• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.607-618
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• 2012

The blueberry gall midge, Dasineura oxycoccana (Diptera: Cecidomyiidae), has known as a key pest of blueberries in the southeastern United States, Europe and Canada. It can cause considerable damage to developing flower buds and also injure vegetative growth by distorting and blackening shoot tips on blueberries. In 2010, same damage symptoms were observed on blueberries, Vaccinium spp., in Hwaseong-si, Gyeonggi-do. And, D. oxycoccana was identified from the farms and it was designated as a quarantine pest in Korea. The occurrences of D. oxycoccana and its damages were investigated in the blueberry greenhouse in 2011. Nationwide survey revealed that most of the blueberry greenhouses were infected by D. oxycoccana. An environment-friendly management method for D. oxycoccana was developed by changing soil environment in the blueberry greenhouse.

• Journal of Ginseng Research
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• v.34 no.1
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• pp.23-29
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• 2010

This study examined the biological characteristics of the insect and examined potential cultural controls using peduncle topping methods. Ginseng stem fungus gnat eggs hatched after 5 days; ecdysis lasted 3-4 weeks, and after 5 days pupation, adults emerged. Adults deposited eggs 1-2 days after emerging, and the entire life cycle lasted 32-40 days. The fungus gnats laid eggs $327\times220{\mu}m$ in size on cut planes of stems, but not on intact stem parts that had not been topped or wounded. Analyses of major weather data for the experimental areas and weather data for the past 30 years acquired from the Korea Meteorological Administration revealed that fungus gnat dispersion was prevalent under highly humid conditions and in areas with thick and frequent fogging. Among the topping times examined, fungus gnat damage to ginseng was lowest when topping occurred in late May. Among the five different topping methods evaluated on experimental ginseng farms, the cumulative fungus gnat damage to ginseng was low (0.8%) under partial peduncle topping (removal of peduncle with lateral fruit remaining) and removal of only flower buds (0.6%), with fungus gnat control effects of 82% and 86%, respectively, compared to conventional topping (removal of peduncle about 5 cm above its base). No fungus gnat damage to ginseng was observed under the no-topping treatment. These results suggest that partial topping of peduncles, while letting lateral fruits remain, is a potentially environmentally friendly method of controlling the ginseng stem fungus gnat.

• Journal of Ginseng Research
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• v.37 no.2
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• pp.227-247
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• 2013

MicroRNAs (miRNAs) are a class of recently discovered non-coding small RNA molecules, on average approximately 21 nucleotides in length, which underlie numerous important biological roles in gene regulation in various organisms. The miRNA database (release 18) has 18,226 miRNAs, which have been deposited from different species. Although miRNAs have been identified and validated in many plant species, no studies have been reported on discovering miRNAs in Panax ginseng Meyer, which is a traditionally known medicinal plant in oriental medicine, also known as Korean ginseng. It has triterpene ginseng saponins called ginsenosides, which are responsible for its various pharmacological activities. Predicting conserved miRNAs by homology-based analysis with available expressed sequence tag (EST) sequences can be powerful, if the species lacks whole genome sequence information. In this study by using the EST based computational approach, 69 conserved miRNAs belonging to 44 miRNA families were identified in Korean ginseng. The digital gene expression patterns of predicted conserved miRNAs were analyzed by deep sequencing using small RNA sequences of flower buds, leaves, and lateral roots. We have found that many of the identified miRNAs showed tissue specific expressions. Using the insilico method, 346 potential targets were identified for the predicted 69 conserved miRNAs by searching the ginseng EST database, and the predicted targets were mainly involved in secondary metabolic processes, responses to biotic and abiotic stress, and transcription regulator activities, as well as a variety of other metabolic processes.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.371-374
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• 2010

The blossom midge, Contarinia maculipennis Felt (Diptera: Cecidomyiidae) originated in Southeast Asia and is present in Japan, the continental USA, and Hawaii. Recently, C. maculipennis was intercepted in Japan, USA and the Netherlands by using orchid flowers imported from Southeast Asian countries. This pest is designated as a quarantine pest in Korea because of its potential damages to vegetables and ornamental plants. In Korea, similar symptoms of damage, which mighty be caused by C. maculipennis, have been investigated in western orchids, especially on Dendrobium phalaenopsis, from Mid-2000s. Official recognition was given to C. maculipennis in 2007, followed by an investigation on the occurrences of C. maculipennis and its damages, mainly on D. phalaenopsis, in 2008~2009. We emphasize caution concerning the possibilities that C. maculipennis could infest flower buds of orchids and carry out management strategies for this pest in the future.

• Korean Journal of Medicinal Crop Science
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• v.23 no.2
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• pp.161-167
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• 2015

This study was carried out to determine the effects of light controls and leaf mold on root growth and physiological responses of Atractylodes japonica growing in forest farming. The experiment was performed by light controls (100%, 62.5%, 40.3% and 19.7% of full sunlight) and application of leaf mold to soil. Height, stem diameter, number of flower buds and root collar diameter were the highest in leaf mold within 62.5% of full sunlight (relative light intensity 62.5%). And these were the higher in leaf mold within each light level. As the shading level increased, light saturation point and maximum photosynthesis rate decreased. As the light level decreased, SPAD value increased in control and leaf mold. As a result of surveying the whole experiment, A. japonica was judged worse root growth under the lower light level. It was concluded that the light level was one of the most important factors to produce A. japonica. Also, producing high-quality of A. japonica with the price competitiveness by using leaf mold like the experiment can be an effective way to increase incomes for farmers.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.55-66
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• 2016

