• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.375-380
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• 2007

This study was conducted to develop herbicide-resistance domestic maize plants by introducing the CP4 5-enol-pyruvylshikimate-3-phosphate synthase (CP4 EPSPS) gene using Agrobacterium tumefaciens-mediated immature embryo transformation. Immature embryos of five genotypes (HW1, KL103, HW3, HW4, HW7) were co-cultivated with strains Agrobacterium tumefaciens (strain C58C1) containing the binary vector (pCAMBIA2300) carrying Ubiquitin promoter-CP4 EPSPS gene and Cauliflower mosaic virus 35S (CaMV35S) promoter-nptll gene conferring resistance to paromomycin as a selective agent. The presence and expression of CP4 EPSPS transgene were confirmed by PCR, RT-PCR and Northern blot analysis, respectively. Also, the resistance to glyphosate in the transgenic maize ($T_1$) was analyzed by shikimate accumulation assay. The frequency (%) of paromomycin-resistance callus was 0.37, 0.03, 2.20, 2.37, and 0.81% in pure lines HW1, KL103, HW3, HW4 and HW7, respectively. EPSP transgene sequences were amplified in putative transgenic plants that regenerated from paromomycin-resistance calli of two inbred lines (HW3, HW4). Of them, RT-PCR and Northern blot analyses revealed that the transgene was only expressed in two transgenic events (M266, M104) of HW4 inbred line, and a mild glyphosate resistance of transgenic event (M266) was confirmed by the lower shikimate accumulation in leaf segments. These results demonstrate that transgenic maize with herbicide-resistance traits in Korean genotype can be genetically obtained.

• Applied Microscopy
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• v.38 no.1
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• pp.21-28
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• 2008

Carnivorous plants vary in their unique features of morphology, ultrastructure and biochemical properties by species. Furthermore, prey-capturing mechanism as well as structural and physiological adaptations have been used for grouping various carnivorous species. In Drosera plants, glandular trichomes, which develop in the leaf epidermis, are known to play the most important role during the prey capturing process. The present study examined such trichomes, focusing on the glandular type, in leaves of Drosera anglica using scanning and transmission electron microscopy. Three types of rudimentary glandular trichomes were found to develop within the folded leaf primordia and immature leaf during early development. The first type, stalked glandular trichomes (Type I), occurred on the margin and upper epidermis of the leaf. With maturation, the longest glandular trichomes having lengthy stalks, ca. $2.2{\sim}5.1\;mm$, developed along the margin, while shorter stalked trichomes, ca. up to $200\;{\mu}m$, were found on the inner leaf blade. The shorter ones consisted of a globose head having two layers of secretory cells, parenchyma bell cells and tracheids and a multicellular stalk. The stalks gradually decreased in length in centripetal fashion. The second type, Type II, having ca. $15{\sim}30\;{\mu}m$ short stalks, also developed along the inner blade. Both types secreted mucilage from the secretory cells which had a thin cell wall and cuticle layer. The sessile six-celled glandular trichomes were the third type, Type III, and were $25{\sim}40\;{\mu}m$ in length. They were distributed most commonly throughout the upper and lower epidermis, petiole and even on the stalk surfaces of the first two types of trichomes. The third type was also found to be involved in the active secretion. In prey capturing leaves, all trichome types secreted substances through thin cuticles in the head cell wall, which exhibited relatively loose wall components.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.881-891
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• 2016

The susceptibility of the predatory mite, Neoseiulus californicus to extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures was evaluated in laboratory bioassays. In treatments with plant extracts tested, 76-86% of adult female predators survived after 7 days after treatment. Adult female predators treated with plant extracts tested produced 68.3-81.1% as many eggs as did control females and eclosion of eggs deposited by treated predators was not affected. Moreover, treatment of plant extracts tested showed no toxic effect on N. californicus eggs and produced 100% hatchability. Survival of N. californicus nymphs was not seriously affected by exposure to the plant extracts tested. Immatures of N. californicus survived on the leaf disc treated with plant extracts tested and 78-90% of immature predators reached adulthood. These results suggest that extracts of Melia azedarach, Piper nigrum, Syringa velutina and their mixtures expected to be promising candidates for use in integrated mite management program with N. californicus.

