on farms in central Taiwan. Disease symptoms began on upper leaves as numerous yellow spots that enlarged and fused into large chlorotic patches and expanded to cover entire leaves, which eventually became necrotic. Electron microscopy of crude extracts, purified preparations, and ultrathin sections of diseased tissues revealed the presence of isometric particles ≈32 to 33 nm in diameter. Earlier, in the 1994 to 1995 season, a strain of Lisianthus necrosis virus (LNV-L) was identified in lisianthus (Eustoma russellianum (Don.) Griseb) in a nearby nursery propagating seedlings (1). Both the lisianthus and carnations were imported from Europe. Chlorotic leaves from carnations reacted strongly with antiserum prepared against LNV-L in tissue blot immunoassay. Extracts of diseased leaves also reacted positively to LNV-L antiserum in both immunodiffusion and doubleantibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) tests. Mouse monoclonal antibodies prepared against LNV-L reacted positively based on indirect ELISA with extracts of chlorotic carnation leaves. The capsid protein of the carnation virus (LNV-D) was ≈38 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, similar to the LNV-L coat protein (1), and reacted with LNV-L antiserum in western blot analysis. LNV-D differs biologically from LNV-Japan and LNV-L isolates previously reported in Japan and Taiwan, respectively (1,2). In experiments, LNV-D has induced systemic infection in many hosts that are either nonhosts or local-lesion hosts for LNV-Japan or LNV-L. D. caryophyllus L. and D. chinensis L. are susceptible to systemic invasion by LNV-D but are nonhosts for LNV-Japan and LNV-L. D. barbatus L. is a systemic host for LNV-D but a nonhost for LNV-L and has not been tested as a host for LNV-Japan. Chenopodium amaranticolor Coste & Reyn. and C. quinoa Willd. are systemic hosts for LNV-D but are local-lesion hosts for both LNV-Japan and LNV-L. Capsicum annuum L. is a systemic host for LNV-D and LNV-L but is not susceptible to LNV-Japan. Lycopersicon esculentum Mill. is a systemic host for LNV-D, a local-lesion host for LNV-L, and a nonhost for LNV-Japan. All three isolates systemically infect E. russellianum, the only systemic host for all three isolates tested. The first reports of LNV in Japan and later in Taiwan were in lisianthus. To our knowledge, this is the first report of the natural occurrence of LNV in imported carnation seedlings in Taiwan. LNV infection in Taiwan was only noticed once in lisianthus (1994 to 1995 season) and once in carnation (1995 to 1996 season) in farms propagating imported seedlings. LNV is transmitted by Olpidium sp. (2). Olpidium-like structures were not observed in Taiwan in rootlets of diseased carnation and lisianthus nor were they isolated from soil around diseased plants. Surveys of LNV in the nurseries and nearby areas in subsequent years have not found a new case of infection. We believe that LNV disease is not endemic in Taiwan and that its occurrence in lisianthus and carnation are one-time incidents caused by the importation of infected seedlings or contaminated culture matrices associated with the seedlings.

Simultaneous detection of five carnation viruses by non-isotopic molecular hybridization

Several viruses, which in some cases can cause severe losses, affect carnation plants. These viruses include carnation mottle virus, carnation etched ring virus (CERV), carnation vein mottle virus, carnation ringspot virus, carnation Italian ringspot virus and carnation latent virus. A non-isotopic molecular hybridization was developed for the detection of these viruses in host plants and the sensitivity of the technique has been compared with enzyme-linked immunosorbent assay and bioassay methods. A procedure was developed to test simultaneously for the five RNA viruses (except CERV). The conditions established for this simultaneous detection did not include the DNA virus CERV due to the necessity of incorporating an additional step of RNase A treatment in the procedure to eliminate background signals. The sensitivity limits obtained for each virus using this multiple detection assay were identical to those obtained with the individual assays. The relative benefits of using this detection procedure for routine diagnosis of carnation viruses are discussed.

Isolation of Carnation Ringspot Virus from a Canal Near a Sewage Plant: cDNA Hybridization Analysis, Serology and Cytopathology

AbstractA small water sample of only 60 ml from the Oker Aue canal near Braunschweig was ultracentrifuged. The resuspended pellet was rubbed on Chenopodium quinoa leaves which responded with the formation of almost 200 local lesions. The virus causing these lesions was identified as carnation ringspot virus (CarRSV) by means of dot blot hybridization using random‐primed cDNAs to the viral nucleic acids and by means of serology. Northern blot analysis revealed that the two RNA species of the virus which consisted of c. 3.7 and 1.5 Kb, respectively, have little or no base sequence homology. In immunoelectrophoresis at pH 7.0 the virus migrated towards the cathode. The isometric particles were 33 nm in diameter, round to slightly angular in outline, and showed a distinct granular or knobly surface structure. Virus particles occurred in the cytoplasm, nuclei, and vacuoles of infected cells which in addition contained amorphous granules in the cytoplasm and/or proliferated endoplasmic reticulum. Heavily, affected cells were necrotized and contained large virus particle aggregates which sometimes were crystallized.CarRSV is the third carnation virus, after carnation mottle and carnation Italian ringspot viruses, which was identified in a natural water.

