• The Plant Pathology Journal
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• v.19 no.3
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• pp.133-137
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• 2003

Seedborne fungus Bipolaris spicifera, which has not been previously reported in Korea, was detected from import-ed grass seeds in the country. The most frequently detected fungi from the seeds were Fusarium species, Ulocladium atrum, B. spicifera, Alternaria, and Cuvularia lunata among 17 different seed samples of the family Gramineae. Detection frequencies of B. spicifera were 11,8,5% in Bermuda grass, tall fescue, and mixed lawn grass imported from USA, respectively, and 9％ in mixed lawn grass imported from Italy. This suggests that important seedborne pathogen could be spread between countries through seed sources. The pathogen was seed-transmitted causing damping-off of Bermuda grass seedlings and showed strong pathogenicity to vice, corn, Bermuda grass, sorghum, and tall fescue. However, it did not infect wheat and blue grass.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.280-284
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• 1984

Association of SMV infection in soybean plants with seedcoat mottling and with seed transmission of SMV was examined. Seedcoat mottling was increased positively in proportion to the SMV severity in variety Clark. No correlation was found between the incidence of mottled seed and the seed's position on the plant. Susceptible variety with virus symptoms gave rise to mottled seeds but only a small percentage of these mottled seeds could transmit the virus. SMV could be transmitted even by nonmottled seeds harvested from SMV infected plants in similar rate with mottled seed. It seemed that the amount of mottled seed could be used as an indicator of the amounts of SMV infection in a seed production field.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.217-223
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• 1995

Nature of graft transmissibility of pear abnormal leaf spot disease was examined by various grafting methods in the greenhouse and field. When the diseased and symptomless twigs were collected in winter and grafted in the next spring to the seed-originated healthy root stock, the abnormal leaf spot was developed only in the case of the diseased twigs. Double grafting on a seed-originated healthy root stock, where the diseased and the symptomless twigs were used as 1st and 2nd scions, respectively, developed abnormal leaf spot lesions without exception on the 2nd scions. Tongue-graft with the diseased and the symptomless trees also incited abnormal leaf spots on the both trees. Abnormal leaf spots of were also developed on HN-39, an indicator pear tree, used as a 2nd scion in a double graft test, where the diseased twig and a seed-originated healthy tree were used as the 1st scion and the root stock, respectively. When the diseased twig was top-grafted to the healthy root stock, lesion development of abnormal spot was limited to the grafted twig itself in the 1st year, but expanded to the main branches in the 2nd year, and spread over the whole tree in the 3rd year. This result indicates that the causal agent of abnormal leaf spot disease is transmitted by graft.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.424-428
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• 2017

Tomato yellow leaf curl virus (TYLCV) infection of the common bean (Phaseolus vulgaris) has been reported, but soybean (Glycine max) has not previously been identified as a TYLCV host. Five cultivars of white soybean were agro-inoculated using an infectious TYLCV clone. At 30 days post-inoculation, they showed infection rates of 25% to 100%. Typical TYLCV symptoms were not observed in any inoculated plants. To examine whether TYLCV was transmitted in soybean seeds, DNA was isolated from bundles of five randomly selected seeds from TYLCV-inoculated soybean plants and amplified with a TYLCV-specific primer set. With the exception of one bundle, all bundles of seeds were verified to be TYLCV-infected. Virus dissemination was also confirmed in three of the 14 bunches. Viral replication was also identified in seeds and seedlings. This is the first report demonstrating that soybean is a TYLCV host, and that TYLCV is a seed-transmissible virus in white soybean.

• The Plant Pathology Journal
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• v.38 no.4
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• pp.334-344
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• 2022

Bacterial wilt is a re-emerging disease on dry bean and can affect many other crop species within the Fabaceae. The causal agent, Curtobacterium flaccumfaciens pv. flaccumfaciens (CFF), is a small, Gram-positive, rod-shaped bacterium that is seed-transmitted. Infections in the host become systemic, leading to wilting and economic loss. Clean seed programs and bactericidal seed treatments are two critical management tools. This study characterizes the efficacies of five bactericidal chemicals against CFF. It was hypothesized that this bacterium was capable of forming biofilms, and that the cells within biofilms would be more tolerant to bactericidal treatments. The minimum biocide eradication concentration assay protocol was used to grow CFF biofilms, expose the biofilms to bactericides, and enumerate survivors compared to a non-treated control (water). Streptomycin and oxysilver bisulfate had EC95 values at the lowest concentrations and are likely the best candidates for seed treatment products for controlling seed-borne bacterial wilt of bean. The results showed that CFF formed biofilms during at least two phases of the bacterial wilt disease cycle, and the biofilms were much more difficult to eradicate than their planktonic counterparts. Overall, biofilm formation by CFF is an important part of the bacterial wilt disease cycle in dry edible bean and antibiofilm bactericides such as streptomycin and oxysilver bisulfate may be best suited for use in disease management.

