• Korean Journal of Plant Taxonomy
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• v.41 no.2
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• pp.144-155
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• 2011

The infraspecific taxa of Adonis amurensis Regel et Radde are currently known to include one subspecies (subsp. nanus Y. Lee), two varieties (var. ramosa Makino, and var. dissectipetalis Y. Lee) and two forms (for. argentatus Y. Lee, and for. viridescensicalyx Y. Lee). Among them, the remaining three taxa except for subsp. nanus and var. dissectipetalis are unified with A. amurensis. Therefore, we examined the morphological characteristics and geographical distribution of A. amurensis in effort to elucidate the taxonomic status of subsp. nanus and var. dissectipetalis. After the subsp. nanus samples had been transplanted from their type locality, i.e. highland at more than 1,000 m above sea level, to a lowland habitat, we measured the samples' morphological characteristics. The range of values we recorded of the plant height and floral diameter from the subsp. nanus samples were within the parameters used to characterize A. amurensis. Accordingly, subsp. nanus has been characterized as an ecophene of A. amurensis. It is considered as a synonym of A. amurensis. Among the populations of A. amurensis (sensu Y.Lee, author), those with highly dissected petals at their apices have previously been described as var. dissectipetalis. However, this characteristic has been observed together with obtuse or rounded petal apices not only in one population but also in a single individual. However, populations with these characteristics belong to A. pseudoamurensis due to the simultaneous development of leaves and flowers, branched stems, acute leaf apices, and petals that are shorter than sepals. Therefore, we suggest that A. amurensis var. dissectipetalis be unified with A. pseudoamurensis. Very useful characteristics for distinguishing A. amurensis from its relative species are anthesis, the presence or absence of branches, the development of scales into normal leaves, the relative length of the sepals and petals, and the position of the stipules. A. amurensis is geographically restricted to E. Asia, including E. Siberia, and especially on the Korean Peninsula, it is distributed throughout the northern provinces of Gyeonggi province and in Gangwon province, Gyeongbuk province (Mt. Bohyeon-san) and Jeonbuk province (Mt Jeoksang-san) along Baekdudaegan mountain.

• Korean Journal of Poultry Science
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• v.39 no.3
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• pp.245-252
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• 2012

This study was carried out to investigate the performance of laying period of two-crossbred of Korean native chickens for producing laying hens. A total of four hundred eighty female 2-crossbred chicks that restored strains and were aboriginal at National Institute of Animal Science. There were four crossbreds (4 replications/crossbred, 30 birds/replication) as A) C strain ${\times}$ Y strain, B) C strain ${\times}$ L strain, C) C strain ${\times}$ G strain, and D) C strain ${\times}$ W strain, respectively. There were no significant difference on age at first egg among crossbreds (P>0.05). Egg weight and body weight of B crossbred at first egg was higher than other crossbreds (P<0.05). Body weight of B crossbred was the highest 20 to 72 weeks (P<0.05), and C and D crossbreds were lower compared to A and B crossbreds (P<0.05). Average feed intake of B crossbred was the highest among crossbreds (P<0.05), and that of A crossbred was higher compared to C and D crossbreds (P<0.05). Weekly feed intake of four crossbreds decreased from 50 weeks. Weekly egg weight of B crossbred was the highest and that of D crossbred was the lowest among crossbreds (P<0.05). Feed conversion ratio of A and B crossbreds was lower than that of C and D crossbreds. Hen-house egg production of C crossbred was the highest among crossbreds until 26 weeks old (P<0.05), but there was no significant difference among crossbreds from at the age of 26 weeks (P>0.05). Hen-day egg production decreased after at the age of 38 weeks. Weekly egg production of A and B crossbreds was higher compared to C and D crossbreds at the age of 68~72 weeks (P<0.05). These results suggested the basic data on the record of laying period of 2-crossbreed Korean Native Chickens for producing laying hens.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.15-24
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• 1992

The effects of CC the ovulatory response, oocyte normality, ovarian steroidogenesis and subsequent embryo developmental potential were examined in PMSG-treated rats. On Days of 25~27 of age, immature female Sprague Dawley rats were treated with three different doses(0.05, 0.1 or 1.0mg /day) of clomiphene citrate or vehicle. The females subsequently received 4IU PMSG on Day 28 and/or 10IU hCG on Day 30, and were killed on Day 31. Some females given 0.1mg CC or vehicle with 4IU PMSG were then mated and killed on Days 2, 3, 4 and 5 of pregnancy. Compared to vehicle(control) group, by increasing the doses of CC, there were a significant decrease in the ovulatory response as judged by both the proportion of rats ovulating and the mean number of oocytes per rat and a marked reduction of ovarian weight. The increasing doses of CC substantially promoted the degeneration(%) of oocytes ovulating in a dose-dependent manner. The CC-mediated inhibitions of the ovulatory response and ovarian weight were oompletely overcome by a subsequent treatment of hCG. Increasing doses of CC resulted in a siginificant elevation of serum estradiol with the decreased levels of progesterone and androgens. The additive treatment with hCG was effective to reduce the elevation of estradiol and to increase the reduction of progesterone produced by high dose(1.0mg) of CC. The preimplantation embryos recovered from 0.1mg CC-treated pregnant rats demonstrated a progressive early loss from Day 3 of pregnancy with a significant increase in the percentage of degeneration during all periods examined, compared to controls. The rate of progressive embryo cleavage in the CC-treated rats were slower than that in controls from Day 3 of pregnancy. Additionally, the percentage of the cleaved embryos recovered from the CC-treated rats remained significantly lower consistently from Day 2 of pregnancy, compared to control regimen. These results demonstrate a possible mechanism of CC-mediated inhibition of ovulatory response in the rats which may include the attenuation or blockade of the endogenous secretion of gonadotropins and also suggest that its detrimental effects observed on oocyte normality and embryonic development may be caused by abnormal follicular steroidogenesis( especially elevated estradiol) preceding fertilization.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.383-390
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• 1984

