• Journal of Aquaculture
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• v.9 no.3
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• pp.195-203
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• 1996

Six strains (OKK, MOK, CHA, WON, 505 & PUA) of Korean rotifer, Brachionus plicatilis (S-type) were isolated from salt pond, and the resting egg production of these strains was investigated with the different salinities (10, 20, 30 put), Rotifer were cultured at $28^{\circ}C$ and 2,000 lux in 20 ml test tube with feeding Nannoohloris oculata. The maximum rotifer density was 2,050 inds./ml at 10 ppt for OKK strain, and MOK strain showed the highest specific growth rate (1.028) at 10 ppt. Mixis rate of CHA and WON strains increased with the lower salinity, while MOK strain increased the rate with salinity. PUA strain did not show the mixis rate even at the high rotifer density, and OKK strain showed the very low mixis rate ranging from 1.1 to $3.0\%$. Fertilization rate of CHA, MOK, SOS and WON strains was ranged from 10.4 to $68.8\%$, and OKK strain did not showed any fertilization rate. The highest production of resting egg in 20 ml test tube was 4,065 eggs at 10 ppt for WON strain. The results may suggest that the selection of rotifer strain and salinity are important factors for the mass production of resting egg.

• KSBB Journal
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• v.11 no.3
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• pp.303-310
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• 1996

The marine microalga Isochrysis galbana Parke was studied to optimize its growth conditions in flask culture. Important medium components studied include nitrogen source, buffer, trace elements and vitamins. Environmental conditions include pH, temperature, light intensity, mixing extent and working volume. The medium prepared from natural sea-waters gave a higher final cell density than the medium prepared from synthetic sea-water Nitrate was a better source than ammonium. In the range of 0.4∼2mM, the final cell density was proportional to the initial nitrate concentration and the cell yield was estimated to be 8.5g dry cell wt/g N. For phosphate, optimal growth was observed in 0.1∼1.0mM but a considerable variation in pH was resulted. The addition of Tris at 5mM or 7mM could stabilize the medium pH, but this significantly reduced both growth rate and final cell density, The effect of trace elements and vitamins was negligible. Optimal temperature and initial pH were $20^{\circ}C$ and 8. When the intensity of incident light was varied in the range of 400∼2100 lux, the growth rate increased from 10mL to 70mL, the final cell density decreased although the initial growth rate did not change. Optimal agitation speed was 100rpm when working volume was 30mL. With optimal conditions, the maximum specific growth rate obtained was 0.021hr-1 and the final cell density was 1.1g/L.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.430-434
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• 2001

The algicidal activity of Shewanella (formerly Alteromonas) sp. SR-14 against diatom, Chaetoceros calcitrans was reported in our previous papers. In this study, the effect of Vibrio alginolyticus on the algicidal activity of Shewanelia sp, SR-14 was examined under the optimum algicidal conditions, i.e., temperature ($21\pm1^{\circ}C$), light intensity (4,000 lux), and light: dark cycle (12 hour: 12 hour). Shewanella sp. SR-14 grew well in the presence or the absence of V. alginolyticus in Conwy medium. Algal growth was only inhibited by Shewanella sp. SR-14. V. alginolyticus did not show the algicidal activity, Growth of C. calcitrans increased synergistically with growth of V. alginolyticus. When the initial inoculum of V. alginolyticus was only 1 log cycle higher than that of Shewanella sp. SR-14, the effect of V. alginolyticus on the algicidal activity of Shewanella sp. SR-14 was insignificant during incubation of mixed culture, i.e., two bacterial species and the alga. However, when V. alginolyticus dominated Shewanella sp. SR-14 by 3 log cycles of bacterial counts, it was found that the strain SR-14 could not inhibited growth of C. calcitrans up to 5 days of incubation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.188-199
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• 1996

The native ecological environment and aromatic constituents of Korean wild Codonopsis lanceolata and one Japanese strain were investigated to find Codonopsis lanceolata strains showing high aromatics, and to know regional differences among these strains. The results were as follows : There were no remarkable differences among the Korean wild C. lanceolata strains in ecological environments. Recovery yield of essential oils was highest in Togyusan strain with 0.009%. Difference in protein band patterns among these strains was not recognized, and peroxidase and esterase pattern changes were appeared in different collected regions at the leaf and root tissues. Major aromatic constituents were 11 kinds of aliphatic alcohols such as trans-2-hexenal, 1-hexanol, cis-3-hexanol, and trans-2-hexanol. And Togyusan strain, Sobaeksan strain, and Kayasan strain have the highest aliphatic alcohols of plant essential oils. In particular, BHT(butylated hydroxytoluene), one of the antioxidants, was detected in Chirisan strains.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.269-275
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• 2014

