• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.46-53
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf, stem, grain, root and rhizosphere soil sainples of four rice cultivars collected from three regions of Korea. Thirty five pigmented and five non-pigmented isolates showing characteristic growth on methanul were obtained. When phylotypes were defined by performing numerical analysis of 42 characteristics, four distinct clusters were formed. While two clusters, I and IV diverged on the basis of nitrate and nitrite reduction, other two clusters, comprising only pink pigmented colonies, diverged on the basis of cellulase activity. Out of the two reference strains used in the analysis, Methyhbacterium extorquens AM1 diverged from all the clusters and M. fujisawaense KACC 10744 grouped under cluster III. All the isolates were positive for urease, oxidase, catalase and pectinase activity and negative for indole production, MR and VP test, $H_2S$ production, starch, and casein hydrolysis. No clusters were found to possess thermotolerant isolates, as no growth of the isolates was observed at $45^{\circ}C$. Two strains in cluster I were found to possess gelatin hydrolysis and methane utilizing properties respectively. Most of the isolates in all the four clusters utilized monosaccliarides, disaccharide and polyols as carbon source. Six isolates showed considerable nitrogenase activity ranging from 86.2 to $809.9nmol\;C_2H_4\;h^{-1}\;mg^{-1}$ protein.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.651-654
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• 2011

Cymbidium 'Orange Bowl' (Lucky Rainbow 'Randevous' ${\times}$ 'Eastern Star') was developed from a cross between hybrids at the National Institute of Horticultural & Herbal Science, Rural Development Administration in 2006. A cross was made between the pink colored flower C. Lucky Rainbow 'Randevous' as maternal line and pure yellow colored flower, C. 'Eastern Star' as paternal line in 1995. The seed germination, cultivation, selection, and characteristic trials were conducted from 1996 to 2006. The line was named as Wongyo F1-18 and phenotype was characterized in 2006 as a new 'Orange Bowl'. The 'Orange Bowl' has having light yellow basal color (RHS, YO21D) and orange line (RHS, OR30B) on both of sepal and petal with red lip (RHS, OR30B). 'Orange Bowl' has about 10.9 flowers per flower stalk and flower size of 7.4 cm. General appearance of the petals and sepals is slightly incurved shape. The plant size is intermediate having erect peduncle. Blooming is started from the late of January (mid winter) under optimal culture condition. Leaf attitude and twisting is half- erect and very weak respectively. This hybrid has attractive floral arrangement, long flower stalk (71.8 cm) and vigorous growth. We expect that 'Orange bowl' has a great potential for exporting to Chinese market.

• Korean journal of applied entomology
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• v.55 no.3
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• pp.235-243
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• 2016

The winter cherry bug, Acanthocoris sordidus (Thunberg), is an insect pest hat damages plants from Solanaceae and Convolvulaceae. The developmental period from egg to adult averages 76 days at $25^{\circ}C$. Adult egg-laying occurred irregularly via spawning, averaging 195 (up to 468) eggs per individual on the abaxial leaf surface of the host plant. Results of linear regression indicated that the lower developmental threshold temperature was $13.9^{\circ}C$ and the effective accumulated temperature was 526.3 DD. Data from a pepper field in 2015 indicated that overwintering adults first appeared during late June (daily average temperature = $25.7^{\circ}C$), reaching maximum density by early September. A choice test examining colonization preferences using a net cage and a Y-tube olfactometer revealed that females gravitated toward conspecifics (other females, males, or both), whereas males moved toward empty areas. Finally, we found that communal breeding results in a longer developmental period and higher eclosion rates than solitary breeding. Developmental periods and eclosion rates were also for colonies in a large space than for those in a small space. This outcome suggests that colonization effects on insect development are stronger in a smaller area.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.618-623
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• 2015

The new white calla lily (Zantedeschia aethiopica) cultivar 'White Cutie' was bred at the National Institute of Horticultural & Herbal Science (NIHHS) in 2011. 'Childsiana' showing the multi-flowering characteristic and 'Wedding March' resistant to soft rot disease were artificially crossed in 2004. Of the progeny, 'White Cutie' was selected specifically for use in cut flower production after investigation over seven years (2005 to 2011) of genetic and phenotypic characteristics, resistance against soft rot, and customer preference regarding the culture vigor and post-harvest quality. 'White Cutie' was early flowering (85.6 days to flowering) with white flowers (RHS W155C), although it had a mid-sized flower in which spathe height and width were 8.6 cm and 8.7 cm, respectively. It was multi-flowering (6.2 flowers per plant) and produced a very high number of cormels (13.4 per plant). Furthermore, it was resistant to soft rot disease.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.334-337
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• 2012

A new promising kiwifruit, 'Halla Gold' variety with yellow flesh and being harvested in October, was developed at the Agricultural Research Center for Climate Change, National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea in 2007. This variety was derived from the seedling population crossed between Actinidia chinensis cv. Golden Yellow and A. chinensis cv. Songongu in 1997. It was selected out of 2,971 seedlings. Characteristic trials were carried out from 2001 to 2003. After the selection, adaptability test was also conducted at kiwifruit orchards in Jeju Island from 2003 to 2007. Shoots of 'Halla Gold' sprout slightly stronger than those of 'Jecy Gold' but weaker than 'Hort16A' and the color of leaf is green. Fruit shape is oblong and fruit skin color is yellowish-dark green without hair. The average weight of fruit is 106.3 g. Fruit has a moderate size soft core, yellow pericarp, and fragile and juicy flesh. Soluble solids content is $14.7^{\circ}$ Brix and acidity is 1.4%. The harvesting time is about 10 days earlier than 'Jecy Gold' and about 20 days ahead of 'Hort16A'. The storage life is about 90 days at $2^{\circ}C$. This variety can be recommended for cultivating at low land area bellow 100 m sea level in Jeju Island or under shelter to prevent disease and cold injury.

