• The Plant Pathology Journal
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• 제16권3호
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• pp.151-155
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• 2000

A cDNA (Oslls1) encoding Lls1-homologue of maize was isolated from cDNA library of rice (Oryza sativa cv. Ilpum). The 2,138 bp of full length Oslls1 clone contains an open reading frame of 1,623 nucleotides encoding 575 amino acid residues. The deduced amino acid sequence of Oslls1 has a high level of homology with chlorophyll a oxygenases of Arabidopsis thaliana (67%) and Marchantia polymorpha (65%). Southern blot analysis of genomic DNA indicates the existence of a small gene family for Oslls1 in the rice genome. The expression of Oslls1 mRNA was induced in leaves and germinating seeds. Treatment of $H_2O$$_2$significantly down-regulated Oslls1 expression. The expression of Oslls1 mRNA was consititutively down-regulated in the blm, a rice mutant exhibiting spontaneous necrotic lesions. These results suggest that this Oslls1 gene may be involved incell death mechanisms in the blm mutant of rice.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.25-25
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• 2014

Three species of Fusarium, F. fujikuroi, F. verticillioides and F. proliferatum, are known to be associated with bakanae disease of rice [1, 2]. F. fujikuroi infects rice flowers and survive in endosperm and embryo of the seeds. Infected seed is an important source of primary inoculum of pathogens [3]. Seeds of rice (Oryza sativa cv. Boramchan) collected from bakanae-infected field were found to be 96% infected with Fusarium sp., 52% with F. fujikuroi, 42% with F. verticillioides, and 12% with F. proliferatum as determined by incubation method and species-specific PCR assays. F. fujikuroi was detected at lemma/palea, endosperm and embryo whereas F. verticillioides and F. proliferatum were recovered only from lemma/palea by means of component plating test. Seed disinfection methods have been developed to control bakanae disease and prochloraz has been most widely used for rice seeds. Two chemicals formulated with prochloraz (PC 1) and prochloraz + hexaconazole (PC 2) that inhibit biosynthesis of ergosterol strongly reduced the incidence of Fusarium spp. on selective media to 4.7% and 2.0%, respectively. Disease symptoms of rice seedlings in nursery soil were alleviated by chemical treatment; seedlings with elongated leaves or wide angle between leaf and stem were strikingly reduced from 15.6 to 3.2% (PC 1) and 0 (PC 2), stem rots were reduced from 56.9 to 26.2% (PC 1) and 32.1% (PC 2), and normal seedling increased from 0.4 to 13.3% (PC 2). Prochloraz has some disadvantages and risks such as the occurrence of tolerant pathogens [4] and effects on the sterol synthesis in animals and humans [5]. For these reasons, it is necessary to develop new disinfection method that do not induce fungal tolerance and are safe to humans and animals. Chlorine dioxide ($ClO_2$), that is less toxic, produces no harmful byproducts, and has high oxidizing power, has been reported to be effective at disinfection of several phytopathogenic fungi including Colletotrichum spp. and Alternaria spp. [6]. Gaseous $ClO_2$ applied to rice seeds at a concentration of 20 ppm strongly suppressed mycelial growth of Fusarium fujikuroi, F. verticillioides and F. proliferatum. The incidence of Fusarium spp. in dry seed with 8.7% seed moisture content (SMC) tended to decrease as the concentration of $ClO_2$ increased from 20 to 40 ppm. Applying 40 ppm $ClO_2$ at 90% relative humidity, incidence was reduced to 5.3% and resulted in significant reduction of disease symptoms on MS media. In nursery soil, stem rot was reduced from 56.9 to 15.4% and the number of normal seedlings increased from 0.4 to 25.5%. With water-soaked seeds (33.1% SMC) holding moisture in the endosperm and embryo, the effectiveness of disinfection using $ClO_2$ increased, even when treated with only 20 ppm for four hours. This suggests that moisture was a key element for action of $ClO_2$. Removal of the palea and lemma from seeds significantly decreased the incidence of Fusarium spp. to 3.0%. Seed germination appeared to decrease slightly by water-soaking at $30^{\circ}C$ because of increased SMC and by physical damage of embryos from hulling. These results indicate that the use of gaseous $ClO_2$ was effective as a means to disinfect rice seeds infected with Fusarium spp. and that moisture around the pathogens in the seed was an important factor for the action of $ClO_2$. Further investigations should be conducted to ascertain the best conditions for complete disinfection of Fusarium spp. that infect deep site of rice seeds.