This study was carried out to investigate the effect of artificial light sources with different light qualities on the growth and flowering characteristics of a herbaceous long-day plant, Petunia ${\times}$ hybrida Hort. Seedlings of petunia cultivar 'Madness Rose' were potted, acclimated for one week, and grown in a phytotron equipped with tube- and bulb-type fluorescent lamps (FL tube and bulb), tube-type white light-emitting diodes (LED tube), halogen lamps (HL), metal halide lamps (MH), and high pressure sodium lamps (HPS) for 10 weeks. The temperature, photoperiod, and photosynthetic photon flux density (PPFD) in the phytotron were $22{\pm}2^{\circ}C$, 16 h, and $25{\pm}2{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. Light sources combined with HL promoted stem elongation, and plant height and internode length decreased with increasing red to far-red (R:FR) ratio. FL tube + LED tube, HPS, and FL tube promoted branching, whereas plants grown under light sources combined with HL did not have any branches. Days to flowering (from longest to shortest) occurred as follows: FL tube + HL > FL tube + HL > MH > HPS = FL tube + FL bulb > FL tube + LED tube > LED tube > FL tube, indicating that reducing the R:FR ratio of the light sources promoted flowering. Only 20% of plants grown under an FL tube flowered, whereas under all other treatments, 100% of plants flowered. At 10 weeks after treatment, plants grown under HPS and MH had (cumulatively) 12 open flowers, and those grown under FL tube + FL bulb, LED tube, FL tube + LED tube, and HPS treatment had approximately seven flower buds. These results suggest that light sources with low R:FR ratios promote flowering and stem elongation in petunia, but they reduce its ornamental value due to overgrowth and poor branching.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.83-90
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• 2002

Resistance to Phytophthora Capsici and horticultural characteristics of selections from the resistance sources such as PI123469, PI201234, PI201232, AC2258 (=Line 29), CM334, KC268, KC358, KC820, KC821, KC822, KC823 (Line 29), KC462, KC463, KC464 were evaluated and recorded in the process of seed increase. Selections of PI123469, PI201234, PI201232, AC2258, KC823 (Line 29 = AC2258) of them showed the highest level of resistance. A considerable difference in the level of resistance was observed between lines selected from the same sources. The variation between selections derived from the same source was thought to be attributable to natural cross-pollination that may have occurred during the seed increase. Therefore, securing self-pollinated seed by wrapping the flower buds before anthesis would be necessary to obtain genetically pore resistant lines. The next alternative would be to increase the seed in small net houses for single line or field cage.

• Korean Journal of Plant Taxonomy
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• v.35 no.1
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• pp.47-55
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• 2005

During the course of the field trip to Mt. Baekdu and Manchurian region especially along the border of North Korea, young flower buds were collected and fixed to analyze the meiotic configuration of chromosomes and to discuss the cytotaxonomic characteristics of these areas. A total of 29 taxa with 31 populations of vascular plants were analyzed chromosomally. Among them, 26 taxa with 28 populations were collected from Mt. Baekdu which include Papaver radicata var. pseudoradicata, Bupleurum euphorbioides, Oplopanax elatus, Silene jenisseensis, and Gentiana jamesii and three taxa collected from Manchurian region which include Scrophularia buergeriana, Ostericum grosseserratum and Callistephus chinensis. The first report of chromosome numbers were provided here for those species of Artemisia lagocephala as 2n = 9II, Cacalia komaroviana as 2n = 30II, Chrysanthemum zawadskii var. alpinum as 2n = 27II and Rodiola rosea as 2n = 11II,

• Plant Resources
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• v.7 no.1
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• pp.29-35
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• 2004

Root chicory (Cichorium intybus L. var. sativus) is potential alternative medicinal and sugar crop which accumulates a high amount of linear polyfructan, inulin in its roots. A problem in root production is that over-wintered stock plants often flower. Once the plant becomes reproductive, stem elongation and root growth slows and floral buds arise from every node, rendering the plants useless for propagation. The objectives of this research was to examine the effectiveness of manipulating environmental factors containing photoperiod, temperature and number of leaf states. The experiment was performed in growth chamber to create two photoperiods (8 h, and 16 h) with three temperature regimes (5$^{\circ}C$/3$^{\circ}C$, 1$0^{\circ}C$/8$^{\circ}C$ and 15$^{\circ}C$/13$^{\circ}C$ day/night temperature) for a total of six treatments on three type of true-leaf stage of plant. Data of bolting rate, shoot and root length, shoot and fresh weight was invetigated in each treatments. This is the first report on changes in bolting rate and shoots and roots production during a whole growing season and differences in the effect of cold and photoperiod treatment depending on the true-leaf stage of plant.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.543-546
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• 2009

Intermediate parent "Wonkyo Ga-Dangwagi 1" (Malus domestica Borkh.) was released from Fruit Research Division, National Institute of Horticultural & Herbal Science, Korea in 2008. It was derived from the cross between "Starkrimson" and columnar type "McIntosh Wijcik" in 1992 after selection tests from 2000 to 2008. Trees are moderately vigorous and have spreading branching habit. It bears abundant flower buds on one-year-old branches and fruits mainly on spurs or short branches. Harvesting time of this variety is late September, 7 days later than that of "Hongro" in Suwon. The fruit is conical to narrow conical in shape and bright red in skin color. Fruit size is small with weight of 200~240g on an average and fruits have $14^{\circ}Bx$ soluble solid and medium acidity. It is moderately susceptible to alternaria leaf spot (Alternaria alternata). "Wonkyo Ga-Dangwagi 1" is a promising apple cultivar and will appeal to young people with good sugar-acid balance.