• 한국자원식물학회지
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• 제12권2호
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• pp.152-160
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• 1999

1. 콩잎의 세균밀도는 4.60$\times$$10^2$~ 9.10$\times$$10^{5}$CFU/$\textrm{cm}^2$으로, 생육단계가 진전됨에 따라 세균밀도가 증가하는 경향이었다. 2. 콩나물 부패 세균의 밀도는 콩잎에서 0~5.00$\times$$10^3$CFU/$\textrm{cm}^2$으로, 부패세균의 밀도는 생육단계에 관련이 없었으나 재배지역과는 관련이 있었다. 3. 나물 콩 품종과 콩나물 부패세균의 밀도는 품종과 관련이 적었으며 생육단계와 작물의 부위에 따라 변이가 심하였다. 4. 콩잎에서 분리된 콩나물 부패세균은 Erwinia cypripedii, E. carotovora subsp. carotovora, Xanthomonas campestris pv. glycines, Staphylococcus sp., Micrococcus sp. 이며, E. carotovora subsp. carotovora, X. campestris pv. glycines가 밀도가 높았다.다.

• 한국작물학회지
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• 제48권2호
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• pp.96-102
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• 2003

This study was conducted to determine the effects of two plant populations (28 and 14 plants per $m^2$) and two toppings in conventional plant population (28 plants per $m^2$) on soybean (Glycine max L. cv. Pungsannamulkong) cultivated in the paddy field. The two topping time were taken at 6$^{th}$ to 7$^{th}$ and 8$^{th}$ to 9$^{th}$ trifoliolate leaf stages in the conventional plant population. Experimental design for growth data was a randomized complete block with three replications, and samples were taken at R1 (July 31), R3 (August 19), R5 (September 2) and R7 (September 23) growth stages. The branch number of soybean was relatively higher in the low plant population (14 plants per $m^2$) and with the topping at the 6$^{th}$ to 7$^{th}$ leaf stage, in the conventional plant population (28 plants per $m^2$), and with topping at the 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage in descending order. The highest average branch length of soybean was observed in the low population and the longest branch length was observed from the soybean with topping at the 6$^{th}$ to 7$^{th}$ leaf stage. The leaf number per plant was decreased in order of in the low population, with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage, with the topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage, and in the conventional population. The leaf area was high in the low population and with topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with the topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage in soybean. The dry weight of leaves and branches was high in the low population and with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage. The leaf number per plant was high in the low population and with topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage and was relatively low in the conventional population and with topping at 8$^{th}$ to 9$^{th}$ trifoliolate leaf stage. The grain yield per 10a was high with the topping at 6$^{th}$ to 7$^{th}$ trifoliolate leaf stage.

• Journal of Plant Biology
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• 제30권4호
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• pp.299-309
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• 1987

The seasonal pattern and the annual magnitude of the internal (or biochemical) and plant-soil cycles of phophorus in adjacent three different herb plant populations-Helianthus tuberosus L., Artemisia princeps Pampan and Phalaris anundinacea L.-in an old field of the basin in the Mt. Geumoh were investigated. A lot of the phosphorus demand for the three populations was supplied by the withdrawal from below-ground organ in early growing period, by the absorption from soil in mid-growing period and by the withdrawal from stem in later growing period. But in the A. princeps and P. arundianacea populations, a great deal of phosphorus seemed to be absorbed prior to the first withdrawal. The annual amount of the phosphorus flowing throughthe internal cycle was about 59% of the total hosphorus flow on theorgan level in the H. tuberosus population, 41% in the A. princeps population and 32% in the P. arundinacea population, indicating that the tuber plant had the most developed internal cycle system. The annual amount of phosphorus which took part in the plant-soil cycle in the stand of the three populations was in the range of 4.49-5.65 gPm-2, corresponding to only 3-8% of the extractable phosphorus contained in the soil of 0-20 cm depth. The fact that the H. tuberosus population is higher in the extent fo internal cycle but smaller in the magnitude of plant-soil cycle and lower in the turnover rate of phsophorus than the other two populations suggests that the growth of H. tuberosus population may be less dependent on soil phosphorus availability than those of the other two populations.

