• Journal of Animal Reproduction and Biotechnology
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• v.35 no.2
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• pp.171-176
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• 2020

Advancing the estrous cycle of mares is an essential breeding strategy that is routinely conducted by Thoroughbred breeders to improve economic outcomes. For this purpose, Equilume light masks have been developed as an alternative to existing technologies such as artificial lighting or hormonal treatments because they are considered as valid as existing methods with additional animal welfare advantages. For example, with the Equilume light masks, horses can be let out into the pasture, whereas they have to be kept indoors during lighting treatment. Because the function of Equilume light mask on the estrous cycle of mares is influenced by environmental factors such as nutrition condition and temperature, Equilume light mask should be studied in various environments. The objective of the present study was thus to verify the effect of Equilume light masks on the onset of the estrous cycle in Thoroughbred mares in South Korea. Mares were randomly selected and separated into two groups at two Thoroughbred horse breeding farms. The mares in the treatment group were equipped with Equilume light masks from November 18 to February 10 the following year. The body condition, the number and size (> 35 mm) of uterine follicles, and the uterine horn score of the mares were assessed on January 6 and February 10. The body condition scores were not different between the two groups. The treatment with the Equilume light mask had no positive effects on developing follicles and the reproductive tract. In conclusion, the use of Equilume light masks did not influence the seasonal resumption of the estrus cycles in Thoroughbred mares in South Korea.

• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.178-182
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• 2007

Rauvolfia serpentina (L.) Benth. ex Kurz is a medicinal plant and an endangered tropical rainforest plant species. Since the field cultivation that aims to fulfill the industrial needs is never accomplished, tissue culture appears to be the most feasible way to improve the quality and quantity of R. serpentina. This experiment used two kinds of explants (roots and shoots) to induce optimal root formation in different combinations of auxin and photoperiod. Each explants exhibited different responses on given treatments. Differentiated root could be produced from explants cultured in IBA 20 mg/L with and without light. The highest number of roots, root length and root weight induced from shoot explants were effective on MS medium containing IBA 20 mg/L and incubated under dark condition, while highest total weight (callus and root) from root explants cultured on MS medium supplemented 10 mg/L IBA and 10 mg/L NAA and incubated under day length (11/13 hr). The root induced from shoot explants produced the highest major alkaloid content. The highest content of ajmaline (2.17 ppm fresh weight) and reserpine (1.30 ppm fresh weight) were observed in shoot explants cultured in MS medium containing combination of IBA 10 mg/L and NAA 10 mg/L and incubated under dark condition, yohimbine (1.47 ppm fresh weight) was in the shoot explants cultured in MS medium containing NAA 20 mg/L and incubated under day length, while serpentine was absent.

• International Journal of Industrial Entomology and Biomaterials
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• v.47 no.1
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• pp.44-50
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• 2023

The Daehwangjam has excellent marketability and quality. However, precise silkworm breeding data on the recent high-temperature environment is not enough collected, and it is necessary to check whether stable Daewhangjam silkworm egg production was possible in poor environments. In this study, the timing of metamorphosis of the Daewhangjam parents Jam323 and Jam324 silkworms, in an optimal condition and a general condition similar to breeding grounds, was investigated to confirm that appropriate mating was achieved. Surprisingly, a number of female moths were discarded due to the metamorphosis of Jam324 female moths much earlier than Jam323 male moths in either an optimal or a general condition. To improve this, during the Jam324 female pupation period, the mild low-temperature of 15℃ was treated for the pupation period to delay the metamorphosis into female moths. Depending on the treatment period, the metamorphosis of the female pupa was delayed by more than 4 days, allowing normal mating with the Jam323 male moth. The eye pigments in a pupa also slowly accumulated in these treatments. In order to discover the side effects of low-temperature treatments, the voltinism of the Daewhangjam eggs was investigated, but most of them remained univoltine. Taken together, the low-temperature treatment during the female pupation period made it possible to use Jam324 female moths that were should be discarded, which means that stable and efficient management of Daewhangjam egg production is possible.

• Journal of Ecology and Environment
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• v.46 no.3
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• pp.243-249
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• 2022

Background: Mixed breeding herb Viola collina Besser, which produces both chasmogamous and cleistogamous flower, has limited habitats under closed canopy and short and early flowering timing, making it relatively more vulnerable to climate change. To better understand the effect of light and nutrient on the flower formation and vegetative growth of V. collina, a mesocosm experiment was conducted. Two-by-two factorial treatments of two light conditions (100% and 60% of natural light) and two fertilizer treatment conditions (fertilized and not fertilized) were applied in the mesocosm experiment. Results: The number of flowers, including chamogamous and cleistogamous flowers, was highest (5.65/pot) under 60% light and fertilized condition and lowest (1.41/pot) under 100% light and not-fertilized condition. However, above ground vegetative growth was highest (2.89 g/pot) under 100% light and fertilized condition and lowest (2.38 g/pot) under 60% light and not-fertilized condition. Above ground biomass to belowground biomass ratio was highest (1.50) under 60% light and fertilized condition and lowest (1.26) under 100% light and fertilized condition. Conclusions: This study showed that high light and nutrient are responsible for the vegetative growth, though the effect of fertilizer was reduced due to allocation and retainment of nutrients. In addition, the low light is necessary to make flowers, especially chasmogamous flowers.

