• 한국작물학회지
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• 제47권5호
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• pp.390-394
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• 2002

Spikelet number per unit area(SPN) is a major determinant of rice yield. Nitrogen nutrition status and biomass during reproductive stage determine the SPN. To formulate a model for estimating SPN, the 93 field experiment data collected from widely different regions with different japonica varieties in Korea and Japan were analyzed for the upper boundary lines of SPN responses to nitrogen nutrition index(NNI), shoot dry weight and shoot nitrogen content at panicle initiation and heading stage. The boundary lines of SPN showed asymptotic responses to all the above parameters(X) and were well fitted to the exponential function of $f(X)=alphacdot{1-etacdotexp(gamma;cdot;X)}$. Excluding the constant, from the boundary line equation, the values of the equation range from 0 to 1 and represent the indices of parameters expressing the degree of influence on SPN. In addition to those indices, the index of shoot dry weight increase during reproductive stage was calculated by directly dividing the shoot dry weight increase by the maximum value ($800 extrm{g/m}^{-2}$) of dry weight increase as it showed linear relationship with SPN. Four indices selected by forward stepwise regression at the stay level of 0.05 were those for NNI ($I_{NNI}_P$) at panicle initiation, NNI($I_{NNI}_h$) and shoot dry weight($I_{DW}_h$) at heading stage, and dry weight increase($I_{DW}$) between those two stages. The following model was obtained: SPN=48683ㆍ $I_{DWH}$$^{0.482}$ㆍ $I_{NNIp}$$^{0.387}$ㆍ $I_{NNIH}$$^{0.318}$ㆍ $I_{DW}$ $^{0.35}$). This model accounted for about 89% of the variation of spikelet number. In conclusion this model could be used for estimating the spikelet number of japonica rice with some confidence in widely different regions and thus, integrated into a rice growth model as a component model for spikelet number estimation.n.n.

• 물과 미래
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• 제10권2호
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• pp.81-90
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• 1977

The research is conducted to study the effect of the soil physical properties in the direct sowing culture on the water requirement, growth, and yield of rice with Early-Tongil at the experimental paddy field of the Sangju agri. and seri. junior college in Keyngbuk province from 6th May to 15th September in 1977. The experimental plots are designed with the four plots which are non-irrigated standard (plowing to 15cm), non-irrigated deep lowed (plowing to 25cm), irrigated standard (plowing to 15cm), and irrigated deep plowing plot (plowing to 25cm) and also each plot is repreated four times by the split plot design. The results obtained are summarized as follows: 1) The soil sample was ML to 10cm depth from ground surface and those from 10cm to 20cm depth and from 20cm to 30cm were CL. Each specific gravity was 2. 6, 2. 6 and 2. 7. 2) The weather during culturing period was the sane as the normal year of mean temperature. The precipitation was little and the distribution of it was disordered comparing to normal year but the heavy sunshine gave good effect on ripening. 3) Percolation loss was increased more at the non-irrigated plot than at the irrigated plot, and that of deep-plowed plot was increased more. 4) Grain yield per 10a. of non-irrigated deep plowed plot was 898kg, it was greated than others but there wa no significance. 5) A significant difference in the number of spikelets per panicle was found between nonirrigated plot and irrigated plot, and the number of spiklelets per panicle at the nonirrigated plot was more than that of the irrigated plot. But there was no significance in the other yield components-number of panicle, fertility abd ripening ratio-at the irrigated plot, ut weight of 100 grains was higher at non-irrigated plot. 6) Yield and growth at the deep plowed plot were higher than those of standard plowed plot.

• 한국작물학회지
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• 제38권6호
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• pp.554-559
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• 1993

냉수관개가 벼 생육특성, 수량 및 미질관련 형질에 미치는 영향을 검토하기 위하여 작물시험장 춘천출장소 냉수처리포장에서 실시한 시험 결과를 요약하면 다음과 같다. 1. 냉수구에서는 자연구에 비하여 출수가 10～19일 지연되었고 간장과 수장은 17～31% 단축되었다. 수수는 일정한 경향이 없으며 품종간에 반응이 상리하였다. 2. 냉수구에서 영화수는 이삭당 10～35개가 감소되었고 등숙률이 현저히 떨어졌으며, 정조수량은 오대벼 치악벼등이 높은 수량을 나타낸 반면에 백암벼 소백벼 진미벼등은 낮은 수량을 보였다. 고중은 공시품종 모두 냉수구에서 높았다. 3. 현미 완전미율은 냉수구와 자연구간에 일정한 차이가 없었고 오히려 품종간의 변이가 크게 나타났고, 청미율은 자연구에서 많은 경향이며 연색미는 냉수구에서 월등히 높았다. 4. 백미 투명도및 알칼리 붕괴도는 수구쪽에서 높은 경향이며, 아밀로스 함량은 자연구에서 높았다.

