• 한국작물학회지
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• 제44권2호
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• pp.143-148
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• 1999

Soil moisture condition is an important limiting factor in growth and yield in rice culture. The purpose of this study was to compare the influence on the growth, yield and Quality of rice subjected to soil moisture stress (SMS) at different growth stages. Ajaponica rice cultivar, Dongjinbyeo, was cultured under flooded conditions in a plastic container filled with silty loam soil. The container was subjected to SMS until the initial wilting point (IWP) coincided with about 10% in soil moisture content and about-200 kPa in soil matric potential, and was then irrigated again, at 6 and 5 of main growth stage in 1996 and 1997, respectively. At maturity, the plant height, tiller number, leaf area and top dry weight were decreased more in SMS treatments at the early stage than the late stage. The averaged yield index of SMS to control in both years was lowest at meiosis (62.5%), which primarily resulted from lower percent ripened grain and 1,000 grain weight, and second＇ reduced the spikelet number per panicle and panicle number per hill, and followed at tillering stage (68.5%) which resulted from the lower production in tiller number and top dry matter during and after SMS treatment. The percent-age of read rice in SMS plants varied with the treatment stage as order of lower at meiosis (44.0%), heading (53.9%), panicle initiation (70.1%), tillering (72.1%), ripening (75.8%) and 5 days after transplanting (DAT) (79.0%). Protein content in brown rice was slightly larger in SMS at late growth stage than the control, while the contents of fat and ash differed very little between SMS and control. Contents of Mg and K and Mg/K in brown rice with SMS were lower at some treatment stages such as at ripening or panicle initiation.

• 한국작물학회지
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• 제52권4호
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• pp.469-473
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• 2007

With the aim to analyze stability performance of six promising barley genotypes, eleven yield related characters were evaluated employing varied irrigation treatments under the tropical climate of Northern part in Bangladesh. Analysis of variance(ANOVA), phenotypic index, regression co-efficient(bi) and deviation from regression($s^2_d$) of the individual genotypes were estimated to evaluate the stable performance of the genotypes. A significant interaction was observed between the genotypes and irrigation period($G{\times}T$). Among all the genotypes, BSH-2 showed stable performance for plant height under different irrigation period, where $P>\bar{X},\;bi{\sim}1\;and\;s^2_d{\sim}0$. High phenotypic index, lower bi value and low deviations from regression were observed in case of spikelet number per spike and grain number per spike for genotype BSH-2 and plant height, spike length and harvest index per plant for BB-2 which suggest that those parameters were not usually affected by irrigation. On the other hand the genotype BSH-2 for tiller number and BB-1 for the fertile tiller number were not suitable for favorable moisture content, where $P<\bar{X},\;bi>1.0\;and\;low\;s^2_d$. Thus we suggest that genotype BSH-2 might have transmit high mean and increased phenotypic stability to the next progenies, which may consider as an ideal genotype for developing improved barely cultivars.

• 한국작물학회지
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• 제34권3호
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• pp.252-260
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• 1989

수도 소포자초기 내냉성의 전력환경에 따른 변동과 기구 및 생육특성을 구명코자 품종 도모유다가를 공시, 질소시용량을 pot 당 0.3g외 3수준과 영화분화기~소포자초기직전의 차광을 75%외 2단계로 한 후 소포자초기에 12$^{\circ}C$ 자연광실에서 3일간 저온처리한 후 내냉성을 검토한 결과를 요약하면 다음과 같다. 1. 소포자분화수는 질소시용량간에 차이가 없었고, 약당충실화분수는 질소시용량이 많을수록, 차광정도가 클수록 적었다. 2. 약장과 주두장은 질소시용량과 차광정도에 따라서 대차 없었다. 3. 주두위에 수분된 화분수는 차광정도가 클수록 적었다. 4. 염실율은 대조구에서는 대차 없었으나 저온처리시 질소시용량과 차광정도가 클수록 낮았다. 5. 엽이간장 신장속도는 질소시용량이 적고, 차광정도가 클수록 떨어졌다. 6. 차광정도가 클수록 상위 1, 2 절간장은 짧아졌으나 4정간장은 길어졌다. 7. 일수영화수는 차광정도가 클수록 직선적으로 감소하였다.

