• Korean Journal of Environmental Biology
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• v.30 no.1
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• pp.47-53
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• 2012

To evaluate adaptation success of $Zostera$ $caespitosa$ transplants, we transplanted the seagrass shoots at the bare area in close proximity to the donor bed using staple method in October 2005. Shoot density, morphological characteristics and leaf productivity of transplants and reference plants in the vicinity of the planting site were monitored monthly for 2 years. While shoot density of reference plants exhibited significant seasonal variations; increasing during spring and summer and decreasing during fall and winter, that of transplants increased consistently without initial loss during the whole study period. Although sheath length, leaf width and shoot height and weight of sheath, leaf and shoot of transplants were smaller than those of reference plants at the start of transplantation, increased rapidly reaching even higher values than those of reference plants 5 months after transplantation. Leaf productivity of transplants and reference plants showed seasonal variations; increasing during spring and summer and decreasing during fall and winter. But, leaf productivity of transplants increased at the beginning of transplantation during fall which is low production period. All of the $Z.$ $caespitosa$ transplants survived during the whole study period. Rapid changes in shoot morphology and growth of transplants indicated that $Z.$ $caespitosa$ transplants had great morphological plasticity and adapted successfully within 5 months.

• Korean Journal of Ecology and Environment
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• v.46 no.4
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• pp.513-523
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• 2013

This ecological study was conducted to analyze seasonal variation characteristics of Zostera marina at HAENAM SAGUMI on the Southern Coast of Korea. Environmental characteristics, plant morphological characteristics, shoot density, biomass, and leaf production were monitored from August 2008 to March 2011. Zostera marina occurred in the subtidal zone from 0 to 2.5 m below the mean low water level. Water temperature showed a clear annual pattern, with increase in spring and summer, and decreases in fall and winter. Irradiance showed seasonal variation, even though daily weather condition has short-term variation in the incident irradiation. Plant morphological characteristics, shoot density, biomass, and leaf production showed clear seasonal variation. Seasonal variation in the above biomass of Zostera marina was mainly caused by changes in shoot length. We found that there are correlations between environmental characteristics (water temperature, irradiation) and the growth of Zostera marina. There is stronger correlation between water temperature and the growth of Zostera marina, compared to the correlation between irradiation and the growth of Zostera marina. In particular, the growth of Zostera marina is inhibited by both higher and lower water temperature.

• Research in Plant Disease
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• v.22 no.4
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• pp.217-226
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• 2016

Seasonal prevalence of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) was investigated at a naturally infected orchard in Boseong, Jeonnam in 2014 and 2015. Stem canker began to occur in mid-February in 2014 and early March in 2015. Bacterial ooze was observed on canes, leaders and trunks until late May and gradually disappeared thereafter. The percentages of infected trees were 44.7% and 69.7% in 2014 and 2015, respectively. Trees with trunk canker in a previous year died in 2015. Leaf canker symptoms began to appear as brown spots with chlorotic halos in early May and irregular dark brown spots without halos were observed under humid conditions. Leaf canker progressed until mid-July in 2014 and late July in 2015. No Psa was detected from the leaf lesions on leaves thereafter, but new infection of Psa was observed on leaves in late October. Infected blossoms with blighted calyx were sometimes observed from mid-May. Optimal monitoring period to detect Psa was May when it could be easily detected from stems, leaves and blossoms. Disease cycle of bacterial canker of kiwifruit modified for Korea was proposed based on the seasonal prevalence of bacterial canker analyzed according to weather data in Boseong, Jeonnam over 2 years.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.20-23
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• 1994

The contents of ginkgolides were determined in the leaves of male and female Ginkgo biloba from late spring until mid-autumn. Ginkgolides were detected during the whole growing season in the leaves of each tree. Ginkgolides content was low in late spring, gradually increased to reach a maximum in august and decreased thereafter. The male trees have two or three times higher ginkgolides content than the female trees. Comparing our results with that of previously reported values, the sexual variation of ginkgolides content seemed not to be genetic.

