• 한국잡초학회지
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• 제12권3호
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• pp.223-229
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• 1992

우리 나라의 벼 재배형태(栽培形態)는 단기적(短期的)으로 많이 변하고 있으며, 특히 재배시기(栽培時期)는 빨라지며 시비량(施肥量)이 증대(增大)되었다. 논에서 잡초발생(雜草發生)은 재배시기(栽培時期)가 빠르고 직파(直播)함에 따라 잡초발생(雜草發生)이 많으며, 직파(直播)에서도 산파(散播)보다 조파(條播)에서 많았다. 직파(直播)에서는 물관리(管理)를 포화상태(飽和狀態)로 유지(維持)하는 것이 심수관개(深水灌漑) 보다 잡초발생량(雜草發生量)이 많고 잡초발생(雜草發生) 구성(構成)도 포화상태(飽和狀態)의 관리(管理)가 다년생(多年生) 잡초(雜草)의 발생(發生)을 줄이고 일년생(一年生) 잡초(雜草)의 발생(發生)을 촉진(促進) 증대(增大)시켰다. 재배형태(栽培形態)가 이앙재배(移秧栽培)에서 직파재배(直播栽培)를 함에 따라 다년생(多年生) 잡초(雜草)의 비율(比率)이 낮아지고 일년생(一年生) 잡초(雜草)의 발생(發生)이 종류(種類)나 량(量)에서 크게 높아졌다. 직파재배(直播栽培)에서 잡초(雜草)의 경합력(競合力)은 커서 초장(草長)의 경우는 생육기간(生育期間)동안 계속 벼보다 컸으며, 이에 따라 벼는 전체(全體) 군락(群落)의 중하부(中下部)에 위치(位置)하고 있었다. 따라서 이앙재배(移秧栽培)보다 직파재배시(直播栽培時) 잡초(雜草)의 문제(問題)는 매우 컸으며, 또한 잡초발생(雜草發生)의 양상(樣相)이 어느 특정재배(特定栽培) 조건(條件)에 따라서 크게 차이(差異)가 있고 변화(變化)될 수 있어 현재(現在)와 같은 단순(單純)한 잡초방제(雜草防除) 체계(體系)로는 잡초문제(雜草問題)를 해결(解決)하기 어려울 것으로 판단(判斷)된다.

• 한국잡초학회지
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• 제31권1호
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• pp.1-7
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• 2011

제초를 위한 화경수누법, 즉 화누법은 고대 중국의 "제민요술"에서 유래되어 16~18세기에는 우리나라의 "위빈명농기" "농가집성" "과농소초"에 옮겨진 제초법이다. 직파된 벼논에서 벼와 잡초종들이 입모된 이후에 군락 초관위로 불놓아 태워진 연후에 물을 관수하므로써 잡초를 제거하고 선별적으로 벼를 안전하게 살려 재생시키는 방법이다. 불로 태우는 대신에 이에 걸맞는 비선택성이며 비이행성인 제초제(예, paraquat, oxyfluorfen 등), 또는 방사선 등을 처리하여 손쉽고 안전하게 제초문제를 해결하는 방식으로 응용할 수 있을 것이다.

• 한국물환경학회지
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• 제21권5호
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• pp.477-483
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• 2005

Anammox (Anaerobic Ammonium Oxidation) bacteria is recently discovered microorganism which can oxidize ammonium to nitrogen gas in the presence of nitrite under anaerobic conditions. The anammox process can save an energy for nitrification and need not require a carbon source for denitrification, however, the start-up periods takes a long time more than several months due to the long doubling time (approximately 11 days). In order to find the effects of seeding microorganisms, hydrazine, and nitrite concentration on the enhancement of the anammox activity, five kinds of microorganisms were selected. Among the several kinds of seeding microorganisms, the granule from acclimated microorganisms treating high concentration of ammonia nitrogen (A-1) and sludge from piggery wastewater treatment plant (A-2) were found to have a high anammox activity. In the case of A-1, the maximum nitrogen conversion rate represented 0.4 mg N/L-hr, and the amount of nitrite utilization was high compared to those of other seeding microorganisms. The A-4 represented a higher nitrogen conversion rate to 0.7 mg N/L-hr although the ammonium concentration in the serum bottle was high as 200 mg/L. Meanwhile, the anaerobic granule from UASB reactor treating distillery wastewater showed a low anammox activity due to the denitrification by the remained carbon sources in the granule. Hydrazine, intermediate product in anammox reaction, enhanced the anammox activity by representing 1.4 times of nitrogen gas was produced in the test bottle than that of control, when 0.4 mM of $N_2H_4$ was added to serum bottle which contains 5 mM of nitrite. The high concentration of nitrite (10 mM) resulted in the decrease of the anammox activity by showing lower production of nitrogen gas compared to that of 5 mM addition of nitrite concentration. As a result of FISH (Florescence In-Situ Hybridization) experiment, the Amx820 probe showed a more than 13% of anammox bacteria in a granule (A-1).

