• Horticultural Science & Technology
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• v.17 no.3
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• pp.355-360
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• 1999

This study was carried out to investigate the effect of irrigation frequency, particle size and depth of perlite medium on the growth of Dendranthema grandiflorum (Ramat.) Kitamura 'Shuhouno-chikara' grown on recycling system. In Exp 1, the irrigation frequency (IF) was designed as 3 (IF3), 9 (IF9), and 18 (IF18) times a day. Fine and coarse particle size (PS) of perlite was used as a media, and depth of media (DM) was 15 and 10 cm contained in $34{\times}120{\times}15cm$ styrofoam bed. In Exp 2, the IF was 3 (IF3), 6 (IF6), and 9 (IF9) times a day with the same amount of nutrient solution. Fine and coarse PS were used, and DM was 15 and 7.5 cm. In this study, high IF and fine PS was favorable for plant growth. However, as the IF became frequent, difference of plant growth between fine and coarse PS became smaller. Also, shallow media showed little difference with deep media in plant growth. Thus, decreasing the amount of media was recommended to reduce the production cost.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.292-297
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• 2015

A new cultivar of Hibiscus 'Red Bohanjae' (Hibiscus syriacus 'Red Bohanjae') was developed after crossing between Hibiscus syriacus 'Andong' (♀) with white flowers and Hibiscus syriacus 'Samchully' (♂) with pink flowers to improve flower quality and growth habit. The Hibiscus breeding program was initiated in 2002, and H. syriacus 'Red Bohanjae' was preliminarily selected as '02-RV-17' in 2003 due to its stable flower quality with rich pink flowers and small tree type. The selected line was further evaluated for growth characteristics, leaf shape, leaf size, flowering characteristics, and tested for distinctness, homogeneity, and stability during 2004-2007. The characteristics preserved by grafting. 'Red Bohanjae' showed a small growth habit with slightly upright branches. The tree had potential use as a potted plant or bonsai because of its dwarf form. The new cultivar 'Red Bohanjae' had violet-pink color flowers (RHS N78C) with red eye spots, small size (9.2 cm) and spatulate (I-type) petals. Leaves were 4.2 cm long and 2.3 cm wide. After the evaluation of plant characteristics for 3 years (2005-2007), it was registered as cultivar 'Red Bohanjae' (4118, plant variety protection rights number) in 2012. 'Red Bohanjae' having violet-pink flowers with red eye and dwarf tree form seems to be suitable for pot or bonsai cultivation in both indoor and outdoor conditions.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.298-301
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• 2015

A new Hibiscus syriacus variety, 'Dasom', was developed by radiation breeding using gamma ray exposure at the Korea Atomic Energy Research Institute (KAERI). Seeds of the original variety, 'Hongsun', were collected in 1993. These seeds were irradiated at 100 Gy dose and $M_1$ seeds were planted in a field of the KAERI in 1994. Lines with preferred flower color that were going to be used for street trees were initially selected in 1998. Analyses of characteristics were conducted from 2005 to 2010. The 5-year-old 'Dasom' plants were approximately 106 cm in height and averaged 19 branches, and thus were suitable for street trees. The flowers of 'Dasom' were semi-double type with medium red color and red eye spots. Petal length and width were about 4.0 cm and 3.3 cm, respectively. Flower diameter was slightly small, at about 5.8 cm, because of highly overlapping petals. The flowering period of 'Dasom' was about 105 days, which was 6 days shorter than that of the original variety, 'Hongsun'. However, the main charactersistics of 'Dasom' including leaf shape were similar to those of the original variety, 'Hongsun'.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.407-412
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• 2011

The germination of the buds in 'Hongisul' grapes is poor and especially the high ratio of shoots where the flowers failed to emerge it was difficult to secure a sufficient amount of harvest. Thus, in this study, the necrosis and the periodical change in the buds were observed morphologically and also the cause of necrosis of the bud was investigated in order to understand what was causing the low germination and flowering. There was no change in the size of the bud after June and based upon external observation, there wasn't any retrogression or withering. However, based on a microscopic examination, the ratio of whole bud and main bud necrosis of the 'Hongisul' grapes continued to increase after August, and specially the ratio of the main bud necrosis continued to increase up to October. As for the size of the buds on the shoots, the buds located on the $1^{st}-3^{rd}$ nodes from the basal part were small whereas the buds located on the $4-10^{th}$ nodes were comparatively larger in its size. The ratio of necrosis of the bud was the highest at the $1^{st}$ and $2^{nd}$ bud, meaning that the buds located at the basal part of the shoot were defective compared to those located at the end of the shoot. It was also found that when the growth of the shoot is active and the shoot diameter is thick, it hindered the development of the buds. Therefore, it was judged that long pruning of 'Hongisul' grapes would help the emergence of the flowers as you could use the buds that have comparatively developed better.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.499-509
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• 2017

