• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.155-170
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• 2018

In this paper, mechanisms of gene editing technologies including ZFN, TALENS and CRISPR were briefly discussed with mutual advantages and disadvantages. Classification criteria of gene edited, site-directed mutagenesis (SDN) crops for regulatory purpose were also discussed. The number of studies using CRISPR technology was high and studies conducted on Arabidopsis thaliana and rice were highest, followed by tobacco, tomato, wheat, and corn. It has been applied to a variety of plants such as other grain crops, flower crops, vegetable crops, and fruit trees. The number of studies focused on practical application or commercialization in the future were also increasing yearly, and the scope of studies also expanded to include research on metabolic engineering for mass production of useful proteins or substances, development of disease resistant crops against viruses, bacteria, and fungi, abiotic environmental stressresistant crops, and increased yields. In addition to this, it was revealed that application range is becoming more diversified, including the development of parthenocarpic tomatoes, hybrid rice lines using male sterility and increased shattering resistance Brassica napus. It was also revealed that the number of CRISPR gene edited crops permitted by the USDA(APHIS) increases yearly, to be released in the international seed market soon.

• Korean Journal of Soil Science and Fertilizer
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• v.3 no.1
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• pp.11-16
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• 1970

In application of manganese and silica to Akiochi soil, growth of rice plant with potassium was remarkably increased, but the growth without potassium was stunted and the number of the tiller was relatively reduced in comparison with that receiving potassium. The minus potassium plant developed tiny brown spots on the leaves and color of the leaves was dark green. They had smaller leaves and shorter stem while heading advanced. Roots with potassium were long and thick, and new ones developed, while roots without K were very poor, the branch and hair roots very thin, and severe root rot was observed. With minus potassium treatment, the root rot of Jin Heung(commercial variety) was more severe than Nonglim 6(Akiochi resistant). Growth of plant without potassium was very poor, and potassium content of the plant was very low, while nitrogen, phosphorus, silica, iron and manganese contents were higher than potassium supplied plant. Application of $Mn+SiO_2$ to Akiochi soil lowered iron content of plant, and iron content of the plant were also reduced by application of potassium. From the results obtained it can be concluded that root damage of minus potassium plant grown in Akiochi soil supplied $Mn+SiO_2$ was caused by potassium deficiency. Potassium, and $Mn+SiO_2$ applications lowered iron content in the plant grown on Akiochi soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.5
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• pp.445-458
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• 1991

The literatures on meteorological disasters of which reported in Korea and abroad were reviewed and discussed in oilseed crops for refer to stable production and quality improvement of the crops. From the reviews, it was clarified that much of the reported disasters are almost same kinds as the other crops like reported in soybean and rice. However much of the disasters reported in oilseed crops were unconfirmed on their injury mechanisms or damage rate on yield loss and quality deteriorate comparing to the reports on soybean or rice. Among the meteorological disasters reported in oilseed crops, the disaters on sesame and groundnut were the most frequent in the numbers of report and water-flooding damage, drought damage, lodging damage in the kinds of disasters. Such kinds of the above disasters were leading to 90% yield loss in the most serious situation. To reduce the damage of meteorological disasters, it was suggested that the variety improvement of which highly resistant, and vinyl-mulching culture would be also an way to reduce water -logging and drought damage in sesame and groundnut in cultural practice. Further, it was indicated that the emphasis must be put on the oilseed crops to investigate and clarify the damage mechanisms, and reducing method of meteorological disasters in breeding and cultural practice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.63-68
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• 1975

Several high protein mutant lines(M4 plant generation, 1974) obtained from X-ray irradiated Jinheung variety were examined at three different locations for their agronomic characters, protein and grain yields. On the other hand, high protein-short culmed-early maturity mutant line No. 398 (M$_{10}$ plant generation, 1974) induced from Hokwang was crossed back to its mother to investigate the gene(s) controlling protein and its pleiotropic relation to other mutated characters. Although variation of protein percent of mutant lines from Jinheung was comparatively large depending on year and location, most of the high protein mutant lines had higher protein yield per unit area than the mother variety and their grain yields were equal to or better than the mother, being resistant to both leaf and neck blast. They were several days earlier-maturing and had shorter-culm except one mutant line. The culm length and heading date of F$_1$ between high protein mutant 398 and its mother Hokwang were intermediate. Accurate assessment of segregation of culm length and heading date in F$_2$ generation and protein percent in F$_3$ seeds will be conducted in 1975.

