• Toxicological Research
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• v.19 no.1
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• pp.1-12
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• 2003

New breeding method by genetic engineering is expected as a key technology to solve food shortage due to the growing world population in the year 2000s. Many genetically modified organisms (GMOs) were already developed and the commercial cultivation had started. The first GMO, Flavr Savr tomato, which rotted at a much slower pace than ordinary ones, was developed in US in 1994. Since then, over than 70 different agricultural products including corn, cotton, soybean, papaya, potato, and squash made with genetically modified plants are reportedly on sale worldwide. Supporters favor the GMOs because they have greater yields, longer shelf lives and stronger resistance to disease and insects. On the other hand, opponents say that the supporters ignore a potential danger that they may damage the environment as well as human beings. To assure the safe development and use of GMOs as food and other biotech products, the possible risks on biological environment and human health should be throughly examined and regulated by developer and government. Because the biosafety problem is a global, environmental, and trade issue, a new international treaty is under development. The Cartagena Protocol on Biosafety was adopted at the 1 st Extraordinary Conference of Parties of the Convention on Biological Diversity which was held at Mont-real, Canada, Jan. 29th, 2000. The adoption of the Protocol is seen as a breakthrough in that it is based on the" Precautionary Principle" despite scientific uncertainties surrounding potential risks that GMOs may inflict on human health and the environment and that it has laid the ground for introduction of specific steps to handle international trading of GMOs. In this paper, the authors would like to introduce the current status and perspective of environmental and human risk assessment of GMOs.t of GMOs.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.176-184
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• 2016

Background: Wild ginseng, Panax ginseng Meyer, is an endangered species of medicinal plants. In the present study, we analyzed variations within the ribosomal DNA (rDNA) cluster to gain insight into the genetic diversity of the Oriental ginseng, P. ginseng, at artificial plant cultivation. Methods: The roots of wild P. ginseng plants were sampled from a nonprotected natural population of the Russian Far East. The slides were prepared from leaf tissues using the squash technique for cytogenetic analysis. The 18S rDNA sequences were cloned and sequenced. The distribution of nucleotide diversity, recombination events, and interspecific phylogenies for the total 18S rDNA sequence data set was also examined. Results: In mesophyll cells, mononucleolar nuclei were estimated to be dominant (75.7%), while the remaining nuclei contained two to four nucleoli. Among the analyzed 18S rDNA clones, 20% were identical to the 18S rDNA sequence of P. ginseng from Japan, and other clones differed in one to six substitutions. The nucleotide polymorphism was more expressed at the positions 440-640 bp, and distributed in variable regions, expansion segments, and conservative elements of core structure. The phylogenetic analysis confirmed conspecificity of ginseng plants cultivated in different regions, with two fixed mutations between P. ginseng and other species. Conclusion: This study identified the evidences of the intragenomic nucleotide polymorphism in the 18S rDNA sequences of P. ginseng. These data suggest that, in cultivated plants, the observed genome instability may influence the synthesis of biologically active compounds, which are widely used in traditional medicine.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2007-2017
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• 2016

Background: Modifying lifestyle factors such as diet and exercise can reduce the risk of cancer. Psychological stress (PS) might be indirectly associated with cancer because it alters lifestyle factors. However, the relationship among these variables has not been fully investigated. Thus, we examined interactions between self-reported PS (SRPS) and habitual exercise on diet. Materials and Methods: In all, 5,587 men and 2,718 women were divided into "exerciser" and :non-exerciser" groips, based on whether they exercised reguarly, and classified into three SRPS levels: low, moderate and high. Diet was estimated using a validated food frequency questionnaire. Using a general linear model, food and nutrient consumption was estimated for each SRPS level in the 2 exercise groups, and the interactions between SRPS levels and exercise were calculated. Results: In women, the intake of pork and beef, low fat milk and yogurt, natto (fermented soybean), carrots and squash, other root vegetables, mushrooms, seaweeds, and wine along with the nutrients vegetable protein, soluble, insoluble and total dietary fiber, daidzein, genistein, carotene, retinol equivalents, vitamin B2, pantothenic acid, potassium, calcium, magnesium, phosphorus and iron demonstrated significant interaction with SRPS and habitual exercise (p for interaction <0.05). In men, raw and green leafy vegetable and fruit and vegetable juice significantly interacted with SRPS and habitual exercise (p for interaction <0.05). Conclusions: We suggest that certain foods and nutrients, which are thought to have a protective effect against cancer, interact with SRPS and habitual exercise, especially in women. This information is valuable for understanding and improving interventions for cancer prevention.

