• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.59-68
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• 2011

Research was initiated to investigate the effect of high water-absorbing polymer on turf grass quality of three major turfgrasses. A total of 12 treatment combinations were used in the study. Treatments were made with different rates of sand, soil organic amendment (SOA), and water-swelling polymer (WSP). Visual turf grass quality was evaluated in creeping bentgrass (Agrostis palustris Huds., CB), Kentucky bluegrass (Poa pratensis L., KB), and zoysiagrass (Zoysia japonica Steud., Zoy) grown under greenhouse conditions. Significant differences were observed among the treatments in CB, KB, and Zoy. Visual quality ratings varied with mixing rates of SOA and WSP, being maximum 5.6 in differences among them. At the end of study it ranged from 0.3 to 9.6 in CB, 0.3 to 4.0 in KB, and 0.9 to 5.8 in Zoy. Turfgrass quality pattern changed with time after seeding among treatments influenced by WSP rates. From this study, a proper rate of WSP is considered to be 5%, 5~10%, and 5% for CB, KB and Zoy, respectively. In general, overall treatment effect of WSP on turfgrass quality was highly associated with SOA 20% in three turtgrass species. When mixing sand with SOA and WSP for rootzone soil, a proper rate of SOA is considered to be 15 to 20% for CB and KB, while 20% for Zoy of warm-season grass. A further study would be required to investigate the effect of varied, gradual mixing rates of WSP on growth characteristics of turfgrasses grown on mixtures of sand, SOA, and WSP before a field application.

• Korean journal of applied entomology
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• v.24 no.1 s.62
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• pp.25-28
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• 1985

Experiments were carried out to investigate the life cycle of the rice leaf beetle (RLB), (Oulema oryzae KUWAYAMA) ,yield losses by its damages, and control method in $1976{\sim}1983$ at the experimental field of Gangweon PORD. Peak occurrence of adult and larva rice beetle was late May and mid-June, respectively. Adult overwintered in the forest of mountain and move into the paddy field to lay eggs on the rice leaf from late seedling stage. A female adult laid eggs for 2 days, and egg, larval and pupal period was 9, 16, and 9 days, respectively. Leersia japonica MAKINO was damaged slightly by the beetle. The yield reduction by artifical defoliation ranged from 6 to 40% and yield reduction increased as leaf feeding delayed until mid-July. All insecicides show 100% of control value against RLB.

• Korean journal of applied entomology
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• v.31 no.3
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• pp.205-240
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• 1992

In reality, it is a green revolution of the entire agricultural matrix in Korea that integrated pest control plays an important role in the possible breakthrough in rice self-sufficiency. In paddy agroecosystem as man-modified environment, rice is newly established every year by transplantation under diverse water regimes which affect a microclimate. Standing water benefits rice by regulating the microclimate, but it favors the multiplication of certain pets through the amelioration of the microclimate. Further, the introduction of high yielding varieties with the changing of cultural practices results in changing occurrence pattern of certain pests. In general, japonica type varieties lack genes resistant to most of the important pests and insect-borne virus diseases, whereas indica type possesses more genes conferring varietal resistance. Thus, this differences among indica type, form the background of different approaches to pest management. The changes in rice cultivation such as double cropping, growing high-yielding varieties requiring heavy fertilization, earlier transplanting, intensvie-spacing transplanting, and intensive pesticide use as a consequence of the adoption of improves rice production technology, have intensified the pest problems rather than reduced them. The cultivation of resistant varieties are highly effective to the pest, their long term stability is threathened because of the development of new biotypes which can detroy these varieties. So far, three biotypes of N. lugens are reported in Korea. Since each resistant variety is expected to maintain several years the sequential release of another new variety with a different gene at intervals is practised as a gene rotation program. Another approach, breeding multilines that have more than two genes for resistance in a variety are successfully demonstrated. The average annual rice losses during the last 15 years of 1977-’91 are 9.3% due to insect pests without chemical control undertaken, wehreas there is a average 2.4% despite farmers’insecticide application at the same period. In other words, the average annual losses are prvented by 6.9% when chemical control is properly employed. However, the continuous use of a same group of insecticides is followed by the development of pest resistance. Resistant development of C. suppressalis, L. striatellus and N. cincticeps is observed to organophosphorous insecticides by the mid-1960s, and to carbamates by the early 1970s in various parts of the country. Thus, it is apparent that a scheduled chemical control for rice production systems becomes uneconomical and that a reduction in energy input without impairing the rice yield, is necessarily improved through the implementation of integrated pest management systems. Nationwide pest forecasting system conducted by the government organization is a unique network of investigation for purpose of making pest control timely in terms of economic thresholds. A wise plant protection is expected to establish pest management systems in appropriate integration of resistant varieties, biological agents, cultural practices and other measures in harmony with minimizing use of chemical applications as a last weapon relying on economic thresholds.

