Sugarcane Mosaic Virus Strain Research Articles

Outbreak of Sugarcane Mosaic in Commercial Sugarcane Cultivar CP 72-2086, in Florida.

In May 1996, an outbreak of sugarcane mosaic virus (SCMV) was detected in Florida affecting a major commercial sugarcane (Saccharum spp. hybrid) cultivar, CP 72-2086. Identification of SCMV was confirmed by enzyme-linked immunosorbent assay (ELISA) with SCMV antiserum (ATCC no. PVAS 115), and by reverse transcription(RT)-PCR (1,2). The strain of SCMV was identified as E with an RT-PCR-based restriction fragment length polymorphism analysis (1). Although SCMV strain E has been detected in Florida for many decades, it had been confined primarily to S. officinarum clones, to occasional susceptible sugarcane clones in breeding programs, and to various grasses throughout the sugarcane production area. CP 72-2086 plus seven other sugarcane cultivars and 10 sorghum cultivars reacted similarly to inoculation with the isolate of SCMV found recently on CP 72-2086 and an isolate of SCMV collected in 1986. CP 72-2086 was released in 1982 and currently is the second most widely grown cultivar, constituting 18.0% of the commercial sugarcane area in Florida. At the epicenter of infection, located 11 km southeast of Canal Point, over 50% of CP 72-2086 plants had SCMV symptoms. The incidence of mosaic decreased rapidly away from the epicenter. No SCMV was observed in the western area of the sugarcane production area, west of South Bay, FL.

ENZYME LINKED IMMUNOSORBENT ASSAY (ELISA) FOR THE DETECTION OF SUGARCANE MOSAIC VIRUS

Sugarcane mosaic virus (SCMV) a member of Potyvirus group is an important disease of sugarcane. Currently, the virus is identified based on the foliar symptoms exhibitd by the virus on differential hosts. An indirect-ELISA was standardised to detect the presence of virus in the host very precisely. Antigen dilution of 1:500, antiserum dilution of 1:1000 and enzyme conjugate dilution of 1:8000 were found optimum for the detection of the suspected virus in the host. In highly susceptible varieties, SCMV presence was detected even at a dilution of 1 x 105 by ELISA test. Polyclonal antisera developed against SCMV strain-N was found suitable to detect suspected samples of other SCMV strains also. This technique will have greater applications in the routine quaratine work of this Institute.

Sequence Analysis of the Genomic RNA 3′‐terminal Region of a Potyvirus from Brachiaria spp. Related to Gulneagrass Mosaic Virus

AbstractThe 3'terminal region of the genomic RNA of a potyvirus isolated from Brachiaria spp. which is related to guinea grass mosaic virus (GGMV), was compared to that of members of the sugarcane mosaic subgroup of poty viruses. Reverse transcription‐polymerase chain reaction (RT‐PCR) of total nucleic acid extracted from infected B. brizantha resulted in the amplification of a DNA product of c. 0.9 kb. This product was cloned and sequenced, it has an open reading frame of 149 amino acid residues, and a 3'untranslated region (UTR) of 474 nucleotides. Optimal alignments of the 3'UTRs of the Brachiaria potyvirus and members of the sugarcane mosaic subgroup of potyviruses showed that it has nucleotide sequence similarities of c. 42. 46, 46, and 46% to maize dwarf mosaic virus strain A, sugarcane mosaic virus strains SC and MDB, and sorghum mosaic virus strain SCH, respectively. It had higher nucleotide sequence similarities of c. 88, 89, and 92% with Johnsongrass mosaic virus (JGMV) strains MDO, MDKSl and JG, respectively. Analyses of the deduced amino acid sequence of the Brachiaria potyvirus coat protein fragment revealed a 97.3% similarity to the JG strain of JGMV to which it is scrologically related. We propose that the Brachiaria potyvirus now be considered a strain of JGMV (designated JGMV‐Brac).

