• 한국작물학회지
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• 제34권3호
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• pp.239-245
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• 1989

벼의 Source와 Sink 관련형질의 동일주내 개체간 변이 및 상호관련성을 알기 위하여 조만성이 다른 6개벼 품종의 지상부 생육제특성을 조사, 분석하였던 바 다음과 같은 결과를 얻었다. 1. 동일건재에서 개체간 제형질의 편이 및 변이는 절간장은 하위절간, 엽신은 지엽, 엽 폭은 하위엽신에서 컸고, 수에 있어서는 2차지경과 2차지경 착생영화수에서 컸다. 2. 식물체 부위별 Source와 Sink 관련기관과 영화착색수와의 관계는 영화수는 제2엽신장 및 엽면적, 제2절간장, 제3정간태에 영향을 주는 고도의 유의적인 정상관관계이었다. 3. 절위별 절간장 및 엽위별 엽신장과 수장과의 상관관계도 제2엽신장 및 2정간장에 수장이 영향을 받는 정도가 컸다. 4. 1, 2차지경수와 영화수와의 관계는 1차지경보다는 2차지경수가 많을수록 영화수도 증가하는 상관관계이었다. 5. 식물체의 무기성분조성은 엽신, 엽초, 간, 수의 순위로 높은 함량을 나타냈다.

• 생명과학회지
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• 제19권10호
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• pp.1382-1388
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• 2009

Rubus crataegifolius is a shrub species and is primarily distributed throughout Asia and Europe. We collected 550 representative samples of the eleven populations in Korea to estimate leaf variation within species. The 35 morphological characteristics allowed us to resolve well-supported fixed characteristics and variable characteristics. Sixteen of twenty-three quantitative characteristics and five of twelve qualitative characteristics showed significant differences among populations. We argued that the population differentiation can accounted for the variation in phenetic characteristics such as spine in this species, but were less successful in accounting for variation in other traits. Within a polystatistic leaf structure, their morphological differences could be modulated by ecological pressure such as temperature, altitude, duration of sunshine, and solar radiation. The phenogram showed two distinct clades. One was a group in central Korea and the other was a group in the southern regions of Korea. If morphological characteristics in R. crataegifolius populations reflect their ecological niche, morphology should be regarded with caution as the main criterion for population studies in R. crataegifolius.

• 한국연초학회지
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• 제16권1호
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• pp.43-52
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• 1994

To investigate the factors of the improvement of cultivation methods according to the plant type, three Burley tobacco cultivars were done. Experiments on the variability of plant type and factors representing the productivity and quality of the cultivar were subsequently carried out in relation to different fertilizer levels. Results are summarized as below. Use of more fertilizer resulted in higher plant height and longer leaf length but smaller mean leaf inclination(MLI). The horizontal leaf area distribution became greater in parts distal to the stem and the vertical leaf area distribution became greater in lower half than in upper half as the amount of fertilizer applied was increased. Br. 49 was the largest but Br. 21 and NTN 77 were similar with respect to both CGR and NAR. The yield was greater in larger MLI cultivars. These three characteristics became greater when the tobacco were heavier in the cultivars of larger MLI and increased with higher amount of fertilizer. Harvest index became greater as the amount of fertilizer decreased but not significantly differ among the cultivars. Total nitrogen content and nitrate - form nitrogen content were greater, more amount of fertilizer, and larger MLI cultivar plots. Total nitrogen content was higher in upper leaves. The filling power of tobacco leaves decreased but combustibility of leaves showed not significant trend as fertilizer application level increased.

• 한국연초학회지
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• 제16권1호
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• pp.34-42
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• 1994

Experiments on the variability of plant type and factors representing the productivity and quality of the cultivars were subsequently carried out in relation to different plant density. Results are summarized as below. The higher was the plant density, the greater was the plant height and mean leaf inclination(MLI). As the plant density increased, the horizontal leaf area distribution became greater in proximal to the stem in NTN 77 and Br.49 but evenly in distal part in Br.21. Meanwhile, in terms of vertical leaf area distribution, it was decreased much more in middle and lower leaves than in upper in NTN 77 and Br.49 although it steadily decreased in any part of the plant in Br.21. Br.49 was the largest but Br.21 and NTN 77 were similar with respect to both CGR and NAR. The yield was greater in larger MLI cultivars(NTN 77>Br.49>Br.21). These three characteristics became greater when the tobacco were planted more densely in the field. Dry leaf weight and dry matter weight per plant were heavier in the larger MLI and increased with lower plant density. Total nitrogen content was greater in lower plant density and larger MLI cultivar. The plant density increases filling power seems to be enhanced regardless to the plant type. There was no discernible tendency on combustibility according to the plant density or plant type.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.25-28
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• 2002

The aim of the present study was the evaluation of methods for estimating the vegetation information in the field on the basis of spectral reflectance measured farm field, in particular the estimation of Leaf Area Index(LAI). Variability in tissue optical properties was wavelength-dependent. For rice and bean, the lowest variation was in the visible spectral region and the highest in the near-infrared. The structural attributes of ecosystems determine the relative contribution of tissue and canopy factors that drive variation in a reflectance signal.