• 한국초지조사료학회지
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• 제43권3호
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• pp.122-128
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• 2023

The present study was conducted to analyze agronomic characteristics of 8 ecotypes of Arundinella hirta (A. hirta) and the correlation among them. Changes in phenotypic characteristics of 8 ecotypes were measured at equal intervals of time from May to September. Among ecotypes, Jangsoo-1 has the highest plant height (172.33 cm), number of leaves (9.00) and leaf length (55 cm) while the ecotype Youngduk has the highest leaf width (1.57 cm), fresh mass (26.63 g), dry mass (7.06 g), number of spikelets per spike (53.33), amount of seeds per spike (0.74 g) and amount of seeds per 10 spikes (7.23 g). The ecotype Jinju-1 has the shortest plant height (119 cm) and leaf number (6.33), while Okgye-2 has shortest leaf length (30.67 cm), leaf width (0.93 cm), fresh mass (12.60 g), dry mass (3.30 g), spike length (30.33 cm), spikelet per spike (39.67), amount of seeds per spike (0.61 g) and amount of seeds per 10 spikes (6.00 g). Correlation coefficients were estimated among the studied agronomic characteristics which showed positive and significant association with each other. In the present study, the agronomic data collected would be useful to understand the potential of A. hirta as a forage resource and helpful in selecting the high-yielding genetic resource for future forage improvement.

• 한국작물학회지
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• 제29권4호
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• pp.366-375
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• 1984

수도의 영화수 및 수량에 미치는 기상소모효과를 확인하고저 분얼기, 생식생장기 및 등숙기에 각각 차광율을 자연광의 0,25, 50%로 하여 작물시험장 포장과 주/야온도 20/1$0^{\circ}C$와 30/2$0^{\circ}C$로 제어된 인공기상실에서 실험을 수행하였던 바 그 결과를 요약하면 다음과 같다. 1. 주/야온도 30/2$0^{\circ}C$와 포장조건하에서의 생식생장기 일사불족은 영화수를 감소시켰는데 그 원인을 주로 이차지경분화수 및 영화분화를 억제시킴과 동시에 이차지경퇴화와 영화퇴화의 증가였다. 2. 생식생장기의 기상소모지수와 단위면적당 수수 그리고 이차지경분화수와는 부의 상관경향이었고, 이차지경퇴화율과는 정의 유의상관이 있었다. 이 기간의 기상소모지수는 영하의 분화수와는 부의 상관이, 그 퇴화율과는 정의 상관이 인정되었다. 3. 생식생장기의 차광이 등숙률이나 현미천립중에는 별로 영향을 미치지 않았으나 등숙기의 차광은 등숙율과 현미천립중을 저하시켰다. 4. 수량에 미치는 차광의 영향은 등숙기 $\geq$ 생식생장기, 분얼기순으로 심했다. 5. 호흡은 비교적 저온하에서는 통일에 비해 진흥에서 많았으나 3$0^{\circ}C$이상의 고온에서는 오히려 통일에서 컸고 호흡계수(Q$_{10}$ )은 통일 2.74, 진흥 1.96이었다. 광합성에 대한 호흡의 비는 저온역에서는 통일에 비해 진흥에서 컸으나 32$^{\circ}C$ 이상의 고온에서는 통일이 큰 경향이었다. 6. 동화산물($^{14}$ C)의 전류는 주/야온도 20/1$0^{\circ}C$에서는 진흥에 비해 통일에서 현저히 억제되었으나 주/야온도 30/2$0^{\circ}C$ 하에서는 품종간 차이가 없었다. 전류에 미치는 차광의 영향은 주/야온도 20/1$0^{\circ}C$ 하에서는 거의 없었으나 30/2$0^{\circ}C$ 하에서는 차광도가 커질수록 심했다.

• 한국작물학회지
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• 제47권6호
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• pp.479-485
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• 2002