• 농약과학회지
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• 제19권4호
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• pp.394-398
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• 2015

본 연구는 잎집무늬마름병에 대한 약제방제수준을 설정하기 위하여 오대벼를 공시하여 시험을 수행하였다. 잎집무늬마름병 발병정도에 따라 수량에 미치는 관계를 분석하였으며, 수량 구성 요소인 주당 이삭수, 이삭당 립수, 등숙률, 천립중과의 관계를 분석하였다. 그 결과 발병주율에 대한 수량과의 관계는 r = -0.93, 이삭당 립수 r = -0.66, 등숙율은 r = -0.77로 고도의 유의성 있는 부의 상관이 있었으나, 주당 이삭수와 천립중은 유의한 상관이 인정되지 않았다. 따라서 본시험에서는 발병과 상관이 높은 수량에 대하여 경제적 방제수준은 발병주율 7.8%로 설정할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제28권9호
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• pp.1527-1535
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• 2018

Bacterial strain BAS23 was isolated from rice field soil and identified as Bacillus amyloliquefaciens. Based on dual culture method results, the bacterium BAS23 exhibited potent in vitro inhibitory activity on mycelial growth against a broad range of dirty panicle fungal pathogens of rice (Curvularia lunata, Fusarium semitectum and Helminthosporium oryzae). Cell-free culture of BAS23 displayed a significant effect on germ tube elongation and mycelial growth. The highest dry weight reduction (%) values of C. lunata, H. oryzae and F. semitectum were 92.7%, 75.7%, and 68.9%, respectively. Analysis of electrospray ionization-mass spectrometry (ESI-MS) and $^1H$ nuclear magnetic resonance (NMR) spectroscopy revealed that the lipopeptides were iturin A with a C14 side chain (C14 iturinic acid), and a C15 side chain (C15 iturinic acid), which were produced by BAS23 when it was cultured in nutrient broth (NB) for 72 h at $30^{\circ}C$. BAS23, the efficient antagonistic bacterium, also possessed in vitro multiple traits for plant growth promotion and improved rice seedling growth. The results indicated that BAS23 represents a useful option either for biocontrol or as a plant growth-promoting agent.

• Journal of Plant Biology
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• 제12권2호
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• pp.28-42
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• 1969

Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

• 한국작물학회지
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• 제40권4호
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• pp.473-480
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• 1995

냉수처리답에서 적고현상, 간장, 수장 그리고 수수 등 각 형질에 대하여 내냉성이 강한 품종과 약한 품종을 교배하고, 그 후대에 대하여 각 형질의 유전분석을 실시하였던 바, 그 결과를 요약하면 다음과 같다. 1. 적고현상에 대하여 강한 품종과 약한 품종의 교배조합에서 강한 개체와 약한 개체의 F$_2$의 분리비가 7개 조합 중 4개 조합에서 저항성 쪽이 우성으로 3 : 1의 단성잡종분리비를 나타냈다. 2. F$_1$세대와 F$_2$집단에서 간장과 수장은 긴 쪽이 우성이고, 단축이 적게 되는 쪽으로 초우성 또는 불완전우성을 나타냈고, 수수는 많은 쪽이 우성이고, 냉수처리하에서 수수가 오히려 많아지는 쪽으로 초우성을 나타냈다. 3. 냉수답에서 간장, 수장 및 수수의 유전력은 형질 및 교배조합에 따라 다소 차이는 있으나 대체로 높았으며, 자연답보다는 냉수처리답에서 유전력이 높게 나타났다. 4. 각 형질의 잡종강세정도는 간장에서 매우 높았으며, 수장과 수수에서는 대체로 낮게 나타났다. 특히 인디카 /통일형품종의 교배조합에서, 자연답보다는 냉수처리답에서 잡종강세가 높게 나타났다.