• 한국잡초학회지
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• 제32권3호
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• pp.280-284
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• 2012

벼 무경운 직파 재배는 노동력을 절감하고 쟁기 및 로타리 경운을 생략함으로서 에너지를 절약하는 이점이 있다. 또 토양 및 토양수분을 보전하고 논 표층에 토양유기물을 축적시키는 장점이 있다. 이는 벼 무경운 재배 논에서 동계에 많이 발생하는 뚝새풀로 인함이다. 본 시험에서 벼 무경운 재배를 한 논에서 동계에 뚝새풀이 많이 발생하였는데, 피복정도가 식양질에서 97.6%, 사양질에서 95.2%로 아주 심하게 발생을 하였다. 이로 인해 벼룩나물, 황새냉이, 개갓냉이, 선씀바귀 등 월년생 잡초나 숙근초의 발생이 줄어들었으며, 그리고 봄철 일찍 발생하는 1년생 잡초 좀명아주, 여뀌 뿐 아니라, 관개 후 논에서 발생하는 피, 알방동산이, 물달개비, 밭뚝외풀 등의 1년생 하계 논잡초들의 발생도 줄어들었다. 결론적으로 벼 무경운 직파 시 동계에 발생하는 뚝새풀로 인해 하계 논잡초 발생을 관리할 수 있는 이점도 있는 것이다.

• 멤브레인
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• 제29권5호
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• pp.263-275
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• 2019

본 연구에서는 종결정 크기, 종결정 코팅양, 수열 용액 숙성시간을 조절함으로써 분리층 두께가 제어된 모데나이트 제올라이트 분리막을 제조하고, 분리층 두께가 투과증발 물 투과유속에 미치는 영향을 90 wt.% 에탄올 수용액에서 고찰하였다. 유성 밀을 이용해 종결정을 분쇄시켜 20~30 nm 크기의 종결정을 제조하였고, 진공여과코팅 중에 종결정 용액의 농도와 통과된 양을 바꿔주면서 코팅양을 조절하였다. 제조된 분리막은 분리층 두께가 얇을수록 더 높은 물 투과유속을 나타내었으며, 약 $4{\mu}m$ 두께를 갖는 분리막의 경우, 760의 높은 물/에탄올 선택도와 $1.0kg/m^2h$의 높은 물 투과유속을 나타내었다. 이는 나노크기 종결정을 사용하여 $4{\mu}m$ 두께로 분리층을 얇게 만들었기 때문으로 판단된다. 따라서 본 연구로부터 종결정의 크기와 진공여과 코팅양, 수열 용액 숙성시간을 조절하는 것은 분리 층의 두께를 효과적으로 조절할 수 있는 방법임을 알았다. 또한, 모데나이트 제올라이트 분리층의 두께를 얇게 하는 것이 분리막의 물 투과유속을 증진시키는 중요한 방법임을 확인하였다.

• 한국초지조사료학회지
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• 제2권2호
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• pp.1-15
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• 1981

In reviewing of the literature concerning agronomic practices on intensive pasture establishment the following suggestions were made : (1) The seedbed preparation should be involved physical manipulation of the soil tilth and consolidation of the soil by harrows and heavy roller. (2) In terms of methods of sowing, drilling favours the first and broadcasting the second however, the apparent superiority of band sowing over the above conventional methods is to reduce the direct toxic chemical effects from fertilizers to germinating seeds. (3) The most satisfactory seeding depth for grasses and legumes is commonly agreed to be approximately 1.3cm and seeding depth greater than 2.5cm seems to be generally detrimental. (4) Autumn and spring are most common sowing periods for grasses and legumes, however, early autumn being the most generally favoured, particularly in areas not subject to severe winter kill. (5) Select nurse crop species or cultivars which make Bess demands on light, nutrients and water, and lower seed rates should be used. (6) Seeding mixtures should be simple rather than complex and aggressive species should be included to a minor extent.

