• 한국잡초학회지
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• 제30권3호
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• pp.206-214
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• 2010

The laboratory and green house studies evaluated the effect of three different environmental factors on the seed germination, seedling emergence and survival of four major weed species in coconut plantations, Mimosa pudica, Ureana lobata, Panicum maximum and Pennisetum polystachyon. Germination percentage of all the weed species was significantly reduced with increasing soil moisture stress, no germination was observed at -0.9 MPa. Germination of both grass seeds ranged from 8% to 25% and 10% to 45% as moisture stress decreased from -0.4 MPa to 0 MPa, respectively. In contrast, seeds of M. pudica, and U. lobata were moderately tolerant to soil moisture stress and best adapted to moist environment. All the weed species seeds germinated over a wide range of soil pH values with the highest germination occurring at pH 6. In all the species, seedling emergence was declined rapidly with increasing depth with the exception of U. lobata. Seedling emergence significantly declined when the duration of flooding was three days or longer in dicotyledonous weed species and two days or longer in monocotyledonous weeds. This study illustrates the adaptability of these weeds to different environmental conditions which would enable the development of management strategies to reduce their populations below economic threshold levels in coconut plantations.

• 한국작물학회지
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• 제44권1호
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• pp.32-37
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• 1999

The experiment was conducted to investigate emergence response of lowland weeds at different soil moisture contents, burying depths and upon changes in soil moisture. Rice germination was over 50% at all burying depths under aerobic condition, but the emergence rate of the soil surface placed seeds in saturated and flooded conditions decreased by 19% and 29%, respectively, as compared with that of aerobic condition. Rice seeds at burying depth of over 3 cm did not emerge at all. The emergence rate of Echinochloa crus­galli (L.) Beauv. in aerobic condition was lower than 30%, but the emergence pattern of E. crus galli (L.) Beauv. at different soil moisture contents and seeding depths was similar to that of rice. Emergence behavior of lschaemum rugosum Salisb., Ludwigia octovalvis (Jacq.) Raven and Sphenoclea zeylanica Gaertn. which are dominant lowland weed species in the Philippines also differed depending on soil moisture conditions and burying depths. lschaemum rugosum Salisb. emerged at all burying depths under aerobic condition, whereasLudwigia octovalvis (Jacq.) Raven emerged only at 0 cm deep under saturated and aerobic condition and Sphenoclea zeylanica Gaertn. at 0 cm deep under flooding condition. Weed seeds planted at 1, 3, and 5 cm deep in continuous flooded and saturated condition did not emerge at all, but upon a change of soil moisture condition from saturated to drainage (S$\rightarrow$D) and flooded to drainage (F$\rightarrow$D), grass weeds began to germinate again and the average emergence rate in S$\rightarrow$D and F$\rightarrow$D were 26% and 5% forE. crus­galIi (L.) Beauv., 9% and 8% forI. rugosum SaIisb., respectively. Weed seeds buried in soil in the pot showed great emergence at S$\rightarrow$D but did not emerge under continuous flooded condition. The diversity index accounting for dominance degree and occurrence aspect of weed, was the lowest at F$\rightarrow$D.

• 한국작물학회지
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• 제47권2호
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• pp.80-84
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• 2002

In spite of simple and cheap cultivation method, water broadcast-seeded rice demonstrates uneven and unstable seedling establishment per unit land area and requires more herbicide and labor-input for weed control. Three experiments were conducted in a phytotron at 18$^{\circ}C$ to evaluate the adaptability of seed-mat mulching cultivation technologies in water seeded rice for the uniform seedling establishment and the inhibition of weed occurrence without herbicide application. Five different kinds of mat with different mesh sizes and fabric properties were tested. The emergence of rice was the highest in Lawn-mat treatment, being comparable with the control, in which seeds were sown without mat. The Lawn-mat also exhibited the lowest mat tension. Mat tension may influence the emergence of rice. And once it was soaked in water, it didn't maintain its original shape any more. The emergence rate of rice was the lowest in Safer-mat treatment. In Lawn-mat treatment, which was the most effective for rice emergence in the first study, the differences of emergence and seedling establishment of rice depending on the seeding position (upper, beneath, and between mats) treatments were negligible, while they were higher in dry seeds than in pre-germinated seeds treatment. The emergence as affected by the kinds of mat also showed the same trend when tested using barnyard grass. Depending on the kinds of mat, the inhibition effect of weeds was the greatest in Safer-mat and the poorest in Lawn-mat. These results strongly suggest the possibility that the uniform seedling establishment and weed management without chemical could be achieved simultaneously by seed-mat mulching through the combination of effective mat for the emergence of rice and another efficient mat for the inhibition of weed occurrence. This possibility was also tested in the field.

