• 식물분류학회지
• /
• 제43권3호
• /
• pp.208-222
• /
• 2013

한국산 바늘꽃족(Epilobieae Endl.)에 대한 외부형태학적 형질에 근거한 분류학적인 연구를 수행하였다. 그 결과 한국에는 분홍바늘꽃속(Chamerion (Raf.) Raf. ex Holub) 1분류군과 바늘꽃속(Epilobium L.)분류군이 존재하는 것으로 정리되었다. 분홍바늘꽃(C. angustifolium subsp. angustifolium)은 이전까지 바늘꽃속이나 또는 분홍바늘꽃속에 속했으나, 잎이 호생하고, 꽃은 다소 좌우상칭이며 꽃잎의 끝이 갈라지지 않고, 수술 8개의 길이가 거의 비슷한 특징으로 바늘꽃속 식물들과 잘 구분되었다. 가는민바늘꽃(E. platystigmatosum)을 제외한 바늘꽃속 종들의 종자 표면을 전자현미경으로 관찰한 결과 종자 표면은 유두상 돌기(papillose), 그물형 돌기(reticulate), 이랑형 배열의 유두상 돌기(ridged)의 세 가지 형태로 분류되었다. 줄바늘꽃(E. ciliatum subsp. ciliatum)은 속내에서 유일하게 이랑형(ridged) 배열의 유두상 돌기를 지녀 차이가 있었다. 돌바늘꽃(E. amurense subsp. cephalostigma)은 잎의 모양, 털의 형태와 분포, 식물체의 크기와 습성 등에서 호바늘꽃(E. amurense subsp. amurense)과 잘 구별되었다. 회령바늘꽃(E. fastigiatoramosum)과 버들바늘꽃(E. palustre)은 잎이 전연인 점에서 비슷하나, 전자는 잎이 긴 타원형이며 주두가 두상이고 종자의 표면무늬가 유두상인 특징을 보이며, 후자는 잎이 긴 피침형이며 주두가 곤봉형이고 종자의 표면무늬가 그물상인 특징을 가져 잘 구별되었다. 그동안 보고되지 않았던 가는민바늘꽃(E. platystigmatosum)을 새롭게 포함시켰다.

• 한국작물학회지
• /
• 제35권2호
• /
• pp.165-170
• /
• 1990

단간유전자와 GA$_3$ 반응성과의 연관관계를 검토하기 위하여 단간품종들 Fukei 71, 설악벼, Tanginbozu와 이들의 F$_1$ 및 F$_2$에 GA$_3$를 처리하여 절간신장에 미치는 지베렐린의 효과를 검토하였다. 1. 공시한 단간품종들중 설악벼와 Tanginbozu는 GA$_3$에 간장이 크게 신장되었으나 Fukei 71은 GA$_3$에 간장이 신장되지 않았다. 2. 3개 교배조합의 F$_1$은 모두 장간으로 나타나 Fukei 71, 설악벼 및 Tanginbozu는 서로 다른 단간유전자가 간장에 관여하고 있음을 확인하였다. 이들 F$_1$에 GA$_3$를 처리하였을 때 모두 간장이 크게 신장하여서 GA$_3$ 무반응성에 대하여 GA$_3$ 반응성이 우성으로 작용하였다. 3. GA$_3$ 반응성 품종간 조합 설악벼/Tanginbozu의 F$_2$에서는 GA$_3$를 처리한 결과 모든 개체들에서 간장이 신장되어 전체적으로 장간화하였으며 간장은 대체로 9:6:1의 분리경향을 보였다. 4. GA$_3$ 반응성 품종과 무반응성 품종간 조합 즉 설악벼/Fukei 71과 Fukei 71/Tanginbozu의 F$_2$에서는 무처리구에서 대체로 9:7과 9:6:1의 분리경향을 보였으나 처리구에서는 대체로 13:3의 분리경향을 보였다. 5. 설악벼/Fukei 71, Fukei 71/Tanginbozu 조합의 F$_2$에서 GA$_3$ 무반응성 개체만을 골라 Fukei 71로 backcross한 BC$_1$F$_1$ 개체에 GA$_3$를 처리하여 간장과 GA$_3$ 반응성을 조사한 결과, 조합내 개체들간에 간장의 분리를 인정할 수 없었고, GA$_3$ 처리에 무반응성을 보였다. 따라서 Fukei 71의 단간유전자 d50은 GA$_3$ 무반응성과 밀접한 연관이 있는 것으로 생각되었다.