• 한국작물학회지
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• 제47권3호
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• pp.221-225
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• 2002

본 연구는 벼 휴립건답직파 절수재매시 완효성비료의 효과를 알아보기 위하여 질소비료를 표준시비(N-160kg/ha) 대비 완효성비료(LCU: 18-12-13%)를 기비로 100%와 80% 시용구 및 기비로 60% 시용하고 속효성비료인 요소로 분얼비 또는 수비로 20%씩 각각 시용하여 시험한 결과를 요약하면 다음과 같다. 1. 생육기간중 지상부 생육은 LCU 100%에서 가장 컸고, LCU 시비량간에는 시비량이 많을수록 컸다. 2. 시비질소의 흡수량은 LCU 100%에서 가장 높았고 질소 시비효율은 LCU 60% + 수비(요소) 20% 시용구에서 가장 높았다. 3. 처리간 수량구성요소를 보면 $m^2$당 수수와 $m^2$당 립수는 LCU 100%에서 가장 많았고, 등숙비율과 현미 천립중은 비슷하였는데, 쌀 수량은 관행인 속효성 시비구 대비 LCU 100%에서 7% 증수되었다. 따라서 벼 휴립건담직파재배에서 관개수 부족시 절수재배가 필요하여 이때에 완효성비료로 시비할 경우 표준시비량(N-160kg/ha) 수준으로 시비해야 할 것으로 생각된다.

• 한국작물학회지
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• 제44권2호
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• pp.149-153
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• 1999

Prediction of rice developmental stage is necessary for proper crop management and a prerequisite for growth simulation as well. The objectives of the present study were to find out the relationship between the plastochrone index(PI) and the developmental index(DVI) estimated by non-parametric phenology model which simulates the duration from seedling emergence(DVI=0) to heading(DVI=l) by employing daily mean air temperature and daylength as predictor variables, and to confirm the correspondency of developmental indice to panicle developmental stages based on this relationship. Four japonica rice cultivars, Kwanakbyeo, Sangpungbyeo, Dongjinbyeo, and Palgumbyeo which range from very early to very late in maturity, were grown by sowing directly in dry paddy field five times at an interval of two weeks. Data for seedling emergence, leaf appearance, differentiation stage of primary rachis branch and heading were collected. The non-parametric phenology model predicted well the duration from seedling emergence to heading with errors of less than three days in all sowings and cultivars. PI was calculated for every leaf appearance and related to the developmental index estimated for corresponding PI. The stepwise polynomial analysis produced highly significant square-rooted cubic or biquadratic equations depending on cultivars, and highly significant square-rooted biquadratic equation for pooled data across cultivars without any considerable reduction in accuracy compared to that for each cultivar. To confirm the applicability of this equation in predicting the panicle developmental stage, DVI at differentiation stage of primary rachis branch primordium was calculated by substituting PI with 82 corresponding to this stage, and the duration reaching this DVI from seedling emergence was estimated. The estimated duration revealed a good agreement with that observed in all sowings and cultivars. The deviations between the estimated and the observed were not greater than three days, and significant difference in accuracy was not found for predicting this developmental stage between those equations derived for each cultivar and for pooled data across all cultivars tested.

• 한국작물학회지
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• 제29권2호
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• pp.128-135
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• 1984

Nepal에서 도입된 수도 'Gamadi' 품종은 Gamadiness 특성(구내성숙성)의 유전분석을 시도하였다. 그 결과를 요약하면 다음과 같다. 1. 본연구에 공시된 표식인자들 즉 제 I 연관군의Cl, nx, Pla, 제III연관군의 Pn, Rd, Pub, 제II, IV, V, VI, VII, VIII, IX, X, XI, XII 연관군의 각각 lg, g, Ps, gh, Hla, la, nl, bl, bc, 및 gl은 과거의 보고와 일치되는 분리비를 나타내어 이 실험에서의 유전분리가 정상적인 것이었음을 입증한다. 2. 'Gamadiness'는 2개의 우성유전자에 의하여 보족적인 작용으로 표현되어 Gamadi 9: 정상7의 분리비를 보였다. 이 2개유전자를 G-a와 G-b로 명명하였다. 3. G-a 유전자는 제Ⅸ연관군의 nl 유전자와 0.37$\pm$0.027의 조환가로 연관되어 있음을 확인하였다. 4. G-b 유전자는 제XI연관군의 bc 유전자와 0.27$\pm$0.061의 절환가로 연관되어 있음을 확인하였다.절환가로 연관되어 있음을 확인하였다.