일반계인 추청벼, 화성벼와 통일계인 남풍벼를 공시하여 질소시비량(6, 12, 18, 24, 30kg/10a), 분시방법(기비-분얼비-수비; 50-25-25%, 30-30-40%) 및 생식생장기의 차광처리 (유수분화 후 15일, 30일 및 출수전 30일간)가 단위면적당 영화수형성에 미치는 영향을 검토하였으며 결과를 요약하면 다음과 같다. 1. 단위면적당 수수는 질소시비량 24kg/10a까지 시비량의 증가에 따라 직선적으로 증가하였고 분시방법에 따른 차이는 없었다. 생식생장기의 차광처리에 의해 추청벼에서만 수수의 유의한 감소가 나타났는데, 생식생장기 30일간의 차광처리에서 수수의 감소가 가장 크게 나타났다. 2. 수당 1차지경수는 질소시비량 18kg/10a까지 시비량의 증가에 따라 다소 증가하는 경향이었으나 증가폭은 크지 않았으며, 분시방법에 따른 차이는 없었다. 단위면적당 1차지경수는 질소시비량 증가에 따라 증가하였는데 이는 수당 1차지경 증가보다는 단위면적당 수수의 증가가 주원인이었다. 차광에 따라서는 추청벼에서만 단위면적당 1차지경수의 유의한 감소가 있었으며, 이는 수당 1차지경수의 감소에 의한 것이 아니라 단위면적당 수수의 감소에 의한 것이었다. 3. 수당 2차지경 분화수는 질소 12-18kg/10a까지는 시비량의 증가에 따라 다소 증가하는 경향이었으나, 2차지경 퇴화수는 분화수가 많아짐에 따라 증가하여 수당 2차지경수는 질소 시비량에 따른 차이는 작았다 생식생장기의 차광처리에 의해 수당 2차지경분화수에는 차이가 없는 반면, 퇴화 2차지경수에는 큰 차이가 있었다. 단위면적당 2차지경수는 질소시비량이 18kg/10a까지 증가함에 따라 많아졌으나 분시방법에 따른 차이는 없었으며, 차광처리에 따라 유의하게 감소하였다. 4. 단위면적당 영화수는 18-24 kg/10a까지는 질소시비량 증가에 따라 증가하였으나 그 이상에서는 더 이상 증가하지 않았고, 분시방법간에는 차이가 없었다 생식생장기 차광에 의해 단위면적당 영화수가 감소되었는데, 유수분화기후 30일간의 차광처리에서 가장 컸고, 수잉기 15일 차광처리에서 감소정도가 가장 적었다. 5. 단위면적당 영화수의 변이에는 영화수 구성요소중 단위면적당 수수와 2차지경상의 영화수의 변이가 기여하는 정도가 가장 컸으며, 1차지경의 기여도가 가장 적었다.

• 한국작물학회지
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• 제69권1호
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• pp.15-24
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• 2024

Environmental factors play an important role in crop growth and development. In recent years, climate change has become a challenge that limits environmental factors. Light is an important environmental factor for photosynthesis in rice. In addition, temperature is one of the most important factors for rice production; thus, a 1℃ increase in temperature because of climate change can affect rice growth and development. Therefore, we investigated the effect of shading on the growth characteristics of rice under different temperature conditions from the vegetative stage to the flowering stage. Plants were grown at three different temperatures: 26℃/16℃ for 21℃, 29℃/19℃ for 24℃, and 22℃/32℃ for 27℃ in a phytotron. A 55% shade treatment was applied after 10 days of transplanting until the flowering stage. Plant height was not affected by the shading treatment. In the maximum tiller number response to shading, a lower tiller number and growth speed of tiller was found in the 27℃ condition. Among leaf characteristics, shading increased the flag leaf area, length, width, and effective leaf area; however, it decreased the leaf number on the main stem, especially at 27℃. In terms of stem characteristics, shading affected culm wall thickness in both varieties. Finally, regarding the panicle characteristics, lower panicle numbers, spikelet numbers per panicle, primary numbers, and secondary numbers per panicle were found under the shading treatment. Most of the desirable characteristics were affected by the shading treatment at 27℃. Overall, these results indicated that shading had a greater effect on rice plant growth at high temperature.

• 한국유기농업학회지
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• 제7권2호
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• pp.189-195
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• 1999

Under the no-till direct-sown rice-vetch cropping systems, where whole chopped rice straw were returned to the paddy surface at combine harvest and whole-plant of Chinese Milk Vetch(Astragalus sinicus L.) was submerged after direct-sowing, three levels of nitrogen top-dressed(0, 2, 4 kg N/10a) without basal N and two levels of sowing rate were applied into the paddy field in expectation of the enhancement of nitrogen efficiency and protection of agricultural environment in reduced N-fertilizer level. A cultivar, Dongjin, was direct-sown on May 30, 1996. Characteristics of rice growth and physicochemical properties of rice plant were observed. Under the system, reduced total N(4 kg N/10a) resulted in high panicle numbers. N-top dressed toward at later growth stages enhanced the ratio of panicle-producing tillers and at spikelet numbers per panicle. As N-level increases, DM yields of leaf and stem at heading were increased. Maximum grain yield was obtained at 4kg N/10a and major attributed factors to grain yield in this case were the number of grains per unit area and the ratio of ripened grain.