• 한국작물학회지
• /
• 제59권3호
• /
• pp.239-244
• /
• 2014

본 연구는 벼 담수직파재배에서 벼와 피 종의 관수 처리 전 후의 생장 반응과 단백질 발현 양상에 대한 기초자료를 얻고자 수행하였다. 1. 벼와 피종들의 자연 상태에서의 파종후 10일 벼와 피종들의 초장은 10 cm 정도로 차이가 없었으나 파종후 25일부터는 벼에 비하여 피 종들의 초장이 더욱 현저하게 신장하였고, 피 종에서는 식용피의 초장이 현저히 신장되었다. 2. 벼와 피를 생육 초기에 관수하였을 때 벼의 초장은 관수후 3일에서 7일까지도 신장하였으나 피 종들의 초장 신장은 큰 변화가 없었으며, 관수기간 중 벼는 관수후 3일에 1.8배, 관수후 5일에 2.5배, 관수후 7일에 2.7배 정도의 신장률을 보인데 비하여 물피와 돌피는 1.1~1.3배, 식용피는 1.4~1.7배를 나타냄으로서 관수에 대한 저항도는 피에 비하여 벼가 월등히 높은 것으로 나타났다. 3. 관수 종료후 벼와 피의 초장의 생장 속도를 보면 벼는 완만하게 생장하는데 비하여 피종들은 관수 종료후에는 벼보다 급격히 초장이 크게 신장하였고, 피 종에 따라서는 식용피>돌피>물피의 순으로 크게 신장하였다. 4. 관수에 따른 벼와 피의 단백질 spots를 비교한 결과 벼의 잎 단백질 spots은 모두 감소하거나 없어졌지만 피종들의 단백질 spots이 더 선명하게 감소하거나 없어졌다.

• 식물조직배양학회지
• /
• 제26권4호
• /
• pp.251-257
• /
• 1999

본 연구는 낙엽송 (Larix leptolepis)의 종자배로부터 배배양을 통한 식물체 재분화까지의 최적조건을 구명코저 수행되었는데 그 결과는 다음과 같이 요약할 수 있다. 최대 부정아 유도율은 SH배지에 1.0mg/L zeatin을 첨가한 처리구에서 가장 높은 91.7%의 부정아 유도율을 보였으며, cytokinin 혼용처리를 한 부정아 유도는 1.0mg/L zeatin + 1.0mg/L TDZ처리구에서 40.3%로 가장 높은 유도율을 보였다. 그리고 평균 부정아 유도수는 1.0mg/L zeatin+1.0 mg/L 2iP 및 1.0mg/L zeatin+1.0 mg/L kinetin 처리구에서 종자배당 1.9개로 동일한 유도수를 보여 그 효과는 비슷하였다. 부정아의 길이생장은 염류량을 절반으로 줄인 1/2LM배지에서 계대배양하였을 때 가장 높은 27mm의 신초가 생장되어 가장 효과적인 처리구 나타났다. 증식된 신초의 발근율은 5.0 mg/L IBA 및 0.2mg/L NAA 첨가시 23.3%로 가장 높았고 신초에서 유도된 뿌리수는 5.0mg/L IBA처리구에서 신초당 3.5개로 가장 많았다.

• Parasites, Hosts and Diseases
• /
• 제57권6호
• /
• pp.657-664
• /
• 2019

We identified the echinostome metacercariae in Chinese mystery snails, Cipangopaludina chinensis malleata, from Xiengkhuang Province, Lao PDR with morphologies of adult worms recovered. Total 20 snails were examined with artificial digestion method and then the collected metacercariae were orally infected to a mouse and a rat. Adult worms recovered from experimental animals were observed with a light microscope and a SEM. The metacercariae were round, 125×123 ㎛ in average size, with a moderately thick cyst wall, collar spines distributed in the head collar and excretory granules in 2 canals of excretory tube. Adult flukes (3-week-old in a rat) were elongated, ventrally curved and 5.310×1.023 mm in average size. Head collar distinct, bearing 43 collar spines with 5 end group ones on each side. Oral sucker subterminal, prepharynx very short, pharynx well developed, and esophagus relatively short. Cirrus sac well developed, with a saccular seminal vesicle, and ventral sucker very large. Ovary round and on the median line of the body. Testes tandom and elongated. Eggs operculated, elliptical and 90×57 ㎛ in average size. In the SEM observation, the head crown prominent, with 43 collar spines resembled with horns of younger stag. Scale-like tegumental spines were densely distributed on the surface between the head collar and ventral sucker, and their densities were decreased posteriorly. Conclusively, the metacercariae detected in C. chinensis malleata from Lao PDR were identified as those of Echinostoma macrorchis based on the morphological characteristics of adult worms.