A standard rose cultivar, 'Love Letter' was selected for cut flower from the progenies of a cross between 'Red Giant' and 'Ensemble' by the rose breeding team of the Gyeonggi-do Agricultural Research & Extension Services (GARES) in 2011. A standard rose cultivar 'Red Giant' with red colored (RHS Red Group 45C) petals and 1.8 prickles per stems of 10 cm was used as a mother plant. A standard rose cultivar 'Ensemble' with white and red purple colored (RHS White Group 155C + RHS Red Group N57B) petals and 2.4 prickles per stems of 10 cm was used as a pollen parent. 'Love Letter' was crossed in 2007 and seedlings were produced. After tests of specific characters from 2008 to 2011, this cultivar was finally selected and named. As a standard type with large sized flower, it has red colored (RHS Red Group 46A) petals with 9.3 cm flower diameter and 32.4 petals per flower. Vase life of this cultivar could be as long as 12 days. It takes 43 days from pruning to blooming and cut flower productivity was 152 stems/$m^2$ in a year. The stems of cut flower have no thorn and the length is about with 70.5 cm. When this cultivar grew below $15^{\circ}C$ and 1,000 lux, the petals color became dark red in winter season. 'Love Letter' was registered as a new cultivar on Korea Seed & Variety Service (KSVS) with No. 4482 on May 8, 2013.

• Korean journal of applied entomology
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• v.18 no.1 s.38
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• pp.35-41
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• 1979

Four to $17\%$ of the seeds of ginseng (Panax ginseng Meyer) collected from seemingly healthy plants carried Colletotrichum panacicola Nakata et Takimoto whereas the seeds from the plants with anthracnose sympotoms carried $42\%$ of the same fungus. Prevalent organisms isolated other than C. panacicola from seeds of both kinds of plants were Fusarium, Alternaria, Phoma, Trichoderma and others, ana in that order on acidified potato sucrose agar. C. panacicola also was isolated from 18 months old herbarium specimens. The fungus in the infected tissues also survived during the Korean winter months either on the soil surface or in the soil at 10 and 30 em in depth. When conidial suspensions of C. panacicola were inoculated on detached ginseng leaves, anthracnose symptoms occurred from 25 to $35^{\circ}C$. No symptoms occurred at temperatures below $17^{\circ}C$. Direct sunlight increased significantly the number of anthracnose lesions over those obtained in leaves inoculated in darkness or in 400 lux of fluorescent light. The lesions decreased as age of the leaves increased or as the number of conidia applied decreased. Optimum temperature for mycelial growth and conidial formation of C. panacicola was $25^{\circ}C$. Optimum pH for the mycelial growth was at $pH\;2.8\~4.6$ while the most conidial formation occurred at $pH\;5.2\~5.8.$. When fungicides were applied in the field to ginseng plants with a conidial suspension of C. panacicola, the most effective control of the anthracnose disease was by spraying with difolatan, and followed by maneb, zineb, captan and phaltan; Bordeaux mixture and ferbam were significantly less effective but significantly better than the inoculated control plants.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.477-484
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• 2002

Ninety pre-puberal (6-7 months) female and 15 pre-puberal male Black Bengal goats were collected on the basis of their phenotypic characteristics from different parts of Bangladesh. Goats were reared under semi-intensive management, in permanent house. The animals were vaccinated against Peste Des Petits Ruminants (PPR), drenched with anthelmentics and deeped in 0.5% Melathion solution. They were allowed to graze 6-7 h along with supplemental concentrate and green forages. Concentrates were supplied either 200-300 g/d (low level feeding) or quantity that supply NRC (1981) recommended nutrient (high level of feeding). Different physiological, productive and reproductive characteristics of the breed were recorded. At noon (temperature=$95^{\circ}F$ and light intensity=60480 LUX) rectal temperature and respiration rate of adult male and female increased from 100.8 to $104.8^{\circ}F$ and 35 to 115 breath/min, indicated a heat stress situation. Young female attain puberty at an average age and weight of 7.2$\pm$0.18 months and 8.89$\pm$0.33 kg respectively. Mean age and weight at 1st kidding were 13.5$\pm$0.49 months and 15.3$\pm$0.44 kg respectively. It required 1.24-1.68 services per conception with an average gestation length of 146 days. At low level of feeding the postpartum estrus interval was 37$\pm$2.6 days, which reduced (p<0.05) with high feeding level to 21$\pm$6.9 days. Kidding interval also reduced (p<0.05) from 192 d at low feeding level to 177 d at high feeding level. On an average there were two kiddings/doe/year. Average litter sizes in the 1st, 2nd, 3rd and 4th parity were 1.29, 1.71, 1.87 and 2.17 respectively. Birth weights of male and female kids were 1.24 and 1.20 kg respectively, which increased (p<0.05) with better feeding. Although kid mortality was affected (p<0.05) by dam's weight at kidding, birth weight of kid, milk yield of dam, parity of kidding, season of birth, but pre-netal dam's nutrition found to be the most important factor. Kid mortality reduced from 35% at low level of feeding to 6.5% at high level of feeding of dam during gestation. Apparently, this was due to high (p<0.05) average daily milk yield (334 vs. 556 g/d) and heavier and stronger kid at birth at high feeding level.