• Journal of Life Science
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• v.31 no.6
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• pp.581-586
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• 2021

The high fatality of COVID-19 (Corona Virus Disease 2019) is closely related to acute pneumonia and severe blood clot formation in brain, heart, kidney and lung. The use of low-molecular weight heparins has been shown to reduce the risk of thrombosis and reduce fatality rates among COVID-19 patients. In this study, we investigated the antithrombotic activity of different parts of C. sativa extracts to determine its potential in preventing blood clots in patients with thromboprophylaxis. The extracts of leaf, stem, root, immature flower and seed of C. sativa showed strong inhibitory activities on blood clot formation. In particular, the flower extract showed the strongest inhibitions against blood coagulation factors and thrombin. Strong hemolysis activities were observed in flower extract and seed extract, suggested that removal of the hemolysis active compounds in th extracts is necessary. This is a first report of anti-thrombosis activities of different parts of C. sativa extracts, and our results suggest that C. sativa extract has potential has a valuable bioresource for high-value products.

• Journal of Plant Biotechnology
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• v.50
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• pp.11-18
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• 2023

Manihot esculenta Crantz, commonly known as cassava, is a staple aliment that is a significant source of revenue for farmers. The embryogenic callus is crucial in the genetic engineering of various crop species, including cassava. Four cultivar cassava landraces from East Java were assessed for their ability to produce friable embryogenic callus (FEC) for protoplast isolation. In this study, four cassava cultivars; (Kaspro, Kuning, Gajah, and Gendruwo); were used to obtain FEC, which involved the culture of immature leaf lobes (ILLs) and apical buds (ABs) media containing MS supplemented with 33 μM picloram and 2 μM of CuSO₄ (M1) or MS supplemented with 50 μM 2,4-D and 2 μM CuSO₄ (M2). The highest FEC induction efficiency ranged from 72% to 57%, and the highest FEC number ranged from 4.7 to 3.7 with AB explants in media containing MS + 33 μM pilocram and 2 μM CuSO₄ (M1). On the other hand, the efficiency of somatic embryogenesis induction ranged from 67% to 53%, and the number ranged from 4.4 to 3.4. The efficiencies of FEC induction ranged from 48% to 42%, and the number ranged from 3.1 to 2.6 with AB explants in media containing MS + 50 μM 2,4-D and 2 μM CuSO₄ (M2); the efficiency of FEC induction ranged from 56% to 50%, and the value ranged from 3.6 to 2.4 with ILL explants. The FEC induction of the Gendruwo cultivar, which was examined using AB and ILL explants, demonstrated the lowest efficiency. Nevertheless, all four cultivars showed the ability to generate FEC, even though their effectiveness differed depending on the explant genotype and the applied media.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.237-248
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• 2008

Development of T. urticae was studied on the leaves of eggplant grown in hydroponics with nitrogen contents of 5 mM, 10 mM, 30 mM, and 60 mM. As the nitrogen level in hydroponics increased, it also increased in the plant whereas that of K, Ca, and Mg decreased. More nitrogen in hydroponics resulted in increased contents of water and crude protein, and decreased ash, carbohydrates, and fibers within the plant. Biomass was the heaviest as 989.5 g at 10 mM and the lightest at 60 mM. Leaf thickness and the content of chlorophyll increased as the content of nitrogen increased. Laboratory leaf disc tests obtained from plants grown at various nitrogen levels revealed that feeding and oviposition preferences of T. urticae were high at 30 mM and low at 5 mM. Ratio of damaged leaf by naturally occurring T. urticae on eggplants of 99 days post-transplant in the greenhouse was the highest as 98% at 60 mM. Degrees of damage on eggplants with and without T. urticae infestation turned up more as the differences in the levels of nitrogen in the hydroponics get bigger. No definite differences in the rate of T. urticae development was found between nitrogen treatment levels but, mortalities in immature stages dropped as the nitrogen levels went up. Adult longevity was the longest of 11.9 for female and 6.9 days for male at 60 mM. Oviposition period was also the longest as 11.7 days at 60 mM and shortened as the level of nitrogen decreased. The number of eggs oviposited was the most as 144.4 at 60 mM while it was the least as 41.0 at 5 mM. Sex ratio was 0.75 in favor of female at 10 mM. $R_o$ and T increased, no trends were detected in $r_m\;and\;{\lambda}$, while Dt decreased as the levels of nitrogen went up.

