• The Plant Pathology Journal
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• 제34권6호
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• pp.490-498
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• 2018

Panicle blight and seed rot disease caused mainly by Burkholderia glumae and Burkholderia gladioli is threatening rice cultivation worldwide. The bacteria have been reported as seed-borne pathogens from rice. Accurate detection of both pathogens on the seeds is very important for limiting the disease dissemination. Novel primer pairs targeting specific molecular markers were developed for the robust detection of B. glumae and B. gladioli. The designed primers were specific in detecting the target species with no apparent cross-reactions with other related Burkholderia species at the expected product size. Both primer pairs displayed a high degree of sensitivity for detection of B. glumae and B. gladioli separately in monoplex PCR or simultaneously in duplex PCR from both extracted gDNA and directly preheated bacterial cell suspensions. Limit of detection was as low as 0.1 ng of gDNA of both species and $3.86{\times}10^2cells$ for B. glumae and $5.85{\times}10^2cells$ for B. gladioli. On inoculated rice seeds, the designed primers could separately or simultaneously detect B. glumae and B. gladioli with a detection limit as low as $1.86{\times}10^3cells$ per rice seed for B. glumae and $1.04{\times}10^4cells$ per rice seed of B. gladioli. The novel primers maybe valuable as a more sensitive, specific, and robust tool for the efficient simultaneous detection of B. glumae and B. gladioli on rice seeds, which is important in combating rice panicle blight and seed rot by early detection and confirmation of the dissemination of pathogen-free rice seeds.

• 한국작물학회지
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• 제44권2호
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• pp.134-137
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• 1999

An experiment was carried out to determine the effects of priming and growth regulator treatment of seeds on the emergence and seedling growth of rice, Oryza sativa L. (cv. 'Ilpumbyeo'). Normal seeds were primed in a -0.6 MPa polyethylene glycol solution at 15$^{\circ}C$ for four days with air-bubbling. Then both primed and non-primed seeds were soaked in water, 100 ppm GA$_3$, 2 ppm ABA, and 10 ppm kinetin solutions for 24 hours. The seeds were planted in soil at 3 and 5 cm depths and allowed to germinate in a growth cabinet at 2$0^{\circ}C$. Generally, the emergence rate at the 3 cm seeding depth was higher and emerged faster compared with the 5 cm seeding depth. The emergence rate of primed seeds was higher and emerged faster compared to non-primed seeds. GA$_3$ and kinetin treatments were the most effective to improve the emergence rate of non-primed seeds. Coleoptile length at the 5 cm seeding depth was longer than that at the 3 cm seeding depth. Leaf number, plant height, and root length of primed seedlings were higher compared with non-primed seeds. GA$_3$ promoted the elongation of plant height and mesocotyle length.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.119.2-120
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• 2003

Seed-borne fungal pathogens on rice seeds were investigated in order to evaluate their effect on rice grain quality. Rice seeds of two cultivars, Ilmibyeo and Daesanbyeo were collected from 27 areas of Korea and the fungal parasites on seeds were isolated by using a blotter method. Isolation frequency and number of species were varied from collection areas of seed samples. A total 13 species of fungi were identified from the seeds. Among them, Altemana alternata was the most frequent over the country. Bipoiaris oryzae most commonly from Gyeongbuk and Jeonbuk, Alternaria padwickii from Jeonbuk, and Nigrospora oryzae from Choongnam. However Bipolaris. oryzae, Alternaria padwickii, and Nigrospora oryzae were the most frequently isolated fungi from Gyeongbuk and Jeonbuk, and Chungnam, respectively. B. oryzae, A. alternata, A. padwickii, and N. oryzae were dominants on Ilmibyeo showing 10.3％, 10.2％, 5.2％, and 5.2％ infection rate, respectively. While, N. oryzae, A alternata, and Cladosporium sp. were most frequently isolated fungi from Deasanbyeo revealing 15.1％, 9.6％, and 7.5％ infection rate, respectively. These fungi inhabiting on hulls or endosperms of rice seed might be considered as potential factors decreasing rice grain quality. Further investigation of the fungi on grain rice quality are undergoing.

• 현장농수산연구지
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• 제21권2호
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• pp.77-86
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• 2019

To determine none top soil covering in rice seedling nursery method for the sparse machine transplanting, four different sowing methods were tested. Shoot and root length, fresh weight, leaf number and color using leaf color chart(LCC) and SPAD were collected as the data comparison of methods. The seedling height showed the highest growth according to the conventional (230g seed rate of pre-emerged seeds and top-soil covering) > high sowing density 1 (290g seed rate of pre-emerged seeds and top-soil covering) ≥ high sowing density 2(290g seed rate of pre-emerged seeds and none top-soil covering) > high sowing density 3(290g seed rate of iron-coated seeds and none top-soil covering). There was any statistical difference between groups in root length, leaf number, LCC, and SPAD values. Thus, a high sowing density of 290g for rice nursery seedling box was recommended to the sparse machine transplanting in rice cultivation with the none top-soil covering method, enabling convenient handling in transportation and machine transplanting work.

