• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.510-515
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• 2018

Hwangmichal, a yellow waxy corn hybrid, is a single cross hybrid developed in 2014. This hybrid was created by crossing the seed parent KY30 and pollen parent KY9. Hwangmichal has yellow kernels with a conico-cylindrical ear shape. The days to silking of Hwangmichal were similar to that of Ilmichal, a check hybrid. The ear height ratio of Hwangmichal was 50%, which was lower than that of Ilmichal, and its number of tillers was less than that of Ilmichal. The ear size of Hwangmichal was smaller than that of Ilmichal and the kernel set ratio was 89%. Its sensory evaluation was better than that of Ilmichal. The carotenoid content of Hwangmichal was $32.2{\mu}g/g$, which was much higher than that of Ilmichal. Lodging resistance of Hwangmichal was better than that of Ilmichal. Although the number of fresh ears of Hwangmichal was more than that of Ilmichal, the weight of fresh ears was lower than that of Ilmichal. The flowering period of its parent lines was well matched and seed production was 3:1 at a planting density of parent lines of more than 2:1. It is adaptable to the whole country except for Jeju-do. The plant variety protection right of Hwangmichal was registered in June 2017, and its grant number is 6728.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.172-177
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• 2011

This study was conducted to establish the optimal condition for in vitro propagation of wild Cynanchum wilfordii. The highest in vitro seed germination rate of 91.6% was obtained from the seed treated with gibberellic acid ($GA_{3}$) (100 ppm) for 24 hours followed by cultured on Woody Plant Medium (WPM) media supplemented with 1.0 mg/L 6-benzyl adenine (BA). The best shoot height obtained (5.2 cm) in medium with 1.0 mg/L $GA_{3}$, but the plants was grown abnormally and eventually died. The highest number (2.4) was shown when shoot were in cultured on the media including 0.1 mg/L BA after 4 weeks. Root induction from shoot obtained in vitro culture was effective on ventilation and without plant growth regulators (PGRs) and root length was highly developed (2 cm) at 0.1 mg/L naphthalene acetic acid (NAA). The highest survival rate (70%) was when plantlet grew pre-ventilation of in vitro condition.

• Korean Journal of Optics and Photonics
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• v.32 no.3
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• pp.120-125
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• 2021

We have developed a linearly polarized high-power Yb-doped fiber laser in the master oscillator power amplifier (MOPA) scheme for efficient spectral beam combining. We modulated the phase of the seed laser by pseudo-random binary sequence (PRBS), with the bit length optimized to suppress stimulated Brillouin scattering (SBS), and subsequently amplified seed power in a 3-stage amplifier system. We have constructed by coiling the polarization-maintaining (PM) Yb-doped fiber, with core and cladding diameters of 20 ㎛ and 400 ㎛ respectively, to a diameter of 9-12 cm for suppression of the mode instability (MI). Finally, we obtained an output power of 1.004 kW with a slope efficiency of 83.7% in the main amplification stage. The beam quality factor M² and the polarization extinction ratio (PER) were measured to be 1.12 and 21.5 dB respectively. Furthermore, the peak-intensity difference between the Rayleigh signal and SBS signal was observed to be 2.36 dB in the backward spectra, indicating that SBS is successfully suppressed. In addition, it can be expected that the MI does not occur because not only there is no decrease in slope efficiency, but also the beam quality for each amplified output is maintained.

• Journal of Life Science
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• v.32 no.2
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• pp.155-160
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• 2022

Kenaf (Hibiscus cannabinus L.), one of the four major fiber crops, is attracting attention for its efficient CO₂-absorbing ability and versatility for producing daily supplies, including textiles. In Korea, a new cultivar 'Jangdae' was established in 2013. The ease of cultivation and seed gathering of 'Jangdae' has led to its nationwide cultivation. However, evaluation of the bioactivities of the different parts of kenaf, and especially the 'Jangdae' cultivar, remains rudimentary. In this study, the antithrombosis and antioxidant activities of extracts prepared from different parts of the 'Jangdae' cultivar were evaluated by determining their effects on blood clot formation. Extracts prepared from seeds (HC-SD), seedpods (HC-SP), leaves (HC-L), stems (HC-S), and roots (HC-R) of the 'Jangdae' cultivar strongly inhibited blood clot formation. In particular, the HC-SD, HC-SP, and HC-S extracts showed strong inhibition against the coagulation factors prothrombin, and thrombin. The HC-SP extract showed strong antioxidant activities, such as scavenging ability against DPPH anion, ABTS cation, nitrite, and reducing power. Since blood clot formation is closely related to oxidative stress, the HC-SP extract could be developed as a novel anticoagulation and antioxidant resource. This is the first report of the antithrombosis activities of different parts of H. cannabinus L. cv. 'Jangdae'.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.249-254
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• 2022