• Korean journal of applied entomology
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• v.47 no.3
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• pp.217-226
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• 2008

Development of T. urticae was studied on the leaves of eggplant grown in hydroponics with potash contents of 0 mM, 2 mM, 6 mM, and 12 mM. As the levels of potash increased, that of nitrogen decreased and that of P, K, Mg increased in the plant. While contents of crude protein and fiber decreased, those of ash and sugar increased. Carbohydrate content was the highest at 2 mM. Water contents increased as those of potash increased with the exception at 0 mM. Biomass was the heaviest as 552.7 g at 6 mM and the lightest at 0 mM. Leaf thickness and the content of chlorophyll increased as the content of potash increased. Laboratory leaf disc tests provided with various potash levels revealed that feeding and oviposition preferences of T. urticae were high at 6 mM and 12 mM, respectively. Ratio of damaged leaf by naturally occurring T. urticae on eggplants of 99 days post-transplant in the greenhouse was the highest at 6 mM. Development of immature stages of T. urticae shortened as the levels of potash increased with a less tendancy in male than in female. No differences were detected in adult longevity and oviposition period but the number of eggs laid was the most as 84.7 at 6 mM and the least as 40.6 at 0 mM. There were no differences in the rate of egg hatch and the ratio of sex. $R_o,\;r_m,\;and\;{\lambda}$ were the highest at 6 mM and the lowest at 0 mM. T and Dt were the lowest at 6 mM and the highest at 0 mM. There was a descending trand of T. urticae developmet when levels of potash either gets high or low in the hydroponics.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.78-85
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• 1996

The effects of growth regulators, sucrose and gelling agents were investigated to increase the efficiency of the callus growth and plant regenerarion in tissue culture of Angelica koreana Max. The fresh weight and dry weight of subcultured callus was highest in MS medium supplemented with 1 mg/l 2,4-D. Callus growth was excellent in 2% sucrose, but it was inhibited in propotion to sucrose content. Effect of gelling agents on callus growth was highest on 1.2% agar and 0.4% Gelrite medium, respectively. The browning of callus was protected on the media supplemented with 10 mg/l ABA and 5 or 10 mg/l $AgNO_3$. In the callus induction and growth from the peduncle of immature inflorescence, 2,4-D was more effective than NAA, and the frequency of callus induction was highest as 81.7% in 2 mg/l 2,4-D. Plant was not regenerated from the callus derived from young leaf. Somatic embryos were developed from the surface of callus drived from the peduncle of immature inflorescence in the medium containing 0.5 mg/l 2,4-D, 1 mg/l kinetin, 5 mg/l ABA and 5 mg/l $AgNO_3$. Plants were developed from the matured somatic embryos in the medium supplemented with 0.2 mg/l 2,4-D and 1 mg/l kinetin.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.353-358
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• 2008

The bean pyralid, Omiodes indicatus (Fabricius), moulted 4 times during larval period. When temperature increased from 15 to 20, 25, and $30^{\circ}C$, the developmental period of immature stages was shortened; 18.2, 7.5, 5.0, and 4.1 days of egg period; 51.8, 20.0, 12.7, and 9.9 days of larval period; 29.5, 12.0, 8.0, and 5.9 days of pupal period, respectively. Adult longevity was 16.0, 14.7, 11.2, and 7.5 days at respective temperatures. A female adult layed 57.0, 63.3, 82.2, and 31.7 eggs in 3.7, 6.0, 5.8, and 3.0 days of oviposition period at the same temperature regimes, respectively. Field survey in 2006 and 2007 showed that leaf damage on paddy field and upland soybeans began to appear in mid July, reaching its peaks in mid August and late September. Adults of the bean pyralid appeared in mid July and peaked in late August and early October.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.552-560
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• 2010

$GA_{4+7}$+BA, a plant growth regulator for induction of feathering in young apple tree and increasing fruit size, was applied by various methods on 'Gala'/M.9 apple trees in high density orchard for 4 years to investigate its effect on fruit and shoot growth. $GA_{4+7}$+BA($80-300mg{\cdot}L^{-1}$) increased fruit length, fruit weight, and L/D ratio regardless of application methods, but it did not affect soluble solid content, acidity, leaf area, and chlorophyll. Seed number was not affected by $GA_{4+7}$+BA application, however, more immature seeds was observed in treated 'Gala' fruit. Shoot growth was increased when spraying $GA_{4+7}$+BA at tree crown but not affected when spraying at fruit directly. More significant fruit growth was observed when $GA_{4+7}$+BA was applied on the fruits between late of May and early of June when fruit cell division ended; however, high concentration of $GA_{4+7}$+BA resulted in lower fruit storability because of lower firmness. Hence, more attention should be paid when applying high concentration of $GA_{4+7}$+BA to small sized fruit cultivars like 'Gala'.