• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.55-62
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• 1994

The germplasms of naked barley evaluated for starch content were 137 crossing blacks and progeny lines obtained from the breeding program of the Wheat and Barley Research Institute, 540 Tabdong Kwonsungu Suwon, in the 1988/1989 season. Starch content was distributed between 49.15 and 62.50% with a mean of 57.20%. It was high in the bred lines and the Uz type lines than the imported, uz type or lax type ones. The range observed for seed coat weight was 1.12-3.02mg and the mean seed coat weight was 1.88mg. The seed coat weight ratio to kernel weight was measured between 4.0 and 8.7% with a mean of 6.5%. The varieties differ greatly in the characteristics depending on the plant type and origin of germplasms. The variation observed with protein content ranged from 9.60 to. 15.90% while the average was 12.86%. Starch content was negative relationships with kernel weight, seed coat weight, seed coat weight ratio., kernel width, kernel thickness and protein content, and starch content was higher in smaller kernels within a variety. The weight and weight ratio. of seed coat were positively correlated with the width, thick-ness of kernels, whilst they were negatively correlated with starch content. The heritability of starch content was 30.0%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.398-410
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• 1982

Summer crops grown in uplands are greatly diversified and show a large variation in difference with year and location in Korea. The principal factor for the variation is weather, in which precipitation and temperature play a leading role and such a weather factors as wind, sun lights also influence production of the summer crops. Since artificial control of weather conditions as a main stress factor for crop production is almost impossible, it must be minimized only by an improvement of cultivation techniques and crop improvement. Precipitation plays a role as one of the most important factor for production of the summer crops and it is considered in two aspects, drought and excess moisture. This country, which belongs to monsoon territory, necessarily encounter one of this stress almost every year, even though the level is different. Therefore, the facilities for both drought and excess moisture are required, but actually it is not easy to complete for them. On this account, crops tolerant to drought, excess moisture and pests should be considered for establishing summer crops. For the districts damaged habitually every season, adequate crops should be cultured and appropriate method of planting, drainage and weed control should be applied diversely. Injuries by temperature is mainly attributed to lower temperature particularly in late fall and early spring, although higher temperature often causes some damages depending upon the kind of crops. Sometimes, lower temperature in summer season playa critical role for yield reduction in the summer crops. However, certain crops are prevented to some extent from this kind of stress by improving varieties tolerant to cold, hot weather or early maturing varieties. As is often the case, control of planting time or harvesting is able to be a good management for escaping the stress. Lodging, plant diseases and pests are considered as a direct or indirect damage due to weather stress, but these are characters able to be overcome by means of crop improvement and also controlled by other suitable methods. In addition, polytical supports capable of improving constitution of agriculture into modern industry is urgently required by programming of data for the damages, establishment of damage forecasting and compensation system.

• Research in Plant Disease
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• v.16 no.3
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• pp.238-246
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• 2010

In 2006 fall, a preliminary survey of viruses in two important medicinal plants, Cynanchum wilfordii and C. auriculatum, was conducted on the experimental fields at the Agricultural Research and Extension Services of Chungbuk province in Korea. On each experimental fields, percentage of virus infection was ranged from 20 to 80%, and especially an average of disease incidence propagated by roots was twice higher than that by seeds. The various symptoms were observed in Cynanchum spp. plants, such as mosaic, mottle, necrosis, yellowing, chlorotic spot and malformation etc. In electron microscopic examination of crude sap extracts, filamentous rod particles with 390-730 nm were observed in most samples. The virus particles were purified from the leaves of C. wilfordii with typical mosaic symptom, and the viral RNA was extracted from this sample containing 430-845 nm long filamentous rod. To identify the viruses, reverse transcription followed by PCR with random primers was carried out. The putative sequences of P3 and coat protein of potyvirus were obtained. From a BLAST of the two sequences, they showed 26-38% and 62-72% identities to potyviruses, respectively. In SDS-PAGE analysis, the subunit of coat protein was approximately 30.3 kDa, close to the coat protein of potyvirus. In bioassay with 21 species in 7 families, Chenopodium quinoa showed local lesion on inoculated leave and chlorotic spot on upper leave, but the others were not infected. RT-PCR detection using specific primer of C. wilfordii and C. auriculatum samples, all of 24 samples with virus symptom was positive, and five out of seven samples without virus symptom were also positive. On the basis of these data, the virus could be considered as a new member of potyvirus. We suggested that the name of the virus was Keunjorong mosaic virus (KjMV) after the common Korean name of C. wilfordii.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.171-182
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• 2018

