• 한국작물학회지
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• 제46권3호
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• pp.241-247
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• 2001

우리나라 벼 수량의 기상반응을 종합적으로 검토하여 벼 수량예측모델을 구축하고자 1985년부터 1999년까지 15년간 수행한 20개 지역의 벼 지역적응시험 자료를 이용하여 기상에 대한 수량반응의 최대경계선(boundary line)분석을 하였으며, 이에 근거하여 수량예측모형을 설정하였다. 1. 벼의 생육기간을 영양생장기, 생식생장기, 등숙기로 구분하고 각 발육단계를 15-20일 간으로 구분하여 각 시기의 기상요소에 대한 수량반응의 최대경계선은 평균기온( $T_{a}$ )과 일조시수( $S_{h}$)에 대해서는 지수함수 f( $T_{a}$ )=$\beta$$_{0}$(1-exp(-$\beta$$_1$/$\times$ $T_{a}$ ), f( $S_{h}$)=$\beta$$_{0}$(1-exp(-$\beta$$_1$$\times$ $T_{h}$)로 나타났으며 일교차(Tr)는 2차함수 f( $T_{r}$)=$\beta$0(1-( $T_{r}$-$\beta$$_1$)$^2$)로, 이 식에서 상수항 $\beta$$_{0}$를 제거하여 수량에 대한 각 기상요소의 영향도를 0-1로 나타내는 기상지수로 나타내었다. 2. 각 생육시기의 평균기온, 일조시간 및 일교차에 대한 수량반응의 최대경계선이외에 불임에 의한 등숙률 저하와 그에 따른 수량감소를 고려하기 위하여 Uchijima(1976)가 제안한 냉각도일수(cooling degree day)를 출수전 30일간의 생식생장기에 계산하여 이에 대한 수량과 등숙률 반응의 최대경계선을 계산하였는데 냉각도일수가 증가하면 수량이 감소하는 지수함수로 잘 표현되어 기존의 연구들과 같은 결과였다. 3. 기상지수는 벼의 생육기간을 영양생장기, 생식생장기 및 등숙기로 구별하고 각 시기별로 수량 기상지수를 각 기상요소 기상지수를 기하평균하여 산출하였는데 각 시기별 수량기상지수의 수량변이 설명도는 각각 0.383-0.430, 0.460-0.534, 0.4603-0.587로 결정계수는 영양생장기＜생식생장기＜등숙기의 순으로 컸다. 4. 최대경계선 분석방법을 통하여 얻어진 각 생육시기별 수량기상지수를 기하평균하여 구한 종합수량기상지수와 수량과의 직선회귀식을 구하여 수량예측모형(Model I, II, III)을 작성하였다. Model I, II, III)은 각각 결정계수가 0.6512, 0.6703, 0.6129로 모든 생육단계에 걸쳐서 기간을 15-20일 단위로 세분하여 모든 기간의 수량에 대한 기상지수를 고려하여 전 생육기간의 종합수량기상지수를 산출한 Model II가 기상변화에 따른 수량변이의 설명도가 가장 높았다.

• 한국작물학회지
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• 제42권1호
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• pp.89-94
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• 1997

토양수분 부족이 콩의 생육 및 수양에 미치는 영향을 알아보고자 비가림 비닐하우스 안의 베드에서 우리나라 기상여건상 토양수분 부족의 유발가능성이 높은 영양생장기인 신장기에 제 3 복엽기부터 30일간 단수(FNS)와 생육중기인 착협시부터 30일간 단수(BPS), 생육후기 인 입비대시부터 30일간(BSS) 토양수분 부족을 유발시켜 시험을 수행한 결과를 요약하면 다음과 같다. 1. 지상부의 건물중은 FNS 단수처리시 감소율이 가장 컸으며, BPS와 BSS 단수처리시는 대조구와 큰 차이가 없었다. 2. 엽록소 함량은 FNS와 BPS 단수처리시 처리종료 직후에는 현저히 감소되었으나, 수확기에는 회복이 되어 대조구와 유사하였다. 3. 한발처리 종료직후의 토양깊이별 뿌리 분포는 단수처리시 대조구에 비해 지표면 가까이에서 분포되 었으며, 뿌리혹 수와 뿌리혹의 건물중은 BPS 단수처리시 감소가 가장 심하였다. 4. 개체당 협수, 개체당 입중 및 수양은 단수처리시 대조구에 비해 현저하게 감소되었으며, BPS 단수처리시 감소율이 가장 심하였다.