An Addition to the Obituary of John Daniel Gilpatrick

includes, of course, some publications on the so-called 'b' proteins While John was at St. Catharines, I was privileged to be closely that are associated with this phenomenon, the associated with him. We worked on a number of plant virus significance and function of which are still a source of puzzlement problems, most of which related to virus inhibitors and and debate. Because this is increasingly active area of research, it mechanisms of interference with virus infection. We discovered an would be unfortunate if John D. Gilpatrick's role in its discovery unusual type of protection in Dianthus barbatus inoculated with a was not recognized in a review of his scientific achievements. carnation virus: after the production of viral local lesions, the uninoculated leaves on the test plant were resistant or immune to

Investigations of carnation viruses

SUMMARYCarnation vein mottle virus (CarVMV) is rare in glasshouse carnations in Britain, although locally common in Dianthus barbatus in private gardens. In Sim carnations free from other viruses, CarVMV caused slight diffuse chlorotic mottling in the younger leaves, decreased flower yield by c. 22%, and caused flower breaking in cvs William Sim and Dusty. In non‐Sim cultivars Pink Shibiuya, Orchid Beauty and Vesta, leaf symptoms and flower breaking were more pronounced. In mixed infections with carnation mottle virus, symptoms were much more severe.CarVMV was not eliminated from carnation or D. barbatus plants grown for 4 wk at 37oC, and only rarely from cuttings then taken from them, but it was readily eliminated by meristem‐tip culture. Myzus persicae adults or nymphs acquired and transmitted the virus within a total time of 4 min, and remained infective for 30–60 min if feeding, or for 75 min if starved. The carnation aphid, M. persicae f. dianthi, transmitted the virus much less efficiently. The virus was not transmitted by dodder (Cuscuta campestris), or through seed of D. barbatus or Chenopodium quinoa. The maximum infective dilution in sap of D. barbatus, carnation and C. quinoa ranged from 10‐2 to 10‐5. The virus withstood 10 min at 60 but not 65oC, up to 9 days at c. 18oC or 3–4 wk at c. 2oC.CarVMV infected twenty‐two of 107 plant species in six of thirty‐seven families; suscepts were confined to the Chenopodiaceae, Caryophyllaceae and closely allied families. C. quinoa was the best local lesion assay host. Seedling clones of D. barbatus, selected as resistant to carnation mottle virus, proved the best indicator and propagation species.Up to 50 mg virus/kg tissue were obtained by butanol clarification followed by differential and density gradient centrifugation. The preparations contained a single sedimenting component, s20w= 144S, and had flexuous filamentous particles, c. 790 times 12 run; the particles contained a single polypeptide, mol. wt 34800, and 5% of a single‐stranded ribonucleic acid (RNA) with nucleotide base ratios of G21: A25: C25: U29.Serologically CarVMV was related distantly to turnip mosaic (cabbage black ring strain), pea mosaic, watermelon mosaic (Strain 2) and bean yellow mosaic viruses, more closely to pepper veinal mottle virus, but unrelated to twelve other potyviruses.CarVMV is not at present a danger to carnation crops in Britain, but the recent trend of sending carnation plants to overwinter outdoors in warmer countries involves potential risks of more rapid spread by effective vector races of M. persicae.

Carnation Viruses in Australia.

Carnation Viruses in Australia.

Haemagglutination with Plant and Insect Viruses

SUMMARY: The passive haemagglutination test and the sensitivity of the haemagglutination inhibition test were investigated by using two plant viruses (tobacco mosaic virus and latent carnation virus) and an insect virus, tipula iridescent virus. The minimum quantities detectable by these methods were of the order of 0.26 to 0.015 μg. There was no direct agglutination by tobacco mosaic virus or tipula iridescent virus of erythrocytes from a variety of animals.

Investigation of carnation viruses

SUMMARYCarnation ringspot virus (CRSV) was isolated from twenty‐three carnation cultivars, was readily transmitted by grafting and sap‐rubbing inoculation, and was spread among carnations by handling. CRSV was cultured in Nicotiana clevelandii or carnation and assayed in Chenopodium amaranticolor; Gomphrena globosa was the best diagnostic indicator plant.CRSV was not transmitted by Myzus persicae or through seed of Dianthus barbatus. The virus infected sixty‐two out of ninety‐six plant species tested, but carnation is the only plant likely to be a virus source for commercial stocks. The concentration of CRSV decreased greatly in the terminal 1–2 mm. of the carnation shoot apex and, unlike carnation mottle, CRSV was not detected in the meristem dome; it was, however, present in some first leaf primordia. Clones free from the virus were obtained by aseptic culture of excised meristem‐tips, but more easily by growing infected carnations at 38–40d̀ C. for 4 weeks, followed by striking small cuttings or culturing meristem‐tips. N. clevelandii sap was infective after dilution to 1/100,000, heating for 10 min. to 85d̀ C. but not 90d̀ C., and storage for 16 days at 20d̀ C. or 3 months at 0d̀ C. Purified and concentrated preparations of CRSV from carnation, D. barbatus or N. clevelandii were highly infective, contained polyhedral particles about 29 mμ diameter, were antigenic, and produced a specific light‐scattering zone in density‐gradient centrifugation. The S20, w at infinite dilution was 140. CRSV shares many in vitro properties with eleven other viruses having similar particle shape, but it was not serologically related to any of them.