• Journal of Plant Biology
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• 제5권1호
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• pp.1-6
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• 1962

1) Germination rate was rather irregular than decreasing as increasing dose of radiation and there were no differences between Kyong-Sam and Chuong-Bang of Chinese cabbage. 2) In R1 generation, abnormal leaves from seedling of irradiated seeds were observed. These were more apparent in X-ray irradiation than in thermal neutron. 3) Seedling height was inhibited with increasing dose of X-ray and thermal neutrons. Growth inhibition was more remarkable in X-ray than in thermal neutron. Kyong-Sam demonstrated more sensitivity than Chyong-Bang in both X-ray and thermal neutron. 4) Seedling height produced from seeds subjected to thermal neutrons showed small variation around its mean value, while in X-irradiation there was a greater deviaton from the mean value. 5) Fertility was decreased as increasing with dose, while the frequency of abortive pollen was increased. There were variability of the fertility and frequency of abortive pollen among plants or branches of a plant. 6) The mutants were obtained more in thermal neutron irradiation than in X-ray. The types of mutations obtained in Chinese radish of R2 generation were abnormal leaf, densely glowing leaf, degeneration in growing point and dwarf. The maximum frequency of phenotypic mutations was abnormal leaf mutation.

• 한국환경과학회지
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• 제33권7호
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• pp.501-509
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• 2024

Prunus mume is a culturally significant fruit tree in East Asia that is widely used in traditional foods and medicines. The present study investigated the effects of sunlight exposure and leaf position on the photosynthetic efficiency of P. mume using SPAD values. The study was conducted at Cheongju National University of Education, Korea, under contrasting conditions between sunny (Site A) and shaded (Site B) areas on P. mume trees. Over three days, under varied weather, photosynthetic photon flux density (PPFD) and SPAD measurements were collected using a SPAD-502 plus chlorophyll meter and a smartphone PPFD meter application. The SPAD values of the 60 leaves were measured in triplicate for each tree. The results indicated that trees in sunny locations consistently exhibited higher SPAD values than those in shaded areas, implying greater photosynthetic efficiency. Moreover, leaves positioned higher in the canopy showed increased photosynthetic efficiency under different light conditions, underscoring the significance of leaf placement and light environment in photosynthetic optimization. Despite the daily sunlight variability, these factors maintained a consistent influence on SPAD values. This study concludes that optimal leaf positioning, influenced by direct sunlight exposure, significantly enhances photosynthetic efficiency in P. mume. These findings highlight the potential of integrating smart farming techniques, especially open-field smart farming technology, to improve photosynthesis and, consequently, crop yield and efficiency. The findings also highlight the need for further exploration of environmental factors affecting photosynthesis for agricultural advancement.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.246-253
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• 2019

Background: Water use efficiency (WUE) is an indicator of the trade-off between carbon uptake and water loss to the atmosphere at the plant or ecosystem level. Understanding temporal dynamics and the response of WUE to climatic variability is an essential part of land degradation assessments in water-limited dryland regions. Alternative definitions of and/or alternative methodologies used to measure WUE, however, have hampered intercomparisons among previous studies of different biomes and regions. The present study aims to clarify semantic differences among WUE parameters applied in previous studies and summarize these parameters in terms of their definition and methodology. Additionally, the consistency of the responses of alternative WUE parameters to interannual changes in moisture levels in Northeast Asia dryland regions (NADRs) was tested. Results: The literature review identified more than five different WUE parameters defined at leaf and ecosystem levels and indicates that major conclusions regarding the WUE response to climatic variability were partly inconsistent depending on the parameters used. Our demonstration of WUE in NADR again confirmed regional inconsistencies and further showed that inconsistencies were more distinct in hyper- and semi-arid climates than in arid climates, which might reflect the different relative roles of physical and biological processes in the coupled carbon-water process. Conclusions: The responses of alternative WUE parameters to drying and wetting may be different in different regions, and regionally different response seems to be related to aridity, which determines vegetation coverage.

• Plant Biotechnology Reports
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• 제2권3호
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• pp.191-198
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• 2008

Germplasm characterization and evolutionary process in viable populations are important links between the conservation and utilization of plant genetic resources. Here, an investigation is made, based on molecular and biochemical techniques for assessing and exploiting the genetic variability in germplasm characterization of taro, which would be useful in plant breeding and ex situ conservation of taro plant genetic resources. Geographical differentiation and phylogenetic relationships of Indian taro, Colocasia esculenta (L.) Schott, were analyzed by random amplified polymorphic DNA (RAPD) and isozyme of seven enzyme systems with specific reference to the Muktakeshi accession, which has been to be proved resistant to taro leaf blight caused by P. colocasiae. The significant differentiations in Indian taro cultivars were clearly demonstrated by RAPD and isozyme analysis. RAPD markers showed higher values for genetic differentiation among taro cultivars and lower coefficient of variation than those obtained from isozymes. Genetic differentiation was evident in the taro accessions collected from different regions of India. It appears that when taro cultivation was introduced to a new area, only a small fraction of genetic variability in heterogeneous taro populations was transferred, possibly causing random differentiation among locally adapted taro populations. The selected primers will be useful for future genetic analysis and provide taro breeders with a genetic basis for selection of parents for crop improvement. Polymorphic markers identified in the DNA fingerprinting study will be useful for screening a segregating population, which is being generated in our laboratory aimed at developing a taro genetic linkage map.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.144.2-145
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• 2003

This study was performed to investigate the incidence of Hosta uirus X (HVX), a Potexvirus, from cultivated hosta ornamental plants in Korea and to ascertain seed transmission of the virus from infected parent plant to progeny ones for breeding program of hosta plants. Infection rate of HVX in cultivated hostas was 25.6 ％ (11 out of 43 collected samples contained HVX) based on Western blot and RT-PCR detection methods. Most of HVX-infected hostas showed visible systemic leaf symptoms (mosaic, mottle, curling, stunting or combinations). Variability of HVX was confirmed by sequences of coat protein gene of individual isolates from different hostas. HVX was seed-transmitted on Hosta 'Blue Cadet'. The virus was detected from seeds, and sprouts and seedlings from the virus-contaminated seed sources. Over 7.5 ％ of seeds were HVX-contaminated surveyed in this study, Our data suggest that HVX can be transmitted by seed source, and indexing of the virus should be done for breeding program of Hosta.