• Research in Plant Disease
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• v.9 no.1
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• pp.1-9
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• 2003

The occurrence of potato(Sotanum tuberosum) viral diseases caused by Potato virus X(PVX), Potato virus Y (PVY), Potato leafroll virus(PLRV), Potato vims S(PVS), Potato virus M(PVM), Potato virus A(PVA), Potato virus T(PVT), Alfalfa mosic virus(AIMV), Tobacco mosic virus(TMV), Potato mop top virus(PMTV) Tobacco rattle virus(TRV) and Potato spindle tuber viroid(PSTVd), potato witches' broom phytoplasma, have been identified so far in Korea. Major viral diseases such as PVX, PVY and PLRV had been studied more deeply, however, the others are just identified and only partially characterized since the first study on the relation between PVX nucleic acid and virus protein by Kim in 1961. The most studies on potato viral diseases are mainly focused on the problems of seed potato production. The National Alpine Agricultural Experiment Station(NAAES), since it began its activities in 1961, has given special attention to this problem by doing studies to identify, characterize and control potato virus diseases. This effort resulted in the development of new potato virus detection methods as a basis for elaborating new method of control, such as the production of seed potato free of virus and the selection of new virus-resistant transgenic potatoes. The further studies of potato viral diseases required would be fallowings: the continuous monitoring for the occurrence of identified or not identified potato viruses in Korea, the isolation of resistant viral genes, the development of control method for the non-persistently transmitted viruses like PVY, special vectors such as nematode and fungus transmitted viruses, TRV and PMTV and the development of control methods against potato viral diseases by viral cross protection, therapy, transgenic plant, and the use of the agents or molecules, such as virus inhibitors and antiviral proteins, etc., blocking viral replication.

• Korean journal of applied entomology
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• v.18 no.3 s.40
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• pp.119-126
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• 1979

From the sample seeds of rice cultivar Palkoeng with the brown spot symptom, Helminthosporium oryzae was detected in $86\~92\%$ of hulls including empty glumes, lemma, palea, and rachilla in five to seven days of incubation. When the seeds were dehulled, the percentage detection decreased to $74\~83\%$ of pericarps. The fungus sporulated on whole surface of the seed and was detected within about ten cell layers deep of endosperm but not detected in embryo. Fusarium moniliforme was found in embryo as well as pericarp and endosperm. The frequency of F. roseum, Trichoconis padwickii, Curvularia spp., Atternaria tenuis, Cladosporium cladosporoides and Phoma sp. was less than three percent of hulls and pericarps. In seven days of incubation, $60\~87\%$ of the germinating seeds showed the symptom of H. oryzae while $13\~40\%$ were apparently healthy. This fungus in hilum of infected rice transmitted through pericarp to plumule shoot and radicle of the germinating seed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3942-3949
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• 2010

Since existing Nate-on Messenger application stores users' personal information in the database of its server, it is extremely venerable to internal threats, not to mention the communication data being transmitted without any safety measures. To solve such problematic areas of the existing application, we have developed a safer messenger application. The messenger application proposed in this paper discloses only the least required personal information of its users and the rest of the personal information is safely encrypted in the database using private passwords. This protective measure prevents the administrator or a third party from misusing the information since he/she will not be able access the information. In addition, users will be able to freely and safely communicate using this new messenger since transmitted data will also be encrypted.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.161-161
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• 2017

Seed endophytes are very remarkable groups of bacteria for their unique abilities of being vertically transmitted and conserved. As plants attain hybrid vigor and heterosis in the process of crossbreeding, this might also lead to the changes in the community structure and diversity of plant endophytes in the hybrid plants ultimately affecting the endophytes of the seeds. It would be interesting to characterize how seed endophyte composition change over time. The objective of this study is to gain insights into the influence of natural crossbreeding and parental lineage in the seed bacterial endophytic communities of two pure inbred lines exploring contributions of the two most important sources of plant endophytes - colonization from external sources and vertical transmission via seeds. Total genomic DNA was isolated from rice seeds and bacterial DNA was selectively amplified by PCR. The diversity of endophytic bacteria was studied through Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Diversity between the original parents and the pure inbred line may show significant differences in terms of richness, evenness and diversity indices. Heat maps reveal astonishing contributions of both or either parents (IR29 ${\times}$ Pokkali and AT401 ${\times}$ IR31868) in the shaping of the bacterial seed endophytes of the hybrid, FL478 and IC32, respectively. Most of the T-RFs of the subsequent pure inbred line could be traced to any or both of the parents. Comparison of common and genotype-specific T-RFs of parents and their offspring reveals that majority of the T-RFs are shared suggesting higher transmission of bacterial communities common to both parents. The parents influence the bacterial community of their offspring. Unique T-RFs of the offspring also suggest external sources of colonization particularly as the seeds are cultivated in different ecogeographical locations. This study showed that host parental lines contributed greatly in the shaping of bacterial seed endophytes of their offspring. It also revealed transmission and potential conservation of core seed bacterial endophytes that generally become the dominant microbiota in the succeeding generations of plant hosts.

• Mycobiology
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• v.50 no.5
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• pp.382-388
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• 2022

White mold (or Sclerotinia stem rot), caused by Sclerotinia species, is a major air, soil, or seed-transmitted disease affecting numerous crops and wild plants. Microscopic or culture-based methods currently available for their detection and identification are time-consuming, laborious, and often erroneous. Therefore, we developed a multiplex quantitative PCR (qPCR) assay for the discrimination, detection, and quantification of DNA collected from each of the three economically relevant Sclerotinia species, namely, S. sclerotiorum, S. minor, and S. nivalis. TaqMan primer/probe combinations specific for each Sclerotinia species were designed based on the gene sequences encoding aspartyl protease. High specificity and sensitivity of each probe were confirmed for sclerotium and soil samples, as well as pure cultures, using simplex and multiplex qPCRs. This multiplex assay could be helpful in detecting and quantifying specific species of Sclerotinia, and therefore, may be valuable for disease diagnosis, forecasting, and management.