• 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.

• Journal of Korean Society of Forest Science
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• v.79 no.4
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• pp.431-434
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• 1990

The growth pattern of bud-shoot-needle of isolated 15-year-old trees, and seansonal changes in litter-falls and fine root dry weights in the unthinned 28-year-old plantation were investigated to understand the growth phenology of Pinus koraiensis. Shoot growth was continued by 7th June when buds appeared, while current needle growth was by 19th July when the bud growth started. Most of the litter-falls occurred in October but many of them were fallen in July and August due to storms, Fine roots were produced mostly in autumn(1,004 kg/ha), and were dead during winter (583 kg/ha) and spring(1,331 kg/ha).

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.235-241
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• 2017

The purpose of this study was to investigate the enhanced physiological activities of two Pichia strains, yeasts isolated from grapes pericarp. Based on phylogenetic analysis using 18S rRNA sequencing, two isolates were identified as Pichia manshurica GU-3 and Pichia terricola GU-4, respectively. The scanning electron microscopic analysis showed that the two isolates grown on YPD medium were of typical elliptical shape with buds and bud scars on cell surface. Physiological activities of the single and mixed Pichia cultures were monitored and compared. In mixed cultures after 72 h of incubation, the maximum activities of tyrosinase inhibition, ACE inhibition, and antioxidant were 81.7%, 45.9%, and 42.7%, respectively. Superoxide dismutase-like activity was approximately 30% in the mixed cultures. These studies demonstrate that Pichia species cultured in the form of mixture can enhance the physiological activities and has potential for the development of new bioactive products.

• Korean Journal of Medicinal Crop Science
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• v.18 no.2
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• pp.93-97
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• 2010

Cultural practices of Asparagus cochinchinensis in highland area were performed for a potential medicinal crop. These studies were examined to propagation methods, planting densities, nitrogen treatments, and cropping years. The results are summarized as follows. The adequate number of buds per tuberous root was 4 for vegetative propagation because the number of tuberous root harvested was 16.8 and the yield was also the highest, exhibiting 1,060 kg/10a. The suitable planting time for vegetative propagation was later than early April. If the earlier tuberous roots were planted, the less they emerged. The highest emergence rate was obtained from the planting density of $30{\times}20cm$ as 97.2% while the yield was highest in the $30{\times}15cm$ density, exhibiting 1,883 kg/10a with emergence rate at 94.9. It seemed that the higher planting density promoted plant height growth and yield in Asparagus cochinchinensis. The highest fresh weight was recorded at 6 kg/10a of nitrogen fertilizer into the sandy loam soil compared to the level of 0, 3, 9 kg/10a. The yield was increased with cropping years. However, the proper harvesting time was the second year of cultivation because the rate of weight increase was maximized in the 2-year-old tuberous root. The yield in the third year was decreased as compared to that of the second year.

• 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.

• Journal of Sericultural and Entomological Science
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• v.14 no.1
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• pp.1-7
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• 1972

Recently, young mulberry trees grown in the reclaimed hill land are frequently attacted by the die-bark and the buds of the trees developed poorly. In order to learn the cause of the injury mentioned above available boron content in the soils and the bark of young shoots have been analyzed. The results are as follow; Available boron content in the soil of the damaged mulberry fold was 0.3-0.20 ppm, against 0.39-49 ppm in that of healthy mulberry field, and boron in the bark of the damaged trees was 10.63-12.99 ppm, and 18.42-21.02 ppm in that of the healthy trees. The organic matter content and available boron content in soils showed a highly significant possitive correlation. The moisture content in percent in the soil of the damaged mulberry held was 11.16 and 14.22 in that of healthy mulberry field.

• 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.

• The Plant Pathology Journal
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• v.35 no.4
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• pp.372-380
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• 2019

Pseudomonas syringae pv. actinidiae (Psa) is by far the most important pathogen of kiwifruit. Sustainable expansion of the kiwifruit industry requires the use of Psa-tolerant or resistant genotypes for the breeding of tolerant cultivars. However, the resistance of most existing kiwifruit cultivars and wild genotypes is poorly understood, and suitable evaluation methods of Psa resistance in Actinidia have not been established. A unique in vitro method to evaluate Psa resistance has been developed with 18 selected Actinidia genotypes. The assay involved debarking and measuring the lesions of cane pieces inoculated with the bacterium in combination with the observation of symptoms such as callus formation, sprouting of buds, and the extent to which Psa invaded xylem. Relative Psa resistance or tolerance was divided into four categories. The division results were consistent with field observations. This is the first report of an in vitro assay capable of large-scale screening of Psa-resistance in Actinidia germplasm with high accuracy and reproducibility. The assay would considerably facilitate the breeding of Psa-resistant cultivars and provide a valuable reference and inspiration for the resistance evaluation of other plants to different pathogens.

• Korean Journal of Environmental Agriculture
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• v.38 no.2
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• pp.89-95
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• 2019

BACKGROUND: Liquid pig manure (LPM) has been used as an alternative for conventional fertilizers on some gramineous crops. However, its chemical properties varied widely depending on the degree of the digestion. A pot experiment was conducted to determine the responses of persimmon trees to immature (not well-digested) LPM application. METHODS AND RESULTS: Ten application levels of immature LPM, consisted of a total of 3 to 30 L in 3-L increment, were applied during summer to 5-year-old 'Fuyu' trees grown in 50-L pots. Increasing the LPM application rate caused defoliation, wilting, and chlorosis in leaves. When applied with the rate of 3 L during summer, the tree produced small fruits with low soluble solids and bore few flower buds the following season, indicating insufficient nutritional status. In trees applied with the LPM rates of 6~12 L, both fruit characteristics and above-ground growth of the trees appeared normal but some roots were injured. However, application of higher LPM rates than 27 L resulted in small size, poor coloration, or flesh softening of the fruits the current season. Furthermore, the high LPM rates caused severe cold injury in shoots during winter and weak shoot growth the following season. It was noted that the application of higher LPM rate than 9 L damaged the root, even though above-ground parts of the tree appeared to grow normally. CONCLUSION: The results indicated that an excessive immature LPM application could cause various injuries on leaves, fruits, and the roots in both the current and the following season.