• 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.

• 한국작물학회지
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• 제42권4호
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• pp.473-482
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• 1997

Temperature, humidity and wetness duration were monitored for fully developed paddy rice canopies with 3 different structures induced by the seeding method(puddled-soil drill seeding, DS ; hand broadcasting, HB ; machine broadcasting, MB). Within-canopy air temperature averaged over "clear sky" hours during the study period(maximum tillering through heading) was lower than the screen temperature at a nearby standard weather station, especially in the night. The same trend was true for "overcast sky" hours except the diurnal distinction. Vapor pressure within the canopy was high during the daytime and low in the night, making the daytime deviation from outside the canopy more significant on clear days. Under the overcast sky, the canopy maintained a steady 5 to 10％ higher vapor pressure than the outside regardless of day or night. Daily maximum temperature was observed to be higher within the canopies with more leaf mass, making MB the highest, HB the lowest, and DS in between. Relative humidity was over 90％ in the night and dropped to 70％ in the mid-afternoon, but vapor pressure within the canopy was highest at around 13:00 LST. Dew point depression was lowest and, combined with the temperature, the relative humidity was highest in HB. Mean period of wetting duration was in the order of DS＞HB＞MB, while the dew point depression was greatest in DS.

• 생물환경조절학회지
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• 제16권1호
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• pp.62-66
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• 2007

시금치 수경재배에 적합한 육묘배지 선발과 육묘 플러그 트레이 크기, 육묘 플러그 트레이 셀(cell)당 종자수 조절로 안정 공정 육묘생산을 위한 실험을 수행하였다. 수경재배 육묘배지에 따른 입모율과 유묘의 생육특성을 조사한 결과 입모율은 보습성이 좋은 입상암면 >입상암면+펄라이트 혼용배지>코코피트>펄라이트>우레탄 스펀지 순으로 나타나 우레탄 스폰지의 입모율이 가장 낮았다. 육묘 플러그 트레이 셀당 종자수에 따른 엽 면적은 종자수가 많을수록 적어지고, 셀당 생체중은 2립(12.5g)에 비해 4립(33.9g)이 무거웠다. 따라서 셀당 종자수가 적으면 식물체 1개 체중은 증가되지만 전체 셀당 생체중은 감소되는 경향을 나타내었다. 수량은 셀당 2립 파종 $10,200kg{\cdot}ha^{-1}$ 비해 4립 파종 $14,910kg{\cdot}ha^{-1}$으로 46% 증가되었다.

• 한국식품영양학회지
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• 제31권4호
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• pp.502-510
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• 2018

To begin with, this study identified and reviewed the proximate compositions, quality and physicochemical characteristics of three Korean cowpea (Vigna unguiculata L. Walp.) cultivars grown in two different seedling periods. The proximate compositions of the cowpea showed significant differences according to three cultivars (Seowon, Yeonboon and Okdang) and two different seeding periods (5 June and 5 July). Through this lens, the lightness, redness and yellowness of the cowpea cultivars increased slightly during the 5 July cultivation compared to the 5 June cultivation. This brings us to understand that the water binding capacity, water solubility index, and swelling power were significantly different among the cultivars. In this case, the water binding capacity of the cowpea was 108.87~143.19%, and decreased during the 5 July cultivation compared to the 5 June cultivation. As shown, the total polyphenol and flavonoid contents of cowpea showed significant difference according to cultivars. In this case, the total polyphenol content of 5 June and 5 July cultivation on the Seowon 4.17 and 4.12 mg GAE/g, respectively. In these terms, the DPPH radical scavenging activity of cowpea showed a significant difference according to the cultivars, and the Yeonboon and Okdang increased slightly during 5 July cultivation. The ABTS radical scavenging activity of the cowpea showed significant difference according to the cultivars, and all cultivars decreased slightly during the 5 July cultivation. In other words, the phenol contents and radical scavenging activity differ measurable depending on the cultivars and seeding periods. Therefore, it is necessary to study the proper cultivar and seeding time considering the environment of the applicable cultivation area.