We studied the infection rate of and various metacercariocidal approaches to controlling Gymnophalloides seoi for prevention of human infection in cultured and natural oysters in Korea. The selected survey areas were Aphae-do (Shinan-gun, Jeollanam-do), which is an endemic area for G. seoi, and Tongyeong (Geonsangnam-do), which is the main production area of oysters in Korea. In the Tongyeong area, the metacercariae of G. seoi were not detected in cultured oysters (0/201) or wild oysters (0/134). Seventy-two G. seoi metacercariae were observed in 33 of 265 natural oysters collected from Aphae-do; however, metacercariae were not detected in the cultured oysters (0/1101) purchased from the Daejeon Fish Market. To investigate the viability of G. seoi metacercariae, various metacercariocidal treatments were used with 3.5% saline and oyster juice used as positive controls. The metacercariae survived for 75.4 h in 3.5% saline and 112.6 h in oyster juice. After the metacercariocidal treatment, G. seoi metacercariae were survived for 13.29 min in tap water, < 20 sec in 4.3% vinegar, no effect in a rinse of the whole oyster body in 70°C water for 1 sec, but 1 sec in a rinse of the whole oyster body in 90°C water for 1 sec. The greatest metacercariocidal effect on G. seoi was from rinsing oysters in 90°C water followed by those from treatment with 20% ethyl alcohol, 4.3% vinegar, and tap water. However, we suggest that the most actual prevention to G. seoi human infection is rinsing the oysters with tap water for at least 30 min.

Chamaecyparis obtusa is one of the economical conifers planted in Korea due to its good quality timber and wood characteristics. Individuals of C. obtusa containing high terpenes (HT) and low terpenes (LT) were selected for by colorimetric method. The HT of C. obtusa was delayed in wilting against various abiotic stresses compared to the LT plants. The HT group exposed to UV did not significant influence the chlorophyll content, and the chlorophyll value was higher in the HT group than the LT group. Also, chilling treatment (5℃) did not significant influence on the chlorophyll content. However treatment at -4℃ showed relatively low chlorophyll content in the LT group than the HT group. Plants exposure to high temperature was not a difference between the HT and the LT group. However, treatment at 38℃ influenced the chlorophyll content that was increased exposure time-dependently. In salt treatments, chlorophyll in the HT group was lower at high concentrations (300 and 500 mM) of NaCl. However, chlorophyll content increased to slightly in treatment time-dependently, which is 6.7% to 40%. H2O2 treatment has been a negative effect on the chlorophyll content in the HT group. All concentration of H2O2 decreased the chlorophyll content of 5% to 35%. Plants containing high terpenoids were resisted against some abiotic stress such as salt and H2O2. Our results implied that terpenoids could cause various abiotic stress resistance. These results could be utilized for efficient management and biomass production during forest silvicultures.

Chrysanthemums (Dendranthema grandiflorum ‘Iwanohakusen’) were grown in a greenhouse with complete nutrient solution system to investigate the effect of silicon (Si) supplement on salt induced deleterious effects in chrysanthemum plants. The experiment was conducted in plastic pots supplemented with a mixture of upland soil : leaf mold : river sand (3:3:4, v:v:v). Si and salinity were treated in combination with two levels of NaCl (0 and 100 mM) and two sources of silicon (K2SiO3, KSi and silicate fertilizer, SiF) at the same concentration (1.8 mM Si) by weekly-drenching for 12 weeks. Chrysanthemum plants supplemented with Si increased in fresh and dry matter enhancing water content and salinity tolerance. The plants grown under salt stress produced less fresh and dry matter than control plant. However, Si supplement to plants under salt stress ameliorated negative effects of salt stress. In soil, EC and NaCl increased by salt stress were mitigated by Si supplement. Salt stress significantly decreased the contents of K and P in leaf, but Si supplement under salt stress significantly recovered the decreased contents with enormous desorption of K and P in soil. Added Si significantly increased content of available SiO2 with its adsorption by salt stress in soil, which was directly related to Si accumulation in leaf. However, Si uptake by roots was suppressed by salt stress irrespective of Si supplement. Si supplement did not ameliorated the negative effects of salt stress on chlorophyll content and membrane integrity in leaf of chrysanthemum plant although significantly increased Si content in leaf, but reversed pest (Liriomyza trifolii) resistance to above-control level.