• Journal of Photoscience
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• 제9권3호
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• pp.65-70
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• 2002

In the rice leaves treated with methyl viologen (MV), the photochemical efficiency of PSII (or $F_{v/}$F $m_{m}$) was significantly decreased, and significant portion of the photoinactivation process was reversible during the dark-recovery. The dark-reactivation process was relatively slow, reaching its plateau after 2-2.5 h of dark incubation. The damaged portion of functional PSII was 13％, based on the value of I/ $F_{o}$- I/ $F_{m}$ after this dark-recovery period. The reversible photoinactivation process of PSII function in the MV-treated leaves consisted of a xanthophyll cycle-dependent development of NPQ and a xanthophyll cycle-independent process. The latter process was reversible in the presence of nigericin. As well as the increase in the values of Chl fluorescence parameters, the epoxidation process during the dark-recovery after the MV-induced photooxidation was very slow. These results suggest that the photooxidative effect of MV is partly protected by the down-regulation of PSII before inducing physical damages in core proteins of PSII.I.I.I.I.

• 한국토양비료학회지
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• 제32권3호
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• pp.295-303
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• 1999

제강슬래그의 작물재배시 산성토양개량제로서의 이용 가능성을 밝히기 위해 1997년에 공시품종을 동진벼로 하여 순천시 인안동의 간척논, 보성군 유정기 깨시무늬병 대량 발생논 그리고 나주시 남평의 실험논에 무처리, 제강슬래그 4, 8, $12Mg\;ha^{-1}$ 그리고 석회 $2Mg\;ha^{-1}$를 처리하여 벼를 재배하였다. 토양 pH, Ca, Mg, Fe 그리고 규산함량은 제강슬래그 시용량이 증가할수록 높아지는 경향이었다. 토양 pH의 증가는 주로 Ca함량의 증가에서 기인한 것으로 나타났으며 Fe함량은 처리 후 시간이 경과함에 따라 급격히 감소하다가 점차 안정된 값을 보였다. 토양 규산함량도 제강슬래그 시용량이 증가할수록 점차로 높아지는 경향이었고 무처리구나 석회 $2Mg\;ha^{-1}$ 처리구에 비해 유의하게 높아 제강슬래그가 산성토양 개량제, Fe 또는 Si의 공급원으로 이용가능성이 있음을 알 수 있었다. 석회 $2Mg\;ha^{-1}$수준의 토양 Ca함량은 제강슬래그 4 또는 $8Mg\;ha^{-1}$ 처리의 그것과 비슷하여 석회 시용에 의한 토양개량 효과를 얻기 위해서는 석회 시용량의 2~4 배의 제강슬래그를 시용해야 함을 알 수 있었나. 식물체내 무기화학성분 중 식물체내 무기화학성분 중 식물체내 Ca, $SiO_2$ 그리고 Fe함량은 제강슬래그 시용량이 증가할수록 높아지는 경향이었다. 제강슬래그 시용구에서는 생육후기로 갈수록 제강슬래그 4와 $8Mg\;ha^{-1}$ 처리구에서 생육이 양호하였으며 생육후기까지 지속적인 생장이 이루어져 생육후기에는 석회 처리구나 무처리구의 생육량을 능가하였다. 정조수량 및 수량관련 형질은 제강슬래그 4나 $8Mg\;ha^{-1}$ 처리에서 가장 높아 최고 수량을 얻기 위한 제강슬래그 처리수준은 $4{\sim}8Mg\;ha^{-1}$정도로 판단된다.