• Korean journal of applied entomology
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• v.20 no.3 s.48
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• pp.173-175
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• 1981

New screening method of varietal resistance by isotope $^{32}P$ was examined in these experiments. Insects were fed for 24 hrs. in the vials, with rice seedlings absorbed the solution if $0.6\~7{\mu}\;Ci\;^{32}P$ for 24 to 48 hrs. Feeding amounts of 3 species of plant-hoppers at the different stages and duration of infestation were investigated for effective process of screening method of the varietal resistance using isotope $^{32}P$. Feeding amount of $^{32}P$ of brown plant-hopper was observed for the different varieties. The results may be summarized as follows: 1. Brown planthopper fed greatest and the feeding amount were increased in order of white-backed planthopper and small brown planthopper. Female hoppers fed more than male. 2. Feeding amount was increased in order of adult, 5th instar, adult, 4th instar, 3rd instar 2nd instar and 1st instar. The duration of $24\~48\;hours$ is considered sufficient for insect infestation. 3. New screening method by $^{32}P$ was compared with seedling bulk screening method in view of feeding amount and plant reaction. Feeding amount of $^{32}P$ by brown planthopper in Milyang 47, resistant variety to this insect, was very low, while in TN 1, susceptible variety, it was very high about one hundred tines of Milyang 47.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.474-478
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• 2008

A new covered barley variety, "Geungangbori" was developed from the cross between Milyang 55 which have lodging tolerance and easy brittleness and Suweon 260 with good quality by barley breeding team in the Yeongnam Agricultural Research Institute (YARI) in 2002. A promising line, YMB3855-3B-14-1-1-1, was selected in 1999. It was designated as the name of Milyang 110. It was prominent and had good result from regional adaptation yield trials (RAT) for three years from 2000 to 2002 and released as the name of "Geungangbori". Geungangbori is resistant to barley yellow mosaic virus and moderately resistant to powdery mildow. The average maturing date was same with Olbori on paddy field in regional adaptation yield trials for 2000-2002. Its culm length is 17 cm shorter than that of Olbori and the spike length is 4.4cm, it's longer than olbori. The 1,000 grain weight of Geungangbori was 34 g, same as Olbori, but the number of spikes per $m^2$ and test weight ware lower than those of Olbori. The yield potential of Geungangbori was 4.22 MT/ha on paddy in regional adaptation yield trials for 2000-2002. which was 7% higher than that of Olbori. The cooking quality of Geungangbori were similar to Olbori such as water absorption rate and expansion rate. But the crude protein content is lower than Olbori. This variety is suitable for double cropping system with rice in the southern part of the Korean Peninsula.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.14
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• pp.1-40
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• 1973