The present paper was carried out to elucidate the effect of salt-treatment and the addition of some food additives on the histamine formation and histidine decarboxylase activity in mackerel muscle during storage under different conditions. The histamine formation was inhibited by salting and histamine was hardly formed regardless of the brine concentraction during storage at $5^{\circ}C$. While, during storage at $25^{\circ}C$, the inhibitory effect upon the histamine formation and histidine decarboxylase activity was in proportion to the increase of the brine concentration. The addition of accidulants such as citric acid, malic acid and succinic acid inhibited the histamine formation and histidine decarboxylase activity. Especially, the histamine contents in the muscle added $10\%$ of citric acid and malic acid was below the critical concentration of poisoning for histamine during storage at $25^{\circ}C$ for 10 days. The histamine formation and histidine decarboxylase activity were inhibited by the $10\%$ addition of D-sorbitol, while there was no significant effect in the case of $5\%$ addition. Generally, the histamine content was increased with histidine decarboxylase activity, but didn't reveal the quantitative correlation ship with the enzyme activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.3
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• pp.435-443
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• 2011

In this study, we evaluated the effects of harvey powder on the fernentation of Yulmoo Kimchi, by measuring sensory, physicochemical, and microbiological properties during fermentation up to 31 days. The Yulmoo Kimchi, with various levels [0, 0.1, 0.2, 0.3, 0.4% (w/w)] of harvey powder, was fermented at $10^{\circ}C$. The product containing the control evidenced the highest scores for appearance and smell. Taste, carbonated taste, texture and overall acceptability were highest in the 0.1% harvey powder and control. During fermentation, titratable acidity increased while pH gradually decreased. Reducing sugar showed no difference at initial fermentation and then steadily decreased. Total vitamin C was gradually decreased during fermentation and reduced sharply after 10 days, and then almost maintained. Total polyphenol content was the highest in the 0.3% harvey powder on day 0 and maintained in all samples thereafter. Antioxidant effect of the Yulmoo Kimchi with 0.1% harvey powder was shown to be the highest. Also, the time required to achieve maximum levels of lactic acid bacteria, as determined by log numbers of cells and total viable cells, were more delayed in the experimental groups with added harvey powder than in the controls. Our results indicated that the Yulmoo Kimchii with below 0.1% added harvey powder was acceptable.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.3
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• pp.253-264
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• 2012

This study was carried out to investigate growth characteristics, yield, chemical compositions and nutrients yield of corn hybrids for silage in the newly reclaimed hilly land. The experimental design was arranged in a randomized block design with three replications. The seeding time was at May 6. The harvest time of four treatments was milk stage (97 days), dough stage (105 days), yellow stage (112 days) and late yellow stage (119 days after seeding). Plant height, ear height, leaf numbers and ear length were highest in yellow stage (p<0.05, 0.01), but dead leaf, stem hardness and sugar degree (Brix) were higher in late yellow than other treatments. Leaf width, tip filling degree and fresh yield were not significantly different. Dry matter yield increased as the maturity stage progressed (p<0.01). Crude protein and crude fat were not significantly different. NDF and ADF decreased as the maturity stage progressed (p<0.01). Ca content was the highest at milk stage (p<0.05), Fe and P were the highest at dough stage (p<0.05, 0.01). However another minerals were not significantly different. Essential amino acid (EAA), nonessential amino acid (NEAA) and total amino acid were highest at yellow stage, but no significant differences were found among the treatments. Total free sugar contents were higher in the order of Milk > dough > yellow > late yellow stage, but no significant differences were found among the treatments. Crude protein yield was the highest at yellow stage, but crude fat yield, amino acid yield and TDN yield were highest at late yellow stage (p<0.01). Total mineral yield showed no significant difference. Based on the above results, yellow and late yellow stage compared to other maturity stage have been shown to increase dry matter yield and nutrients yield, when silage corn grow cultivate in the newly reclaimed hilly land.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.179-187
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• 2016