• Parasites, Hosts and Diseases
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• v.48 no.3
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• pp.213-217
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• 2010

Sarcocystis sp. infection was investigated in 20 necropsied captive wild mammals and 20 birds in 2 petting zoos in Malaysia. The gross post-mortem lesions in mammals showed marbling of the liver with uniform congestion of the intestine, and for birds, there was atrophy of the sternal muscles with hemorrhage and edema of the lungs in 2 birds. Naked eye examination was used for detection of macroscopic sarcocysts, and muscle squash for microscopic type. Only microscopically visible cysts were detected in 8 animals and species identification was not possible. Histological examination of the sections of infected skeletal muscles showed more than 5 sarcocysts in each specimen. No leukocytic infiltration was seen in affected organs. The shape of the cysts was elongated or Circular, and the mean size reached $254{\times}24.5{\mu}m$ and the thickness of the wall up to $2.5{\mu}m$. Two stages were recognized in the cysts, the peripheral metrocytes and large numbers of crescent shaped merozoites. Out of 40 animals examined, 3 mammals and 5 birds were positive (20%). The infection rate was 15% and 25% in mammals and birds, respectively. Regarding the organs, the infection rate was 50% in the skeletal muscles followed by tongue and heart (37.5%), diaphragm (25%), and esophagus (12.5%). Further ultrastructural studies are required to identify the species of Sarcocystis that infect captive wild animals and their possible role in zoonosis.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.77-83
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• 1999

In 1997 surveys 82 out of 180 crucifer fields were infected with clubroot disease in a range of 1-100% of diseased plants and among crucifier crops Chinese cabbage was the most severe, In cropping systems Chinese cabbage-monocropping of Chinese cabbage-radish were found to be most common in major Chinese cabbage production areas. Welsh onion squash or paddy rice were also planted between cropping of Chinese cabbage. Paddy fields converted to upland were lowered in incidence of clubroot disease and fields with loam to silty loam soil were more severe in disease than those with sandy soil. Soil pH and organic contents were nor related to clubroot disease severity. Soil fauua such as total fungi bacteria actinomyces Pseudomonads and Bascillus were not correlated with severity of the disease. Root rall development on Chinese cabbage seedlings was initifially observed under a microscope 13 days after inoculation with Plasmodiophora brassicae but 18 days by naked eyes after inoculation. Root galls were formed mostly around collar roots and gradually spread to main root lateral roots and secondary root branches. Root galls started to enlarge greatly in size and weight from 23 days after inoculation. Chinese cabbage plants at mid-growth stage with root gall development were reduced to 1/2 of that of healthy plants in number of leaves 1/4-1/5 in above ground fresh weight 1/6 in root length but increased to 3 times in diameter of collar root. Diseased plants had little root hairs. Diseased Chinese cabbage plants at harvest were reduced by 9,1-11.8% in head weight compared to healthy plants a positive correlation was observed between root and head weight but those relationships were rot found in the diseased plants.

• The Plant Pathology Journal
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• v.18 no.3
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• pp.121-125
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• 2002

This study was conducted to determine the causal virus that naturally infected hollyhock (Althaea rosea) plant showing mild mosaic symptom in 1999. Flexuous virus particles were found in the cytoplasm of plant tissue from infected hollyhock under transmissible electron microscopy. A virus from the genus Potyvirus under the family Potyviridae was isolated and was maintained on Chenopodium quinoa for three passages. Chlorotic local legions were used to inoculate 20 species of indicator plants. The virus infected all the tested cucurbit plants, but failed to infect Nicotiana benthamiana. Based on the host range test and RT-PCR analysis, the potyvirus was identified as a strain of Zucchini yellow mosaic virus-A (ZYMV-A), one of the major pathogens of cucurbits. Infectivity analysis showed that ZYMV-A induced faster systemic symptom than ZYMV-Cu on squash and other cucurbit plants, suggesting that ZYMV-A was a more severe strain. To better characterize ZYMV-A, Western blot assay was carried rout to the coat protein (CP) of the virus using ZYMV-specific antiserum with ZYMV-Cu and other potyviruses. The CP of the virus reacted strongly with the antiserum against ZYMV, and other tested antisera did not react with the CP of ZYMV-A. Results strongly suggest that the potyvirus infecting hollyhock was a novel strain of ZYMV. This is the first report on ZYMV as the causal virus infecting hollyhock in Korea.

