• Journal of Plant Biology
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• 제13권1호
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• pp.56-64
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• 1970

The present experiments differning from that conducted by agriculturists with the first consideration of food or seed production were performed in order to investigate the density effect on dry matter production in the artified population of maize. Three experimental plots were established and one seed was sown in the first plot, 2 seeds in the second plot and 3 seeds in the third plot, respectively. The space of each ridge was designed with 30cm in width and 50cm in length. The space of each seed was 4cm and the growth amount by density was measured through three times. The results obtained are as follows: 1) The total growth amount per unit area was in the order of the third, second and first plots until the second sampling. At the third sampling the whole plots showed almost the same growth amount except the first plot which showed a slightly smaller amount. 2) The growth amount per individual plant was in the order of the third, second and first plots until the second sampling, while the first plot showed drastic growth compared with the other two plots at the third sampling. 3) The growth amount by each organ(leaf, stem and root) of the plant body was markedly abundant in the stem of the non-productive part compared with that in the leaf of the productive part. Especially the root was affected remarkably by density and the first plot showed an abundant growth in comparison with the other plots which were too poor to resist the gound surface.

• 현장농수산연구지
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• 제21권2호
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• pp.77-86
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• 2019

To determine none top soil covering in rice seedling nursery method for the sparse machine transplanting, four different sowing methods were tested. Shoot and root length, fresh weight, leaf number and color using leaf color chart(LCC) and SPAD were collected as the data comparison of methods. The seedling height showed the highest growth according to the conventional (230g seed rate of pre-emerged seeds and top-soil covering) > high sowing density 1 (290g seed rate of pre-emerged seeds and top-soil covering) ≥ high sowing density 2(290g seed rate of pre-emerged seeds and none top-soil covering) > high sowing density 3(290g seed rate of iron-coated seeds and none top-soil covering). There was any statistical difference between groups in root length, leaf number, LCC, and SPAD values. Thus, a high sowing density of 290g for rice nursery seedling box was recommended to the sparse machine transplanting in rice cultivation with the none top-soil covering method, enabling convenient handling in transportation and machine transplanting work.

• 한국식물병리학회지
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• 제10권4호
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• pp.319-324
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• 1994

The monoxenic culture of the fungivorous nematode, Aphelenchus avenae, was applied for the control of soil-borne ginseng pathogens such as Fusarium solani and Rhizoctonia solani. Fungivorous nematode populations were measured in a field to examine relationships between the nematode populations and suppression of ginseng root diseases. Inoculation of A. avenae (5000 nematodes per petri-dish) reduced the colonization of the Fusarium mycelium on root discs of ginseng and carrot by 80.0% and 60.5%, respectively. A. avenae also significantly reduced the occurrence of damping-off of ginseng by R. solani pathogenic to ginseng, and no plant damage by the nematode was noted. In a 3-year-old ginseng field infested with Cylindrocarpon destructans, plant missing caused by root rot positively correlated to the density of potato rot nematode, Ditylenchus destructor, but it was reduced with the population of A. avenae, suggesting that A. avenae might inhibit the occurrence of ginseng root rot.

• 한국지반환경공학회 논문집
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• 제17권6호
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• pp.13-21
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• 2016

기존의 토사재해 위험지역 예측은 토질특성과 경사만으로 분석되기 때문에 지역적 특징이 반영되어 있지 않다. 따라서 보다 합리적인 위험지 예측 분석을 위하여 해당지역의 특징을 반영한 토사재해 위험지 예측을 할 필요가 있다. 토사재해 위험지의 특징 중 하나인 수목의 뿌리는 토사 내 점착력을 증가시키는 작용을 하는 것으로 연구되어 왔으며, 수목의 종류에 따라 그 영향이 다른 것으로 알려져 있다. 또한, 지역에 따라 수목의 밀집 정도(수관밀도)가 다양하기 때문에 실제 수목의 분포를 고려하여 토사재해 위험지역 예측을 한다면 보다 합리적인 위험지 예측이 가능할 것이다. 본 연구에서는 세종시 괴화산 일대를 중심으로 수목의 수관밀도를 고려한 뿌리점착력을 사용하여 토사재해 위험지역 예측을 하였으며, 뿌리점착력을 적용하지 않은 토사재해 위험지역 예측 결과와 비교하였다.