Incidence and severity of viral disease symptoms on eastern gamagrass within monoculture and polycultures

Sugarcane mosaic virus strain maize dwarf mosaic virus B (SCMV-MDMV-B) and maize dwarf mosaic virus (MDMV) are aphid-vectored potyviruses that infect eastern gamagrass ( Tripsacum dactyloides (L.) L.), a perennial grain which has potential as a human or animal foodstuff. The potential to manage these diseases through intercropping eastern gamagrass with other, non-host perennial species was examined by monitoring incidence and severity on eastern gamagrass within experimental monocultures, two-species mixtures with wildrye ( Leymus racemosus (Lam.) Tsvelev), two-species mixtures with Illinois bundleflower ( Desmanthus illinoensis (Michx.) MacM., Leguminosae), and three-species mixtures with wildrye and Illinois bundleflower at two sites in Kansas, USA, from 1991 to 1995. Wildrye and bundleflower, which are also potential grain crops, are not reported to be hosts of the viruses. At Site 1, in 1991 and 1992, disease was generally less frequent and less severe in biculture with bundleflower and in the three-species mixture than in monoculture or the biculture with wildrye. No treatment effects were observed at Site 2. Disease severity was negatively correlated with plant size and seed yield at Site 1. Seed yield per plant was generally higher in polyculture than in monoculture. The results suggest polyculture may contribute to the management of aphid-borne plant disease within plantings of perennial grains.

Natural Infection of Pearl Millet and Sorghum by Wheat Streak Mosaic Virus in Kansas

Pearl millet (Pennisetum glaucum) and sorghum (Sorghum bicolor) plants at Hays, Kansas, were observed to have viruslike symptoms. Symptomatic plants were tested by enzyme-linked immunosorbent assay (ELISA) against wheat streak mosaic virus (WSMV), maize dwarf mosaic, sugarcane mosaic virus strain MDMV-B, and johnsongrass mosaic virus. Positive reactions were obtained only with WSMV antisera. Pearl millet and sorghum plants (of genotypes naturally infected in the field) mechanically inoculated in the greenhouse developed symptoms and were positive in ELISA for WSMV. The virus was vectored by wheat curl mites (Aceria tosichella) from pearl millet and sorghum to the host from which it was obtained and to wheat. Mechanical inoculation of several sorghum lines showed that the WSMV isolates differed in ability to infect sorghum, and the type specimen could not infect any of the sorghum lines. These results indicated that WSMV occurring at Hays can infect sorghum and pearl millet, crop plants not reported previously as susceptible to WSMV.

Cross-Protection Studies Between Strains of Sugarcane Mosaic, Maize Dwarf Mosaic, Johnsongrass Mosaic, and Sorghum Mosaic Potyviruses

Cross-protection was studied between strains of viruses comprising the sugarcane mosaic virus (SCMV) subgroup, namely Johnsongrass mosaic, maize dwarf mosaic, sorghum mosaic, and SCMV, in 53 different combinations using differential hosts and Western blot immunoassays, Cross-protection occurred only between SCMV-MDB and SCMV-BC when the former was inoculated first and the latter used as the challenge strain, but neither vice versa nor in any other combinations including the 19 that involved recognized strains of the one virus, SCMV. The unidirectional protection between SCMV-MDB and SCMV-BC and the negative cross-protection results between other strains of SCMV appear to correlate with different sequence motifs present in the hypervariable region of the coat protein N-terminus of the SCMV strains

First Report of Sugarcane Mosaic Virus Strain MB in Venezuela.

First Report of Sugarcane Mosaic Virus Strain MB in Venezuela.

