• 대한수학회지
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• 제53권2호
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• pp.433-446
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• 2016

We construct projective embeddings of horospherical varieties of Picard number one by means of Fano varieties of cones over rational homogeneous varieties. Then we use them to give embeddings of smooth horospherical varieties of Picard number one as linear sections of rational homogeneous varieties.

• Journal of Crop Science and Biotechnology
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• 제10권4호
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• pp.265-276
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• 2007

The 13 major blast resistance(R) genes against Magnaporthe grisea were screened in a number of Korean rice varieties using molecular markers. Of the 98 rice varieties tested, 28 were found to contain the Pia gene originating from Japanese japonica rice genotypes. The Pib gene from BL1 and BL7 was incorporated into 39 Korean japonica varieties, whereas this same gene from the IRRI-bred indica varieties was detected in all Tongil-type varieties. We also found that 17 of the japonica varieties contained the Pii gene. The Pii gene in Korean rice varieties originates from the Korean japonica variety Nongbaeg, and Japanese japonica varieties Hitomebore, Inabawase, and Todorokiwase. The Pi5 gene, which clusters with Pii on chromosome 9, was identified only in Taebaeg. Thirty-four varieties were found to contain alleles of the resistance gene Pita or Pita-2. The Pita gene in japonica varieties was found to be inherited from the Japanese japonica genotype Shimokita, and the Pita-2 gene was from Fuji280 and Sadominori. Seventeen japonica and one Tongil-type varieties contained the Piz gene, which in the japonica varieties originates from Fukuhikari and 54BC-68. The Piz-t gene contained in three Tongil-type varieties was derived from IRRI-bred indica rice varieties. The Pi9(t) gene locus that is present in Korean japonica and Tongil-type varieties was not inherited from the original Pi9 gene from wild rice Oryza minuta. The Pik-multiple allele genes Pik, Pik-m, and Pik-p were identified in 24 of the varieties tested. In addition, the Pit gene inherited from the indica rice K59 strain was not found in any of the Korean japonica or Tongil-type varieties tested.

• 한국작물학회지
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• 제50권5호
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• pp.309-318
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• 2005

Higher level of KCl application stimulated both leaf area index and leaf area duration in all cassava varieties, while the leaf and tuber number of the bitter varieties (high cyanide-level varieties) decreased in proportion to the level of KCl application. The root/shoot (R/S) ratio and harvest index (HI) were negatively related with the level of KCl application in all cassava varieties. The bitter varieties obtained the lowest R/S ratio at the level of 100 - 150 kg KCl $ha^{-1}$, while the sweet varieties (low cyanide-level varieties) acquired the highest values at the level of 50 - 150 kg KCl $ha^{-1}$. Also, the sweet varieties showed the lowest HI at the level of 250 kg KCl $ha^{-1}$, but the bitter varieties at the level of 150 kg KCl $ha^{-1}$. At 6 - 8 months after planting, the sweet varieties tended to obtain higher starch content of roots (tubers) at the level of 50 - 150 kg KCl $ha^{-1}$, while the bitter varieties at the level of 150 - 250 kg KCl $ha^{-1}$. Relatively lower level of 50 - 150 kg KCl $ha^{-1}$ was more appropriate for decreasing hydrocyanic acid (HCN) content of roots (tubers) in the sweet varieties at the harvest time, and the level of 250 kg KCl $ha^{-1}$ was adequate to decrease not only HCN content of leaves but also that of roots (tubers) in the bitter varieties during the growing period. To obtain higher yield and starch content of tubers, and lower HCN content of roots (tubers), it was recommended that the sweet varieties are applied with the level of 50 - 100 kg KCl $ha^{-1}$ and the bitter varieties with the level of 150 - 200 kg KCl $ha^{-1}$, respectively, in Latosol soils of Bogor areas, West Java.