• 한국잡초학회지
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• 제11권3호
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• pp.224-228
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• 1991

주요 밭잡초(雜草)의 복토심도(覆土深度), 산도(酸度), 시비(施肥)가 출아(出芽)에 미치는 영향(影響)을 알기위해 시험(試驗)을 수행(遂行)한 결과(結果)는 l. 밭토양(土壤)의 토심별(土心別) 잡초종자(雜草種子)의 분포(分布)는 10cm까지 58%가 존재(存在)하였고 40-45cm층(層)에도 2%가 분포(分布)하였으며 2. 복토(覆土)깊이에 따른 출아(出芽)에서 냉이는 표면(表面) 파종(播種)에서, 털비름, 개비름, 쇠비름, 명아주, 까마중은 3cm까지, 왕바랭이, 피는 7cm까지 출아(出芽)하였으며 강아지풀과 피는 7cm깊이에서도 각각(各各) 26, 40%의 높은 출아율(出芽率)을 보였다. 3. 공시(供試)된 잡초(雜草) 종자(種子)의 출아(出芽)는 pH 2.0-3.0의 탄산성(彈酸性)에서는 출아(出芽)가 저조했으나 피, 강아지풀, 명아주는 출아(出芽)했으며 pH 3.5-4.0 이상(以上)에서는 출아(出芽)에 큰 영향(影響)이 없었던 것으로 사료(思料)된다. 4. 토성간(土性間) 출아(出芽)는 토양(土壤)에서 왕바랭이, 냉이, 털비름, 개비름, 명아주, 피, 까아중, 강아지풀이 좋았으며 사양토(砂壤土)에서는 쇠비름, 바랭이가 좋았으나 시비(施肥) 유무간(有無間)에는 출아(出芽)에 영향(影響)을 주지 않았다.

• 아시안잔디학회지
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• 제2권1호
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• pp.59-64
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• 1988

This study was carried out to investigate the classification and the growing charicteristics of weed species in a newly formed lawngrass land. The results obtained are summarized as follows: 1)Weed population in a newly formed lawn field consisted of 30% of Gramineae, 15% of Compositae, and 12% of Leguminosae family. 2)Percentage of weed emergence between April and May was 39.4%. The same amount of weed emergence was observed at the period of September and October, where as the percentage was 21.2% at the period of March and April. 3)The population ratio of flowering date of weed species was in order of 48.5% July and August, 30.3% in May and July, 12.1% in March and April, and 9.1% in September and October. 4)Weed classification by life cycle showed 39.4% of biennials, 33.3% of annuals, and 27.3% of perennials. 5)Weed species were grouped according to the plant height. The ratios of each group were 33.3% of 20~40cm group, 27.3% of 40~60cm group, 24.2% of shorter than 20cm group, and 15.2% of taller than 60cm group.

• 한국잡초학회지
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• 제16권4호
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• pp.251-258
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• 1996

• 농업과학연구
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• 제38권2호
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• pp.191-198
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• 2011

Herbicidal effects and crop selectivity of aqueous leaf extracts of sorghum (Sorghum bicolor L.) were evaluated against several weed species for developing sustainable weed management in organic farming. Aqueous sorghum leaf extracts were highly phytotoxic to different weed species. No broadleaf weeds were germinated in the concentration of 5 fold or higher concentrated sorghum leaf extracts and 90% of seed germination was inhibited within that range in grass species. Sorghum leaf extracts strongly inhibited the growth of different weeds by pre-emergence and foliar applications in greenhouse condition. Foliar application of sorghum leaf extracts had a higher inhibitory effect than the pre-emergence application. Broadleaf weed species were more susceptible than grasses to the application of sorghum leaf extract in foliar applications than grasses. Galium spurium, Erigeron candensis, and Rumex japonicus were completely killed at the highest concentrated sorghum leaf extract both in pre-emergence and foliar application. Most broadleaf weed species were inhibited more than 80% at pre-emergence application at 50 fold concentrated sorghum leaf extract. G. spurium, E. candensis, R. japonicus, Eclipta alba, Plantago asiatica and Portulaca oleraeea were most susceptible to sorghum leaf extract in foliar application. Growth of most broad leaf weed species was suppressed by greater than 90% at 50 fold concentrated sorghum leaf extract. Most crop species were tolerant to sorghum leaf extract but shoot growth was slightly reduced by the application of 40~50 fold concentrated extracts, Sorghum leaf extract may used to control weeds in organic fanning without affecting the growth of crop.