• 한국유기농업학회지
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• 제27권2호
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• pp.173-191
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• 2019

광역친환경 농업단지에서 전라남도 장흥과 순천 그리고 충청북도 옥천의 벼(Oryza sativa L.) 선도 농가를 선정하여 관행구와 추천구를 각각 지정하여 토양과 벼의 시기별 무기성분을 2017년에 비교하였다. 순천농가는 전년도에 헤어리베치를 파종하였던 추천구를 두었고, 옥천은 관행구에 투입된 비료량의 절반을 시용한 추천구를 포함하였다. 전남 장흥농가에서만 축산농가에서 발생한 우분을 비료로 투입하는 경축순환농업을 수행하였다. 모든 시험구의 토양 pH와 EC는 벼 생육에 적합한 수준으로 관찰되었다. 시기별 토양 pH는 순천농가에서 가장 높았으며 토양 EC는 장흥 관행구에서 가장 높았다. 시기별 토양 T-N 함량은 순천 농가에서 3월부터 6월까지 증가하였고. 시기별 토양 유효 P₂O₅는 장흥농가에서 가장 낮았다. 시기별 토양 치환성 K 함량은 모든 시험구에서 감소하였고 옥천농가에서 가장 낮았다. 시기별 토양 NH₄⁺ 함량은 장흥 관행구에서 6월에 타 시험구보다 90 mg/kg 이상 증가하였다. 시기별 벼의 T-N, P와 치환성 K 함량은 장흥 관행구에서 가장 높았다. 벼의 T-N과 P 함량은 6월부터 9월까지 감소하였고 치환성 K 함량은 2.0~2.5% 수준에서 변동되었다. 시기별 엽록소 함량 지수는 순천 관행구에서 가장 낮았다. 장흥농가의 벼 생산량은 6,303 kg/ha로 옥천 추천구보다 약 두 배 높게 나타났다. 시기별 T-N, P와 K 수지는 옥천 관행구에서 가장 높았고 순천 관행구에서 가장 낮았다. 결과적으로 순천 추천구의 양분수지가 비교적 낮았고 수량이 비교적 높아서 가장 친환경적인 지속가능한 농업을 실천한 농가로 평가되었다.

• 한국환경과학회지
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• 제31권5호
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• pp.413-422
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• 2022

To identify rice (Oryza sativa L.) cultivars suitable for Italian ryegrass (Lolium multiflorum Lam.)-rice double cropping systems, we investigated the yield and grain quality of four different midseason maturing rice cultivars ('Daebo', 'Haepum', 'Haiami', and 'Samdeog') and four midseason-to-late maturing rice cultivars ('Hyunpoom', 'Saeilmi', 'Saenuri', and 'Samkwang') in single rice cropping and Italian ryegrass-rice double cropping systems in paddy fields of Miryang, South Korea. We found that organic matter and available P₂O₅ content slightly decreased, whereas Na content increased, in the soil where Italian ryegrass was cultivated during winter compared to that in the soil that remained fallow during winter. The pH, electrical conductivity, organic matter, and contents of K⁺, Ca²⁺, Mg²⁺, and Na⁺ decreased, whereas the available P₂O₅ content slightly increased, in the soil where rice was harvested in both single and double cropping systems. However, compared to the optimum soil conditions for rice cultivation, available P₂O₅ and K⁺ content were high and Mg²⁺ content was low in both single and double cropping systems. At the heading stage, the culm length and leaf color slightly increased in most of the rice cultivars, whereas the panicle length and number slightly decreased, in the double cropped system. After harvesting, spikelet number and milled rice yield did not show a significant difference between single and double cropping systems. However, the ripened grain rate and weight per thousand grains increased slightly in the 'Saeilmi' and 'Samkwang' cultivars but remained either stable or slightly low in other cultivars in the double cropping system. The milled rice yield was high (> 500 kg/10a) in 'Daebo' and 'Haepum' among midseason maturing rice cultivars, and in 'Saeilmi' and 'Saenuri' among midseason-to-late maturing rice cultivars, in both single and double cropping systems. The head rice rate was high in midseason maturing rice cultivars in the double cropping systems, reaching > 70% in 'Haepum' and 'Haiami' cultivars, whereas it decreased in most midseason-to-late maturing rice cultivars (excluding 'Samkwang' cultivar), in double cropping systems. Particularly, it exceeded > 70% in the 'Saenuri' cultivar in both single and double cropping systems. The protein content in milled rice increased, whereas the amylose content either remained stable or slightly increased, in double cropping systems. The Toyo taste value decreased in all midseason-to-late maturing rice cultivars and slightly increased in the 'Daebo' and 'Haiami' cultivars among midseason maturing rice cultivars in double cropping systems. However, Toyo taste values in the 'Haepum', 'Haiami', and 'Saenuri' cultivars exceeding > 80% in both single and double cropping systems. Therefore, we recommend 'Haepum', 'Haiami', and 'Saenuri' cultivars as candidates for Italian ryegrass-rice double cropping systems due to high yield, head rice rate, and Toyo taste value.