Recently, there has been increased attention to the development of new plant cultivars with enhanced resistance to biotic and abiotic stress. To develop ginseng cultivars with such traits, systematic breeding programs and comprehensive field studies are prerequisites. In this study, we applied a pure-line selection method to identify a ginseng cultivar with enhanced stress resistance. Phenotypic and agronomic characteristics, seed yield, and physiological responses to biotic and abiotic stresses were investigated according to the guidelines of the International Union for the Protection of New Varieties of Plants (UPOV). In the newly developed 'Kowon' cultivar, the time of emergence, flowering, and berry maturity were intermediate between those of the controls, 'Yunpoong' and 'Chunpoong'. The stem length of 'Kowon' was intermediate, whereas the root length was shorter and the main root diameter was greater than those of 'Chunpoong'. In local adaptability tests conducted in three regions, the yield of 'Kowon' was $666kg{\cdot}10a^{-1}$; 27% and 4% higher than that of 'Chunpoong' and 'Yunpoong'. Diseases such as Alternaria blight, Phytophthora blight, mulberry mealybug, and nematode infestation did not occur in 'Kowon'; and it also exhibited moderate resistance to damping-off and anthracnose. In these cases, yellow spots occurred on aerial parts and the rusty skin of the root, and it exhibited moderate resistance at high temperatures. Our study demonstrates that 'Kowon', which has a high root weight and enhanced biotic/abiotic stress resistance, is a superior cultivar that could increase farmers' income.

• Journal of Life Science
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• v.26 no.3
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• pp.289-295
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• 2016

Sorbus commixta, a flowering plant in the Rosaceae family, is native to Japan and Ulleung Island, Korea. This plant is also called maga-mok or mai-mok in Korea because the bud of the stem has a similar shape to the teeth of a horse. In this study, hot water extracts from different parts of S. commixta, such as leaf, stem, and immature and mature fruits, were prepared, and their antithrombosis and antioxidant activities were evaluated. The extraction yield and pH of stem extracts were 3.99% and 5.5, respectively. The stem extracts contained 89.2 mg/g of total polyphenols and 28.3 mg/g of total flavonoids. The hot water extracts prepared from the leaf, stem, immature, and mature fruit of S. commixta exhibited no hemolytic activity against human red blood cells, up to a concentration of 0.5 mg/ml. In an anticoagulation assay, the stem extracts showed strong extension in thrombin, prothrombin, and activated partial thromboplastin times, whereas the other extracts had no anticoagulation activity. In a platelet aggregation inhibitory activity assay, all the extracts tested had no inhibitory activity against human platelets. With regard to antioxidation activity, the stem extracts showed stronger radical scavenging activity and reducing power activity than the other extracts. The calculated RC₅₀s, the concentration required for 50% radical scavenging activity, for DPPH anions, ABTS cations, and nitrite of the crude stem extracts were 119.7, 53.3, and 117.5 μg/ml, respectively, whereas they were 13.7, 5.2, and 14.9 μg/ml for DPPH anions, ABTS cations, and nitrite, respectively, for vitamin C. The results suggest that the stem extracts of S. commixta have strong potential for use as a novel resource for antithrombosis agents.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.437-442
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• 2004

Forage legumes are being used as an important source of protein for dairy farm as well as nitrogen fertilizer. This experiment was conducted to evaluate forage production and quality of five legumes at Cheonan Yonam College Experimental Livestock Farm for 1 year(2001-2002). Five legumes were crimson clover (Trifolium incarnatum L.) 'Tibbee', hairy vetch(Vicia villosa Roth) 'Common', red clover(Trifolium pratense L.) 'Kenland', persian clover(Trifolium resupinatum L.) 'Leeton', alfalfa(Medicago sativa L.) 'Vernal'. All legumes were shown cold hardiness of 8 rating or higher except crimson clover(7 rating). Flowering stage was observed 23th of April for crimson clover, 13th of May for hairy vetch, 3rd of May for red clover, and 12th of May for alfalfa. But persian clover didn't at harvest. Dry rnatter(DM) of crimson clover(17.6%) was the highest among legumes. In DM and total digestible nutrients(TDN) yields, crimson clover and hairy vetch were higher than those of other legumes. The crude protein of hairy vetch(20.5%) was the highest among legumes. In neutral detergent fiber(NDF) and acid detergent fiber(ADF), persian clover was the lowest(35.0% and 25.0%). Calculations of relative feed value(RFV) based on NDF and ADF of legumes were over 125(Prime degree) except hairy vetch. RFV and TDN of persian clover were the highest among legumes. According to the results of this study, crimson clover and hairy vetch are excellent in forage yield. Persian clover is superior in forage quality among legumes.