There is a general tendency to increase nitrogen level in rice production to insure an increased yield. On the other hand, percentage of ripened grains is getting decreased with such an increased fertilizer level. Decreasing of the percentage is one of the important yield limiting factors. Especially the newly developed rice variety, 'Tongil' is characterized by a relatively low percentage of ripened grains as compared with the other leading varieties. Therefore, these studies were aimed to finding out of some measures for the improvement of ripening in rice. The studies had been carried out in the field and in the phytotron during the period of three years from 1970 to 1972 at the Crop Experiment Station in Suwon. The results obtained from the experiments could be summarized as follows: 1. The spikelet of Tongil was longer in length, more narrow in width, thinner in thickness, smaller in the volume of grains and lighter in grain weight than those of Jinheung. The specific gravity of grain was closely correlated with grain weight and the relationship with thickness, width and length was getting smaller in Jinheung. On the other hand, Tongil showed a different pattern from Jinheung. The relationship of the specific gravity with grain weight was the greatest and followed by that with the width, thickness and length, in order. 2. The distribution of grain weight selected by specific gravity was different from one variety to another. Most of grains of Jinheung were distributed over the specific gravity of 1.12 with its peak at 1.18, but many of grains of Tongil were distributed below 1.12 with its peak at 1.16. The brown/rough rice ratio was sharply declined below the specific gravity of 1.06 in Jinheung, but that of Tongil was not declined from the 1.20 to the 0.96. Accordingly, it seemed to be unfair to make the specific gravity criterion for ripened grains at 1.06 in the Tongil variety. 3. The increasing tendency of grain weight after flowering was different depending on varieties. Generally speaking, rice varieties originated from cold area showed a slow grain weight increase while Tongil was rapid except at lower temperature in late ripening stage. 4. In the late-tillered culms or weak culms, the number of spikelets was small and the percentage of ripened grains was low. Tongil produced more late-tillered culms and had a longer flowering duration especially at lower temperature, resulting in a lower percentage of ripened grains. 5. The leaf blade of Tongil was short, broad and errect, having light receiving status for photosynthesis was better. The photosynthetic activity of Tongil per unit leaf area was higher than that of Jinheung at higher temperature, but lower at lower temperature. 6. Tongil was highly resistant to lodging because of short culm length, and thick lower-internodes. Before flowering, Tongil had a relatively higher amount of sugars, phosphate, silicate, calcium, manganese and magnesium. 7. The number of spikelets of Tongil was much more than that of Jinheung. The negative correlation was observed between the number of spikelets and percentage of ripened grains in Jinheung, but no correlation was found in Tongil grown at higher temperature. Therefore, grain yield was increased with increased number of spikelets in Tongil. Anthesis was not occurred below 21$^{\circ}C$ in Tongil, so sterile spikelets were increased at lower temperature during flowering stage. 8. The root distribution of Jinheung was deeper than that of Tongil. The root activity of Tongil evaluated by $\alpha$-naphthylamine oxidation method, was higher than that of Jinheung at higher temperature, but lower at lower temperature. It is seemed to be related with discoloration of leaf blades. 9. Tongil had a better light receiving status for photosynthesis and a better productive structure with balance between photosynthesis and respiration, so it is seemed that tongil has more ideal plant type for getting of a higher grain yield as compared with Jinheung. 10. Solar radiation during the 10 days before to 30 days after flowering seemed enough for ripening in suwon, but the air temperature dropped down below 22$^{\circ}C$ beyond August 25. Therefore, it was believed that air temperature is one of ripening limiting factors in this case. 11. The optimum temperature for ripening in Jinheung was relatively lower than that of Tongil requriing more than $25^{\circ}C$. Air temperature below 21$^{\circ}C$ was one of limiting factors for ripening in Tongil. 12. It seemed that Jinheung has relatively high photosensitivity and moderate thermosensitivity, while Tongil has a low photosensitivity, high thermosensitivity and longer basic vegetative phase. 13. Under a condition of higher nitrogen application at late growing stage, the grain yield of Jinheung was increased with improvement of percentage of ripened grains, while grain yield of Tongil decreased due to decreasing the number of spikelets although photosynthetic activity after flowering was. increased. 14. The grain yield of Jinheung was decreased slightly in the late transplanting culture since its photosynthetic activity was relatively high at lower temperature, but that of Tonil was decreased due to its inactive photosynthetic activity at lower temperature. The highest yield of Tongil was obtained in the early transplanting culture. 15. Tongil was adapted to a higher fertilizer and dense transplanting, and the percentage of ripened grains was improved by shortening of the flowering duration with increased number of seedlings per hill. 16. The percentage of vigorous tillers was increased with a denser transplanting and increasing in number of seedlings per hill. 17. The possibility to improve percentage of ripened grains was shown with phosphate application at lower temperature. The above mentioned results are again summarized below. The Japonica type leading varieties should be flowered before August 20 to insure a satisfactory ripening of grains. Nitrogen applied should not be more than 7.5kg/10a as the basal-dressing and the remained nitrogen should be applied at the later growing stage to increase their photosynthetic activity. The morphological and physiological characteristics of Tongil, a semi-dwarf, Indica $\times$ Japonica hybrid variety, are very different from those of other leading rice varieties, requring changes in seed selection by specific gravity method, in milling and in the cultural practices. Considering the peculiar distribution of grains selected by the method and the brown/rough rice ratio, the specific gravity criterion for seed selection should be changed from the currently employed 1.06 to about 0.96 for Tongil. In milling process, it would be advisable to bear in mind the specific traits of Tongil grain appearance. Tongil is a variety with many weak tillers and under lower temperature condition flowering is delayed. Such characteristics result in inactivation of roots and leaf blades which affects substantially lowering of the percentage of ripened grains due to increased unfertilized spikelets. In addition, Tongil is adapted well to higher nitrogen application. Therefore, it would be recommended to transplant Tongil variety earlier in season under the condition of higer nitrogen, phosphate and silicate. A dense planting-space with three vigorous seedlings per hill should be practiced in this case. In order to manifest fully the capability of Tongil, several aspects such as the varietal improvement, culural practices and milling process should be more intensively considered in the future.he future.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.81-86
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• 2013