Carnation viruses in Japan

Carnation viruses in Japan

Investigation of carnation viruses

SUMMARYCarnation mottle virus (CarMV) was present in every plant tested of over forty‐four varieties from commercial carnation stocks. Inhibitors of infection in carnation sap prevent transmission to many species, but not to Chenopodium amaranticolor, which proved the best indicator and assay host. CarMV infected thirty‐three of 113 plant species inoculated, but only Dianthus spp. are likely to be affected in practice. Healthy carnations were infected when handled after diseased ones. CarMV was not transmitted by Myzus persicae, through carnation seed, or through dodder (Cuscuta campestris).The type strain occurred in all ‘Sim’ carnations tested; another strain, designated ‘PSR’, occurred in vars. Pink Shibiuya and Orchid Beauty. The two strains were distinguished by the symptoms caused in Chenopodium amaranticolor and other plants. The type strain protected against the PSR strain in Atriplex hortensis. An ‘attenuated’ form of the virus, which multiplied much more slowly than the typical form, withstood adverse conditions better.Although the virus concentration decreased in the terminal 1–2 mm. of the carnation shoot apex, CarMV was always detected in the meristem dome. Nevertheless, some virus‐free clones were obtained by aseptic culture of excised tips. CarMV was not eliminated by growing plants at 38°C., although its concentration in the apical tissues was diminished.Sap was infective after dilution to I/200,000, heating (10 min.) to 85°C. (but not 90°C.), storage for up to 81 days at 18°C., or over 3 years at o°C. Purified and concentrated preparations of CarMV were readily obtained from carnation by several methods: they contained ‘spherical’ particles about 28 mμ diameter, were antigenic, and produced a specific light‐scattering virus zone in density‐gradient centrifugation. The S20,w at infinite dilution was 122.Although CarMV shares many in vitro properties with eleven other viruses having similar particle shape, it is not serologically related to any of them and differs in other respects.Control of the virus depends on the production and distribution of virus‐free clones of carnation.

REMOVAL OF HOST ANTIGENS FROM PLANT VIRUS PREPARATIONS BY ION EXCHANGE CHROMATOGRAPHY

The separation of a carnation virus from smaller cowpea-host antigens was achieved by column chromatography on a strongly basic ion-exchange resin. The separation was demonstrated by infectivity and serological tests, analytical ultracentrifugation, and ultraviolet spectrophotometry. The method is proposed for the removal of similar host components from preparations of other spherical plant viruses.

STUDIES ON THE METABOLISM OF LEAVES WITH LOCALIZED VIRUS INFECTIONS: I. OXYGEN UPTAKE

Infection of Nicotiana glutinosa with tobacco mosaic virus, of Dianthus barbatus with a carnation virus, of Gomphrena globosa with potato virus X, and of N. tabacum with two strains of turnip mosaic virus produced local lesions and significantly increased O2 uptake to an extent dependent upon the stage of infection. Increased respiration in N. glutinosa, as measured by O2 uptake, was detected 7–10 hours before lesions appeared. When infected plants were maintained at 32 °C, the rise in respiration occurred 8–15 hours before the appearance of lesions, indicating an increase or prolongation of virus multiplication. Local lesion infection of other hosts, though differing in detail, had essentially the same effect. Non-virus injury, including artificially produced necrotic local lesions, did not induce a similar increase in respiration. When necrotic areas were excised from infected disks the remaining portions still respired at a greater rate than healthy controls. Increased respiration appeared to be correlated with virus activity other than the necrotic process.

Serological relations between potato paracrinkle virus, potato virus S and carnation latent virus.

SUMMARY: Evidence is given that potato paracrinkle virus, potato virus S and carnation latent virus are serologically related and should be considered as related virus strains, although they differ considerably in their host range and pathogenicity, and only carnation latent virus is transmissible by aphids. It is suggested that the three have evolved from a common aphid-transmitted ancestor. In addition to the antigens which the three have in common, each has many specific ones, and the two strains from potato are more closely related to one another than to the carnation virus. No plant of the potato variety King Edward was found free from paracrinkle virus, and no Arran Victory plant free from virus S. Minor variants of both paracrinkle virus and of virus S were detected; it is suggested that the variations in severity of symptoms developed when Arran Victory plants are grafted with King Edward scions reflect the various degrees to which different isolates interfere with each other’s multiplication. Most isolates of virus S interfere only slightly with the multiplication of paracrinkle virus.