• 농약과학회지
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• 제9권2호
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• pp.153-158
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• 2005

광학활성 1-${\alpha}$-methylbenzylphenylurea 유도체의 bensulfuron-methyl, pyribenzoxim에 대한 약해경감효과를 조사하였다. 대부분의 유도체가 담수토양처리시험에서도 제초제 bensulfuron-methyl에 의한 벼의 근부신장 저해에 대하여 높은 약해경감효과를 나타내었다. 특히, S-이성체의 2,3-diCl 치환체와 2-F-4-Me 치환체는 dymuron 보다 4배 높은 약해경감효과를 나타내었으며 두 치환체들은 동시 혼합처리뿐만 아니라 4일 후의 지연처리에서도 bensulfuron-methyl의 약해를 효과적으로 경감하였다. S-이성체의 2-F-4-Me치환체는 벤조산계 제초제 pyribenzoxim에 대해서도 지상부, 근부 모두 95%의 높은 약해경감효과를 나타내었다.

• Plant Biotechnology Reports
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• 제4권4호
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• pp.281-291
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• 2010

The rice CHLH gene encodes the $Mg^{2+}$-chelatase H subunit, which is involved in chlorophyll biosynthesis. Growth of the chlorophyll-deficient oschlh mutant is supported by mitochondrial activity. In this study, we investigated the activity of mitochondrial respiration in the illuminated leaves during oschlh seedling development. Growth of mutant plants was enhanced in the presence of 3% sucrose, which may be used by mitochondria to meet cellular energy requirements. ATP content in these mutants was, however, significantly lowered in light conditions. Low cytosolic levels of NADH in illuminated oschlh mutant leaves further indicated the inhibition of mitochondrial metabolism. This down-regulation was particularly evident for oxidative stressresponsive genes in the mutant under light conditions. Hydrogen peroxide levels were higher in oschlh mutant leaves than in wild-type leaves; this increase was largely caused by the impairment of the expression of the antioxidant genes, such as OsAPXl, OsRACl, and OsAOXc in knockout plants. Moreover, treatment of mesophyll protoplasts with ascorbic acid or catalase recovered ATP content in the mutants. Taken together, these results suggest that the light-mediated inhibition of mitochondrial activity leads to stunted growth of CHLH rice seedlings.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.290-290
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• 2017

