• 한국해양학회지
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• v.23 no.2
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• pp.70-75
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• 1988

In order to set up a predictive model for an effective spat collection of ark shells, Anadara broughtonii, the survival rate and the time required for each developmental stage of planktonic larvae were investigated during the period from July 1 to October 30 in 1974, in one of the main ark shell seed collection areas, Chinhae Bay, in the southern part of Korea. The advent of D-shaped larvae ca. $94.3{\times}72.7{\mu}m$ long had three peaks during the surveyed period: August 25, August 31 and September 9, umbo-shaped larvae ca. $141.6{\times}108.4{\mu}m$ and full grown larvae ca. $269.3{\times}221.7{\mu}m$ long also showed three peaks: September 6, September 12 and September 20 for the former, and September 20, September 25 and October 5 for the latter, respectively. About 11 to 12 days was required for D-shaped larvae to develop to umbo-shaped stage. At this intermorphological stage, the daily survival rate was 0.93 with a total survival rate of 45% for the stage. The time required for umbo-shaped larvae to develop to full grown larvae varied from 13 to 15 days with a daily survival rate of 0.93 and with a total survival rate of 36% in the period. Twenty-five to twenty-six days were required for each peak group of the D-shaped larvae to reach a full grown stage, and their total survival rate was 16% during this developmental stage.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.335-342
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• 2010

Sulforaphane (SFN) and total phenolics (TPC) contents and antioxidant activity (AA) were analyzed from 13 radish genotypes (Rhaphanus sativus L.), cultivated at 3 locations with different altitudes (Gangneung: asl 5 m, Jinbu: asl 550 m, and Daegwallyeong: asl 750 m). SFN varied greatly from 0.1 to $120.5{\mu}g{\cdot}g^{-1}$ in dry weight test and was significantly affected by location ($P{\leq}0.001$), genotype ($P{\leq}0.001$) and $location{\times}genotype$ interaction ($P{\leq}0.01$). Radishes, cultivated at Daegwallyeong site, showed higher SFN than those of other locations. Among different genotypes, the root of 'Black radish' and leaves of 'Purunmu' of Daegwallyeong had the highest SFN (107.8 and $120.5{\mu}g{\cdot}g^{-1}$, respectively). TPC in root was affected by genotype ($P{\leq}0.001$), and $location{\times}genotype$ interaction ($P{\leq}0.01$), but not by location. In leaves, TPC was affected by location ($P{\leq}0.01$), genotype ($P{\leq}0.001$), and $location{\times}genotype$ interaction ($P{\leq}0.001$). AA expressed as electron donating ability was significantly influenced by location, genotype and $location{\times}genotype$ interaction and correlated positively with TPC ($Pearson's$ $r$=0.897) in root. These results suggest that radish could be a good source of functional food and high altitude location such as Daegwallyeong has potential for the production of radish with high content of health promoting factors.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.50-55
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• 2013

The objective of this research was to investigate the impact of Ca fertilizer on the growth of mother plants, physiological disorders, and occurrence of daughter plants in propagation of 'Seolhyang' strawberry through plastic bag cultivation. To achieve this, chemicals of 1.125 mM $Ca(OH)_2$, 0.375 mM $MgCl_2$, 1.250 mM KCl were blended and designated to combined fertilizer (CF). Then, the effect was compared to the treatment of no Ca application (control) and a commercial fertilizer, CalMag (13-0-1.9-16-6:N-$P_2O_5$-$K_2O$-CaO-MgO), when those were applied every two weeks with controlled electrical conductivity (EC) of solution such as 0.6 or 1.0 $dS{\cdot}m^{-1}$. The number of plants showing Ca deficiency symptoms was the highest in control treatment, but those decreased significantly in CF or CalMag treatments. The differences between CF and CalMag in appearance of Ca deficient plants were not significant when two fertilizers were applied with same EC. The fresh and dry weights of mother plants were the greater in the treatments of CF or CalMag than those of control treatment. The treatments of 1.0 $dS{\cdot}m^{-1}$ of CF or CalMag were more effective than those of 0.6 $dS{\cdot}m^{-1}$ on the fresh and dry weight of the mother plants. The runner lengths in the treatment of 1.0 $dS{\cdot}m^{-1}$ of CF were the longest among the all treatments tested. The treatments of 1.0 $dS{\cdot}m^{-1}$ were more effective than those of 0.6 $dS{\cdot}m^{-1}$ of CF or CalMag in lengths and fresh and dry weight of runners. The fresh and dry weights of daughter plants were heavier in the treatments of CF than those of CalMag. Based on the above results, we concluded that the Ca deficiency in raising 'Seolhyang' strawberry can be lessened by the application of Ca containing fertilizers, but combined application of Ca, K and Mg was more effective than that of Ca alone for seedling production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.211-218
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• 2003