Ability to Transmit Sugarcane Mosaic Virus and Seasonal Phenology of Some Aphid Species (Hemiptera: Aphididae) in the Isis and Bundaberg Districts of Queensland

ABSTRACT Rhopalosiphum maidis (Fitch), Aphis gossypii Glover and Myzus persicae (Sultzer) transmitted the Australian sugarcane strain of sugarcane mosaic virus (SCMV‐SC) in a non‐persistent manner, whereas Melanaphis sacchari (Zehntner), Hysteroneura setariae (Thomas), Hyperomyzus lactucae (L.) and Aphis nerii Boyer de Fonscolombe did not transmit the virus. Calculated transmission rate per aphid was higher (12–16%) when sweetcorn was the source of SCMV‐SC than when sugarcane was the source (2–5%). M. sacchari (a non‐vector) and A. gossypii (a vector) were the most prevalent aphids caught on sticky yellow traps in the Isis and Bundaberg districts in 1989–91. Three vector species, A craccivora Koch, A. gossypii and R. maidis, were trapped mainly in spring, summer and autumn, and a fourth vector species, R. padi (L.) was trapped only in winter. Since vector species were active during all seasons, there is always potential for transmission of SCMV‐SC if host, virus and environmental factors are favourable.

Brachiaria Piligera and Sorghum Verticilliflorum Are Natural Hosts of Two Different Strains of Sugarcane Mosaic Virus in Australia.

In 1985 and 1986, during an outbreak of mosaic in sugarcane in the lsis district of Queensland, Brachiaria piligera (hairy arm grass) with mosaic symptoms was found infected with the sugarcane strain of sugarcane mosaic virus (SCMV-SC). This is the first report of SCMV-SC naturally infecting a host other than sugarcane in Australia. Sorghum verticilliflorum (wild sorghum) with mosaic symptoms in the lsis and nearby coastal districts was always infected by Johnsongrass mosaic virus (JGMV), except at one site in Bundaberg where the sabigrass strain of SCMV (SCMV-Sabi), which does not infect sugarcane, was found. This is the first report of SCMV-Sabi occurring in wild sorghum and in a district distant from Gatton where infected sabigrass occurs normally.

Sugarcane Mosaic Virus Strain Maize Dwarf Mosaic Virus B as a Pathogen of Eastern Gamagrass

Eastern gamagrass (EGG) (Tripsacum dactyloides) is a high-quality, high-production native forage grass with potential as a high-protein, perennial grain crop. We used enzyme-linked immunosorbent assay to test EGG samples for virus infection. Over a 2-yr period, we found five instances of maize dwarf mosaic virus (MDMV) and a high incidence (12 and 72% in 3-mo-old and 5-yr-old plantings, respectively) of sugarcane mosaic virus strain MDMV-B (SCMV-MDMV-B) in experimental breeding nurseries in Kansas. Incidence of SCMV-MDMV-B was higher in older breeding nurseries. SCMV-MDMV-B, but not MDMV, was found in three of 42 natural EGG stands (.)

Serological Differentiation of Maize Dwarf Mosaic Potyvirus Strains A, D, E, and F by Electro-Blot Immunoassay

Antiserum recovered 1 wk after a single immunization (As-1wk) with maize dwarf mosaic potyvirus (MDMV) strain A, D, E, or F reacted strongly with the respective homologous capsid protein but weakly or not at all with the corresponding homologous core-capsid protein in electro-blot immunoassays (EBIA). The antisera also reacted with the heterologous capsid proteins of these strains but not with capsid proteins from other members of the potyvirus group (i.e., sugarcane mosaic virus strain MDB [SCMV-MDB], formerly MDMV-B, and johnsongrass mosaic virus strain O [JGMV-O], formerly MDMV-O []

Susceptibility of Pearl Millet Accessions and Cultivars to Johnsongrass Mosaic and Sugarcane Mosaic Viruses in Queensland.

When 23 accessions of pearl millet growing in 1990 at Gatton, south-eastern Queensland, were examined for virus infection, all accessions had plants with mosaic symptoms. Using sorghum differential test plants, it was shown that Johnsongrass mosaic virus (JGMV) was commonly associated, but one isolate of the sabi grass strain of sugarcane mosaic virus (SCMV) was also obtained. In glasshouse tests where 15 accessions of pearl millet were each inoculated with JGMV and the three Australian strains of SCMV 17 days after sowing, all 15 were infected by JGMV and the sabi grass strain of SCMV. However, only two pearl millet accessions were infected by the Queensland blue couch grass strain of SCMV and 14 with the sugarcane strain of SCMV. JGMV caused an average of 60% decrease in dry matter yield 83 days after sowing, whereas strains of SCMV caused less stunting.