• The Plant Pathology Journal
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• 제29권4호
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• pp.435-439
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• 2013

Rice blast fungus, Magnaporthe oryzae, inflicts serious damage to global rice production. Due to high variability of this fungal pathogen, resistance of newly-released rice cultivars is easily broken down. To understand the population structure of M. oryzae, we analyzed the genetic diversity of the Korean population using multilocus microsatellite typing. Eleven microsatellite markers were applied to the population of 190 rice isolates which had been collected in Korea for two decades since the 1980's. Average values of gene diversity and allele frequency were 0.412 and 6.5, respectively. Comparative analysis of the digitized allele information revealed that the Korean population exhibited a similar level of allele diversity to the integrated diversity of the world populations, suggesting a particularly high diversity of the Korean population. Therefore, these microsatellite markers and the comprehensive collection of field isolates will be useful genetic resources to identify the genetic diversity of M. oryzae population.

• The Plant Pathology Journal
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• 제21권1호
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• pp.64-67
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• 2005

The biocontrol agent Serratia plymuthica A21-4 readily colonized on the root of pepper plant and the bacterium moves to newly emerging roots continuously. The colonization of A21-4 on the pepper root was influenced by the presence ofPhytophthora capsici in the soil. When P. capsici was introduced in advance, the population density of A21-4 on the root of pepper plant was sustained more than $10^6$ cfu/g root until 3 weeks after transplanting. On the other hand, in the absence of P. capsici, the population density of A21-4 was reduced continuously and less than $10^5$ cfu/g root at 21 days after transplanting. S. plymuthica A21-4 inhibited successfully the P. capsici population in pepper root and rhizosphere soil. In the rhizosphere soil, the population density of P. capsici was not increased more than original inoculum density when A21-4 was treated, but it increased rapidly in non-treated control. Similarly, the population density of P. capsici sharply increased in the non-treated control, however the population of P. capsici in A21-4 treated plant was not increased in pepper roots. The incidence of Phytophthora blight on pepper treated with A21-4 was 12.6%, while that of non-treated pepper was 74.5% in GSNU experimental farm experiment. And in farmer's vinyl house experiment, the incidence of the disease treated with the fungicide was 27.3%, but treatment of A21-4 resulted in only 4.7% of the disease incidence, showing above 80% disease control efficacy.

• 한국어류학회지
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• 제35권4호
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• pp.217-223
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• 2023

잔가시고기 Pungitius kaibarae의 신규 집단인 고령(GR) 집단과 야생 집단의 특성을 규명하기 위해 미토콘드리아 cytb 유전자 영역의 886 bp 서열을 이용 총 4개 집단 (경상북도 고령(회천, GR), 포항(곡강천, PH), 경산(오목천, GYSA), 강원도 고성(배봉천, GS))을 분석하였다. 고령(GR) 집단에서 가장 낮은 haplotype 다양성을 나타냈고(H_d=0.000), 고성(GS) 집단에서 0.755로 가장 높은 haplotype 다양성을 확인하였다. Nucleotide 다양성은 고성(GS) 집단에서 0.00291로 가장 높은 다양성을 나타냈으며, 고령(GR) 집단에서 가장 0.00000로 가장 낮은 다양성을 보였다. 유전적 분화도에서 고령(GR) 집단은 포항(PH) 집단과 유전적으로 가장 가까운 것으로 나타났다. Haplotype 네트워크는 고령 (GR) 집단이 포항(PH) 집단과 군집되어 가장 유사한 것으로 나타났다. 고령(GR) 집단은 계통발생학적 tree에서 높은 지지도(98%)의 값으로 포항(PH) 집단과 군집됨을 확인하였다. 따라서 고령(GR) 집단은 포항(PH) 집단과 유사한 집단에서 유래됨을 추정하였다.

• Journal of Plant Biotechnology
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• 제50권
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• pp.207-214
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• 2023

Lindera obtusiloba (Lauraceae) is a dioecious tree that is widely distributed in the low-altitude montane forests of East Asia, including Korea. Despite its various pharmacological properties and ornamental value, the genetic diversity and population structure of this species in Korea have not been explored. In this study, we selected 6 nuclear and 6 chloroplast microsatellite markers with polymorphism or clean cross-amplification and used these markers to perform genetic diversity and population structure analyses of L. obtusiloba samples collected from 20 geographical regions. Using these 12 markers, we identified a total of 44 alleles, ranging from 1 to 8 per locus, and the average observed and expected heterozygosity values were 0.11 and 0.44, respectively. The average polymorphism information content was 0.39. Genetic relationship and population structure analyses revealed that the natural L. obtusiloba population in Korea is composed of 2 clusters, possibly due to two different plastid genotypes. The same clustering patterns have also been observed in Lindera species in mainland China and Japan.