This study was conducted to select the promising varieties of timothy (va.) Climax, Itasca, Alma, Comtal, Liphlea, Erecta, Argus and Kunpu at Daekwanryong(altitude 800m a.s.l.) and Namwon(altitude 450m a.s.l.) branch, and orchard grass (va.) Potomac, Warrior, Ambassador, Hapsung 2, 20, 93E and Kitamidori at Daekwanryong branch of National Livestock Research Institute, from 1999 to 2002. Among the timothy varieties, leafness of Liphlea, Erecta and Kunpu was greatest. Heading time of Liphlea and Kunpu was earliest and plant length of Kunpu was longest. Also, winter survival of Erecta and Kunpu was greatest with 94.0%. Among the orchardgrass varieties, although heading time of Hapsung 20 was late, it's leafness was the best and plant length was the longest in all varieties. Also, winter survival of Hapsung 20 was the highest in all varieties. In Daekwanryong and Namwon, dry matter yield of timothy(va.), Kunpu was highest(P<0.05) among the timothy varieties with 9,493kg and 13,890kg/ha, respectively. Dry matter yields of orchardgrass(va.), Hapsung 2 and Hapsung 20 were greatest among the varieties with 8,690kg and 8,818kg/ha, respectively. In two areas, average ADF concentration of Climax was lowest with 33.4%, and NDF concentration of Argus was lowest with 65.4% in all varieties. Average crude protein content of Alma was the highest with 16.5% and that of Kunpu was the lowest with 13.9%. Average crude protein yield of Kunpu was the highest with 1,710.5kg/ha in all timothy varieties. The ADF concentration of Hapsung 20 was lowest (33.4%), and NDF concentration of 93E was lowest (67.5%). Crude protein content (13.5%) and crude protein yield (1,173.2kg/ha) of Hapsung 2 were highest. These results indicate that Kunpu and Liphlea would be the promising varieties of timothy in Daekwanryong and Namwon, and also, Hapsung 2 of orchardgrass would be the promising varieties in Daekwanryong.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.70-82
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• 2015

This study was conducted to establish an efficient screening system to identify melon resistant to Fusarium oxysporum f. sp. melonis. F. oyxsporum f. sp. melonis GR was isolated from infected melon plants collected at Goryeong and identified as F. oxysporum f. sp. melonis based on morphological characteristics, molecular analyses, and host-specificity tests on cucurbits including melon, oriental melon, cucumber, and watermelon. In addition, the GR isolate was determined as race 1 based on resistance responses of melon differentials to the fungus. To select optimized medium for mass production of inoculum of F. oxysporum f. sp. melonis GR, six media were tested. The fungus produced the most spores (microconidia) in V8-juice broth. Resistance degrees to the GR isolate of 22 commercial melon cultivars and 6 rootstocks for melon plants were investigated. All tested rootstocks showed no symptoms of Fusarium wilt. Among the tested melon cultivars, only three cultivars were susceptible and the other cultivars displayed moderate to high resistance to the GR isolate. For further study, six melon cultivars (Redqueen, Summercool, Superseji, Asiapapaya, Eolukpapaya, and Asiahwanggeum) showing different degrees of resistance to the fungus were selected. The development of Fusarium wilt on the cultivars was tested according to several conditions such as plant growth stage, root wounding, dipping period of roots in spore suspension, inoculum concentration, and incubation temperature to develop the disease. On the basis of the test results, we suggest that an efficient screening method for melon plants resistant to F. oxysporum f. sp. melonis is to remove soil from roots of seven-day-old melon seedlings, to dip the seedlings without cutting in s pore s uspension of $3{\times}10^5conidia/mL$ for 30 min, to transplant the inoculated seedlings to plastic pots with horticulture nursery media, and then to cultivate the plants in a growth room at 25 to $28^{\circ}C$ for about 3 weeks with 12-hour light per day.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.638-646
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• 2015