• 한국잡초학회지
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• 제6권1호
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• pp.85-96
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• 1986

평지(平地) 성목원(成木園)과 경과지(傾科地) 유목원(幼木園)의 2개 과수원에서 Paraquat, Glyphosate, Oxyfluorfen, Napropamid 및 Ustinex 등 5종(種)의 과수원용 제초제를 공시하여, 잡초의 발생특성과 제초제를 인한 잡초생태형별(雜草生態型別) 과별(科別) 발생특성의 변동양상을 조사하고, 이를 근거로 잡초 및 제초제의 유사군분류(類似群分類)를 함으로써 새로운 제초제조합(除草劑組合) 모형화(模型化)의 다음 기초자료를 얻었다. (1) 과수원의 발생초종은 7생태형, 23과, 45종으로 일년생과 다년생의 분포는 각각 24종과 22종이었다. (2) 출현빈도가 높은 잡초종이 대부분 높은 현존량을 보임으로써 출현빈도가 잡초문제의 근간을 형성하는 경향이었다. (3) Paraquat은 속효 속재생성과 하계 일년생으로의 천이경향(遷移傾向)을, Glyphosate는 다년생 잡초의 탁월한 방제특성을, Napropamid는 잡초발생전의 토양 잔류성을, Oxyfluorfen은 하계일년생과 지중형 반지중형의 일부 다년생의 방제특성을 나타내는 각각의 장단점을 보였고, Ustinex는 혼합제로서의 다양한 초종 안정적인 제초효과를 보였다. (4) 제초제별 감수성반응에 따른 잡초를 분류한 결과, 발생빈도반응에서는 3군(群)과 8개(個) 단독과(單獨科)로 분류 되었다. 두 분류 기준에서 공통적으로 단독과(單獨科)로만 분류된 잡초는 산형과(科) 닭이장풀과(科) 화본과(科) 및 마디풀과(科)였다. (5) 제초제는 방제특성에서 상호간의 차이가 독특하게 컸으므로 유사군분류(類似群分類)가 되지 않는 경향이었으며, 비유사성(非類似性)이 큰 조합(組合)은 Paraquat이나 Glyphosate, Napropamid나 Glyphosate와 Napropamid나 Oxyfluorfen의 관계에 있었다.

• 한국잡초학회지
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• 제30권4호
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• pp.412-420
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• 2010

잡초는 농업생태계에서 경합에 의하여 막대한 피해를 입히며, 환경 및 인류의 부정적인 관심 때문에 잡초를 방제하기 위하여 사용되고 있는 합성 제초제에 대한 의존도를 줄이려는 노력이 전 세계적으로 이루어지고 있다. 이와 같은 관점에서 수수 추출물의 일종인 sorgoleone의 제초활성과 작물 선택성을 온실과 포장조건에서 검정하였다. Sorgoleone은 토양처리와 경엽처리에서 모두 높은 효과를 나타냈는데 화본과 잡초보다 광엽잡초에서 효과가 높았다. 온실조건에서 대부분 광엽잡초의 생장은 Sorgoleone $200\;{\mu}g\;ml^{-1}$에서 80%이상 억제되었고, 소리쟁이와 갈퀴덩굴은 완전히 고사되었다. 포장조건에서도 sorgoleone의 제초활성은 광엽잡초에 가장 우수하였고, 방동사니, 화본과 잡초 순이었다. 포장조건에서 잡초생장 억제정도는 전반적으로 온실조건보다 다소 낮은 경향이었다. 벼, 보리, 밀, 옥수수, 콩, 들깨, 토마토와 배추에서는 sorgoleone에 의한 생장억제는 거의 없었으나 상추와 오이는 생장이 억제되었다.

• 한국잡초학회지
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• 제8권1호
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• pp.33-36
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• 1988

Edinochloa glabrescens, Monochoria vaginalis, 및 Cyperus difformis 종자(種子)의 발아(發芽)에 미치는 비료시용(肥料施用)의 영향(影響)은 거의 없었다. 차광(遮光)은 E. glabrescens의 발아(發芽)를 감소(減少)시켰지만, 67%까지의 차광(遮光)은 M. vaginalis와 C. difformis의 발아(發芽)를 촉진(促進)시키는 경향이었다. E. glabrescens의 최고발아점(最高發芽點)은 무차광(無遮光), 31% 및 52% 차광조건하(遮光條件下)에서는 파종(播種) 후(後) 2 주에 나타났으나 67% 차광조건하(遮光條件下)에서는 뚜렷치 않았다. C. difformis의 최고발아점(最高發芽點)은 모든 차광조건(遮光條件)에서 파종(播種) 후(後) 6 주에서 8 주 사이에 나타났다.