• Journal of Ginseng Research
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• 제16권1호
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• pp.31-36
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• 1992

The ultrastructural changes and differentiation mechanism of chromoplasts and leucoplasts from Proplastids in root tip cells of Panax ginseng seedlings were studied with transmission electron microscope. Initial cells have so many proplastids with a few osmiophilic droplets and a lot of mitochon dria at early stage of germination, therefore electron density of cytoplasm is generally higher than that of the other cells just like periblem, plerome and root cap. Proplastids are observed in the initial cells, but only leucoplasts appeared in the central root cap cells. Because root cap cells are derived ultimately from initial cells, the cell organelles in the root cap cells are directly related by those of initial cells. This result postulates that leucoplast is diferentiated from proplastid, and this is the same with other's concepts. On the contrary, the precise observations of chromoplast with crystalline inclusions in the peripheral root cap cells can conclude the direct pathway of chromoplast development from proplastid. Because of the differences of these result from those of other experiments, new scheme of plastid development, direct differentiation of chromoplast from proplastid, can be postulated. And this is the originality of this research on the differentiation of plastids.

• The Plant Pathology Journal
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• 제21권1호
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• pp.73-76
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• 2005

Oriental melon, Cucumis melo L. cv. Geumssaragieuncheon, grafted on Shintozoa (Cucurbit maxima ${\times}$ Cu. moschata) was planted in a greenhouse infested with Meloidogyne arenaria and root galls were examined five months after planting. A gram of root gall was volumed at ca. 10 cm3 and contained in an average of 363 females (170 developing and 193 matured females), 2,120 secondstage juveniles (J2), and 13,074 eggs. In addition, there was 56 J2 per $cm^3$ soil around the infested plant. An oriental melon had an average of 134.6 g of root gall (70% of total root weight) per 0.72 $m^2$ area. In a conservative estimation, an oriental melon plant could accommodate ca. 1.2 ${\times}$ $10^7$ eggs and J2 per 0.72 $m^2$. The eggs contained in root tissues could be an important inoculum source to the next crop and the fate of these eggs are well worth further investigation.

• 한국초지조사료학회지
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• 제17권4호
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• pp.345-350
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• 1997

수정된 Lincoln용액을사용하여 여러가지 목초의 상대생장율, 뿌리/지상부(RlS)비율, 상대적 뿌리 용적 및 표면적 등을 동시에 비교하기 위하여 수경재배법을 개발하였다. 수정된 Lincoln 용액에서 19가지 초종이 모두 잘 자랐으며, 뿌리특성 연구에 긴요하게 이용될 수 있었다. 상대생장율은 조사기간 동안 이상적으로 일정 값을 유지하며 같은 식물체로 성공적으로 측정할 수 있었다. Group 간과 마찬가지로 group 내에서도 초종간 RlS율에 큰 차이가 있었다. 뿌리 조직밀도는 두과목초나 herb보다 화본과에서 낮았다. 뿌리 면적지수는 화본과 목초와 herb가 높았는데 이 면적지수는 각각 다른 초종의 상대척 根界 평가에 유용하게 이용될 수 있을 것으로 사료되었다.