• 한국작물학회지
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• 제46권1호
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• pp.6-11
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• 2001

In this lysimeter experiment, temporal changes of water percolation rate, irrigation requirement and ${No}_3$－-N leaching were investigated under different cultural practices that were no-till direct seeding on flooded paddy (NTDSF), till direct seeding on flooded paddy (TDSF), and transplanting. The highest water percolation rate of 3,001 l/$m^2$ was measured in NTDSF. Others were 2,551 l/$m^2$ and 2,210 l/$m^2$ in TDSF and transplanting. Water percolation rate in NTDSF and TDSF was increased by 36% and 15% compared to transplanting. Water percolation rates in all cultural practices were increased remarkably from the reproductive growth stage and relatively large amount of water loss through percolation was measured even after the reproductive growth stage. A total irrigation requirement was 3,469 l/$m^2$ in NTDSF and 2,898 l/$m^2$ in TDSF. That was equivalent to 45% and 21 % of increase compared to 2,389 l/$m^2$ in transplanting. The largest ${No}_3$－-N leaching through the entire rice growing period was 701 mg/$m^2$ in NTDSF and was followed by 494 mg/$m^2$ in TDSF and 465 mg/$m^2$ in transplanting. The ratios to the total amount of ${No}_3$－-N leaching at the vegetative growth stage, reproductive growth stage and ripening stage were 31 %, 41 % and 28% in NTDSF; 21 %, 48% and 31 % in TDSF; and 18%, 48% and 35 % in transplanting.

• 방사선산업학회지
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• 제6권3호
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• pp.281-287
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• 2012

The model plant, Arabidopsis thaliana is the subject of an international genome research project. Massive doses of ionizing radiation have been shown to induce physiological changes in plants. The wild-type (Ler) Arabidopsis plants were irradiated with 100 Gy and 800 Gy of gamma-ray. Gibberellin (GA) affects developmental processes and responses according to the various environment conditions in diverse plant. The 13 GA isomers were analyzed at vegetative (VE) and reproductive (RE) stages by HPLC. Total GA contents were reduced with the increase in radiation doses at VE and RE stages. Specifically, levels of GA3, GA4, GA12, and GA34 were significantly reduced with the increase of radiation doses. Oligonucleotide microarrays analysis was performed with Arabidopsis plants at different developmental stages and doses of gamma-ray. Through the microarray data, we isolated 41 genes related to GA biosynthesis and signaling transduction. Expression of these genes was also decreased as the reduction of GA contents. Interestingly, in GA signaling related gene expression, gibberellin-responsive protein, putative (At2g18420) was down-regulated at VE and RE stages. Myb21 (At3g27810), Myb24 (At5g40350), and Myb57 (At3g01530) was down-regulated at RE stage. In GA biosynthesis related gene expression, YAP169 (At5g07200) and GA20ox2 (At5g51810) were down-regulated at 100 Gy treatment of VE stage and 800 Gy treatment of RE stage in cytoplasm, respectively. However, exceptively, GA3ox2 (At1g80340) was up-regulated at 100 Gy treatment of RE stage in cytoplasm. In this study, the wild type (Ler) Arabidopsis plants showed differences in response with development stage at the various doses of gamma-rays. GA contents change was reported in gamma irradiated plant.

• 한국초지조사료학회지
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• 제22권1호
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• pp.1-8
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• 2002

Chufa(Cyperus esculentus L.)는 고온성 사초과 식물의 일종으로 여름기간에 잘 자란다. 지상부는 주로 잎으로 구성되어 있으며 지하부는 수염뿌리가 뭉쳐 나있고 끝에 괴경이 달린다. 파종 당년에는 출수가 되지 않고 괴경을 많이 생산한다. 번식은 괴경에서 분얼이 많이 나오는 영양번식을 하며 이 분얼이 다발모양(bunch type)의 포기를 형성한다. 성숙기의 초고는 73~75cm 전후이며 7월 중순에 거의 성장이 완료된다. 포기당 분얼의 수는 7월말까지 급격히 증가하고 8월 이후는 서서히 증가하지만 생장이 빈약하였다. 지상부의 최종 생초수량은 40.3ton/ha, 건물수량은 12.2ton/ha이다. 재생력은 생장초기에는 강하지만 2회 예취후는 재생력이 급격히 떨어진다. 무예취구에서 최종 수확기의 포기당 괴경의 수는 722개, 1$m^2$ 당 생체량은 4.2kg, 건물량은 1.9kg이었다. 예취구의 경우 괴경의 생산량은 예취시기가 늦어질수록 감소하였으나 8월 이후에는 이미 괴경생산이 상당히 진행된 것으로 보였다. chufa의 영양생장기 지상부 사료가치는 우수하였으나 생장이 진행될수록 낮아졌다. 최종 수확한 지상부의 조단백질, NDF, ADF, DMD, TDN 함량은 각각 6.1%, 81.5%, 39.8%, 33.2%39.40%, 괴경의 영양성분은 각각 6.0%, 68.3%, 15.5%, 50%, 51.8%였으며, 특히 지방 함량은 16.2%로 높았다.

• Journal of Microbiology and Biotechnology
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• 제17권10호
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• pp.1645-1654
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• 2007

The total methylotrophic population associated with rice plants from different cultivars was enumerated at three different stages: vegetative, flowering, and harvesting. The bacterial population in the leaf, rhizosphere soil, endophytic in the stem and roots, and epiphytic in the florets and grains were determined from four rice cultivars, Il-mi, Nam-pyeoung, O-dae, and Dong-jin, sampled from three different field sites. The methylotrophic bacteria isolated on AMS media containing 0.5% methanol as the sole carbon source uniformly showed three distinct morphologies, which were recorded as separate groups and their distribution among the various samples was determined using the ecophysiological index. The growth stage at the time of sampling had a more significant effect on the methylotrophic population and their distribution than the field site or cultivar. A similar effect was also observed for the PPFMs, where their population in different plant parts increased from V10 to R4 and then decreased towards stage R9. A canonical discriminant analysis of the PPFM population from different parts of rice showed clear variations among the cultivars, sampled sites, and growth stages, although the variations were more prominent among the growth stages.