• Development and Reproduction
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• v.20 no.2
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• pp.119-125
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• 2016

This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank ($100m^3$) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of $17.0^{\circ}C$. Spawning continued until June 12, 2014, with the water temperature set at $20.5^{\circ}C$. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was $4,449{\times}10^3$. The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were $1.388{\pm}0.041mm$ and $0.378{\pm}0.029mm$, respectively, which was higher in early eggs than in those from late during the spawned period.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.215-215
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• 2017

The preference for domestic cereal crop of Setaria Italica has been increased with the recent interest in healthy foods. However, the productivity of Korean domestic produce, which has been decreasing due to the lack of cultivation technology and the low rate of mechanization during cultivation. Increase of germination ability will have a positive effect on the cultivation by reducing the labor of the manpower consuming and weeding work. Therefore, red light, ultrasonication, liquid priming and liquid smoke treatment that are effective for the germination of the seeds evaluated. The seeds of 1.4mm or more were used for the experiment. The priming solution used in the experiment was 1% $KH_2PO_4$ (74mM). During the priming, the light treated seeds at 2000 lux for 15, 30, 60 and 120 minutes. Ultrasonicationd treatment was performed for 5, 10, and 20 minutes at exposures of 60%, 80%, and 100% of ultrasound up to 21.6 kHz during priming. Light or ultrasound treated seeds transferred to priming treatment at $15^{\circ}C$ for 24 hours. The treatment of the liquid smoke was divided into the treatment of the liquid smoke alone and the treatment of the liquid smoke with the priming. The liquid smoke alone was diluted with distilled water without priming solution and the treatment of the liquid smoke was diluted with the salt priming solution. Both treatments were performed at 0.0%, 0.5%, 1.0%, 5.0%, and 10.0% of the liquid smoke (pH7) concentration at $15^{\circ}C$ for 6 hours. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$ for 24 hours. All treatments showed better results than the non-treated control. Light treatment for 120 minutes improved for germination percentage (GP), Germination uniformity (GU) and heath seed percentage (HS). Ultrasonication treatment was most effective when treated with ultrasound at 21.6 kHz for 5 minutes in all germination characteristics. Ten % of the liquid smoke increase in 92% GP, 1.8 days MGT, $54%{\cdot}day^{-1}GR$, 0.76 GU and 88% HS comparing to non-treated control (72% GP, 2.3 days MGT, $45%{\cdot}day^{-1}GR$, 1.48 GU, and 63 % HS). This study showed that it is possible to obtain high germination by adding liquid smoke treatment to the seeds supplied to the farmers. The efficacy of light, ultrasonication, inorganic salt priming, and liquid smoke treatment on the seeds found in the experiment will be a positive alternative to labor force problems in the cultivation by improving germination.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.224-228
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• 2012

BACKGROUND: This experiment was conducted to investigate the effects of red light on inhibition of flowering and vegetative growth of perilla (Perilla Frutescens. L). METHODS AND RESULTS: To determine red light intensity for inhibiting floral induction of perilla 6h light plus daylength extension (17:00-23:00) with three different intensity of red lights 0.046, 0.114 and $0.177{\mu}mol/m^2/s$ were treated respectively, and control plants were grown under 11(06:00-17:00)/13(17:00-06:00)h light/dark environment. Red(660nm) and far-red(730nm) light were irradiated for night break treatment subsequently to investigate photoreversible flowering response of perilla 'Manchu'. The flowering was inhibited by night break with red light, but sequential far-red light induced floral induction of perilla. Perilla not flowered by red light intensity over $0.177{\mu}mol/m^2/s$. Red light of $0.2{\mu}mol/m^2/s$ was irradiated for 6 hours (20:00-02:00) with LEDs device in plastic house. Perilla not flowered and continued the vegetative growth by red light treatment and the plant length, number of leaves, fresh weight, and leaf area of perilla were increased by 3%, 7%, 21%, and 19%, respectively, compared to incandescent control. CONCLUSION: These results showed that red(660nm) light for daylength extension could be used to control flowering and to enhance production of perilla leaf.