• Journal of Korean Society of Forest Science
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• v.88 no.3
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• pp.379-388
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• 1999

As a first step for delineating the provenance regions of the forest trees in Korea, horizontal zones have been deduced primarily from the various climatic factors such as annual mean temperature, extremely low temperature, relative humidity, annual gum of possible growing days, duration of sunshine and dry index. The basic concept to the delineation of the provenance regions was based on the ecological regions, which was likely to be more practical than that on the basis of the typical provenance regions at the species level. Primary classification of the regions has been based on the forest zones(sub-tropical, warm-temperate, mid-temperate and cool-temperate) as a broad geographic region. Further classification has been carried out using cluster analyses among the basic regions within forest zone. On the basis of clustering, a total of 19 regions including 3 from sub-tropical, 6 from warm-temperate, 8 from mid-temperate and 2 from cool-temperate was horizontally delineated. Of the mean values of 6 climate factors at the broad geographic region level, three factors such as annual mean temperature, extremely low temperature, annual growing days showed directional tendencies from subtropical to cool-temperate, while the others didn't. The values of relative humidity, duration of sunshine and dry index varied among the provenance regions within forest zone. These three factors might he more sensitive by the micro-environment condition than by the macro-environment condition. Present study aimed to delineate the primary provenance regions for tentative application to forest practices. These will be stepwise revised through the supplement using accumulated information regard to genecological data.

• Journal of Animal Science and Technology
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• v.53 no.2
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• pp.99-106
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• 2011

This study estimated the genetic parameters of growth-related traits from 11-month-old olive flounder (Paralichthys olivaceus) base population in which wild and cultured broodstocks were introduced. The heritability of body weight, total length, body height, body shape, and condition factor of the base population was estimated to be 0.754, 0.753, 0.789, 0.438, and 0.369, respectively. Genetic correlations between body weight and total length, between body weight and body height, and between total length and body height were 0.969, 0.960, and 0.960, respectively, showing highly positive correlation. Genetic correlations between body weight and body shape, between total length and body shape, between body height and body shape were -0.403, -0.344, and -0593, respectively, showing low negative correlation. Overall, olive flounder might be an appropriate selective breeding species with the high heritability of the traits in an 11-month-old population.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.124-127
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• 2008

A new orange-colored, cut flower gerbera (Gerbera hybrida Hort.) cultivar 'Sweety' was developed from a cross between 'Grandeur' and 'Songsongee', followed by selections of seedlings and lines at the Flower Breeding Research Institute, Gyeongnam Agricultural Research and Extension Services (ARES) from 1999 to 2004. Three time evaluations were conducted from 2003 for the detailed characteristics of the new cultivar. 'Sweety' has semi-double type mini- or medium-sized flowers in good harmony with orange(RHS, 38-A) ray florets and a green center. It has good, stable flower shape and strong peduncle, and its vase life was 10.4 days. The average flower yield was about 51.0 stems per plant/year in greenhouse trails during 2003 and 2004. This cultivar was registered to the Korea Seed and Variety Service for commercialization in 2006. Year-round production of this cultivar is possible in the greenhouse condition in Korean climate.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.196-200
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• 2008

A new spary chrysanthemum (Dendranthema grandiflorum) cultivar 'Pinky' was bred from a cross between 'Rima' and 'Yen'. Progenies were investigated from 2004 to 2006 under shading culture in spring and retarding culture in autumn and the promising line was selected based on the performance of year-round production, white rust resistance and vase life. Pinky flowered around 20 October, and year-round production was possible by shading and lighting. Its flower was 3.1 cm in diameter, and had 38.4 petals and 26.8 flowers per stem in autumn. Its petal was narrow (0.4 cm) and pink with green in color at the flower center. Days to flower from short-day start for 'Pinky' was about 47 in spring. 'Pinky' showed a vase life of 20.9 days in autumn. This cultivar was commercially registered in 2007. 'Pinky' would be suitable for culture under the greenhouse and rain shelter condition in Korea.

• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.159-163
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• 2008

A New spary chrysanthemum (Dendranthema grandiflorum) cultivar 'Water Fog' was bred by open pollination of 'Angaesoguk'. Its characteristics were investigated three times from 2004 to 2006 under forcing culture in spring and retarding culture in autumn. The natural flowering time of 'Water Fog' was 24 October, but year-round production was possible by shading and lighting. It had flower diameter of 2.3 cm, 46.5 petals and 34.4 flowers per stem in autumn. The petal was narrow(0.4cm) and the color of petal was white with presence of green at flower center. Days to flower from short-day start for 'Water Fog' was about 48 in spring. 'Water Fog' showed the vase life of 22.6 days in autumn. This cultivar was registered for a commercialization in 2007. 'Water Fog' would be cultured under greenhouse and rain shelter condition in Korea.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.138-146
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• 2011

This study was carried out to select salt tolerant zoysiagrass breeding lines. Eighty two native zoysiagrasses collected from S. Korea were used in this study. Saline water were prepared by mixing sea water and tap water. ECw levels of saline water treated ranged from 2 to $3dS{\cdot}m^{-1}$. Zoysiagrass planted in pot by sprigging were soaked into the plastic box containing saline water. Winter injury was investigated under the pot condition. Most of Z. japonica types did not show winter injury. But Z. tenuifolia type, Z. matrella type, and Z. sinica type showed winter injury under the pot condition at Cheonan area. NaCl level in soil was increased from 0% to 0.51% by treatment of saline water. Soil ECe measurement showed upto $170dS{\cdot}m^{-1}$. Z. tenuifolia type (Z5034), Z. matrella type ('Konhee', Z4109, 'Semill'), Z. japonica type (Z1055, Z1040, Z1008, 'Zenith', 'Millock') and medium leaf type zoysiagrass (Z6096, Z6118, Z6021, Z6074) resulted in below 30% leaf firing under the saline condition. This approach might be useful for selecting salt tolerant breeding lines.