To increase the utility of seeds in plant resources, seeds of 6 Aster species(A. incisus, A. hayatae, A. koraiensis, A. scaber, A. spathulifolius, and A. yomena) were subjected to experiments to develop adequate methods for sprout production. To study optimum germination conditions, germination rates of the seeds were analyzed at different temperature (15, 20, 25, and $30^{\circ}C$) and light conditions. A longitudinal growth experiment was performed in dark conditions for 10 days. Seedlings, with optimum germination rate and longitudinal growth, were placed in the light for 0-3 days to seek the adequate greening periods. Sprouts grown under optimum environmental conditions were placed in vessels with or without ventilation, and stored under $4^{\circ}C$ and $10^{\circ}C$ to examine storage environment and period. As a result of this analysis, seeds were selected that germinated over 50% within 12 days. Longitudinal growth was promoted at $20-25^{\circ}C$, and optimum growth was obtained with 7-9 days. As greening days increased longitudinal growth was retarded, but orbital growth of radicles and cotyledons was promoted. Considering all these factors, greening treatment of 2 days showed the best results. In a storage ability experiment, the best result was achieved by storage in vessels without ventilation under $4^{\circ}C$. Ventilation prevented rotting of sprouts, but reduced moisture contents of sprouts. Most sprouts were fresh at $4^{\circ}C$ for 3-6 days. In particular, sprouts of A. hayatae and A. yomena had high keeping quality, and remained fresh over 3 days even at $10^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.32 no.2
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• pp.154-162
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• 2017

The purpose of this study was to investigate the microbial reduction effect of chlorine dioxide and sodium hypochlorite in Korean chive. Korean chive inoculated with foodborne pathogens at the level of approximately 7~8 log CFU/g was treated with various concentration of chlorine dioxide (3, 4, 10, 25 and 100 ppm and sodium hypochlorite (100, 150 and 200 ppm) for 5, 10, 30 and 60 minutes. The treatment of 150 ppm sodium hypochlorite and 50 ppm chlorine dioxide for 30 min reduced the number of total bacteria in Korean chive up to 2.0 log CFU/g. Reduction of microbial levels was observed for all concentrations of sanitizers but their effectiveness did not correspond to their concentration. Due to the quality degradation, 50 ppm chlorine dioxide was not appropriate for Korean chive. Most effective reduction of microbial levels was observed when Korean chive were treated with 9 times more sanitizer in volume. For field application, the treatment of 150 ppm sodium hypochlorite showed 2.7 and 4.0 log CFU/g reductions for numbers of total bacteria and coliforms, respectively. Therefore, washing with sodium hypochlorite of a ratio of 1:9 (Korean chive : 150 ppm sodium hypochlorite (w/v)) for 30 minutes can reduce the number of foodborne pathogen in Korean chive.

• Current Research on Agriculture and Life Sciences
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• v.26
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• pp.63-69
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• 2008