Papaya (Carica papaya L.) is one of the crops widely planted in tropical and subtropical areas. The papaya fruit has low calories and are plentiful in vitamins A and C and in minerals. A major problem in papaya production is a plant disease caused by the papaya ringspot virus (PRSV). The first PRSV-resistant GM papaya expressing a PRSV coat protein gene was developed by USA scientists in 1992. The first commercial GM papaya cultivars derived from the event was approved by the US government in 1997. Development of transgenic papayas has been focused on vaccine production and limited agricultural traits, including insect and pathogen resistance, long shelf life, and aluminum and herbicide tolerance. Approximately 17 countries, including the USA and China, produced transgenic papayas and/or commercialized them, which provoked studies on biosafety assessment and development of GM-detection technologies. For the biosafety assessment of potential effects on human health, effects of long-term feeding to model animals have been studied in terms of toxicity and allergenicity. Studies on environmental safety assessment include influence on soil-microbial biodiversity and transfer to soil bacteria of GM selection markers. Many countries, such as Korea, the European Union, and Japan, that have strict regulations for GM crops have serious concerns about unintended introduction of GM cultivars and food commodities using unauthorized GM crops. Transgene- and/or GM event-specific molecular markers and technologies for genomics-based detection of unauthorized GM papaya have been developed and have resulted in the robust detection of GM papayas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.196-204
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• 2018

The main objective of this study was to identify the best quality rice for cultivation on reclaimed land in Jeollabukdo-Province based on yield, head rice ratio, protein content, amylose content, and Toyo taste value evaluations. Seven varieties of rice were grown for two years on the reclaimed land. The Sukwang variety had the earliest heading date. The tiller number for the Younghojinmi variety was 19 on average, and its variation in tiller number was the lowest, which showed that the safety for cultivation of the variety was high on the reclaimed land with respect to that of the other varieties. The culm and panicle lengths of the Sukwang and Hyunpum varieties were the highest at 81.8 and 21.3 cm, respectively. Shindongjin produced the highest thousand grain weight at 27.7 g, whereas Haepum produced the lowest at 22.3 g. The number of grains per panicle for 7 all varieties was statistically equal for both years. The yield order for the varieties was Shindongjin (590) > Hopum (575) > Younghojinmi (552) > Sukwang (551) > Hopum (543) > Mipum (534) > Haepum (498 kg/10a), which showed that there was no significant difference in average yield between the varieties when both years are taken into consideration. However, the annual difference in Haepum yield between 2015 and 2016 was the highest at 108 kg/10a, indicating low cultivation safety. The head rice ratio of Younghojinmi was higher than for the other cultivars in both 2015 and 2016. However, there was no significant difference between the 2 years when the averages for all varieties were analyzed. There was was a considerable difference in protein and amylose content between the varieties in the two years, although this was not apparent in the results when the average over 2 years for each variety was calculated. There was no significant difference between the two years with respect to the average head rice ratio, and the protein and amylose contents of the seven varieties. The Toyo taste values for the Sukwang and Mipum varieties were higher than for the other varieties. Based on the principle characteristics, such as Toyo value, the Sukwang variety is a suitable substitute for Shindongjin, which has been previously used to produce high-quality rice on the reclaimed land.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.326-335
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• 2007

This study was conducted to assess the environmental risks of anthracnose resistant transgenic chili peppers with the PepEST gene on non-target organisms in the agroecosystem environments during the chili pepper growing seasons in 2006. We quantitatively collected arthropods assemblages living on leaves and flowers of chili peppers on June 20, July 25, and August 25 by using an insect vacuum collector to compare the patterns of arthropod community structures between non-transgenic chili peppers (nTR, WT512) and anthracnose resistant transgenic chili peppers (TR, line 68). We found the seasonal difference with the highest species richness and Shannon's diversity in July's sampling among the growing seasons (P<0.05) and each sampling season showed the different arthropod community composition. We also found there was no statistical difference between the two types of crops, nTR and TR, at each sampling time (P>0.05). The significance level of arthropod community showed that there were lots of seasonal difference of functional groups as well as taxa but only the herbivore group in the functional groups was significantly different for the types of plants (P<0.05). So, we further examined the herbivore groups to find any potential damage and identified the possibility of herbivorous damage from some herbivores, grasshoppers, aphids and thrips. Although we couldn't find any adverse effects from the environmental risk assessment between the arthropod community structures on two types of plants from our results, we should keep working for the environmental risk assessment because of the herbivorous potential risk possibility.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.127-136
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• 1996

Mak-kimchi (shredded kimchi) which was prepared in a commercial factory was packed in bottle (200 g) under vacuum (560 mmHg) or atmosphere, and chemical characteristics and microbiological parameters were monitored during storage at 5, 15 and $25^{\circ}C$, respectively. Optimum ripening time of the kimchi at different temperature were 2 days at $25^{\circ}C$, 5 days at $15^{\circ}C$ and more than 60 days at $5^{\circ}C$. By vacuum treatment pH and acidity changes in kimchi were considerably retarded. The vacuum of each bottle released within 1 or 2 days at 25 or $15^{\circ}C$, respectively but the pack at $5^{\circ}C$ maintained more than 380 mmHg vacuum for 36 days and then the vacuum slowly released. The colour of kimchi (lightness, redness, yellowness) in bottle increased sharply at $25^{\circ}C$ and $15^{\circ}C$ but sustained a stable level with vacuum treatment at $5^{\circ}C$. The range of total viable count of kimchi in bottle was $10^7{\sim}10^{10}/ml$. The number decreased by storage temperature drop to $5^{\circ}C$ and even more vacuum treatment than atmosphere treatment at $5^{\circ}C$. Lactobacillus brevis, L. plantarum, L. acidophilus, Aerococcus viridans and Streptococcus faecium subsp. casseliflavus were identified in bottled kimchi and L. brevis and L. plantarum contributed to the main function during kimchi fermentation. Those main lactic acid bacteria decreased in numbers at $5^{\circ}C$ than 25 or $15^{\circ}C$ and even more declined in case of vacuum treatment.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.649-653
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• 2009