• Research in Plant Disease
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• v.13 no.1
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• pp.45-49
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• 2007

Single spores were isolated from infected roots of Chinese cabbage with a typical clubroot symptom, collected from different Chinese cabbage cultivation areas in Korea. When the single spore isolates were inoculated on Chinese cabbage, radish, turnip, kale, leaf mustard and Williams' differential varieties, among 321 roots harvested two weeks after inoculation, a visual symptom was observed on only one root and light/uncommon symptoms were done on 70 roots. These 71 individuals were homogenized and used as inocula. These inocula caused generally higher pathogenicity than that of single spore. Finally 15 isolates, with enough growth for conducting further experiment, were selected. These 15 individuals were grouped four, seven, two and two into race 1, race 4, race 9 and race 11, respectively, using Williams' differential set. It was confirmed that race 4 were dominantly present in Korea. These 15 had been obtained from roots of Chinese cabbages, radishes and turnips inoculated with single resting spores and had shown pathogenicity to Laurentian and Wilhelmsburger belong to Rutabaga in Williams' differential variety set. Therefore, we assume that such characteristic pathotypes including race 4, especially, of P. brassicae showing strong pathogenicity to Chinese cabbage, radish and turnip may be dominant in Korea.

• Weed & Turfgrass Science
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• v.6 no.3
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• pp.196-202
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• 2017

This study was conducted to investigate the change of yield and quality according to seeding time and planting density and to determine effective weed control method in wet-hill-seeding use black colored rice. The most effective weed control system was application of bromobutide thiobencarb five days before seeding followed by bensulfuron mefenacet thiobencarb 12 days after seeding (barnyardgrass at 2.5-3.0 leaf stage). The seedling stand by seeding time and planting density increased with the delay seeding time and high planting density. The heading dates were delayed as the seeding time became late but no difference was found between planting density. The anthocyanin content of black colored rice was higher at late seeding time and lower planting density. The yield of full colored rice was high 80 plants per $3.3m^2$ in seeding on May 30 and June 10. This information could be useful for spreading rice direct seeding by inducing stabilization of wet-hill-seeding use black colored rice.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.658-662
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• 2007

In this study, wild sesame leaf aromas (WSLA) were extracted and the extracted aromas were entrapped in porous potato starch micelles. The entrapped aromas did not evaporate, even by heated water treatments, and remained until a physical treatment such as chewing. Thus, the entrapped WSLA starch was used to make precooked instant noodles in order to mask or/and reduce an unpleasant raw flour flavor. The efficiencies of the flavor entrapment were analyzed using gas-chromatography equipped with solid phase micro-extraction (SPME), as well as by sensory evaluation. The highest yield of the porous potato starch was shown as 82.4% at an inlet temperature (IT) of $170^{\circ}C$, an exhaust temperature (ET) of $90^{\circ}C$, and a feeding rate (FR) of 40 mL/min. In the porous starch made by IT at $200^{\circ}C$, ET at $100^{\circ}C$, and FR at 50 mL/min, the entrapment efficiency was 68% by GC analysis; this starch also had the highest WSLA and consumer acceptability, but the lowest raw flour flavor, according to the sensory evaluation results.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.96-104
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• 2010

A comparative study was performed in gnotobiotic and greenhouse conditions to evaluate the effect of exogenous application of indole-3-acetic acid (IAA) and inoculation of Methylobacterium spp. possessing 1-aminocyclopropane-1-carboxylate deaminase (ACCD) and IAA activity on red pepperand tomato seedling growth and development. Application of 1.0 ${\mu}g\;mL^{-1}$ IAA positively influenced root growth while high concentrations (>10.0 ${\mu}g\;mL^{-1}$) suppressed root growth of red pepper and tomato under gnotobiotic condition. On the other hand, inoculation of Methylobacterium strains with ACCD activity and IAA or without IAA enhanced root growth in both plants. Similarly, under greenhouse condition the inoculation of Methylobacterium sp. with ACCD activity and IAA enhanced plant fitness recorded as average nodal length and specific leaf weight (SLW) but the effect is comparable with the application of low concentrations of IAA. Seedling length was significantly increased by Methylobacterium strains while total biomass was enhanced by Methylobacterium spp. and exogenous applications of < 10.0 ${\mu}g\;mL^{-1}$ IAA. High concentrations of IAA retard biomass accumulation in red pepper and tomato. These results confirm that bacterial strains with plant growth promoting characters such as IAA and ACCD have characteristic effects on different aspects of growth of red pepper and tomato seedlings which is comparable or better than exogenous applications of synthetic IAA.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.223-229
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• 2003

This study was carried out to investigate the optimum ionic strength of nutrient solution were treated with a quarter, a half, three quarters, standard, one and half, and double ionic strength of balanced nutrient solution of Yamazaki solution recommended for cucumber plants. Plant height and number of loaves of growing period were rapidly increased in 1/2 ionic strength of nutrient solution. Growth characteristics of cucumber plant as affected by the different ionic strength of nutrient solution were not significant differences, however, in the growing period, plant height, stem length and leaf area were highest in 1/2 ionic strength of nutrient solution. Fruit yield of cucumber plant as affected by the different ionic strength of nutrient solution was not significant differences, however, fruit yield was highest in 1/2 ionic strength of the lowering ionic strength of nutrient solution. Nitrogen concentration was not significant differences, however, it was high corcentration in 1/2 ionic strength of nutrient solution. Growth and yield characteristic of cucumber as affected by 1/2 ionic strength of nutrient solution at 36 days transplanting analyzed correlation cofficient. Plant height showed positive correlated with number of plant and positive correlated with yield.