Silkworms, which have for long been used as an insect resource for industrialization, have recently attracted attention as potential bio-factories for the production of novel biomaterials. In this regard, material production is typically achieved based on transformation technology, mediated via microinjection, in which a target gene is inserted into eggs containing an embryo. However, an essential step in the microinjection procedure is egg fixation, which can be a time-consuming and laborious task. Therefore, in this study, using the 3DCADian program, we adopted a 3D printing approach to model egg liners and glue drawers, which can contribute to facilitating egg alignment and fixation, thereby enhancing transformation efficiency by reducing time consumption and fatigue. After rendering using Fusion 360, the two supplementary tools were produced by printing with nylon resin (PA12) and Sinterit Lisa Pro. Subsequent analysis of the time required to fix eggs on glass slides using the two manufactured tools, revealed that the processing time was reduced by approximately 18.6% when the two tools were used compared with when these tools were not used. These innovations not only reduced fatigue but also contributed to more effective use of the microscope and manipulator for microinjection. Consequently, we believe that with additional research and refinement, the egg liner and glue drawer developed in this study could be used to enhance silkworm transformation efficiency and study similar transformation systems in other industrial insects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.783-789
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• 1997

This study was conducted to identify leakage of fluorescent substances out of 56 crops and to develop sorting methods of nonviable seeds of Chinese cabbage. Fluorescent substances were detected from 36 species, Chinese cabbage, radish, broccoli, cauliflower, egg plant and rape seed etc. In Chinese cabbage, the germination rate of non-sorted seeds decreased rapidly with ageing of seeds at 45$^{\circ}C$ and 100％. After Chinese cabbage seeds soaked for 4hrs and coated with cellulose, the sorting ratio of non fluorescent seeds were decreased 91.3％ to 1.7％ by increasing ageing periods from control to 8 days, while fluorescent seeds were increased drastically from 8.7％ to 98.3％. Also, incubation of water soaked dead seeds of Chinese cabbage treated with 0.5-1.0％ ninhydrin and 0.01N sodium thiosulfate for 30~60 minutes at 35$^{\circ}C$ developed purple color.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.169-169
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• 2022

Over the past 100 years, the global average temperature has risen by 0.75 ℃. The Korean Peninsula has risen by 1.8 ℃, more than twice the global average. According to the RCP 8.5 scenario, the CO₂ concentration in 2100 will be 940 ppm, about twice as high as current. The National Institute of Crop Science(NICS) is using the SPAR (Soil-Plant Atmosphere Research) facility that can precisely control the environment, such as temperature, humidity, and CO₂. A Python-based colony photosynthesis algorithm has been developed, and the carbon and nitrogen absorption rate of rice is evaluated by setting climate change conditions. In this experiment, Oryza Sativa cv. Shindongjin were planted at the SPAR facility on June 10 and cultivated according to the standard cultivation method. The temperature and CO₂ settings are high temperature and high CO₂ (current temperature+4.7℃ temperature+4.7℃·CO₂ 800ppm), high temperature single condition (current temperature+4.7℃·CO₂ 400ppm) according to the RCP8.5 scenario, Current climate is set as (current temperature·CO₂400ppm). For colony photosynthesis measurement, a LI-820 CO₂ sensor was installed in each chamber for setting the CO₂ concentration and for measuring photosynthesis, respectively. The colony photosynthetic rate in the booting stage was greatest in a high temperature and CO₂ environment, and the higher the nitrogen fertilization level, the higher the colony photosynthetic rate tends to be. The amount of photosynthesis tended to decrease under high temperature. In the high temperature and high CO₂ environment, seed yields, the number of an ear, and 1000 seed weights tended to decrease compared to the current climate. The number of an ear also decreased under the high temperature. But yield tended to increase a little bit under the high temperature and high CO₂ condition than under the high temperature. In addition, In addition to this study, it seems necessary to comprehensively consider the relationship between colony photosynthetic ability, metabolite reaction, and rice yield according to climate change.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.104-115
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• 1992