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.13-18
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• 2013

This study was conducted to examine the effect of temperature and relative humidity (RH) that might affect the pollen germination rate and pollen tube length in oriental melon. The experiment was performed using three cultivars namely 'Mallijangseong', 'Ohbokggul', and 'Joeundae' wherein environmental conditions were controlled by three different temperatures $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$ and also three RH levels 30%, 60%, and 90%. Based on the results in terms of temperature, true to all cultivars, plants exposed to $25^{\circ}C$ had the highest pollen germination rate while plants exposed to $15^{\circ}C$ had the lowest. Among the three cultivars, 'Mallijangseong' had the highest in terms of pollen germination rate, followed by 'Ohbokggul', and lastly was 'Joeundae' that showed the lowest germination rate. In the case of pollen tube length, pollen exposed under $35^{\circ}C$ showed the longest tube length, followed by pollen under $25^{\circ}C$, and pollen under $15^{\circ}C$ remarkably had the shortest tube length. Across the three cultivars 'Ohbokggul' had the longest pollen tube length. In the case of RH, pollen germination response among three cultivars depends on the humidity conditions but based on the results, there was no significant differences although high germination rate was observed in highest humidity condition. Between each cultivar, 'Ohbokggul' had the lowest pollen germination rate compared with 'Mallijangseong' and 'Joeundae' after exposure to different RH conditions wherein pollen germination showed significant differences among treatments. The pollen collected under 60% RH had the longest pollen tube length, followed by 30%, and the shortest was under 90% RH. In general, 'Ohbokggul' had the longest pollen tube length while 'Joeundae' had the shortest among the three cultivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.241-246
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• 2002

Rye-hairy vetch mixture would be recommended fur produce higher yield and conserving soil environment. This experiment was conducted to investigate the effect of planting and harvest dates on quality and productivity of rye-hairy vetch mixture. Plant height of rye and hairy vetch was increased with delayed harvest dates, but it found that there was on significant difference among seeding dates. The dry matter(DM) content was increased with delayed harvest dates, and it showed 30% DM in mid-May. Crude protein(CP) content was decreased sharply from 17~18% in heading stage to 9~10% in flowering stage. The content of ADF(Acid detergent fiber) and NDF(Neutral detergent fiber) were increased with delayed harvest date, but IVDMD(In vitro dry matter digestibility) and TDN(Total digestible nutrient) were decreased. The change of dry matter yield was affected significantly by harvest date but was not by seeding time. The results of this experiments indicated that harvest in late-April would be recommended to produce the highest yield and quality if it is considered to cultivate com fur silage. Harvest in mid-May would be recommendable with the cultivation of early maturity silage corn or sorghum $\times$ sudangrass hybrids.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.106-110
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• 1985

This trial was carried out to find out the optimum ridge and seeding rate for the seed production of Festuca arundinacea S. (variety Alta). It was composed of three ridge level (12, 18 and 24cm) and four seeding rates (10, 15, 20 and 25kg/ha) in a split-plot design with 4 replications. The experiment lasted from September 1979 to October 1981. 1. The beginning of heading state was May 12 and the date of full flowering stage was June 2. The optimum stage for the seed harvesting of Festuca arundinacea was about 43 days after beginning of heading stage. 2. The number of panicles were 157 per square meter from the best treatment 18cm ridge with 15kg seed/ha. And the 1000 grain weight was 2.79g for the treatment 12cm ridge with 10kg seed/ha. 3. The average seed yield for two years was 681kg/ha and the largest 831kg/ha for the treatment 18cm ridge with 25kg seed/ha. 4. the average germination rate of the harvested seed was 90.7 percent, and it showed a little higher germination rate from the lower level of seeding rate. 5. The average total DM production with two cuttings of aftermath was about 6715kg/ha. According to the increasing seeding rate and narrowing the ridge, DM yield was higher.