• 한국작물학회지
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• 제43권1호
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• pp.1-5
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• 1998

Experiments were carried out to find out the optimum water potential, temperature, and duration for the priming of rice seeds, Oryza sativa L. (cv. Ilpumbyeo) for better germination at sub-optimal temperatures. Seeds were primed in 0, -0.2, -0.4, -0.6, -0.8, and -1.0 MPa PEG (polyethylene glycol) solutions at $25^{\circ}C$. The optimum water potential for seed priming, the highest water potential at which rice seeds did not germinate, was -0.6 MPa. To find out optimum priming temperature and duration rice seeds were primed in -0.6 MPa PEG solution and 0 MPa (water as a control) for various durations at 15 and $25^{\circ}C$ and the seeds were germinated at 17, 20, and $25^{\circ}C$. Considering germination rate and speed, the optimum priming time in water (0 MPa) was 4 days at 15$^{\circ}C$ and 1 day at $25^{\circ}C$, while 4 days was the optimum priming time in a -0.6 MPa PEG solution, regardless of the priming temperature. Priming reduced the actual time of germination, especially at sub-optimal temperatures. Priming did not affect germination rate in -0.6 MPa PEG solution at 15$^{\circ}C$, but overpriming reduced the final germination rate in water at 15$^{\circ}C$ and in -0.6 PEG solution at $25^{\circ}C$. Total sugars and $\alpha$-amylase activity induced during the seed priming were negatively correlated with the final germination rate and there was no noted relationship with the speed or uniformity of germination.

• 한국작물학회지
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• 제62권1호
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• pp.9-15
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• 2017

본 연구는 벼 무논 및 담수직파 시 입모향상을 위해 철분코팅종자와 일반종자에 대한 발아특성 및 담수깊이에 따른 초기 입모영향을 구명한 결과를 요약하면 다음과 같다. 철분코팅종자는 일반종자보다 발아초기에는 발아율이 높았으나 후기에는 일반종자의 발아율과 비슷하였다. 그 결과 철분코팅종자가 일반종자에 비해 발아속도가 빠르고 평균 발아일수가 짧았다. 철분코팅종자를 상온종자창고에 보관시 1년이 지난 후 발아율은 보관당시보다 15.3~21.6% 감소되어 가능한 철분코팅 종자는 1년 이내에 사용하는 것이 바람직하였다. 또한 담수직파조건에서 철분코팅 종자는 일반종자에 비해 깊은 수심에도 출아율이 높고, 뜬묘비율도 낮을 뿐만 아니라 모 충실도가 높아 담수직파 시 철분코팅종자를 사용하는 것이 초기입모를 향상시킬 수 있는 방법이 될 수 있다.

• 현장농수산연구지
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• 제19권1호
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• pp.119-128
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• 2017

벼 직파재배 유형별(철분 무논점파, 복토 무논점파, 철분 담수산파, 기계이앙-대조구) 생육 및 수량 비교를 위한 포장시험 결과는 다음과 같았다. ① 벼 직파재배 유형별 출아일수는 8~9일 소요되었으며, m²당 입모수는 철분 무논점파>복토 무논점파>철분 담수산파>관행 담수산파 순으로 많았다. 결주율은 복토 무논점파 2.7%, 철분 무논점파 2.0%로 비교적 낮게 나타났다. ② 주요 벼 생육시기별 초장 생육은 무논점파법이 담수산파에 비하여 생육초기 초장이 다소 높게 경과되었으나 파종 후 75일에는 관행 담수산파를 제외한 벼 재배방법에서 통계적 유의성 차이가 인정되지 않았다. ③ 벼 경수 생육은 철분 담수산파에서 가장 높게 경과되었으며 철분 무논점파, 관행 담수산파, 복토 무논점파, 기계이앙 순이었다. ④ 벼 수량구성요소에서 m²당 수수는 철분 담수산파>철분 무논점파>관행 담수산파>복토 무논점파>기계이앙 순으로 많게 나타났다. ⑤ 벼 직파재배 유형별 쌀 수량은 철분 담수산파 640kg/10a, 철분 무논점파 619kg/10a, 기계이앙 601kg/10a, 관행 담수산파 599kg/10a, 복토 무논점파 544kg/10a 순으로 높게 나타났다. ⑥ 현미품위는 완전립 비율이 복토 무논점파 65.8%, 철분 담수산파 65.4%, 철분 무논점파 62.7%, 기계이앙 62.3%, 관행 담수산파 62.2% 순으로 높았다.