• 한국농공학회논문집
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• 제58권5호
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• pp.71-79
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• 2016

The effects of spot heating for growing the strawberry cultivated in a plastic greenhouse during the winter that were estimated in Nonsan strawberry experiment station located in Chungnam. The temperature of water for heating was controlled by a electric hot water boiler and kept at the range of $22{\sim}24^{\circ}C$. Heating pipes were set up in root zone for root zone heating and very close to crown for crown heating. Spot heating effects were estimated by applying spot heating system in three test factors of heating root zone, crown only and crown plus root zone. The material for crown heating pipe was white low density polyethylene and the nominal diameter of that pipe was 16 mm. The material for root zone heating pipe was flexible stainless steel and the nominal diameter of that pipe was 15A. The flow rate of heating water circulation was 480 L/h and water circulation lasted for all day long. Temperatures, harvest yield by test beds were surveyed from Nov. 10, 2013 to Apr. 29, 2014. The temperature of crown spot for crown heating bed was at the range of $13.0{\sim}17.0^{\circ}C$ during the night and that of crown spot in control bed was at the range of $8.0{\sim}14.0^{\circ}C$. Also, the temperature of root zone for root zone heating bed was at the range of $18{\sim}21.0^{\circ}C$ and that of root zone in control bed was at the range of $13.0{\sim}15.0^{\circ}C$. The cumulative yield growth rate in earlier harvest period (from Dec. 20 to Mar. 15) of crown heating bed was 43% compared with that of control bed and the cumulative yield of crown plus root zone heating bed was 39 % and that of root zone heating bed was 39 %.

• 한국산림과학회지
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• 제99권4호
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• pp.638-644
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• 2010

본 연구는 우리나라의 주요 조림수종인 낙엽송의 용기묘 생산에 필요한 적정 용기개발에 관한 자료를 구축하고자 실시되었다. 1년생 용기묘의 수고 생장은 250 mL 용기에서 19.3 cm로, 2년생은 500 mL 용기에서 56.9 cm로 가장 컸으며, 근원경 생장은 1, 2년생 모두 500 mL 용기에서 가장 큰 것으로 조사되었다. 2년생 용기묘의 건물 생산량은 묘목 전체 및 각 기관별 모두 용기 용적이 클수록, 묘목 밀도는 낮을수록 큰 것으로 조사되었다. WinRhizo 프로그램을 이용한 뿌리형태 특성 분석에서 용적이 큰 용기가 작은 용기보다 전체뿌리길이, 투영단면적, 표면적, 평균뿌리직경, 그리고 뿌리부피가 더 크고 넓은 것으로 분석되었다. 이러한 뿌리형태 특성분석 요소 중 뿌리부피가 용적차이에 따라 가장 큰 영향을 받았는데 500 mL에 비하여 320 mL는 79.5%, 250 mL는 46.8% 수준이었다.

• 한국약용작물학회지
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• 제11권2호
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• pp.109-114
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• 2003

제주도에서 쇠무릎의 뿌리와 포과의 생산을 위한 적정질소시비량을 구명하고자 재식밀도(50, 100주/$m^2$, 1주 2본)와 질소시비량(0, 6, 12, 18, 24, 30 kg/10a)에 따른 생육, 건물수량, 지상부 질소 함량 및 수량 등을 조사하였던 바 그 결과를 요약하면 다음과 같다. 조사한 모든 형질에 대하여 재식밀도와 질소시비량 간에는 상호작용이 없었다. 100주/$m^2$ 재식구에 비하여 50주/$m^2$ 재식구에서 주근장 및 뿌리수는 각각 5%와 52%증가되었고 경엽의 질소함량은 다소 낮았으나 다른 형질에서는 차이가 없었다. 질소시비량은 주경직경, 주당 화서수, 화서당 포과수, 주근장, 주근직경, 포과 질소함량에 영향을 미치지 않았다. 질소시비량이 10a당 0 kg에서 30kg으로 증가함에 따라 SPAD 값은 35.0에서 40.5로, 경엽의 질소함량은 1.09%에서 1.38%로 직선적으로 증가되었다. 질소시비량은 초장, 주당 분지수, 포과 뿌리 건물수량, 주당 근수, 경엽질소수량에 대해서는 2차함수식으로, 주당 화서수에 대해서는 3차함수적인 관계로 분석되었다. 이러한 분석결과 포과 및 뿌리 건물수량이 최대가 되는 질소시비량은 21kg/10a로 추정되었다.