• Korean Journal of Microbiology
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• v.41 no.2
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• pp.99-104
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• 2005

Corynebacterial clones which exert regulatory effects on the expression of the glyoxylate bypass genes were isolated using a reporter plasmid carrying the enteric lacZ fused to the aceB promoter of Corynebacterium glutamicum. Some clones carried common fragments as turned out by DNA mapping technique. Subcloning analysis followed by the measurement of $\beta-galactosidase$ activity in Escherichia coli identified the region responsible for the aceB-repressing activity. Sequence analysis of the DNA fragment identified two independent ORFs of ORF1 and ORF2. Among them, ORF2 was turned out to be responsible for the aceB-repressing activity. ORF1 encoded a 23,216 Da protein composed of 206 amino acids. Sequence similarity search indicated that the ORF may encode a ECF-type $\sigma$ factor and designated sigH. To identify the function of sigH, C. glutamicum sigH mutant was constructed by gene disruption technique and the sigH mutant showed growth retardation as compared to the wild type strain. In addition, the mutant strain showed sensitivity to oxidative-stress generating agent plumbagin. This result imply that sigH is probably involved in the stress response occurring during normal cell growth.

• Journal of Plant Biology
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• v.35 no.4
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• pp.317-322
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• 1992

The nitrogen fixation activity and environmental factors of Lespedeza bicli!oy Turcz, forming annual root nodules by symbiotic Rhizobium sp. were analyzed in the field conditions during the growing period. Seasunal changes of $N_2-fixation$ activity showed the maximum value of $120\;\mu\textrm{M}\;C_2_H4{\cdot}noduie\;g\;fw^{-1}{\cdot}hr^{-1}$ during the active growing period (June) and varied significantly depending on the growth phase and environmental factors. The maximum activities were attained at the conditions of pH 7, $30^{\circ}C$ of temperature, 18 Kpa of oxygen partial pressure and inhibited by water stress and nitrogen sources. The habitat soil was weak acidic and poor in nitrogen, phosphorus and organic matter contents. The leaf area ratios and chlorophyll contents were ranged from 442 to $48;\textrm{cm}^2{\cdot}g\;dw^{-1}$ and from 33 to $38\;\mu\textrm{g}\;chI{\cdot}\textrm{cm}^2$. Nitrogen contents in each organ showed the maximum of 46, 19 and $11\;mg{\cdot}g\;dw^{-1}, respectively for leaf, rool and stem in the early period. The highest phosphorus contents were 4.2, 1.2 and $0.6\;mg{\cdot}g\;dw^{-1}$, respectively for leaf. root and stem in early growing period. The allocation ratios of nitrogen quantity showed 60% for leaves and 73% for roots during the active and late growth period, and 22% [or stems in average. The allocalion ralios o[ phosphorus quantity showed 58% for leaves during the most productive period, 70% for roots in the pre-growth stage and 26% for stems in average.verage.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.634-641
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• 2014

In order to elucidate the ecological and phenological responses of bean under global warming situation, we investigated leafing and flowering phenomena and growth traits of Baktae and Seomoktae in control plot (ambient $CO_2$ concentration and temperature) and warmed plot (elevated $CO_2$ concentration and increased temperature than control) in green house. Average $CO_2$ concentration and temperature were set 540 ppm in treatment and higher $2.2^{\circ}C$ in treatment than control. The appearance of leaf unfolding and the initiation of blooming and fruit maturing in Seomoktae were late in treatment than control. In case of Baktae, the number of total pods and seeds per plant in treatment was fewer than that in control. For Seomoktae, the number of total pods per plant and weight of total seeds per plant were decreased in treatment than in control. Thus, the number of pods and seeds of Baktae declined and the production of Seomoktae was decreased under global warming condition. This result indicates that site selection and crop yield for cultivating of the bean may be changed into new area due to global warming condition.