• 한국지형학회지
• /
• 제23권1호
• /
• pp.17-33
• /
• 2016

Samples from newly exposed outcrop of sedimentary layers forming Jeongdongjin coastal terrace in Gangreung area are collected and analyzed to find the sedimentary environment. The site are located at the gentle hillslope of the terrace surface area. The height of the outcrop is about 8m and the altitude of it's highest part is 68~73m MSL. The lowest part of this out crop is the partly consolidated sand layer with gravel veneer within it. It is found that this part is not in-situ weathered sand stone through the OSL method. This sand layer is overlain by the gravel layer with sand matrix. The shapes of the gravels from this part are mainly 'platy', 'elongated', and 'bladed' by the index of Sneed and Folk(1958). In addition, mean roundness is not so high. It is sceptical to regard this part as marine sediments which are continuously exposed to erosional processes. The boundary between the lowest sand layer and gravel layer showing the abrupt change in forming material without any mixture or transitional zone, so gravels are seemed to deposited after some degree of consolidation of the lowest sand layer. In addition, the hight of the boundary between layers are changed by the place, so the surface of the partly consolidated sand layer is not flat and has irregularity on topography when it buried by gravels. Main part of this out crop is the poorly sorted coarse gravel(22.4mm) with sand matrix($1.36{\phi}$) layer with at least 2m thick covering the relatively fine gravels discussed above. Over 20% of particles have 'very platy', 'very elongated' and 'very bladed' shape and only less than 5% of particles have 'compact' shape, So this particles are also very hard to be regard as marine gravels which are abraded by marine processes. It can be concluded that this gravel layer formed by fluvial processes rather than coastal processes base on the form of the clast and sedimentary structure. The gravel layer is covered by fine($3{\sim}4{\phi}$) material layers of psudo-gleization which showing inter-bedding of red and white layers. Chemical composition of matrix and other fine materials should be analyzed in further studies. It is attempted to fine the burial ages of the sediment using OSL method, but failed by the saturation. So it can be assumed that these sediments have be buried over 120ka.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2003년도 춘계 학술발표대회
• /
• pp.131-132
• /
• 2003

Leaf discs and apical meristems were cultured in Murashige and Skoog (MS) medium supplemented with cytokinin and auxin at different concentrations. Callus production was observed in all tested media after six days of incubation. Callus produced in the presence of high concentration of NAA (2.0mg/1) was fragile in texture and yellow in colour. Highest callus formation was observed from leaf discs in the medium supplemented with 1.0mg/1 NAA and 0.5 mg/l BAP in dark at $25{\pm}1{\circ}C$. Percentage of callus formation was 95% and mean callus fresh weight was 654.88 43.53 mg. Shoots were induced from the callus after 4 weeks in 1/2MS medium supplemented with BAP and kinetin both at 0.5mg/1. When elongated shoots were separated and transferred into multiplication medium (MS+0.5mg/1 BAP+0.5mg/1 kinetin) multiplication rate was 6.4 after 6 weeks. Higher concentrations of BAP caused callus production at the base. Direct shoot induction was observed from apical meristems in MS medium in the presence of 0.175 mg/1 IAA + 2.25mg/1 BAP and 0.175 mg/1 IAA + 3.0 mg/1 BAP in 16 hour day at $25{\pm}1{\circ}C$. Explants (apical meristems) elongated to form a single shoot forming a callus at the base. Adventitious buds were sprouted out from the base. Percentage explants which producing shoots was 28.57 and 65.5 respectively. Multiple shoot induction was also observed in the same media. Highest multiple shoot production was observed in the presence of 0.175 mg/l IAA and 3.0mg/l BAP, Mean number of shoots per explant was 5.36 and the mean shoot length was $16.66{\pm}4.15$mm. Shoots (20 30m length) were tested for root induction. Excised shoots were transferred into rooting media, which contains different concentrations of NAA and IAA. Best rooting performance was observed in 1/2MS medium supplemented with 0.1mg/1 NAA after 10 days of incubation in 16 hr photoperiod at $25{\pm}1{\circ}C$. Mean number of roots per shoot was 6 and the mean root length was 252mm. Rooted plantlets were transferred into sterile coir dust:sand (1:4) mixture and maintained in a humid chamber for two weeks, They were gradually exposed to the natural environment. After three weeks they were transferred to pots containing coir dust:sand (1:2) mixture for further development where the 90% survival was observed.