• Research in Plant Disease
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• v.13 no.2
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• pp.82-87
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• 2007

The genetic diagnostic method of virion capture (VC)/RT-PCR was developed for the simultaneous detection of three rod shaped viruses of Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus(KGMMV) and Zucchini green mottle mosaic virus (ZGMMV) transmitted by seed in Cucurbit. Out of 12 primer combinations for the three tobamoviruses, a primer set of CGMMV-C724, KGMMV-K513 and ZGMMV-Z407A was useful for mono and triplex VC/RT-PCR. The triplex VC/RT-PCR for the three tobamovirus in Cucurbit could detect specifically without interference among primers and/or plant species of watermelon, gourd, cucumber, melon, pumpkin, squash and Nicotiana benthamiana.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.251-259
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• 2007

Two isolates of Cucumber mosaic virus (CMV) originated from lily plants, named Ly2-CMV and Ly8-CMV, were compared with their pathological features in several host plants. Ly2-CMV and Ly8-CMV could induce systemic mosaic symptom in Nicotiana benthamiana, but Ly2-CMV could not systemically infect tomato and cucumber plants that have been used for CMV-propagative hosts. While Fny-CMV used as a control infected systemically the same host plants, producing typical CMV symptoms. Ly8-CMV could infect systemically two species of tobacco (N. tabacum cv. Xanthi-nc and N. glutinosa) and zucchini squash (Curcubita pepo), but Ly2 failed systemic infection on these plants. As resulted from tissue-print immunoblot assay, different kinetics of systemic movement between Ly2-CMV and Ly8-CMV were crucial for systemic infection in tobacco (cv. Xanthi-nc). Sequence analysis of full-length genome of two lily isolates showed Ly2 and Ly8 belonged to subgroup IA of CMV. The lily isolates shared overall 98 % sequence identity in their genomes. Coat protein, 3a protein, and 2b protein involved in virus movement was highly conserved in genomes of the isolates Ly2 and Ly8. Although there is the low frequency of recombinants and reassortants in natural CMV population, phylogenetic analysis of each viral protein among a number of CMV isolates suggested that genetic variation in a defined population of CMV lily isolates was stochastically produced.

• Research in Plant Disease
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• v.14 no.3
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• pp.229-232
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• 2008

An isolate of Cucumber mosaic virus (CMV), designated as Cas-CMV, was isolated from Chinese aster (Callistephus chinensis) showing severe mosaic symptom, and its properties was compared to the well-characterized Fny-CMV (subgroup IA) and As-CMV (subgroup IB) by host reaction in several indicator plants, dsRNA analysis, RT-PCR analysis, and restriction enzyme profile of the PCR products. Cas-CMV differed markedly in their host reaction to Fny-CMV or As-CMV in Cucurbita pepo cv. Black beauty. In the zucchini squash, all strains induced chlorotic spot on inoculated leaves and mosaic symptoms on upper leaves. However, symptoms induced by Cas-CMV were developed lethal necrosis on the young plants 15 to 20 days after inoculation. In experiments of dsRNA analysis and RT-PCR analysis, properties of Cas-CMV was come within subgroup I CMV. Moreover, restriction enzyme analysis using HindIII of the RT-PCR products showed that Cas-CMV belong to a member of CMV subgroup IA.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.614-622
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• 2014

Melons (Cucumis melo L.) are generally grafted onto Cucurbita rootstocks to manage soilborne pathogens such as Monosporascus root rot and v ine decline (MRR/VD) and Fusarium wilt. However, g rafting onto Cucurbita rootstocks reportedly results in the reduction of fruit quality. In this study, the resistance to MRR/VD, yield, and fruit quality of melons grafted onto melon rootstocks were evaluated under greenhouse conditions. Eight melon rootstocks (R1 to R8) were used and the inodorus melon 'Homerunstar' was used as scion. Melon rootstocks R1 to R6 were selected based on resistance to MRR/VD under greenhouse conditions. Non-grafted 'Homerunstar' and plants grafted onto squash interspecific hybrid 'Shintozwa' rootstock (Cucurbita maxima D. ${\times}$ C. moschata D.) served as controls. Grafted melons were cultivated in the greenhouse infested with Monosporascus cannonballus during two growing seasons (summer and autumn). The responses to MRR/VD, yield, and fruit quality differed depending on the rootstocks and growing season. The melons grafted onto 'Shintozwa' exhibited less severe disease symptoms and higher survival rates than non-grafted melons in both seasons. While the melon rootstocks in the summer cultivation did not increase the survival rate compared to non-grafted melons, the melon rootstocks R1 and R2 in the autumn cultivation led to higher survival rates. The melon rootstocks resistant to MRR/VD increased the percentage of marketable fruits and marketable yields. Grafting onto the melon rootstocks caused little or no reduction of fruit quality such as low calcium content, fruit softening, and vitrescence, especially in lower-temperature autumn season. Accordingly, these results suggest that grafting onto the melon rootstocks may increase the tolerance to MRR/VD and the marketable yield without a reduction of fruit quality.