This study was conducted to determine the impact of elevated temperature and $CO_2$ concentration based on climate change scenario on growth and fruit quality of pepper (Capsicum annuum L. cv. Muhanjilju) with SPAR (Soil Plant Atmosphere Research) chamber. The intraday temperatures of climate normal years fixed by $20.8^{\circ}C$ during the growing season (May 1~October 30) of climatic normal years (1971~2000) in Andong region. There were treated with 4 groups such like a control group (ambient temperature and 400ppm $CO_2$), an elevated $CO_2$ group (ambient temperature and 800ppm $CO_2$), an elevated temperature group (ambient temperature+$6^{\circ}C$ and 400ppm $CO_2$) and an elevated temperature/$CO_2$ group (ambient temperature+$6^{\circ}C$ and 800ppm $CO_2$). Compared with the control, plant height, branch number and leaf number increased under the elevated temperature and elevated temperature/$CO_2$ group. However, leaf area and chlorophyll content showed a tendency of decreasing in the elevated temperature group and elevated temperature/$CO_2$ group. The number of flower and bud were decreased in the elevated temperature and elevated temperature/$CO_2$ group (mean temperature at $26.8^{\circ}C$) during the growth period. The total number and the weight of fruits were decreased in the elevated temperature group and elevated temperature/$CO_2$ group more than the control group. While the weight, length and diameter of fruit decreased more than those of control as the temperature and $CO_2$ concentration increased gradually. This result suggests that the fruit yield could be decreased under the elevated temperature/$CO_2$ ($6^{\circ}C$ higher than atmospheric temperature/2-fold higher than atmospheric $CO_2$ concentration), whereas the percentage of ripen fruits after 100 days of planting was increased, and showed earlier harvest time than the control.

• Korean Journal of Environmental Biology
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• v.32 no.1
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• pp.58-67
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• 2014

The outdoor mass cultivation is not possible for microalgae in Korea all year round, due to cold winter season. It is not easy to maintain proper level of productivity of microalgae even in winter. To prevent a drastic decrease of temperature in a greenhouse, two layers were covered additionally, inside the original plastic layer of the greenhouse. The middle layer was made up of plastic and the inner layer, of non-woven fabric. Acrylic transparent bioreactors were constructed to get more sunlight, not only from the upper side but also from the lateral and bottom directions. In winter at freezing temperatures, six different culture conditions were compared in the triply covered, insulated greenhouse. Wastewater after anaerobic digestion was used for the cultivation of microalgae to minimize the production cost. Water temperature in the bioreactors remained above $10^{\circ}C$ on average, even without any external heating system, proving that the triple-layered greenhouse is effective in keeping heat. Algal biomass reached to 0.37g $L^{-1}$ with the highest temperature, in the experimental group of light-reflection board at the bottom, with nitrogen and phosphorus removal rate of 92% and 99%, respectively. When fatty acid composition was analyzed using gas-chromatography, linoleate (C18 : 3n3) occupied the highest proportion up to 61%, in the all experiment groups. Chemical oxygen demand (COD), however, did not decrease during the cultivation, but rather increased. Although the algal biomass productivity was not comparable to warm seasons, it was possible to maintain water temperature for algae cultivation even in the coldest season, at the minimum cost.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.3
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• pp.151-158
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• 2002

In Korean high yielding varieties developed by crosses between indica and japonica rice, the most limiting factor for yield increase may be attributed to the less number of tillers per unit area. The goal of this study is to find out the effect of the environmental factors as well as cultivation practice on the development and increase of tillers of Dasanbyeo, the high yielding indica / japonica hybrid cultivar. The effect of temperature was examined with 3 different light intensity, 220,600, and 1220 $\mu$㏖/s/$m^2$, respectively. For all the experiments, the leading japonica variety in Korea, Hwaseongbyeo, was used fur the check cultivar for the comparison with Dasanbyeo. The increase of the tillers was more prominent in Dasanbyeo than in Hwaseongbyeo at 220 $\mu$㏖/s/$m^2$ of light intensity, while the similar increase of tiller no. was found at 600 $\mu$㏖/s/$m^2$ of light intensity treatment. However, Hwaseongbyeo showed more rapid increase of tiller at 1220 $\mu$㏖/s/$m^2$ of light intensity. The mean number of the primary tiller ranged 5 to 7 in Dasanbyeo, and 2 to 7 in Hwaseongbyeo, showing greater variation in the latter case. However, the secondary tiller number ranged from 2 to 13 for the former, and 2 to 12 for the latter. The earliest initiation of tiller node of Dasanbyeo and Hwaseongbyeo was observed on 6 and 4 days after transplanting(DAT), respectively, at 600 $\mu$㏖/s/$m^2$ of light intensity, while 10, and 7 DAT, respectively, at 1,220 $\mu$㏖/s/$m^2$. No cultivar difference was observed at 600 $\mu$㏖/s/$m^2$ with the 18 DAT. The ratio of effective tiller was lower in Dasanbyeo, ranging from 47 to 55% than in Hwaseongbyeo, ranging from 72 to 100%.