• Korean Journal of Poultry Science
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• v.35 no.1
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• pp.29-37
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• 2008

This study was evaluated the oxidative stability of the breast and leg meat from chicken fed extract of medicinal herb mix (Lonicera japonica Thunberg : Morus alba L. : Coptis chinensis = 48.5 : 48.5 : 3.0%) and antibiotics (Albac G150). Ross chickens were divided into three treatments: basal diet (control), basal diet with antibiotics (0.05%) and basal diet with extract of medicinal herb mix (0.3%). They were fed the experimental diets for 35 days and slaughtered. After that, the breast and leg meat samples were stored at $4^{\circ}C$ for 10 days. Total phenol content of breast meat in Ross chicken fed extract of medicinal herb mix was higher than that of antibiotics treatment and control during storage. DPPH radical scavenging activity was the highest in leg meat of Ross chicken fed extract of medicinal herb mix at 0 day. $ABTS^+$ reduction activity was higher in chicken meat fed extract of medicinal herb mix than antibiotics treatment and control. This results showed that the diet with extract of mixed medicinal herb was more effective in oxidative stability of chicken meat than basal diet and diet with antibiotics.

• Korean Journal of Ichthyology
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• v.18 no.2
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• pp.119-128
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• 2006

Fish assemblages associated with eelgrass beds and unvegetated area were compared based on specimens collected every month in Jindong Bay. The common fish species were Hexagrammos otakii, Acanthopagrus schlegeli, Lateolabrax japonicus, Pholis nebulosa, P. fangi, Leiognathus nuchalis, Repomucenus valenciennei, and Acanthogobius flavimanus. H. otakii, A. schlegeli, P. nebulosa and L. japonicus were higher abundance in an eelgrass bed than unvegetated area, whereas P. fangi, R. valenciennei and A. flavimanus were higher in unvegetated area. Sillago japonicus, Hippocampus japonica, Takifugu niphobles, Pseudoblennius percoides, Sebastes inermis, Syngnathus schlegeli, Sebastes schlegeli were found in an eelgrass bed, but not in unvegetated area. Most of fish species were primarily small fish species or juveniles of fish species in an eelgrass bed, while larger fish species were found in unvegetated area. The eelgrass bed in Jindong Bay seem to play a nursery role for fishes. Seasonal variations in both species composition and abundance were large in two habitats; higher number of species and individuals occurred May 2002, and April 2002 to July 2002, while biomass was the highest in April 2002 and July 2002. Fish numbers as well as biomass were lowest in January 2002. Species richness, number of individuals and biomass of fishes in an eelgrass bed were significantly higher than those of in unvegetated area. These result suggest that differences in fish species richness and abundances are primarily related to habitat structure. Different habitat preferences were evidenced for the juveniles and adult of several fish species.

• Korean Journal of Soil Science and Fertilizer
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• v.7 no.2
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• pp.107-112
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• 1974

In order to establish a rational application method of potash to paddy rice(Oryza sativa L. Jinheung, a Japonica variety) field and pot experiments on split application of two rates (6kg and 12kg $K_2O$ per 10a) of potash at a certain critical growing stage have conducted in 1973 and the results were as follows: 1. At the treatment where a rate of 6kg $K_2O$ per 10a(lower dose) of potash was supplied in two split doses, a half at transplanting time and the other half at young panicle formation stage, the yield of paddy rice appeatred to be low due to less number of panicles per hill. (Field experiment) 2. The treatment where potash supply ceased at transplanting time or at effective tillering stage but supplied at the other two stages (including panicle initiation stage) have failed to increase K content in the flag leaf and have shown low maturity and low thousand grain weight, which resulted in low paddy rice yield. (pot experiment) 3. From above two facts, it is concluded that the application of potash at transplanting time is an important practice for the high yielding of paddy rice. 4. The application of lime seemed to stimulate later growth of paddy depressing the unnecessary increase of poor miserable tillers in early stages of growth.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.6
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• pp.563-570
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• 1985