Resistance to the H Strain of Sugarcane Mosaic Virus Among Wild Forms of Sugarcane and Relatives

One hundred and three clones of sugarcane relatives, including Saccharum interspecific hybrids, were inoculated with the H strain of sugarcane mosaic virus (SCMV) in two greenhouse experiments. Wild relatives included Erianthus spp., S. spontaneum, S. barberi/S. sinense, S. officinarum, and S. robustum. Among the six taxa represented in the first experiment, Erianthus, S. spontaneum, and S. barberi/S. sinense clones were the most resistant and S. robustum clones were the most susceptible, with the interspecific hybrid and S. officinarum clones intermediate (.)

Differentiation of potyviruses and their strains by hybridization with the 3′ non-coding region of the viral genome

Nucleic acid hybridization with the 3' non-coding region of the potyvirus genome as the probe was shown to be a relatively simple means of distinguishing between distinct potyviruses and their strains. Comparisons of the nucleotide sequences of potyvirus genomes (ignoring gaps) showed that the degree of identity between equivalent genes of strains was greater than 96%, while between distinct potyviruses the identity ranged from 42% to 65%, suggesting that any extended sequence could be considered representative of the whole genome and be suitable as a diagnostic probe. The comparisons however, also revealed that some parts of the genome, but not the 3' non-coding region, had local regions of high sequence identity that could lead to cross-hybridization between distinct potyviruses. For this reason, and because its location immediately upstream of the poly(A) tail makes it the most accessible region for the purposes of cloning and sequencing, the 3' non-coding sequence should be most suitable for use as a diagnostic probe. Successful hybridizations (using radiolabeled, polymerase chain reaction-amplified 3' non-coding sequences) have been achieved by probing recombinant clones, purified potyviral RNA, partially purified total RNA from infected plants, and a crude extract of infected plant tissue. The method has been used to support the proposals that watermelon mosaic virus 2 and soybean mosaic virus-N are both strains of the same virus, and to discriminate between several isolates previously believed to be strains of sugarcane mosaic virus. The method should have wide application as a means of differentiating distinct potyviruses from strains.

Symptom Response of Sorghum Hybrids Infected by Sugarcane Mosaic Virus Strain MDMV-B (1992)

Symptom Response of Sorghum Hybrids Infected by Sugarcane Mosaic Virus Strain MDMV-B (1992)

Unexpected sequence diversity in the amino-terminal ends of the coat proteins of strains of sugarcane mosaic virus

The sequence of the 3'-terminal 1343 nucleotides of the SC strain of the sugarcane mosaic virus (SCMV-SC) genome was compared with the 1376 nucleotides at the 3' terminus of maize dwarf mosaic virus B (MDMV-B). The SCMV-SC sequence includes an open reading frame which codes for the viral coat protein of 313 amino acids (nucleotides 157 to 1116), followed by a 3' non-coding region of 235 nucleotides and a poly(A) tail. The MDMV-B sequence codes for the capsid protein (nucleotides 157 to 1139) of 328 amino acids and has a 3' non-coding region of 236 nucleotides. The coat protein of SCMV-SC has 92% identity with that of MDMV-B except for the region between amino acid residues 27 and 70 of SCMV-SC. This region of SCMV-SC is smaller (44 residues) than the equivalent region in MDMV-B (59 residues) and has only 22% identity with the MDMV-B sequence. Possible mechanisms for the generation of this sequence diversity are discussed. Despite this diversity, the sequence identities of both the major part of the coat proteins and the 3' non-coding regions confirm the proposal, based on previously described serological data, that SCMV-SC and MDMV-B are strains of SCMV.