• 한국작물학회지
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• 제31권2호
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• pp.162-166
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• 1986

피맥5품종, 과맥5품종 및 맥주맥5품종 등 15품종을 공시하여 대맥절간의 조직형태와 외부형태의 품종간 차리 및 형질들간의 상호관연성을 구명하기 위하여 실시한 시험으로 그 결과를 요약하면 아래와 같다. 1. 상위절간장(상위로부터 1∼3절간)은 맥주맥>피맥>과맥의 순으로 길었으며, 하위절간장 (상위로부터 4∼5절간)은 과맥>피맥>맥주맥의 순으로 길었다. 2. 절간의 굵기는 과맥>피맥>맥주맥의 순으로 굵었고, 올보리, 세도하다가, 무안보리 및 광성이 굵은 경향이었다. 3. 간벽 두께는 상위절간(과맥>피맥>맥주맥), 하위절간(피맥>맥주맥>과맥)의 순으로 두꺼웠다. 4. 상위 제 1절간의 대유관속수는 피맥품종들이 과맥과 맥주맥품종들 보다 많았다. 5. 대유관동 크기는 피맥과 과맥품종들이 맥주맥품종들 보다 큰 경향 이었다. 6. 대유관동 크기와 간벽 두께 및 절간의 굵기와는 유의한 정상관을 나타냈고, 간벽 두께와 절간장 및 간장과는 부의 상관관계를 나타냈으며, 간벽 두께와 절간 굵기와는 유의한 정의 산관을 보였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제12권1호
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• pp.35-39
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• 2006

Fifty-six indigenous and twenty nine exotic mulberry varieties were screened against powdery mildew, Myrothecium leaf spot, Pseudocercospora leaf spot, sooty mold and bacterial leaf spot for a period of three years under field condition. The percent disease index (PDI) was recorded during peak season of the foliar diseases. Out of eighty-five varieties studied, ten varieties were highly resistant and eight were resistant to powdery mildew; six varieties were immune and seventy-eight varieties were highly resistant to Myrothecium leaf spot; sixty varieties were highly resistant and 21 were resistant to Pseudocercospora leaf spot; forty four varieties were highly resistant to sooty mold and two varieties were immune and fifty-eight were highly resistant to bacterial leaf spot. Lowest cumulatative disease index was observed in M. multicaulis (7.28) followed by Thailand lobed (7.85) and Italian mulberry (8.06).

• 한국작물학회지
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• 제48권4호
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• pp.339-344
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• 2003

To identify the new source of breeding materials for rice salt tolerance, the salinity tolerance of thirty-four varieties was evaluated under 0.5% saline condition at seedling stage. The salinity score showed highly significant correlations to dry weight and dead leaf ratio. The tested varieties were classified into three groups by visual score, reduction ratio of dry weight, and dead leaf ratio. Eighteen varieties were classified as the highly tolerant group (salinity scores of 1.3-3.7), seven varieties were fallen into the tolerant group (salinity scores of 4.2-5.8), and others were susceptible (salinity scores of 6.7-9.0). In highly tolerant group, most indica varieties including Getu, Dikwee and Kuatic Putic, didn't exsert a panicle under the Korean climate. But six varieties, Xiangcho V, Annapuruna, HP 3319-2wx-6-3-1, Giza 175, and GZ 2447-S-17, GZ 4255-6-3 were suitable to the Korean climate, and their heading date (6-16, August) and culm length (65-78㎝) were similar to the Korean varieties. Accordingly, these varieties can be utilized as crossing materials for the salt tolerance in japonica rice.

• 한국작물학회지
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• 제5권1호
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• pp.45-49
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• 1969

수도재배시기이동시의 품종의 적응성 또는 외국품종도입시 그 적부판단의 기준이 되는 일장 및 온도효과의 본질과 한국품종들의 감응도를 분석비교하였다. 시험결과 공시품종들은 전부 일장에 대하여 비교적 둔감하고 어느 처리일장하에서나 출수하여 한계일장이 없었으나 만생품종은 조생종에 비하여 감광성이 예민하고 기본영양생장기간이 짧었고 조생품종은 기본영양생장성이 컸으며 최적일장은 전품종 10시간전후였다. 또한 온도도 일장과 같이 생육기간에 대하여 영향이 큰 것 같고 저온은 일장의 장단, 품종의 조만에 관계없이 출수를 지연시키고 고온은 기본영양생장기간을 단축시키고 일장감응기에는 별로 영향이 없었다.