The main purpose of this study is to evaluate a revolving plate-type biofilter system for mass culture of eels (Anguilla japonica) based on the experimental rearing for 199 days. Water quality, growth efficiency of fish and effects of fish disease control were critically evaluated. The experiment was conducted in two different units, each unit consisting of a cement tank containing $20m^3$ of water. In unit A, a biofilter which includes 400 rotating undulated P. V. C. plates being 70 cm in diameter which rotates at 6 rpm and also 400 undulated P. V. C. plates fixed in the settling chamber of an area of $66{\times}62cm$. Water was continuously passed through the filter at a rate of 260 l/min., and supplemental water was added to the fish tank at a rate of $4m^3$ a day. In unit B, the biofilter has 400 P. V. C. plates being $66{\times}62cm$ each was installed in the settling tank. The results gained from the experimental rearing for 199 days from April 21, 1984 to November 5, 1984 are as follows. In the growth experiment, the weight of fish in unit A increased from 3.0 kg to 815.6 kg, while in unit B, from 3.0kg to 416.0kg. During the period of the experiment, in the both units the fish grew at an acceptable rate at the temperature at which they were held. Observing every aspect of eel culture, including growth rate, disease control and water quality, unit A appears to have adventages over unit B, which makes it particuraly attractive in intensive recirculating fish culture system. It was further observed that certain parasites such as Trichodina sp. and Costia sp. could easily be controled by appling 4 ppm of $KMNO_4$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.230-238
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• 2014

The purpose of this study was to develop the cost-effective and efficiency seed longevity prediction method of rice (Oryza sativa L.) germplasm for viability monitoring. To find an optimum predicting method for rice seed longevity at genebank, an accelerated ageing (AA) test, a controlled deterioration (CD) test and a dry-heat treatment (DHT) were conducted to the four groups of rice germplasm based on ecotype, such as Indica, Japonica, Javanica and Tongil type. Among the three artificial aging treatments, the dry-heat treatment of 36 hours at $90^{\circ}C$ is suggested as a routine predictive test method of rice germplasm longevity at a genebank. The distribution of germination rate on 3,066 accessions which conserved 26.5 years at $4^{\circ}C$ showed similar trend with the result of distribution by dry-heat treatment at $90^{\circ}C$ on 36 hours using 106 accessions of rice selected samples which composed four ecotype groups. The results show that the dry-heat treatment affect not only predicting the rice seed longevity but also determining effective interval for monitoring germination of rice germplasm in genebanks.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.22-28
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• 2014

Flos Sophorae, the dried flower bud of Sophora japonica L, possesses anti-inflammatory properties, prevents and treats blood capillary and hypertension diseases and can also be used as a hemostat. However, the effect of Flos Sophorae on breast cancer invasion is unknown. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix, is a major component in cancer cell invasion. In this study, we investigated the inhibitory effect of Flos Sophorae extract (FSE) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced Matrix metalloproteinase-9 (MMP-9) expression and cell invasion, as well as the molecular mechanisms involved in Michigan Cancer Foundation-7 (MCF-7) cells. FSE inhibited the TPA-induced transcriptional activation of nuclear factor-kappa B (NF-${\kappa}B$). These results indicate that FSE-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of NF-${\kappa}B$ pathway in MCF-7 cells. Thus, FSE may have therapeutic potential for controlling breast cancer invasiveness.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.295-299
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• 1998

To detect the effects of gelling agent brands and concentration on rice anther culture, anthers of rice(O. sativa L. japonica, cv, Nagdongbyeo) were inoculated on N6-Y1 basic media supplemented with 0.4~1.6% Bacto agar(Difco, 04140-01), Agarose(Sigma, Type 1) and 0.2~0.8% Gelrite(Kelco, 143364) as gelling agents. On 0.4% Bacto agar and Agarose media, the frequency of callus formation which was significantly decreased in proportion to gelling agent's concentration was 39% and 55%, respectively. On 0.6% Gelrite media, the frequency of callus formation which was not statistically significant among the 0.2~0.8% concentration was 44%. Calli derived from the higher concentration of gelling agents showed embryogenic with slow growth, small, whitish and hard shape compare to that of the lower concentration. The frequency of green plant regeneration was high not only in calli derived from the higher concentration but also in plant regeneration medium with the higher concentration after callus transfer. Calli derived from the higher concentration was effective to maintain the frequency of green plant regeneration up to 60 days after anther inoculation. Introduction of 0.6~0.8% Geltite for callus formation, then transferred 1.6% Bacto agar and Agarose or 0.8% Gelrite for green plant regeneration was effective to increase anther culture efficiency.