• 한국작물학회지
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• 제49권1호
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• pp.7-11
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• 2004

Alfalfa (Medicago sativa L.) plants have been reported to be autotoxic as well as allelopathic. Laboratory and greenhouse experiments through petri-dish and pot test were conducted to determine autotoxic effects of alfalfa leaf and soil extracts on the germination or early seedling growth of alfalfa, and to evaluate allelopathic effects of alfalfa leaf residues on alfalfa, barnyard grass, com, eclipta and soybean. Alfalfa seed germination was delayed depending on aqueous extract concentration, with no difference in final germination after 48 hours. Alfalfa root length was more sensitive to the autotoxic chemicals from leaf extracts than was germination or shoot length. Root growth of alfalfa was significantly inhibited at extract concentration of more than 1 g dry tissue/L (g $\textrm{L}^{-1}$). Hypocotyl growth, however, was not affected by all the concentrations of leaf extracts. Soil extracts from 4-yr-old alfalfa stand significantly reduced alfalfa root length by 66%, while soil extracts from 0,1, and 3yr-old stand stimulated root length up to 14-32% over the control. Residue incorporation with dry matters of alfalfa leaf at 100 g $\textrm{kg}^{-1}$ reduced seedling length of several crop and weed species, ranging from 53 to 87% inhibition. Addition of nutrient solution into alfalfa leaf extracts alleviated alfalfa autotoxic effect. This result indicates alfalfa leaf and soil extracts or residues could exert autotoxic as well as allelopathic substances into soil environments during and after establishment.

• 한국환경복원기술학회지
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• 제10권5호
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• pp.67-75
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• 2007

The purpose of this study was to pelletize to calendula and salvia seeds with peat moss as basic material for the efficient greening and vegetating of slopes and damaged areas. Also the pelletizing was compressed by spherical types that mixed basic fertilizer of N.;300 mg/l, P.;200 mg/l, K.;400 mg/g and plant growth regulator of A and NAA each 300PPM. Soil and soil surface seeding methods were researched to find the growing state of germination percent, germination date, germination force, length of leaf, number of leaf, width of leaf, length of plant, and etc. Comparing with controlled pelletizing, peat moss and +GA pelletizing treatments resulted in higher from two to three times as following growing states : length of leaves, number of leaves, width of leaves, length of plants, length of roots, fresh weights, and ratio of germination. Especially the two treatments above showed four more times effects than the +NNA treatment. Also their germinating date germinating force were earlier and stronger. The surface seeding method was superior to soil seeding.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.792-801
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• 1996

A thinning algorithm -based image analysis technique was developed to measure corn root lengths. The root length measurement method was evaluated by comparing thread lengths measured by the image analysis system with actual thread lengths. The length measurement method accurately estimated actual thread lengths (less than 2% calculated error). Also, a rapid root length density measurement procedure, which utilizes the above root length measurement method, was developed to estimate corn root length density without washing the roots. Root length densities estimated from the cut soil surface of core samples taken from the field were paired with the root length densities determined from washed roots from the same soil core sample. A linear relationship between these two values was expected and was found. Eliminating the root washing procedure reduces the time required for measuring corn root length density substantially.

• The Plant Pathology Journal
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• 제23권3호
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• pp.223-225
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• 2007

Many plant growth-promoting rhizobacteria (PGPRs) have been known for beneficial effects on plants including biological control of soilborne pathogens, induced systemic resistance to plant pathogens, phytohormone production, and improvement of nutrient and water uptake of plants. We developed a simple and rapid method for screening potential PGPR, especially phytohormone producing rhizobacteria, or for analyzing their functions in plant growth using cucumber seedling cuttings. Surface-sterilized cucumber seeds were grown in a plastic pot containing steamed vermiculite. After 7 days of cultivation, the upper part 2 cm in length of cucumber seedling, was cut and used as cucumber cuttings. The base of cutting stem was then dipped in a microcentrifuge tube containing 1.5ml of a bacterial suspension and incubated at $25^{\circ}C$ with a fluorescent light for 10 days. Number and length of developed adventitious roots from cucumber cuttings were examined. The seedling cuttings showed various responses to the isolates tested. Some isolates resulted in withering at the day of examination or in reduced number of roots developed. Several isolates stimulated initial development of adventitious roots showing more adventitious root hair number than that of untreated cuttings, while some isolate had more adventitious root hair number and longer adventitious roots than that of untreated control. Similar results were obtained from the trial with rose cuttings. Our results suggest that this bioassay method may provide a useful way for differentiating PGPR's functions involved in the development of root system.