• Journal of Applied Biological Chemistry
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• 제48권4호
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• pp.161-166
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• 2005

Among 24 isolates of fluorescent Pseudomonads, 5 isolates named as LPT1, LPT2, LPT3, LPT4 and LPT5 were screened in vitro for their nematicidal activity against cyst forming nematode, Heterodera cajani causing patchiness, poor and stunting growth besides discoloration in Sesamum indicum. Second stage juveniles of H. cajani hatched from egg masses were collected from roots of host plant and subjected to fresh and heat-treated culture filtrate of isolates for 24 h. Mortality of H. cajani was recorded on the basis of parameters used for test organism bioassay. Among these isolates, Pseudomonas aeruginosa LPT5 caused maximum mortality towards second stage juvenile of H. cajani in vitro. Five isolates were used as seed coating for the management of cyst forming nematode H. cajani on sesame in green house condition. The strains LPT5 was better than the other strains in reducing the population of H. cajani both in vitro and in vivo. The reduction in cyst and juveniles population was found to be 49 and 60%, respectively when seeds were coated with strain LPT5. Among other strains, LPT4 was also found to inhibit the cyst and juveniles population 12 and 36% respectively. Increases in early vegetative plant growth parameters recorded in both in vitro and in vivo further revealed the significance of indigenous bacteria in comparison to introduced strain.

• Weed & Turfgrass Science
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• 제3권3호
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• pp.221-224
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• 2014

Genetically modified (GM) crops are not permitted to be cultivated in Korea, but can only be imported as food or feed purposes. The import of GM crops has sharply increased in recent years, thus raising concerns with regard to the unintentional escape of these crops during transport and manufacturing as well as the subsequent contamination of local, non-GM plants. Hence, monitoring of GM crops was studied in or outside of grain receiving ports as well as from feed-processing plants in Korea during July 2008. We observed spilled maize grains and established plants primarily in storage facilities that are exposed around the harbors and near transportation routes of the feed-processing areas. Based on the PCR analyses, a total of 17 GM maize plants and 11 seeds were found among the samples. In most cases, the established maize plants found in this study were at the vegetative stage and thus failed to reach the reproductive stage. This study concludes that, in order to prevent a genetic admixture in the local environment for GM crops or seeds, frequent monitoring work and proper action should be taken.

• 대한원격탐사학회지
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• 제16권2호
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• pp.109-116
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• 2000

This study was carried out to assess the use of RADARSAT data which is C-band with HH polarization for the rice growth monitoring in Korea. Nine time-series data were taken by shallow incidence angle (standard beam mode 5 or 6) during rice growing season. And then, backscattering coefficients ($\sigma$$^{\circ}$) were extracted by calibration process for comparing with rice growth parameters such as plant height, leaf area index(LAI), and fresh and dry biomass. Field experimental data concerned with rice growth were collected 8 times for the ground truth at the study area, Tangjin, Chungnam, Korea. At the beginning of rice growth, backscattering coefficients were ranged from -l6~-l3dB when rice fields were not covered with rice canopy and flooded. At the maximum vegetative stage of rice, backscattering coefficients of the rice field were the highest ranging from -4.4dB~-3.1dB. The temporal variation of backscattering coefficient($\sigma$$^{\circ}$) in rice field was significant in this study. Backscattering coefficient ($\sigma$$^{\circ}$) of rice field was a little bit lower again after heading stage than before. This results show RADARSAT data is promising for rice monitoring.

• 한국환경농학회지
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• 제42권4호
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• pp.311-323
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• 2023

Miscanthus sinensis Andersson (Poaceae) cultivars exhibit excellent visual appeal as ornamental grasses and adapt well to diverse environmental conditions. This study focused on assessing the growth response and landscape durability of seven popular Miscanthus cultivars ('Gold Breeze', 'Strictus', 'Morning Light', 'Variegatus', 'Gracillimus', 'Kleine Fontäne', 'Common') under drought, rainfall and low temperature condition. The test cultivars were transplanted and cultivated on research plots in 2013, with data collected from June 2017 to February 2018. Plant materials were categorized into three types based on the amount of the water lost; group I ('Kleine Fontäne', 'Variegatus', 'Strictus'), experiencing the most significant water loss; group II ('Common', 'Gracillimus'); and group III ('Gold Breeze', 'Morning Light') where the least water loss occurred. The drought resistance index (DRI) remained low as water shortage conditions persisted. The lodged angle underwent more pronounced changes in reproductive growth stage than in vegetative growth stage, notably decreasing after heading. Discoloration patterns were classified into two types: group I ('Common', 'Gold Breeze', 'Kleine Fontäne', 'Strictus') and group II ('Gracillimus', 'Morning Light', 'Variegatus') based on the periods of peak duration.