Confirmation that the Sugarcane Mosaic Virus Subgroup Consists of Four Distinct Potyviruses by Using Peptide Profiles of Coat Proteins

The taxonomic status of sugarcane mosaic virus (SCMV) strains reported from various parts of the world has been uncertain. Previous analyses of 17 SCMV strains with virus-specific polyclonal antibodies demonstrated that they represent four distinct potyviruses, namely Johnsongrass mosaic virus (JGMV), maize dwarf mosaic virus (MDMV), sorghum mosaic virus (SrMV), and SCMV. To confirm this classification, we have now compared six strains of SCMV, three strains of JGMV, and two strains each of MDMV and SrMV using high-performance liquid chromatographic (HPLC) peptide profiling of tryptic digests of their coat proteins (...)

Coat Protein Properties Indicate That Maize Dwarf Mosaic Virus-KS1 Is a Strain of Johnsongrass Mosaic Virus

It has recently been shown that 17 potyvirus isolates infecting maize, sorghum, and sugarcane in Australia and the United States, and previously classified as strains of sugarcane mosaic virus (SCMV), belong to four distinct potyviruses. However, the taxonomic status of other SCMV strains is uncertain at present. Using amino acid composition, high-performance liquid chromatographic peptide profiling of tryptic digests, partial amino acid sequence data, and electro-blot immunoassay of coat proteins, we confirm that the oat-infecting strain of maize dwarf mosaic virus (MDMV-O) from the United States is structurally and serologically closely related to the Australian johnsongrass strain of johnsongrass mosaic virus (JGMV-JG) (...)

Coat protein of Potyviruses

Three strains of passionfruit woodiness virus, Tip Blight (PWV-TB), Severe (PWV-S) and Mild (PWV-M), were compared on the basis of their biological, serological and coat protein structural properties. Each of the strains could be distinguished on the basis of their reactions on selected test plant species but no differences were observed in the serological properties of the three PWV strains. Molecular weight estimates on SDS-PAGE suggest the PWV coat protein contains 275 amino acid residues and sequence data for 269 of these residues is presented. The amino terminal peptide is blocked and has not been sequenced. The coat proteins of PWV-TB and PWV-S, which cause severe symptoms in infected plants, showed only three sequence differences compared to the eleven or twelve sequence changes between their coat proteins and that of the mild strain. The high sequence homology (96-99%) between the three PWV strains is similar to that previously reported for two strains of tobacco etch virus and three strains of sugarcane mosaic virus. Sequence homology between the three strains of PWV and published sequences for the coat proteins of eight distinct potyviruses ranged from 43-71% (average 57%).

Influence of Sugarcane Mosaic Virus on Segregation for Two Seedling Characteristics in Sorghum

Sorghum (Sorghum bicolor L., Moench) yields are reduced in many areas by the sugarcane mosaic virus. Losses from pathological effects of the virus have been documented; information about genetic effects could lead to improved production practices and more efficient breeding programs. Our objectives were to determine whether the sugarcane mosaic virus strain A (SCMV‐A) in one of the parent plants of a sorghum cross could influence segregation for seedling color and ligule expression in later generations, and whether segregation of this type could be detected and evaluated by phenotypic observations. In tests under greenhouse conditions, deviations in segregation of four phenotypes in F2 populations of reciprocal control crosses were not significant. Segregation of F2 plants into four phenotypes in control and treated (T) (one virus‐infected parent) populations was significantly different from expected ratios in the cross ‘Planter’ (T) × ‘MN4611’, at the 5% level, and at the 1% level in Planter × MN 4611 (T). Deviations in distribution of nine F2 genotypes within treated populations, observed in F3 seedlings, of the cross Planter × MN 4611, were significant at the 5% level and in MN 4611 × Planter at the 1% level. Also, deviations in distribution of F2 genotypes from expected ratios in populations from control and treated crosses, were significant at the 1% level in MN 4611 × Planter. Although SCMV‐A in one of the parent plants did not produce recognizable virus symptoms in F1, F2, or F3 populations; it was associated with deviations of F2 genotypes from expected ratios.