• 한국작물학회지
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• 제58권2호
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• pp.107-112
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• 2013

고온발생시 과연 sink가 적은 것이 등숙에 유리한지를 검토하기 위해, 1. 등숙기간 동안 적온인 $22^{\circ}C$와 고온인 $27^{\circ}C$에 처리한 후 천립중 감소율과 현미완전미감소율 비교하여 국내품종들 중에서 고온등숙에 강한 품종(동안벼)과 약한 품종(일품벼)를 선발하였다. 2. 고온에 대한 두 품종의 차이를 이삭형태 관점에서 비교한 결과 동안벼와 일품벼는 약세영화와 강세영화간의 비율에서는 큰 차이가 없었으나 총영화수에서 일품벼가 더 많았다. 따라서, 많은 영화수를 고온에서의 천립중 감소의 원인으로 가정하여 영화수 조절을 통한 등숙특성 개선을 시도하였다. 3. 이를 위해 약세영화를 제거하여 영화수를 조절한 결과 천립중은 개선이 가능한 것으로 생각되었으나 현미완전미율에서는 효과가 없었다. 4. 따라서, 천립중은 동화산물의 공급균형과 관련된 문제로 추정되는 반면 현미완전미율은 영화 내부의 전분축적과 관련된 대사이상으로 생각되며, 고온 등숙 문제를 해결하기 위해 영화수를 조절하는 것은 한계가 있을 것으로 생각된다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.95-95
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• 2017

Lodging is a serious issue in rice production, because it drastically decreases the biomass production and grain yield. Since the Green Revolution, the lodging resistance has been increased by lowering the moment of above-ground parts due to the short culm by the semi-dwarf gene sd1. However, it has been pointed out that sd1 alone has suppressive effects for biomass production and yield. To increase rice yield, the long-culm and large panicle type varieties with a superior lodging resistance need to be developed. To improve the lodging resistance and yield of these type varieties, it would be effective to identify novel alleles for these traits underlying natural variations in rice and to pyramid these alleles to a single rice variety. In order to perform this strategy, we have developed new rice lines derived from crosses among varieties with superior alleles. At first, TULT-gh-5-5 was selected from a cross between strong culm and high biomass variety Leaf Star and high-yielding variety Takanari, and TUAT-32HB was selected from a cross between high-yielding variety Akenohoshi and Takanari. Then, we developed the super thick-culm and super grain-bearing line, LTAT-29 derived from a cross between TULT-gh-5-5 and TUAT-32HB. In the current study, to identify the QTLs and genes relating to the strong culm and the high yield of LTAT-29, we performed QTL analysis using SNPs markers with $F_2$ population derived from a cross between LTAT-29 and Takanari. LTAT-29 has never lodged throughout the growth period despite it had long culms and heavy panicles. LTAT-29 had a larger outer diameter of the culm and twice the size of the section modulus than Takanari. As a result, the bending moment at breaking of LTAT-29 was significantly larger than that of Takanari. Brown rice yield of LTAT-29 was $9.2t\;ha^{-1}$ about 10% higher than that of Takanari due to the larger number of spikelets per panicle. LTAT-29 had a greater number of secondary branches per panicle. In the $F_2$ population between LTAT-29 and Takanari, we found continuous frequency distributions in the section modulus and the spikelet number per panicle. Two QTLs increased the section modulus by the alleles of LTAT-29 were detected on Chr.1L and Chr.2L. One QTL increased the spikelet number per panicle of Takanari by the allele of LTAT-29 was detected on Chr.1L, and two QTLs increased the number of secondary branches per panicle by the alleles of LTAT-29 were detected on Chr.1L and Chr.4L. It was found that the alleles of these QTLs were the japonica type originated from Leaf Star or Akenohoshi. The novel QTLs for the traits related to super thick-culm and super grain-bearing and their combinations could be utilized for improving the lodging resistance and yield in rice varieties.