• Journal of Plant Biotechnology
• /
• 제2권1호
• /
• pp.35-41
• /
• 2000

Transgenic cabbage (Brassica oleracea ssp. capitata) plants resistant to the commercial herbicide Bast $a^{R}$ were obtained by Agrobacterium tumefaciens - mediated transformation. Hypocotyl segments of in vitro grown plants were infected with Agrobacterium tumefaciens LBA 4404 harboring plasmid pMOG6-Bar which contains hpt and bar genes. Explants were cultured on callus induction medium (MS basal medium + 1 mg/L NAA + 2 mg/L BA + 2 mg/L AgN $O_3$+ 100 mg/L carbenicillin + 250 mg/L cefotaxime) supplemented with 15 mg/L hygromycin. Hygromycin resistant calluses were transferred to shoot regeneration medium (MS basal medium + 0.1 mg/L NAA + 2 mg/L BA + 3% sucrose + 2 mg/L AgN $O_3$+ 15 mg/L hygromycin + 250 mg/L cefotaxime + 100 mg/L carbenicillin). In order to induce roots, elongated shoots were placed on the MS medium without plant growth regulators and hygromycin. Southern blot analysis of several putative transgenic plants indicated that one to five intact copies of Apt and bar genes were incorporated into the genome. Expression of bar gene was confirmed by Northern blot analysis and by herbicide resistant phenotype. Seed progeny from self-pollinated transformants expressed the herbicide resistance and showed Mendelian segregation of the introduced gene.e.

• The Korean Journal of Ceramics
• /
• 제6권2호
• /
• pp.91-95
• /
• 2000

Powder mixtures of $\beta$-SiC-TiC in a weight ratio of 2:1 containing 5-20 wt% additives ($Al_2O_3$-$Y_2O_3$) were liquid-phase sintered at $1830^{\circ}C$ for 1h by hot-pressing and subsequently annealed at $1950^{\circ}C$ for 6h to enhance grain growth. The annealed specimens revealed a microstructure of \"in situ-toughened composite\" as a result of the $\beta$longrightarrow$\alpha$ phase transformation of SiC during annealing. The increase of the content of additives accelerated the growth of elongated $\alpha$-SiC grains with higher aspect ratio and improved fracture toughness. The fracture toughness of SiC-TiC composite containing 20 wt% additive was 6.2 MPa.$m^{1/2}$.2}$.

• Journal of Mechanical Science and Technology
• /
• 제17권3호
• /
• pp.429-439
• /
• 2003

Counter-current two-phase flows of air- water in narrow rectangular channels with offset strip fins have been experimentally investigated in a 760 mm long and 100 mm wide test section with 3.0 and 5.0 mm gap widths. The two-phase flow regime, channel-average void fractions and two-phase pressure gradients were studied. Flow regime transition occurred at lower superficial velocities of air than in the channels without fins. In the bubbly and slug flow regimes, elongated bubbles rose along the subchannel formed by fins without lateral movement. The critical void fraction for the bubbly-to-slug transition was about 0.14 for the 3 mm gap channel and 0.2 for the 5 mm gap channel. respectively. Channel-average void fractions in the channels with fins were almost the same as those in the channels without fins. Void fractions increased as the gap width increased, especially at high superficial velocity of air. The presence of fins enhanced the two-phase distribution parameter significantly in the slug flow, where the effect of gap width was almost negligible. Superficial velocity of air dominated the two-phase pressure gradients. Liquid superficial velocity and channel gap width has only a minor effect on the pressure gradients.