The rice culture techniques included 'Jodosukyungbeob'(旱稻水耕法 : culture techniques of early-ripening paddy rice), 'Mandosukyungbeob' (晩稻水耕法) : culture techniques of late-Ripening paddy rice 'Handobeob'(旱稻＆lt;山稻＆gt;法 : culture techniques of upland rice), 'Myojongbeob'(苗種法 : culture techniques of paddy rice by transplanting), 'Kunangbeob'(乾秧法 : culture techniques of rice by transplanting which rears seeding in dry paddy) and 'Sudogunpanongbeob'(水稻乾播農法 : culture techniques of paddy rice seeding in dry field). Especially, 'Kunangbeob' and 'Sudogunpanongbeob' were originally developed in Korea as seen in 1600s(Kyoungje : 經濟) and early 1800s (Yoji : 要旨). In 'Jodosukyungbeob' it took 9 days for seed dipping, water-sprouting and prevent damage by birds, each for 3 days in China, but in Korea seed dipping in water took 3 days and the rest of the procedures were flexibly established. In matured soils, practices were fall plowing right after harvest, recognition of effective tillering and additional fertilization use of human manure, and stimulation of sprouting by lime application. The unique culture techniques adequate for Korean situations were practiced, which included weed control after draining accurately for 3 to 4 times, draining at mid season for improving wind and drought tolerance, rice harvesting at appropriate time for preventing grain shattering, and seeding in rows. 'Mandosukyungbeob' was improved techniques contrast to those of China, and the major contents were selection of proper varieties, good stand establishment by seeding high rates, induction of vigorous tillers, and adoption of 'Jokjongbeob'(足種法 : seeding method by foot). Also, one of the most prominent rice cultures by our ancestors was 'Kunpanongbeob' that was systemized form habitual practice of Pyongan Province. The unique technique actualized was 'Hando [旱稻(山稻)]' culture technique which was the combinations of 'Jokjongbeob', root stimulation method, and disaster-tolerant mixture cropping with adoptation of variety theory, although it was originated from China. The transplanting techniques has come before 'Jikseol'($\ulcorner$直說$\lrcorner$) and its merits were sufficiently realized. However, this method was basically prohibited from the early Chosun dynasty because extremely bad harvest was expected under drought conditions and insufficient conditions of water storage. But, it was permitted in the areas that contained water all the times and in case of large-scale farming especially. Most of rice culture was transplanted in the end of the Chosun dynasty because transplanting was continuously spreaded in the three southern provinces of Korea. Under these circumstances, transplanting technique was improved from the early to the end of the Chosun dynasty by weed control, fertilizing, water management, and quadratic transplanting. Based on these techniques, agricultural productivity was improved 5 times by that time. 'Kunpanongbeob' was created and developed properly for Korean conditions that is dry in early season and flooding in late season. This was successively developed and established into transplanting technique of nursery seedling.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.40-45
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• 2020

Over 500 genetically modified organisms (GMOs) have been developed since 1996, of which nearly 44% have glufosinate herbicide-tolerant traits. Identification of specific markers that can be used to identify herbicide-tolerant traits is challenging as the DNA sequences of the gene(s) of a trait are highly variable depending on the origin of the gene(s), plant species, and developers. To develop specific PCR marker(s) for the detection of the glufosinate-tolerance trait, DNA sequences of several pat or bar genes were compared and a diverse combination of PCR primer sets were examined using certified reference materials or transgenic plants. Based on both the qualitative and quantitative PCR tests, a primer set specific for pat and non-specific for bar was developed. Additionally, a set of markers that can detect both pat and bar was developed, and the quantitative PCR data indicated that the primer pairs were sensitive enough to detect 0.1% of the mixed seed content rate.

• Journal of Life Science
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• v.20 no.8
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• pp.1186-1192
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• 2010

Soybean [Glycine max(L.) Merr.] is an important crop, accounting for 48% of the world market in oil crops. Improvements in economic traits, such as quality and oil constituents, arethe most important objectives in soybean breeding. The objective of this study was to identify quantitative trait loci (QTLs) that control seed size and fatty acid contents in soybean. 115 $F_{2:10}$ recombinant inbred lines (RIL) developed from a cross of 'Keunolkong' and 'Iksan10' were used. Narrow-sense heritability estimates based on a plot mean on 100 seed weight, saturated fatty acid (palmitic acid + stearic acid), and oleic, linoleic, and linolenic acid content were 0.72, 0.60, 0.83, 0.77 and 0.81, respectively. The 100 seeds weight was related to seven QTLs located on chromosomes 1, 3, 8, 9, 16 and 17. Two independent QTLs for saturated fatty acid content were identified on chromosomes 17 and 19. Five independent QTLs for oleic acid content wereidentified on chromosomes7, 11, 14, 16 and 19. Five QTLs for linoleic acid content were located on chromosomes 2, 11, 14, 16 and 19. Three QTLs for linolenic acid content were located on chromosomes 8, 10 and 19. Oleic, linoleic, and linolenic acid had one major common QTL on chromosome 19. Thus, linoleic and linolenic acid content were identified as common QTLs.