Rice (Oryza sativa L.) is one of the most consumed staple food crop which is energy source as carbohydrate and also is considered as the important antioxidant sources including various phenolic compounds. According to the increasing demand of healthy life, the concern to antioxidant also is increasing because of its health-promoting effect. Phenolic compounds are one of the plant secondary metabolites class, which shows various benefits to preventing or treating chronic diseases. In this study, we have measured the total phenol content from total 647 rice samples using the Floin-Ciocalteau method, and then were selected 30 rice genetic resources classified with high, middle, and low group on the basis of total phenol content. The average of the total phenol content of each group was high-group ($6892.9{\pm}488.5{\mu}g\;GAE/g$) > middle-group ($1428.1{\pm}76.0{\mu}g\;GAE/g$) > low-group ($97.6{\pm}11.4{\mu}g\;GAE/g$). The selected rice samples were analyzed with LC-MS/MS to find the composition and concentration of individual phenolic in rice grain. High-group and middle-group contained large amounts of protocatechuic acid and (+)-catechin whereas low-group showed limited amount. Among high-group samples, rice samples with black pericarp color (IT 174089, IT 220079, and IT 259958) had high content of peonidin-3-O-glucoside. Further, these black rice samples were special since polydatin, rarely found stilbenoid in rice grain, was detected. Overall, both the sum of phenolic acid and the sum of flavonoid were high-group > middle-group > low-group. Also, each group exhibited different phenolic compositions; high-group consisted of flavonoid more than phenolic acid, middle-group and low-group was comprised of phenolic acid rather than flavonoid, and non-pigmented rice was composed by fully phenolic acid. The total phenol content had positive relationships with the sum of phenolic compound (r = 0.64), the sum of flavonoid (r = 0.74) at the significance level of p < 0.0001. In addition, protocatechuic acid and quercetin showed positive correlation with above phenolic composition parameters; in order, r = 0.98, 0.65 for protocatechuic acid and r = 0.73, 0.78 for quercetin (p < 0.0001). In conclusion, the total phenol content assay showed the possibility of utilization as a phenolic composition indicator in rice grain. Also, this result was suggested study pigment on other material.

• 한국잡초학회지
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• 제13권1호
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• pp.36-43
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• 1993

1. 벼의 생장율(生長率) 중묘(中苗)보다는 어린모를 이앙(移秧)할 경우(境遇)에 잡초(雜草)와의 경합해(競合害)가 컸으며, 이보다 직파(直播)에서는 더욱 치명적(致命的)이었으나, 담수(湛水) 및 건답직파재배간(乾畓直播我培間)에는 차이(差異)가 크지 않았다. 잡초경합(雜草競合)의 영향(影響)이 가장 컸던 시기(時期)는 이앙재배(移秧栽培)에서는 이앙후(移秧後) 10-11주(週), 담수직파(湛水直播)에서는 파종후(播種後) 11주(週), 건답직파(乾畓直播)에서는 파종후(播種後) 12주(週)에 해당하였다. 2. 벼와 잡초(雜草)의 군락구조(群落構造) : 관행이앙(慣行移秧)과 잡초(雜草) 기계이앙(機械移快)에서는 잡초(雜草)의 군락(群落) 점유율(占有率)이 늦어서 80cm이하(以下) 부위(部位)에서의 벼 공간점유율(空間占有率)이 특히 떨어지는 경향(傾向)이었으며 담수(湛水) 및 건답직파재배(乾畓直播我培)에서는 상하위(上下位)의 군락공간(群落空間)을 전체적(全體的)으로 잡초(雜草)가 점유(占有)하였다. 3. 벼와 잡초(雜草)의 초장신장(草長伸長) : 관행이앙재배(慣行移秧栽培)에서는 출수기(出穗期) 이전(以前)까지 벼의 초장(草長)이 상위(上位)에 있었으나 그 이후(以後)부터는 피와 올방개가 상위(上位)를 점하였으며, 중묘(中苗) 및 어린모 기계이앙재배(機械移秧栽培)에서는 출수기(出穗期)까지 벼와 잡초간(雜草間)에 상호경합적(且互競合的)인 관계(關係)에 있다가 이후(以後)에는 잡초(雜草)가 상위(上位)를 점하였다. 반면에 담수직파재배(湛水直播栽培)에서는 출수기(出穗期) 5주(週)까지 벼와 잡초간(雜草間)에 상호(相互) 경합적(競合的)이다가 6주이후(週以後)에는 피와 너도방동사니, 9주(週) 이후(以後)에는 올방개, 10주(週) 이후(以後)에는 알방동사니가 차례로 우위(優位)를 차지하였으며, 건답직파(乾畓直播)에서는 피가 생육(生育) 전기간(全期間)을 통하여 상위(上位)를 점하는 경향(傾向)이었다.