• Korean Journal of Microbiology
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• v.33 no.4
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• pp.262-266
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• 1997

Total, direct viable count, and acid-tolerant epiphytic bacterial population sizes were quantified on leaves of chestnut tree (Castanea crenata S. et Z.) near Taejon Industrial Estate affected by acid precipitation and deposition as well as in the clean natural forest area, Mt. Kyejok, in Taejon city from August 1996 to August 1997. Geometric mean numbers of total, direct viable count, and acid-tolerant epiphytic bacteria were $9.9{\times}10^5cell/cm^2$, $1.6{\times}10^6cell/cm^2$, and $7.1{\times}10^3cfu/cm^2$ respectively, being 1.5, 2, and 2.6 times those in the clean area. Acid-tolerant epiphytic bacterial numbers at pH 5.6 by MPN method were $3.3{\times}10^4$ in the industrial area, about the same as the number, $3.4{\times}10^4MPN/cm^2$, of the clean area. Acid-tolerant bacterial number at pH 4.0 was $1.9{\times}10^{-1}MPN/cm^2$ in the industrial area, whereas none was detected in the clean area. Acid-tolerant bacteria at pH 3.0 were not detected at all in the industrial area as well as in the clean area. Epiphytic bacterial population sizes were generally the greatest in May when leaves are emerged and grew hut the lowest in November when defoliation occurs. These results showed that air pollutant deposition on leaves did not cause a decrease of epiphytic bacteria at least and acid deposition on leaves did cause an increase of acid-tolerant bacteria.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.269-277
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• 2011

Recent outbreak of new diseases and pests which were introduced from abroad, seriously hampered both quality and safety of paprika fruits. This study has been carried out to aid an establishment of guideline for safe use of pesticides and reduction of their residues on paprika. Systemic fungicides boscalid and pyraclostrobin of either mixed (a.i.; 13.6+6.8%) or single (a.i.; 47 and 18.8%, respectively) water dispersible granule formulation(WG) products were sprayed with recommended or double dosage on paprika grown in green house at March and June. To draw pre-harvest residue limit, residues of each fungicide were analyzed from fruits collected eight times from 18 to 1 day pre-harvest. The biological half-lives of both boscalid and pyraclostrobin in mixed formulation in March and June were slightly shorter than those of single formulation which ranged from 14.4 to 20.1 days. Residue levels of both fungicides of single formulation in fruits in June were about one lower compared to those in March. However, application of double dosage frequently exceeded MRLs from fruits grown both seasons. These results showed that residue levels on fruits persisted longer period of time, more than two weeks, and so the case applied in winter season. The dissipation of fungicides on leaves and fruits was compared. The distribution of both fungicides in leaves was 20-200 times higher than that of fruits and persisted up to 18 days of pre-harvest period at the concentration of 10-40 ${\mu}g\;g^{-1}$. This study indicated that the mixed formulation product exhibited low residues in fruits, but high and long enough to pathogen growth in leaves.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.34-42
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• 2009

This study was executed to introduce a greenhouse style "Evergreen Park" to apartment complexes to target hands-on resident participation and application rather than a mere viewing of the plants as a way to provide convenient and profitable service to residents in a year-round center of usable outside space. The four key points can be summarized as follows: first, subtropical plants are evergreen broad-leaved trees, which maintain their green during all four seasons the leaves are thick and glossy. Greenhouses geared toward these subtropical trees-mainly broad-leaved evergreen species-are in planning to introduce these unique, elegant plants to temperate regions. Residentswill not only gain an education regarding these species but will be provided with the best quality evergreens at very reasonable maintenance costs. Second, subtropical plants greenhouses introduced in apartment complexes are suggested for structures connected via underground passage as well as free-standing structures so as to make use of geothermal heating and apply to reducing sunlighting. Third, as a way to provide (1) health & relaxation(evergreens, herb garden, water space), (2) community & education (plant flea market/plant hospital, plant-related lecture(exhibition), hands-on experience program), (3) a vine garden for year-round use such festivities as a Butterfly Festival, Aroma festival, Smile Oak Nuts, Candlelight Festival and Christmas Photo Site. Lastly, it has been suggested that the operation and maintenance of these greenhouses will be both by resident council operation management and by outsourcing company operation management.