• 한국작물학회지
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• 제40권2호
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• pp.175-184
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• 1995

6개 자식계통 찰옥수수에 의한 이면교배 조합(역교배 불포함)에 대하여 식물학적 특성과 이삭 관련 특성들에 대하여 조사한 것을 요약하면 다음과 같다. 1. 6개 자식계통들의 개화기, 간장, 착수고, 엽면적 및 수경의 길이는 각 계통들 간에 차이가 있었다. 특히 보성 계통의 수경길이가 24.4cm였는데 반하여 칠보 계통은 9cm에 불과하였다. 2. 6개 자식계통들의 이삭길이, 이삭직경, 100립중, 이삭속길이, 열수 및 이삭당 립수 등 역시 계통간에 큰 차이가 있었다. 특히 보성 계통은 이삭 길이가 13.4cm로 계통 중 가장 컸으나 이삭 직경과 열수와 이삭당 총 당수가 가장 낮았으며, 100립종은 가장 무거웠다. 반면 당진 계통은 이삭 길이가 9.3cm로 짧은 대신에 이삭직경이 크고, 또 열수도 비교적 많아 이삭당 당수가 282개로 가장 많았다. 3. 자식계통들의 10a당 곡실 수량을 보면 분얼을 하고 다수성인 제원 계통이 285kg으로 가장 많았다. 4. 15개 교잡종들이 자식계통 특성 가운데 개화기, 간장, 착수고, 엽면적 등은 교배조합에 따라 큰 차이를 보였다. 5. 15개 교잡종들의 이삭관련 특성을 보면 보성 계통을 양친으로 한 조합들은 이삭길이가 길었고 100립종도 무거웠다. 반면에 당진 계통의 교잡종들은 이삭길이가 짧았다. 6.풋옥수수 수량이 높았던 것은 보성 계통과 교배된 조합들 이었으나, 곡실수량에서는 당진과 교배된 조합들이었다. 7. 당진계통의 일반조합능력은 교잡종의 간장과 착수고를 낮게 하는데 효과적이었다. 8. 제원계통은 교잡종들의 분얼수를 증가시키는 방향으로 일반조합능력이 컸다. 9. 이삭의 길이, 100립종, 열수 등 이삭 관련 형질에 대한 일반조합능력 효과는 보성 계통이 컸고, 종실 수량에 대한 일반조합능력이 컸던 계통은 제원과 단양 계통이었다. 10. 이삭의 길이, 100립종 등에 대한 특수능력이 컸던 조합은 제원/칠보조합이었고, 종실 수량에 대한 특수조합능력이 컸던 계통은 보성/당진이었다.

• Plant Resources
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• 제8권2호
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• pp.91-95
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• 2005

In spring, to determine the optimal planting date and plant density of rapeseed in southern areas of Korea. $Taiwan^{\#1}$ variety for spring sowing, the highest yielding variety was grown under five different planting date and plant density. Yield components such as plant height, ear length, number of seedling stand per $m^2$, number of per ear and seed set percentage were highest at the plots with Mar. 5 of planting date and 50/20cm drilling of plant density. Yield of seed, oil, gas and 1,000 grains weight and erucic acid content were highest at the Mar. 5 of planting date and 50/20cm drilling of plant density. Judging from the results reported above, at optimum planting date and plant density of rapeseed seemed too be Mar. 5 of planting date and 50/20cm plant density in spring sowing.

• 한국자원식물학회지
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• 제23권6호
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• pp.541-549
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• 2010

The present study researched morphological characteristics and analyzed the genetic diversity by using RAPD in Calanthe species, native plant in Jeju, Korea. Twenty-six samples were selected by flower color, and 19 horticultural traits were investigated to study morphological characteristics. The C. discolor had the smallest leaf, the length and width of dorsal sepal, lateral sepal, petal, central lip, lateral lip, and flower stalk length were shortest and/or smallest except the spur and ovary length in Calanthe species, but those of Calanthe discolor for. sieboldii (Dence.) Ohwi (Calanthe discolor for. sieboldii) were the largest and/or biggest, and those of variants were the intermediate between C. discolor and C. discolor for. sieboldii, but spur length was the longest in C. discolor, the shortest in C. discolor for. sieboldii, and intermediate in the variants. Ovary length in C. discolor was shortest and C. discolor for. sieboldii and variants were similar with each other. The flower colors of C. discolor were brownish red, the value of CIE Lab was between 40 and 50. The flower color of C. discolor for. sieboldii was yellowish; the value of CIE Lab was between 110 and 130. And variants had various colors between 50 and 70 in the value of CIE Lab. After analyzing multiple band patterns of PCR products, 154 bands were selected as polymorphic RAPD markers. The analysis of Genetic distance of Calanthe species using RAPD showed that C. discolor and C. discolor for. sieboldii are more distant from each other than variants, and demonstrated the fact that genetic position of variants is between the other two species.

