• Research in Plant Disease
• /
• v.19 no.2
• /
• pp.77-83
• /
• 2013

Bean yellow mosaic virus (BYMV; genus Potyvirus, family Potyviridae) causes severe losses to various legume species and a number of non-legume species, particularly freesia plants. In a survey of virus diseases in Gyeonggi province, Korea, BYMV isolates were identified from many cultivated freesia species. Here, we determined the complete nucleotide sequences of a BYMV freesia isolate (BYMV-Fr; accession number FJ492961). BYMV-Fr genome consists of 9,545 nucleotides (nt) excluding the poly (A) tail and encodes 3,057 amino acid (aa), with an AUG start and UAG stop codon, containing one open reading frame typical of a potyvirus polyprotein. The polyprotein of BYMV-Fr was divided to ten proteins and the cleavage sites of each protein were determined. The coat protein (CP) and polyprotein of BYMV-Fr were compared at the aa level with those of the previously reported 4 BYMV isolates. BYMV-Fr shared 90.1 to 97.1 and 91.0 to 92.5% at the CP and polyprotein homology. Interestingly, BYMV-Fr showed identities of a lower level at the nt level of 5' noncoding region (61.4 to 67.6%) and at the aa level of P1 (71.4 to 72.8%), comparing with four BYMV isolates. Based on the aa sequence diversity of CP and polyprotein, phylogenetic analysis with the four BYMV isolates showed two distinct groups and BYMV-Fr and most BYMV isolates were most closely related to the clover yellow vein virus among 52 potyviruses. To our knowledge, this is the first report of the complete genome sequence of BYMV freesia strain.

• Korean Journal Plant Pathology
• /
• v.14 no.1
• /
• pp.74-82
• /
• 1998

Gladioli (Gladiolus hybridus) showing flower colour breaking, leaf mosaics, necrotic fleck, and dwarfing or lack of visible symptoms were collected from gladioli growing areas in Taegu and Kyungpook province, Korea. The two viruses isolated from the naturally infected gladioli were identified as ban yellow mosaic virus (BYMV) and clover yellow vein virus (CIYVV) by their host range, immunosorbent electron microscopy (ISEM), enzyme-linked immunosorbent assay (ELISA), direct tissue blotting immunoassay (DTBIA) and intracellural symptoms. In ultrathin sections of BYMV and CIYVV infected tissues, laminated aggregate-type inclusions, cytopalsmic bodies and nuclear inclusions as well as filamentous virus particles were observed in the cytoplasm of parenchyma cells. By DTBIA and ISEM, BYMV was detected in all tested gladiolus plants showing severe or mild mosaic symptoms, whereas CIYVV were mainly detected from those of mild mosaic symptoms. BYMV is the most prevalent in commercial gladioli and present major production problems. Detection sensitivity of BYMV and CIYVV in crude sap of infected gladiolus leaves by ISEM was about twice compared with ELISA. In a comparison of ELISA, ISEM, DTBIA, BYMV was detected in same degree by DTBIA in samples where sap extracts were positive in both ELISA and ISEM. DTBIA provides a specific, rapid, and simple tool for large-scale diagnosis of BYMV.

• Korean journal of applied entomology
• /
• v.22 no.3 s.56
• /
• pp.198-202
• /
• 1983

A mosaic disease of gladiolus has been commonly observed with an infection rate of $43.3\%$ in the field. Bean Yellow Mosaic Virus(BYMV) produced veinal spreading lesions on Cheonopodium amaranticolor, veinal necrosis and severe leaf distortion on Phaseolus vulgaris 'Scotia' and mosaic on Vi cia faba. Cucumber Mosaic Virus(CMV) produced local lesions on C. amaranticolor, mosaic symptoms on Nicotiana glutinosa and Cucumis sativus. BYMV and CMV were transmitted by the green peach aphid. Purified BYMV and CMV had a typical maximum absorption at 260nm. In agar gel diffusion test, BYMV and CMV gave positive reaction with their homologous antiserum. The size of BYMV was 750nm in length, and CMV was 30nm in diameter.

• Applied Microscopy
• /
• v.20 no.1
• /
• pp.120-127
• /
• 1990

The zoospores of Polymyxa graminis known as vector of barley yellow mosaic virus(BYMV) were found from the rootlets of diseased barley plants. The X-bodies in the lower epidermis of diseased leaf tissues were reddish under fluorescence microscopy. The shape of virus particles was flexuous rod and 300-1,000 nm in length. The pinwheel structures, cylindrical inclusion bodies, ring-form inclusion bodies, and crystalline lattice-like structure were found together with virus particles in the cytoplasm of diseased leaf tissues. Generally, intracellular organelles in the diseased barley leaf tissues infected with BYMV were either not well-developed or degenerated.

• Korean Journal Plant Pathology
• /
• v.2 no.1
• /
• pp.48-52
• /
• 1986

The virus isolated from white clover, Trifolium repens showing mosaic symptom was identified as bean yellow mosaic virus (BYMV) based on the host range, physical properties, aphid transmission, serology and morphology of the virus particles. Chenopodium amaranticolor and C. quinoa produced local lesions on the inoculated leaves and chlorotic spot on the upper leaves. Broad bean and cowpea produced local lesions on the inoculated leaves and mosaic with vein necrotic symptoms on the upper leaves. French bean showed vein necrosis on the inoculated leaves, yellow mosaic on the upper leaves and bud blight. The average size of virus particles was 740nm in length. The virus was also transmitted by Myzus persicae. The thermal inactivation point of the virus isolate was $60\;to\;65^{\circ}C$, the dilution end point $10^{-3}\;-\;10^{-4}$ and the longevity in vitro was 3 days Serological tests with the virus purified from Trifolium repens were positive to BYMV antiserum.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.53 no.4
• /
• pp.427-433
• /
• 2008

Barley Yellow Mosaic Virus (BaYMV) caused significant reduction in barley yield and is difficult to control due to alive parasitic soil-borne fungus, Palmyra gamines that transmits the, virus. Previous studies have indicated that a virus-free soil could be infested by using virus-contaminated farming machineneries and implements. For the further confirmation of this finding, different proportions of BaYMV-infested soil were mixed into virus free soil. Three barley varieties (Hordum vulgarae, cv "Olbori", "Baegdong" and "Sacheon 6") were sown in pots treated with different rate of P. graminis-infested soil ranging from 0% to 100% in October 20, 2001. Results showed that BaYMV infection increased as the rate of infested soil increased. Initial symptoms were observed in a pots treated with 10% infested soil in all the 3 varieties of barley. "Olbori" had about 5% infection in 20% infested soil and about 10% infection in 40% or 50% infested soil and about 20% infection in 60% infested soil. In "Baegdong", the trend of BYMV occurrence was similar with "Olbori" but the time of severe infection was earlier than "Olbori". BaYMV infection in "Sacheon 6" was even earlier than "Baegdong" with much more severe symptoms than "Baegdong". The growth rate of barley was affected by about 19-22% when grown in 20% infested soil. As the rate of BaYMV infested soil increased the heading date was delayed but the maturing date was early in "Olbori" and "Sacheon 6". Also, reduction rate of culm length in 3 varieties increased with increase of infested soil content. However, "Olbori" showed the highest reduction. "Sacheon 6", have been characterized with long spike length, however was significantly reduced as the infested soil increased. On the other hand, spike length of "Olbori" was not significantly affected despite of increased of infested soil. The reduction rate of 1000 kernel weight was higher in large kernel size cultivar "Sacheon 6" and "Olbori" than small kernel size "Baegdong" as increase of BaYMV-infested soil content.