• 한국작물학회지
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• 제68권3호
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• pp.99-105
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• 2023

Starch characteristics and pasting properties of Tongil-type rice varieties with different amylose content were analyzed. Three different Tongil-type rice varieties and one Japonica-type rice variety were examined for their properties. Tongil-type rice varieties have longer panicles and higher rice yield (721-765 kg per 10a) than Boramchan, a Japonica-type high-yield rice variety. The protein content of the Tongil-type rice variety was higher than that of Boramchan. Japonica-type rice varieties had lower amylose content than Japonica-type rice varieties, except for Amimyeon (Milyang355). Amimyeon had higher protein content than the other varieties, and its amylose content was particularly high at 39.2%. The distribution of starch granule sizes of the four varieties was similar, and the particle size corresponding to D50 was approximately 87.8-81.9 ㎛. The pasting properties of rice flour varied among varieties. The Dasanbyeo and Hanarum2 amylogram patterns were similar. These two varieties had a higher peak viscosity (PV) and lower setback (SB) than Boramchan. In the case of Amimyeon, the hot paste viscosity (HPV), cool paste viscosity (CPV), and SB were significantly higher than those of the other Toingil-type varieties, and the breakdown (BD) was very low, showing pasting properties significantly different from that of the other varieties. The onset (T_o), peak (T_p), and conclusion temperature (Tc) of gelatinization of rice flour from Amimyeon were lower than those of the other tested varieties. In addition, the gelatinization temperature, measured using differnetial scanning calorimetry (DSC), and BD, measured using al rapid visco analyzer (RVA) were low in Amimyeon. Amylose content showed a high positive correlation with pasting time (PTi), HPV, and SB and a negative correlation with PV and BD.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.69.2-70
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• 2003

For the selection and breeding of chestnut varieties resistant to the chestnut blight fungus Cryphonectria parasitica, disease resistance and susceptibility of 28 varieties widely planted and growing in Korea were evaluated by artificial inoculation of a pathogenic fungus. For this experiment, a typical virulent strain (KCPC-19) was selected. Artificial inoculation was conducted into all varieties by using two different materials and methods, i.e., bark and wood tissue sections in the laboratory and living trees in the field. In the bark and wood tissue section method, the size of necrotic area and canker development on chestnut varieties were examined and compared 4 days after inoculation. There were wide variations of chestnut varieties in disease resistance and susceptibility against chestnut blight fungus, but 3 varieties, Daebo！, Ishizuchi, and Sandae, were shown to be relatively resistant to the disease with the necrotic area of 0.95-1.03 cm2, while Arima was the most susceptible with the size of 2.0 cm2. In the living tree inoculation examined 5 weeks after inoculation, 3 varieties, Daebo, Ishizuchi, and Riheiguri, showed the higher resistance, but Tono 2 did the highest susceptibility among tested varieties.

• 한국작물학회지
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• 제45권5호
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• pp.277-281
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• 2000

Fifty-four Korean native and 28 foreign varieties harvested in 1998 and 1999 were examined for superoxide dismutase (SOD) and peroxidase (POD) activities. The SOD and POD activities of leaves extracts in Korean native and foreign rice varieties showed variation at the heading stage. The activities of SOD and POD changed with growth stage. In comparison of storage duration, the SOD and POD activities of the extract from three months stored seeds in Korean native (CV=53.3%) and foreign rice (CV=57.9%) varieties were higher than that of stored rices for a year in seed extracts although the activities among varieties did not show significant variation. Also, the averaged activity of foreign rice varieties (SOD=12.9%) was relatively higher than that of korean native rice varieties (SOD=10.7%). The test of activity at the enzymatic level related to antioxidative activity suggests that the rice varieties with higher antioxidative potentials can be developed and also may provide information with rice breeder to breed rice variety with a high antioxidative activity.