• 한국작물학회지
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• 제43권2호
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• pp.124-127
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• 1998

Since weedy rice problems have emerged with the recent advent of direct seeding cultivation in Korea, the establishment of effective control strategies for weedy rice is considered to be one of the urgent issues to be solved for widely practiced direct seeding rice cultivation. A three year experiment was conducted to investigate the occurrence pattern of weedy rice in four different rice cultivation practices: high ridged dry seeding, wet drill seeding, water seeding, and machine transplanting. The highest weedy rice occurrence of 11.0% was observed in high ridged dry seeding practice followed by 9.6% in wet drill seeding, 6.4% in water seeding practice, and 0.2% in machine transplanting practice, respectively. The same trend was observed when we examine the occurrence of contamination of panicle and rice grain by weedy rice. More contamination was observed in high ridged dry seeding than any other practices. It was also found that the possible emergence depths from the soil surface was deeper in both in ridged dry seeding and wet drill seeding practice (0-5 cm from the soil surface) than those in water seeding (0-4 cm), and machine transplanting practice (0-3 cm). The highest yield reduction of 19.5% was observed in high ridged dry seeding practice followed by 13.0% in wet drill seeding, 6.3% in water seeding practice. The reduction may have occurred to the competition between weedy rice and cultivated rice, These findings suggest that among the four cultural practices examined, the machine transplanting practice is the most effective method to control and reduce the weedy rice occurrence and weedy rice seed in soil.

• 한국작물학회지
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• 제45권4호
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• pp.232-236
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• 2000

To obtain a basic information on the development of effective control strategies for weedy rice in direct seeding rice cultivation, occurrence patterns of weedy rice as influenced by different cultural practices such as cultivation method, water management, seeding time, and tillage were investigated in field or pot experiments. High occurrence of weedy rice was observed in a continuous direct seeding paddy field as compared to machine transplanted one. Based on the percent of weedy rice panicle over three years trial, high ridged dry seeding was highest with 36.9%, followed by wet seeding with 30.9%, water seeding with 14.6% and machine transplanting rice with 0.8%, indicating 97.8% reduction in weedy rice occurrence by machine transplanting rice as compared with high ridged dry seeding. Germination of weedy rice was promoted to 83-94 % when rice panicle was flooded from September 30 to October 10 for 6 days and 74-88% for 9 days on October 20. Weedy rice occurrence was also substantially reduced by delayed seeding on June 10 and intensive tillage. The results suggest that machine transplanting rice be more effective cultural practice than flooding treatment, delayed seeding and intensive tillage when weedy rice problem occurs in direct seeded paddy field.

• Nutrition Research and Practice
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• 제1권1호
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• pp.8-13
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• 2007

Cooked rice is a staple food for Koreans which provides more than 60% of daily required energy. In 1960's, Koreans ate 600 g-800 g of cooked rice per meal and the energy obtained from cooked rice was almost more than 80% of the daily intake of energy. However, as the economy of Korea improved, the major industry has been shifted from agriculture to various manufacturing industries and the export of those products has been increased thus increasing the national income but decreasing the farming population and thus rice consumption have been decreased. It has been said that the decreased rice consumption is caused solely by decreased farming population but it can also be said that the decreased farming population is caused by decreased rice consumption. As the national income increases, the type of foods people consume have become diversified. Various processed foods such as convenience food or ready-to-eat food have been widespread, which are mostly made of wheat flour rather than rice.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1989년도 춘계 학술대회지
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• pp.64-65
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• 1989

• 한국작물학회지
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• 제46권6호
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• pp.429-433
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• 2001

경종조건에 따른 벼 이형주의 발생양상과 특성은 다음과 같다. 1.벼 이형주의 발생량은 종자의 자가 채종년수가 증가할수 록 많았고, 직파재배 포장에서 이앙재배 포장보다 2배 가량 많았다. 2. 재배벼의 재배포장에 장립적미와 단립적미를 인위적으로 산파 하였을 때 담수표면산파 재배에서 기계이앙 재배보다 발생량이 많고 간장이 길고 주당 유효경수가 많았으며, 장립적미가 단립적미보다 이런 특성들을 많이 지녔다. 3. 이앙재배 포장에서 이형주가 재배벼의 포기 밖에서 발생하는 비율은 농가관행재배의 경우 0∼6%인 반면, 장립적미와 단립적미를 인위적으로 산파하였을 때는 70.6∼91.1% 이기 때문에 농가포장에서 발생하는 이형주군의 대부분은 종자흔입에 의해 발생하는 것으로 보아진다.

• 한국작물학회지
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• 제24권1호
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• pp.1-10
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• 1979

In order to investigate the causes of epidemic out break of rice blast disease in 1978, investigations were undertaken in respect of climatic conditions, variety, cultural practice and plant pathology. During 1978, especially in August at heading time, it was higher temperature and humidity, higher frequency and amount of rainfall, lower amount of sunshine and solar radiation than less blast infested years. Nitrogen content in rice plant was higher than previous years. Acreage increase of semi-dwarf varieties brought about a result of proportional increase of new blast races which are able to infect the semi-dwarf varieties. It was concluded that those conditions mentioned above might have caused the result of severe neck blast disease in rice varieties in Korea, 1978.