"Cheongan" is a new japonica rice variety developed from a cross between SR15225-B-22-1-2-1 and Iksan431 in summer season, 1997 by National Institute of Crop Science, RDA. The line SR15225-B-22-1-2-1 has good canopy architecture and multi-disease and insect resistance, and Iksan431 has translucent milled rice and good eating-quality. Heading date of Cheongan is August 13 in central lowland and mid-mountainous areas. "Cheongan" having culm length of 84 cm shows relatively semi-erect pubescent leaf blade and rigid culm, tolerance to lodging with and good canopy architecture. This variety has 14 tillers per hill and 126 spikelets per panicle. It shows tolerance to heading delay and spikelet sterility comparable to Hwaseongbyeo when exposed to cold stress. Leaf senescence of Cheongan progresses slowly during the ripening stage and the viviparous germination ratio was 59 %, similar to that of Hwaseongbyo. "Cheongan" shows moderately resistance to blast disease, but susceptible to stripe virus and brown planthopper. The milled rice of "Cheongan" exhibits translucent, clear non-glutinous endosperm and medium short grain. It shows similar amylose content of 18.7%, gelatinization temperature, and similar palatability of cooked rice compared to Hwaseongbyeo. The milled rice yield of this cultivar is about 5.54 MT/ha at ordinary season culture in local adaptability test for three years. Especially, "Cheongan" has better milling properties of higher 98.4% and 73.9% in the percentage of head rice in milled rice and milling recovery of head rice, respectively, than those of Hwaseongbyeo. "Cheongan" could be adaptable to the central and mid-southern plain area, and mid-western coastal area of Korea.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.532-537
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• 2011

'Seolgaeng' is a new Japonica rice variety developed from an 'Ilpumbyeo' mutant line, N-methyl-N-nitrosourea (MNU) treatment on fertilized egg cell, by a rice breeding team of National Crop Experiment Station, Rural Development Administration in 2001. This variety has about 134 days of growth duration from transplanting to harvesting in central plain area of Korea, a good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Seolgaeng' is more than that of 'Hwaseongbyeo'. The milled rice appearance of this cultivar is an opaque, but it has amylose content (19.3%) similar to 'Hwaseongbyeo'. It is superior to hypae formation of Aspergillus orzyae in the making of fermented rice and amount of pigmentation in fermented rice by Monascus anka that of 'Ilpumbyeo'. This variety showed slow leaf senescence and considerable resistance to viviparous germination. It is moderately resistant to leaf blast and susceptible to bacterial blight, virus disease and insect pests. The yield performance of this rice cultivar is about 5.27 MT/ha in milled rice in local adaptability test for three years from 1999 to 2001). 'Seolgaeng' is adaptable to central and southern plain areas of Korea.

• Journal of Practical Agriculture & Fisheries Research
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• v.21 no.1
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• pp.49-59
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• 2019

The field trial was performed to evaluate the rice growth and yield in different direct seeding methods after Italian Ryegrass Harvest The required time for seed emergence was for 7 ~ 8days in the tested direct seeding methods and there was high in seedling establishment in order of wet hill-seeding with iron-coated seeds > water seeding with iron-coated seeds > wet hill-seeding with soil coverage with pregerminated seeds. The rice plant height was shorter in the tested direct seeding methods than that of machine transplanting until 45day after seeding but there was not significant difference in terms of statistical analysis at 63day after seeding. The growth of tiller number in the rice plant was high in water seeding with iron-coated seeds and wet hill-seeding with soil coverage and low in wet hill-seeding with iron-coated seeds compared to machine transplanting. The yield component in the tested direct seeding methods was not significant difference in terms of statistical analysis. The milled rice yield in the tested direct seeding methods was higher 2 ~ 8% being with 4.94 ~ 5.24t/ha than that of machine transplanting but there was not significant difference in terms of statistical analysis. The percentage of head rice was low in the tested direct seeding methods compared to machine transplanting. The weedy rice was not occurred in the tested rice cultivation methods. In conclusion the direct seeding method would be recommended to be a suitable to in following by Italian ryegrass harvesting in southern area of Korea in terms of reduction in production cost and high income basis for rice growing farmers.