• 한국약용작물학회지
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• 제11권4호
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• pp.311-315
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• 2003

This study was carried out to compare chromosomal characteristics between Atractylodes japonica and A macrocephala. Cytogenetic analysis was conducted based on karyotype analysis and physical mapping using fluorescence in situ hybridization. As a result of karyotype analysis by feulgen staining, somatic chromosome numbers of A. japonica and A. macrocephala were 2n=24. The length. of the mitotic metaphase chromosomes of A. japonica ranged from $0.70\;to\;1.60{\mu}m$ with a total length. of $12.11{\mu}m$ and the homologous chromosome complement comprised six metacentrics, five submetacentrics and one subtelocentrics. On the other hand, the length of the mitotic metaphase chromosomes of A. macrocephala ranged from $0.90\;to\;2.35{\mu}m$ with a total length of $16.58{\mu}m$ and the homologous chromosome complement comprised seven metacentrics and five submetacentrics. The total length of A. japonica chromosomes was shorter than that of A. macrocephala, but A. japonica had one subtelocentrics (chromosomes 4) different from A. macrocepha1a. chromosomes. The F1SH technique using 17S and 5S rDNA was applied to metaphase chromosomes. The signals for 17S rDNA were detected on the telomeric regions of chromosomes 4 and 5 in both A japonica and A. macrocephala. The 5S rDNA signal was found in the short arm of chromosome 1.

• 한국습지학회지
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• 제11권2호
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• pp.1-7
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• 2009

우리나라 하천변 홍수터의 복원수종을 선발하기 위하여 우리나라 낙엽성 참나무 주요 6종의 유식물을 일반 토양(대조구)과 뿌리가 잠기는 침수된 토양에서 재배하여 그 생육변화의 차이를 분석하였다. 생육분석에 사용한 항목은 잎 수, 잎 길이, 잎 폭, 잎 면적, 지상부 길이, 줄기 길이, 줄기 직경, 뿌리 길이, 식물체 길이(뿌리 길이+줄기 길이), 잎 무게, 줄기 무게, 뿌리 무게, 식물체 무게 등 13가지 형질이다. 졸참나무는 관찰한 13가지 모든 형질에서 침수처리구에서도 잘 자라 대조구와 생육 차이가 없었다. 갈참나무는 식물체 길이 만, 떡갈나무는 잎 길이 등 4개 형질에서, 굴참나무는 잎 수 등 6개 형질에서, 상수리나무는 뿌리 길이 등 7개 형질에서, 신갈나무는 잎 수를 제외한 12개의 형질에서 대조구보다 침수 처리구에서 못 자랐다(p<0.05). 전체적으로 볼 때 낙엽성 참나무류의 침수에 대한 내성의 순서는 졸참나무>갈참나무>떡갈나무>굴참나무>상수리나무>신갈나무 순으로 감소하였다. 따라서 참나무류를 하천변의 홍수터 복원 시에는 졸참나무나 갈참나무를 식재하는 것이 바람직하다.

• Journal of Biosystems Engineering
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• 제29권2호
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• pp.109-120
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• 2004

To obtain basic information for precision agriculture, spatial variability of rice growth condition was evaluated in 100m ${\times}$100m paddy field. The rice growth condition of four hundred locations in the field were investigated to analyze the spatial variability of their properties ; SPAD, plant length and tiller number. Geostatistical analysis was carried out to examine within-field spatial variability using semivariograms and kriged maps as well as descriptive statistics. Descriptive statistics showed that the coefficient of variation for SPAD, plant length, and tiller number exceeded 5.70 %, suggesting a relatively high variability. Geostatistical analysis indicated a high spatial dependence for all the properties except for the second tiller number. The range of spatial dependence was about 20 m for SPAD, plant length, and tiller number. Based on the results of spatial dependence, kriged maps were prepared for the properties to analyse their spatial distribution in the field. The results reflected the history of field management. In conclusion, the need for site-specific field management and possibility of precision agriculture were demonstrated even in an almost flat paddy field.