• 한국연초학회지
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• 제3권2호
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• pp.115-122
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• 1981

Data for this study were obtained from Burley 21 (Nicotiana tabacum L.) grown under various densities on the field in 1978 and 1979 at the Jeonju Experiment Station, Korea Ginseng & Tobacco Research Institute. Interrelations between yield and its components were statistically studied by correlation, regression, and pathway analysis. Correlation of yield with plant population was significant and positive. Quadratic functions for yield vs. plant population and the length of the largest leaf were fitted to the data. Multiple recession equation between yield and its components (leaf number ($X_1$), a leaf area ($X_5$), weight per unit leaf area ($X_9$), plant population ($X_14$)), was significant at the 5% level. Measuring the relative importance of its components on yield, plant population was 49.5%, weight per unit leaf area 25.3%, a leaf 15.6%, and leaf number 9.8%.

• 한국작물학회지
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• 제35권2호
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• pp.117-121
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• 1990

단옥수수의 수량을 상품성 있는 이삭수, 이삭무게, 이삭크기별 시장가격을 적용한 조수입으로 평가하였을 때 이들 수량평가방법의 결과를 비교하기 위하여 단옥수수 품종 Golden Cross Bantam 70을 재식밀도(5,000, 6,000, 7,000, 8,000, 9,000주/10a)를 달리하여 0.3mm 투명 P.E. film 피복하에서 재배하였다. 출아후 30일과 44일에 초장과 분벽수를 조사하였고, 이삭조사는 출사후 25일에 수확하여 포엽을 제거한 후 이삭의 수, 크기, 무게를 조사하고 무게별 이삭수, 10a당 상품성 있는 이삭수, 이삭무게 조수입을 계산한다. 1. 초장, 간장, 착수고, 분벽수, 출사기는 재식밀도간에 차이가 없었으며, 수확기의 주간 엽면적지수는 1.1-1.9로서 재식밀도가 높을수록 증가하였다. 2. 상품성있는 이삭의 평균길이, 굵기, 무게와 포엽을 제거한 이삭무게가 150g 이상인 상품의 비율은 재식밀도가 높을수록 감소하였다. 3. 10a당 상품성있는 이삭수, 이삭무게 및 크기별 가격과 이삭수를 고려한 조수입은 재식밀도가 높을수록 증가하였으며, 이들간에는 고도로 유의한 정의 상관이있었다. 재식밀도가 높을때는 이삭수는 조수입보다 과대평가되었고, 이삭무게는 과소평가되었다. 4. 이삭을 수확한 후 경엽의 건물수량은 755-964kg/10a으로 7,000주/10a까지는 재식밀도가 높을수록 증가하였으며 건물함량은 20.7-24.5%이었다. 5. 흑조위축병 리병율은 10.6-15.0%이었으나 재식밀도간에는 차이가 없었다.

• The Plant Pathology Journal
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• 제34권5호
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• pp.393-402
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• 2018

Rice world production is affected due to the growing impact of diseases such as bacterial panicle blight, produced by Burkholderia glumae. The pathogen-induced symptoms include seedling rot, grain rot and leafsheath browning in rice plants. It is currently recognized the entrance of this pathogen to the plant, from infected seeds and from environmental sources of the microorganism. However, it is still not fully elucidated the dynamics and permanence of the pathogen in the plant, from its entry until the development of disease symptoms in seedlings or panicles. In this work it was evaluated the infection of B. glumae rice plants, starting from inoculated seeds and substrates, and its subsequent monitoring after infection. Various organs of the plant during the vegetative stage and until the beginning of the reproductive stage, were evaluated. In both inoculation models, the bacteria was maintained in the plant as an endophyte between $1{\times}10^1$ and $1{\times}10^5cfu$ of B. $glumae.g^{-1}$ of plant throughout the vegetative stage. An increase of bacterial population towards initiation of the panicle was observed, and in the maturity of the grain, an endophyte population was identified in the flag leaf at $1{\times}10^6cfu$ of B. $glumae.g^{-1}$ fresh weight of rice plant, conducting towards the symptoms of bacterial panicle blight. The results found, suggest that B. glumae in rice plants developed from infected seeds or from the substrate, can colonize seedlings, establishing and maintaining a bacterial population over time, using rice plants as habitat to survive endophyticly until formation of bacterial panicle blight symptoms.