• 한국토양비료학회지
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• 제35권4호
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• pp.216-222
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• 2002

무경운 재배가 논토양 온실가스 배출에 미치는 영향을 살펴보고자, 1998~2000년에 걸쳐 식질계 답토양에서 질소비종(요소, 유안, 완효성비료), 시비방법(전층시비, 표층시비), 유기물 시용(볏집시용, 무시용) 및 재배양식(건답직파, 중묘이앙) 등의 다양한 재배조건별 메탄가스 배출량을 경운과 무경운재배에서 조사하였다. 질소비종은 경운유무에 관계없이 유안시비구에서 메탄배출량이 가장 낮았다(요소 대비 26.6~41.1% 저감). 그러나 경운재배에 비해 수량이 낮은 무경운재배에서는 완효성 비료가 메탄배출량이 요소구에 비해 약간 적었고, 수량은 다른 질소비료 시비량이 80% 처리수준에서도 가장 높아 더 효율적인 비종으로 고려되었다. 시비방법에 따라서는 전층시비시 경운구에 비해 무경운구의 메탄배출량이 낮았으나 표층시비시에는 반대의 경향을 보였다. 볏짚 시용시에는 무경운에 의한 메탄배출 저감 효과가 강조되는 경향으로, 볏짚을 시용하지 않았을 때는 경운 대비 10.7% 저감되었고, $5000kg\;ha^{-1}$시용 시는 26.6% 저감되었다. 중묘이앙 재배시 무경운은 경운에 비해 26.6%의 메탄 배출 저감효과를 나타내었으나, 건답직파 재배시는 무경운에서 경운보다 메탄배출이 11.2% 증가하였는데 이는 건답직파시 논토양이 완전 담수되는 3엽기 이전에 경운에 의해 토양에 투입된 볏짚 중 상당한 양이 산화적으로 분해되어 $CO_2$로 대기중으로 배출되었기 때문이라 생각되었다.

• 한국잡초학회지
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• 제16권3호
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• pp.171-175
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• 1996

논에서의 물 관리(管理) 조건(條件), 이앙시기(移秧時期) 및 작부체계(作付體系)에 따른 피와 물달개비의 발생양상(發生樣相)을 비교(比較)하였다. 관개답(灌漑畓) 천수답(天水畓) 조건(條件)에서의 논 토양(土壞) 중 피 종자(種子) 저장량(貯藏量)은 큰 차이(差異)를 나타내지 않았으나, 물달개비 종자량(種子量)은 천수답(天水畓) 조건(條件)에서 약(約) 1.6배(倍)정도 많았다. 두 조건(條件)에서의 종자(種子) 분포(分布) 양상(樣相)은 표층(表層) 5cm 층위(層位)에 피는 전체종자량(全體種子量)의 50%가, 물달개비는 30%가 분포(分布)되었다. 물달개비는 두 조건(條件)에서 지표하(地表下) 25cm까지 분포(分布) 되었으나, 피는 지표하(地表下) 15cm까지만 분포(分布)되었다. 조기이앙시(早期移快時)에는 적기(適期)및 만기이앙시(晩期移快時)에 비하여 두 초종(草種)의 발생량(發生量)이 많았다. 벼 재배후(栽培後) 보리나 딸기와 같은 이모작(二毛作) 재배(栽培) 조건(條件)에서의 피나 물달개비의 발생(發生)보다는 벼만의 일모작(一毛作) 재배(栽培) 조건(條件)에서 발생량(發生量)이 현저하게 높았다.

• 한국잡초학회지
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• 제18권3호
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• pp.214-224
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• 1998

본 연구는 고소득작물인 인삼의 생산비 절감을 위한 새로운 재배법을 확립하기 위한 방안으로 인삼포의 잡초 발생을 억제시키는 allelopathic식물을 탐색, 선발하여 이용방안을 강구하기 위한 일련의 시험을 수행한 결과는 다음과 같다. 1. 볏짚, 귀리짚, 호밀짚 및 밀짚의 추출액을 인삼밭에 발생하는 주요 잡초인 털비름, 명아주, 조개풀, 바랭이, 피, 강아지풀 종자에 처리하여 발아율을 조사한 결과, 공시한 5종의 식물 영양체 추출액 모두 1% 농도 처리에서 발아 억제 효과가 크게 나타났으며, 특히 귀리짚 추출액은 공시된 모든 잡초종들에 대해 발아 억제 효과가 가장 컸다. 2. 볏짚, 호밀짚 및 밀짚의 추출액을 인삼 포장에 직접 처리한 결과, 3종의 식물 추출액 처리 모두가 무처리구인 대조구에 비해서 잡초생육이 억제되었으며, 공시한 3종의 식물 추출액 처리구에서 인삼의 근장, 근직경, 생체중, 건물중이 대조구에 비하여 좋은 것으로 나타났다.

• 한국작물학회지
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• 제46권1호
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• pp.6-11
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• 2001

In this lysimeter experiment, temporal changes of water percolation rate, irrigation requirement and ${No}_3$－-N leaching were investigated under different cultural practices that were no-till direct seeding on flooded paddy (NTDSF), till direct seeding on flooded paddy (TDSF), and transplanting. The highest water percolation rate of 3,001 l/$m^2$ was measured in NTDSF. Others were 2,551 l/$m^2$ and 2,210 l/$m^2$ in TDSF and transplanting. Water percolation rate in NTDSF and TDSF was increased by 36% and 15% compared to transplanting. Water percolation rates in all cultural practices were increased remarkably from the reproductive growth stage and relatively large amount of water loss through percolation was measured even after the reproductive growth stage. A total irrigation requirement was 3,469 l/$m^2$ in NTDSF and 2,898 l/$m^2$ in TDSF. That was equivalent to 45% and 21 % of increase compared to 2,389 l/$m^2$ in transplanting. The largest ${No}_3$－-N leaching through the entire rice growing period was 701 mg/$m^2$ in NTDSF and was followed by 494 mg/$m^2$ in TDSF and 465 mg/$m^2$ in transplanting. The ratios to the total amount of ${No}_3$－-N leaching at the vegetative growth stage, reproductive growth stage and ripening stage were 31 %, 41 % and 28% in NTDSF; 21 %, 48% and 31 % in TDSF; and 18%, 48% and 35 % in transplanting.