• 한국작물학회지
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• 제60권3호
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• pp.282-292
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• 2015

최근 소비자들의 건강에 대한 관심이 증가함에 따라 건강기능성 성분이 다량 함유 되어 있는 유색벼 품종의 안전 육묘를 위한 종자의 발아특성, 적정 침종기간 및 적정 파종량을 구명하기 위한 시험결과는 다음과 같다. 1. 현미색이 흑색인 조생흑찰 및 신명흑찰은 비중이 1.0이하의 물에 뜨는 종자가 85.7~86.3%로 대부분을 차지하였고, 비중이 1.06이상 충실한 종자 비율은 1.0~1.3%로 다른 흑미에 비해 상대적으로 낮았다. 한편 신토흑미, 흑진주, 흑설, 흑남, 흑광은 비중이 1.0이하가 15.3~43.7%, 1.0~1.06이 24.6~39.4%, 1.0이상이 25.5~55.7%로 다양한 무게의 종자가 분포해 있었다. 그러나 적미인 홍진주, 적진주, 건강홍미는 일반벼인 일미벼와 같이 충실한 종자인 1.06이상의 비율이 84.0~86.6%로 높았고, 반면 비중이 1.0~1.06은 2.5~4.1%, 비중이 1.0이하의 물에 뜨는 종자의 비율은 9.3~12.1%로 낮았다. 2. 흑미는 일반적으로 물온도에 관계없이 발아율이 적미보다 낮았고 발아속도가 느렸으며 평균발아일수도 길었고 수분흡수율도 낮았다. 그 결과 80%이상 발아하기 까지 침종기간이 적미나 일반벼 보다 2~4일 가량 더 결렸다. 이것은 흑미는 비중이 1.0이하의 가벼운 종자가 적미보다 훨씬 높았기 때문이다. 3. 상자육묘시 흑미의 출아율은 10일묘에서 75.2~82.2%, 30일묘에서 85.3~90.9%로 적미보다 10일묘에서는 4.5~8.0%, 30일묘에서는 0~3.3% 낮았는데 이것은 미출아율 종자가 많았기 때문이었다. 4. 기계이앙 육묘시 유색벼의 안전 육묘를 위한 적정 파종량은 관행 일미벼 어린모 및 중묘의 상자당 성묘개체수를 기준으로 흑미의 경우 어린모는 200~220g, 중묘는 110~130g이었고 적미는 일반벼와 같이 어린모 220g, 중묘 130g이었다.

• 한국작물학회지
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• 제43권4호
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• pp.214-222
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• 1998

These experiments were conducted to investigate water uptake, electrical conductivity, germination percentage, seedling growth, and seedling establishment rate in direct seeding cultivation of rice. The rice seeds of six japonica type varieties were coated with 12 kinds of polymers in a standard concentration of 0.2% using seed coating machine. The water absorption of the polymer-coated seeds under saturation conditions was not different among varieties, and was the highest in kulcel, maltrin, and waterlock on the polymer-coated seeds. The electrical conductivity with waterlock (55.0 $\mu scm^{-1}g^{-1}$) was higher than the control plot (45.6 $\mu scm^{-1}g^{-1}$) and other treatments. The germination of the polymer-coated seeds was 95.9% at control plot, 92.7% at low temperature and 35.7% at high temperature. The total dry weight of seed decreased in the order of low temperature, control plot, and high temperature, and was effective in pvp (polyvinyl pyrrolidone), opadry, and sacrust. The seedling establishment rate in direct seeding cultivation ranged from 74.9 to 81.0% in flooded paddy surface, and ranged from 64.7 to 76.6% in dry paddy. In both cases, it decreased in the order of early, medium and medium-late varieties, but was enhanced in daran 8600, sepirect, and sacrust. According to this study the recommended polymers for direct seeding cultivation of rice are daran 8600, sepirect, and sacrust.

• 한국약용작물학회지
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• 제19권4호
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• pp.233-237
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• 2011

This study was carried out to investigate the seedling establishment and yield of direct-sown Platycodon grandiflorus seeds cultured by three ridge width, 0.4, 0.8, and 1.2 m and four mulching materials, rice straw, rice bran, black plastic film, and no mulching in upland. Seedling establishment rate (70%) was the highest in rice straw mulched plot of 500 seeds/$m^2$ sowed and root yield after one year was also the highest in rice straw mulched treatment and followed by rice bran, no mulching, and black plastic film treatment. In this result, ridge width 120cm and rice straw mulching combined treatment was best for getting the highest seedling establishment ratio and seedling numbers per area. However, ridge width and mulching materials should be considered soil moisture content and weed population for saving labor cost.