Geneally, rice seeds regardless indica or japonica are showing low germination ratio or completely lost germination ability together with lost of good eating quality under high temperature and humidity conditions. Thus, this study was designed to evaluate a longevity for conservation of good eating quality during long term storage in rice. For the longevity evaluation, germination ability was studied after 5 days of high temperature and humidity stress (50℃/RH 95%). Dharial, originated from Bangladesh and showing weedy type with red pericarp, was selected as a good donor for longevity genes. A mutant was developed from Dharial through EMS mutagenesis and two populations of Dharial/4*Ilmibyeo and Dharial/4*Gopumbyeo were also developed for genetic study. In the 2-DE analysis followed by MALDI-TOF MS with wild and mutant lines, several candidate genes were identified. In the longevity test of two populations, a few lines showing good germination ability after high temperature and humidity stress were selected and subjected to confirm the relationships between longevity and conservation of good eating quality under long term storage.

This expe끼ment was conducted to evaluate the effect of two different organic acid products as antibiotic replacement in olive flounder paralichthys olivaceus . Fish averaging 3.5 ::!:: 0.05 g(mean ::!:: SD) were fed one of the ten semi-purified diets : Diet 1 ; Control , Diet 2 ; add antibiotics - 50mg OTC / kg body weight / day(OTC), Diet 3; Add organic acid bland A(OABA) - 4g/kg diet, Diet 4 ; add organic acid bland B(OABB) - 4g/kg diet for 10 weeks. Total gut microflora counts were significantly higher in the control group compared to the OTC and organic acid groups(P <0.05). Fish fed OABA, 。ABB and OTC had lower gut Vibrio counts compared to the control, but were not significantly different. Results from the challenge study indicate that mortality in the different treatment groups (50%) was significantly lower than those observed for the control group (100%). There were no differences in mortality between the OTC and organic acid groups. Overall findings from this study indicate that the organic acid blends A and B were as effective as oxytetracycline, an antibiotic, in regulating total gut bacterial numbers, Vibrio counts and providing protection against a pathogen such as Edwardsiella tarda.

An unbalance of rice productions and consumptions caused serious problems in both of agricultural area and grain market of korea. In recently, various efforts for rice processing products such as rice noodles and rice wines are in progress to overcome the unstable rice market. Among them, waxy rice is predominant items in processing rice. However, varietal features of starch viscosity are not considered in the processing industries and rice breeding field. In this study, 12 waxy rices and 2 cultivars Ilmibyeo(japonica) and IR72(Indica) were studied for physicochemical and amylogram to characterize the use of waxy rices. The amylose contents of waxy rices were from 7.1 to 8.1% with soft gel consistency and relatively low alkali digestion value(1.4% KOH) compare to Ilmibyeo. In the amylogram analysis(RVU) of waxy rices, unlikely normal rices, very fast peak time(about 3.5 min.) was obtained compare to that of 6.2 min. of Ilmibyeo. And 2 to 3 groups were classified based on peak viscosity and consitency of RVU. Wangchal, Odorokimochi and Hangangchal showed relatively high peak viscosity seemed not suitable for rice cake due to the hardness speed. And most of waxy rices developed in korea were believed to be suitable for oil fried cakes(Hankwa) because of a certain grade of starch degradation speed. And Mochiminori and Midoromochi originated from japan could be a good sources in waxy rice breeding program to improve the cooking properties especially in slow down of hardness speed with very low peak viscosity, hot viscosity and cool viscosity.

The content and composition of tocopherol were analyzed in peanuts produced in Korea. The tocopherol assay was consisted of an extraction with n-hex-ane:isopropanol mixture followed by high pressure liquid chromatography with fluorescence detection. Tocopherol content was higher in leaves and seeds but lower in seed coats and shells. α -/~gamma - Tocopherol ratio was as low as 0.53 in seeds and as high as 22.5 in shells. Tocopherol content in seeds of nine varieties ranged from 142 to 220 ng/mg dry weight, and the α -/~gamma -tocopherol ratio from 0.40 to 0.75. Tocopherol content decreased by 18% but α -/~gamma -tocopherol ratio increased by 44% in roasted seeds. The results indicate that the level of tocopherol in Korean peanut varieties is moderate and the ratio of α - to ~gamma -tocopherol is low.