Young-Guk Kim

Study on Flowering, Bearing Fruit, Seed Harvesting and Seedling Transplanting Cultivation of Valeriana fauriei Briquet

This study was carried out to know the characteristics of flowering and bearing fruit, the optimum period, regions and methods for seed harvesting, the optimum temperatures for seed storage and germination, and the optimum period for sowing at nursery bed and seedling transplanting of Valeriana fauriei Briquet. The flowering and bearing fruit of Valeriana fauriei was developed from the before-year root. Optimum period for seed harvest of Valeriana fauriei was from late July to middle August, and optimum areas were the high elevated areas over 500 m above the sea level as Jinbu-myeon, Pyeongchang-gun, Gangwon-do. Using of net-bag for seed harvesting was the effective method to gather the full ripe seed, and bagging of net-bag was necessary from the season of middle May that was the flowering middle-stage. Germination rates don`t show the difference among the different temperatures of storage as approximately 41% at , or of seed storage temperatures. The optimum temperature range was in for seed germination at nursery bed. The optimum period for seed sowing at nursery bed was the late February, and the optimum period for seedling transplanting was the middle April.

Comparison of Artemisinin Content and Antioxidant Activity from Various Organs of Artemisia Species

One objective of this study was to compare the antioxidant activity from various organs of Artemisia species and identify new organs of Artemisia species with antioxidant activity. The various organs of the Artemisia species were analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays, which are widely used for evaluating antioxidant activity. A. annua, A. montana, A. stolonifera and A. gmelinii found to have strong antioxidant activity. These findings reinforce the potential of plants as valuable antioxidant sources. A second objective of this study was to compare the artemisinin content from various organs of Artemisia species and identify that a new organ of Artemisia species with high artemisinin content. Artemisinin is one of the most important phytochemicals found in the Artemisia species, and has been used for the treatment of malaria all over the world. Using high-performance liquid chromatography, we analyzed the artemisinin content from various organs of the Artemisia species. The roots of A. absinthium and A. rubripes howed high contents of artemisinin. This, roots of A. absinthium and A. rubripes are suggested as alternatives to A. annua as medicinal sources of artemisinin.

Variation of Bolting at Cultivation of Different Regions and Molecular Characterization of FLC homologs in Angelica gigas Nakai

This study were carried out to find bolting response of cultivation in different regions and to isolate FLC (FLOWERING LOCUS C) homologs in Angelica gigas Nakai. The mean temperature of different regions, ordering in altitude, were as follows: 100 m > 350 m > 530 m > 700 m. The largest amount of rainfall was occurred in the region of 350 m while the longest time of sunshine was occurred in the region of 100 m. The content of soil chemical properties in regions showed pH 6.2 ~ 7.4, T-N 0.17 ~ 26, organic mater , , exchangeable potassium and calcium and magnesium were 0.78 ~ 1.15, 3.9 ~ 10.0, . L5 line of A. gigas was occurred in bolting at all regions, but the bolting ratio was 60.0% in 700 m region with non-mulching treatment. Manchu of A. gigas was not occurred in bolting at all regions. The accumulation bolting ratio of L5 line by non-mulching was higher than that of mulching as 90.4% and 72.8% in 100 m region. The MADS-box transcription factor FLC is one of the well-known examples as a strong floral repressor. We decided to isolate FLC homologs from A. gigas as a starting point of flowering mechanism research of this plant. We have isolated two RT-PCR products which showed very high amino acid sequence homology to Arabidopsis FLC.

Effect of organic fertilizer application on growth characteristics and saponin content in Codonopsis lanceolata

Organic fertilizers were applied in four different forms: mixed organic matter, fermentation cake, bacterial culture, and rice husks, excluding conventional chemical fertilizer and non-treatment used as control. The results showed that soil pH was acidified after fermentation cake and chemical fertilizer treatment. Specifically, chemical fertilizer treatment showed higher phosphoric-acid content than other treatments, while total N content was higher in fermentation cake, mixed organic matter and chemical fertilizer. Growth of Codonopsis lanceolata showed superior tendency in the treatment of mixed organic matter and fermentation cake. Lancemacides, the major saponin of C. lanceolata, could be identified as foetidissimoside A, lancemaside A, lancemaside B, and lancemaside D. However, among them, quantitative analysis could not be conducted on foetidissimoside A due to its very low content, and lancemaside A was the most abundant saponin in the root from all the treatments. The content of lancemaisde A according to organic fertilizer application showed the highest value of 0.12xa0mgxa0g−1 in the treatment of mixed organic matter, followed by the fermentation cake, bacterial culture, non-treatment, rice husks and chemical fertilizer, in that order. The content of lancemaside B and D was very low compared to lancemaside A, and there was no difference among treatments. Therefore, it was verified that the growth of C. lanceolata was superior in application of mixed organic matter and fermentation cake, and the major saponin, lancemaside A, was also increased.

First report of powdery mildew caused by Podosphaera sp. on Cynanchum auriculatum

Powdery mildew symptoms were observed on the upper surface of leaves of Cynanchum auriculatum in Eumseong, Korea in October 2015. Microscopic observations and molecular characteristics determined this fungus as Podosphaera sp., which is reported for the first time on Cynanchum auriculatum.