• 아시안잔디학회지
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• 제11권1호
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• pp.9-22
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• 1997

This study was performed to elucidate the mechanisms involved in efflux process of phosphate from intact and excised roots of Oryza sativa (Tongil). The rapid loss of phosphate during the first 40-minutes of treatment is mainly from the cytoplasmic fraction, and the gradual loss taking place afterwards is possibly reflecting the losses at the tonoplast. During the first 60 minutes, loss of phosphate from the excised roots treated with KCN was more rapid than the control but slower thereafter. The effect of $CaCl_2$ and KCl appeared to decrease the rate of phosphate efflux in excised roots of rice. The mechanism of phosphate efflux by rice roots seems to be passive and oscillatory in the short period. Key words: Oryza sativa(Tongil), Phosphate efflux.

• The Korean Journal of Ecology
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• 제7권2호
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• pp.85-90
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• 1983

There was a decrease in nitrate reductase activity (NRA) measured in vivo in rice roots (Oryza sativa cv. Tongil) grown in anaerobic culture solution. But it was reversed by addition of malonate to the in vivo nitrate reduction assay medium. Malonate increased the in vivo NRA during 2-5 hours incubation and decreased it in longer incubation hours. In vivo NRA was stimulated by addition of NaHCO3 to the assay medium, but not by Na2CO3. The stimulation of NRA by NaHCO3 was not observed in shoot removed rice roots. It is suggested that CO2 from NaHCO3 is carboxylated by phosphoenol pyruvate carboxylase, results in increasing the malate contents in the roots, and stimulates the in vivo NRA. NADH needed in nitrate reduction is supported by malate oxidation. In rice roots, it seems probable that malate oxidation in the mitochondria is more important to nitrate reduction than malae oxidation in cytoplasm.

• 한국작물학회지
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• 제43권3호
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• pp.161-167
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• 1998

Root and shoot development of two rice (Oryza sativa L.) cultivars with different genetic backgrounds was studied with reference to their relative growth. Tongil type (indica-japonica hybrid) cultivar 'Kuemkangbyeo' and japonica cultivar 'Koshihikari' were grown in $5000^{-1}$ a Wagnar pots under flooded condition. Three plants with roots of both cultivars were taken in every phyllochron through the heading stage to record morphological characteristics of shoot and root system. Compared to Koshihikari, Kuemkangbyeo produced more tillers and had greater shoot weight and leaf area per hill. Length and weight of the root system in both cultivars increased exponentially with time. At the same time, root system development was significantly faster in Kuemkangbyeo than in Koshihikari after the panicle initiation stage. As a result, Kuemkangbyeo has a vigorous root system which consists of larger number of nodal roots compared to Koshihikari. Also, the root length and weight per unit leaf area of Kuemkangbyeo were larger than those of Koshihikari in the later half of growing period, which suggests possible higher physiological activity of the root system of Kuemkangbyeo which is known as a high-yielding cultivar. The relationship between root traits (crown root number, total root length, and root dry weight) and shoot traits (leaf area and leaf+culm dry weight) in both cultivars closely showed allometry until the flag leaf stage.

• 한국작물학회지
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• 제27권3호
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• pp.218-222
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• 1982

간탁답과 Leaf-cutting method를 이용하여 수종의 수도품종에 대하여 내염성을 검토한 결과는 다음과 같다. 1. 간탁답에 이항 후 초기 출근량은 밀양 30호와 조생통일이 양호한 편이었다. 2. Leaf-cutting method를 이용한 내염도 측정에서도 조생통일과 밀양 30호가 출근량이 높았다.

• 농업과학연구
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• 제28권1호
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• pp.1-7
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• 2001

RAPDs 분석에 의한 양친의 유전적 유사성 정도가 F1 잡종강세 예측에 효율적으로 이용될 수 있는지 알아보고자 통일형 6 품종(밀양42, IR747, 백운찰벼, 삼강벼, 수원307, 이리356) 간 반이면 교배 F1 15조합을 작성하였다. 양친과 F1을 공시하여 조사한 수량 등 8개의 특성과 RAPDs 분석을 통해 구한 양친의 유전적거리와의 관계를 조사하였다. 120개의 Operon 프라이머를 6개 품종의 DNA 증폭에 이용한 결과 3367개의 밴드가 발생되었으며 이중 168개가 6개 품종 중 1개 이상의 품종에서 변이를 보였다. 6품종간 유전적 거리는 최소 0.157(백운찰벼와 수원 307호 간), 최대 0.383(삼강벼와 이리356호 간)의 분포를 보였다. 잡종강세의 정도는 정조수량(129%), 수당립수(125%), 수장(109%) 등이 높은 잡종강세를 보였고, 유전적거리는 수당립수와 통계적으로 유의한 부의 상관을 보였지만, 정조수량, 천립중 등과는 유의한 상관을 보이지 않았다.

• 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.

• Journal of Plant Biotechnology
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• 제39권3호
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• pp.169-174
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• 2012

Quantitative trait loci (QTLs), which were related to the ability of callus induction and plant regeneration in seed culture of rice, were analyzed using a mapping population from a cross between the rice cultivars 'Samgang' (tongil type) and 'Nagdong' (japonica). A tongil type rice cultivar, 'Samgang' showed lower frequency (20%) of plant regeneration than that (35%) of japonica rice, 'Nagdong'. Transgressive segregations were observed for the ability of callus induction and plant regeneration from the seed-derived calli of 58 doubled haploid (DH) lines. The ability of plant regeneration of 58 doubled haploid lines showed a continuous distribution with comparatively wide range (10.0 to 66.7%) of variation. Composite interval mapping analysis was used to identify the QTLs controlling callus induction and plant regeneration ability. Four significant QTLs, qCWS6, qCWS8, qCWS9 and qCWS11, associated with callus weight per seed were detected on chromosomes 6, 8, 9, and 11 with LOD values of 3.30, 2.60, 2.70 and 2.43, explaining 36% of the total phenotypic variation. Three significant QTLs, qPR1, qPR6, and qPR11, for the ability of plant regeneration were located on chromosome 1, 6, and 11 at LOD score of 2.25, 2.15 and 2.55, accounting for 24 % of the total phenotypic variation. The present study should be useful for improving the efficiency of plant regeneration in tissue culture of indica rice by means of marker-assisted selection.

• 한국작물학회지
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• 제44권1호
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• pp.70-73
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• 1999

This study was conducted to ascertain the chromosomal locations and effect of quantitative trait loci (QTL) associated with the physical traits of rice (Oryza sativa L.) eating quality. One hundred sixty four recombinant inbred lines (MGRILs) of F$_{11}$ were derived from the cross between Milyang 23 (Tongil type) and Gihobyeo (japonica type). They were evaluated for six physical traits of cooked rice. Transgressive segregation was observed for all examined traits. Significant QTL were detected (LOD$\geq$2.0) in three traits, including single QTL for adhesiveness, gumminess, and chewiness of cooked rice, respectively. Phenotypic variation explained by each QTL ranged from 6.3% to 14.6%. However, no significant QTL was detected for hardness, cohesiveness, and elasticity of cooked rice. Pleiotropic effects of single QTL on different traits are observed.d.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1996년도 추계 학술대회지
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• pp.28-29
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• 1996

• 한국작물학회:학술대회논문집
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• 한국작물학회 1996년도 추계 학술대회지
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• pp.30-31
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• 1996