'Mogwoo', a new high yield and whole crop silage rice (Oryza sativa L.) cultivar, was developed by the rice breeding team of the National Institute of Crop Science, RDA, Suwon, Korea, from 1999 to 2009, and was released in 2010. It was derived in 1999 from a cross between Dasanbyeo, having a high yield, and Suweon431/IR71190-45-2-1. A promising line, SR25848-C99-1-2-1, selected by the pedigree breeding method, was designated the name of 'Suweon 519' in 2007. This cultivar has about 155 days of growth period from seeding to heading, and is tolerance to lodging, with erect pubescent leaves as well as a long and thick culm. This cultivar has the same number of tillers per hill and higher spikelet numbers per panicle compared to Nokyang. 'Mogwoo' has longer leaves compared with other Tongil-type varieties. This new variety is resistant to grain shattering, leaf blast, bacterial leaf blight, and small brown planthopper. The biomass yield of 'Mogwoo' was 1,956 kg/10a in a regional test over three years. The result shows that 'Mogwoo' is adaptable to central and south-east plain areas of Korea.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.111-131
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• 1975

The study has been carried out to investigate the occurrence, damage, characteristics of the pathogen, environmental conditions affecting the disease outbreak, varietal resistance, forecasting, and chemical control of bacterial leaf blight of rice in Korea since 1964. Bacterial leaf blight of rice became a major disease in Korea since 1960. A correlation was found between the annual increase of epidemics and increase of cultivation area of susceptible varieties, Jinheung, Keumnampung etc. Areal damage within the country showed that the more was at southern province, Jeonnam, Gyeongnam and western coast, and at flooded rice paddy. Yield reduction directly related with the amount of infection on upper leaves at heading stage. Fifty per cent of reduction resulted when the lesion area was more than 60 per cent. Less than 20 per cent of lesion area, however, was not affected so much on yield loss One hundred and six isolates collected from all over the country were classified as 8 strains by using 4 different bacteriophages in 1973. It was, however, only two in 1965. There were some specificities on varietal distributions among the strains such as that the Jinheung attacked mainly by strain A, B, C and I, those attack Kimmaze were A, B, H and I. Most strains were found from Tongil except D and E, whereas Akibare was only variety that attacked by strain E. Low temperature, high humidity, heavy rainfall and insutficient daylight favored the disease epidemics. Especially, typhoon and flooding at heading stage were critical factors. The earlier transplanting the more disease was resulted, and more nitrogen fertilizer application accerelated the diseased development in general. The resistance to the disease varied by growing stage of the sane plants. All of recommended varieties in Korea were susceptible to the disease except Norm No. 6 and Sirogane which moderately resistant. The pathogen, Xanthomonas oryzae, was detectable from extract of healthy seedlings that were grown in the field with an heavy infection previous year. The more bacteriophage in irigation water resulted the more disease outbreak, and the existence of more than 50 bacteriophages in 1ml. of irrigation water were necessary to initiate the disease out break. The curves representing occurrence of bacteriophages and disease outbreak were similar with 15 days interval. The survey of bacteriophage occurrence can be utilized in forecasting of the disease two weeks ahead of disease outbreak. Three applications of chemicals, Phenazin and Sangkel, in weekly intervals at the early satage of out-break depressed the symptom development, and increased yield by 20per cent. Proper period for the chemical application was just before the number of bacteriophage reaches 50 in 1ml. of irrigation water.

• Research in Plant Disease
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• v.13 no.3
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• pp.131-136
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• 2007

Occurrence of popcorn disease on mulberry fruits was surveyed in several locations in Korea from 2005 to 2007. The diseased fruits turned grayish white and changed to hard and black sclerotia during overwintering after falling onto the ground. Apothecia produced from overwintered sclerotia in the fields of mulberry trees were observed in early May. Two types of apothecia were produced from the sclerotia, which were cup-shaped or club-shaped. The fungus with cup-shaped apothecia was identified as Ciboria shiraiana, and that with club-shaped apothecia as Scleromitrula shiraiana. C. shiraiana occurred at the ratio of about 6 vs. 4 in the fields. Occurrence of the disease differed remarkably depending on years, locations, and varieties of mulberry trees investigated. Field survey of the disease incidence showed that Baekhahyeongsang, Dahojosaeng, Hasusang, a native variety and Sawonppong 22 were resistant to the disease, Cheongilppong, Daeseongppong, Guksang 20 and Turkey-D were moderately susceptible, and Cateneo, Moreji and Sanggwa were highly susceptible. Disease incidence in the fields mulched with nonwoven fabrics or plastic films was much lower than that in the non-mulched fields. Disease incidence in the fields mulched with rice straws was similar to that in the non-mulched fields.