The varietal difference, effect of root amounts and cultivation duration on the asparagine content of soybean sprouts, which is known to have the excellent detoxifying effect of ethanol, were investigated for developed varieties and indigenous sprout lines to establish cultivation methods of increasing the asparagine content and to develop soybean varieties having high asparagine content. Some of the research results obtained are summarized as follows; 1. Range and mean of asparagine content of 174 germplasm were 0.38~1.67% and 0.99%, respectively, on fresh weight basis. 2. Developed sprout-soybean varieties showed somewhat higher asparagine content of 1.29% than that of indigenous sprout lines of 0.96% on fresh weight basis. 3. No significant difference in asparagine content among the seed size groups was recognized though the highest asparagine content, 1.02% on fresh weight basis was observed in the seed size of 8.1~10.0g/100 seeds. 4. Among the seed coat color groups, soybean of brown seed coat color showed the highest asparagine content (1.15%) on fresh weight basis. No difference was observed among other groups of seed coat color. 5. Range of asparagine content of 174 varieties was 4.08~6.24% on dry weight basis. Soybean varieties that showed high asparagine content were Dawonkong, Sobacknamulkong, Sowonkong, and Somyungkong, with the contents of 6.24%, 6.21%, 5.95%, and 5.85%, respectively. 6. Amount of roots which have the highest asparagine content out of sprout parts was greatly increased up to 10 days of sprout cultivation. 7. Highly significant difference in asparagne content of sprout was recognized between those grown for five and ten days, with the asparagine content of 0.68% and 1.21%, respectively, on fresh weight basis. 8. Asparagine content of hypocotyle part was also highly proportional to days to cultivation; it increased from 2.91% at 2 days of cultivation to 15.68% on fresh weight basis at 14 days of cultivation.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.77-83
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• 2016

The measurement of total fresh weight of plants provides an essential indicator of crop growth for monitoring production. To measure fresh weight without damaging the vegetation, image-based methods have been developed, but they have limitations. In addition, the total plant fresh weight is difficult to measure directly in hydroponic cultivation systems because of the amount of nutrient solution. This study aimed to develop a real-time, precise method to measure the total fresh weight of Romaine lettuce (Lactuca sativa L. cv. Asia Heuk Romaine) with growth stage in a plant factory using a nutrient film technique. The total weight of the channel, amount of residual nutrient solution in the channel, and fresh shoot and root weights of the plants were measured every 7 days after transplanting. The initial weight of the channel during nutrient solution supply (Wi) and its weight change per second just after the nutrient solution supply stopped were also measured. When no more draining occurred, the final weight of the channel (Ws) and the amount of residual nutrient solution in the channel were measured. The time constant (${\tau}$) was calculated by considering the transient values of Wi and Ws. The relationship of Wi, Ws, ${\tau}$, and fresh weight was quantitatively analyzed. After the nutrient solution supply stopped, the change in the channel weight exponentially decreased. The nutrient solution in the channel slowly drained as the root weight in the channel increased. Large differences were observed between the actual fresh weight of the plant and the predicted value because the channel included residual nutrient solution. These differences were difficult to predict with growth stage but a model with the time constant showed the highest accuracy. The real-time fresh weight could be calculated from Wi, Ws, and ${\tau}$ with growth stage.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.119-123
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• 1986

The study was conducted to find out the gene effects on body weights at weaning and at the age of 60 days in mice, with 343 progenies from full-dialell crosses of four lines of BALB/c, CBA, C3H and C57BL. The progenies were reared at the Experimental Animal Farm, College of Agriculture, Kyungpook National University from November, 1984 to February, 1985, and data collected from the progenies were analyzed into general combining ability, maternal effects, specific combining ability and reciprocal effects with Harvey's model. General combining ability effects estimated in line-crosses were -0.6033~0.5298 for weaning weights and -0.5086~1.0012 for body weights at the age of 60 days. General combining ability for BALB/c and C57BL were significantly better than general combining ability for CBA and C3H for both traits (P<0.05). Maternal effects for C3H were significantly larger than the maternal effects of BALB/c for both traits (P<0.05). The estimates of maternal effects were -0.9678~0.4609 for weaning weights and -1.1886~0.0729 for body weights at the age of 60 days. Specific combining ability effects were estimated to be significant (P<0.05), and the estimates were -0.1999~0.3380 for weaning weights and -0.4056~0.3317 for body weights at the age of 60 days. Reciprocal effects were found to be largest in BALB/c${\times}$C57BL and BALB/c${\times}$C3H. The estimates were -0.5049 from BALB/c${\times}$C57BL and 0.4972 from BALB/c${\times}$C3H form weaning weights, and -1.0336 from BALB/c${\times}$C57BL and 1.2793 from BALB/c${\times}$C3H for body weights at the age of 60 days.