• Title/Summary/Keyword: 매자기

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Control of Perennial Weed Scirpus maritimus L. in Reclaimed Paddy Fields of West Seashore II. Physiological and Ecological Characteristics of S. maritimus (서해안 간척답에 있어서 다년생잡초매자기 방제에 관한 연구 제 2 보 매자기의 생리생태적 특성)

  • 양환승;전재철;문영희
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.1
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    • pp.64-73
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    • 1978
  • To gain a better understanding of the germination and growth of Scirpus maritimus, pot and field experiments were conducted to observe the development of new rhizomes and tubers, the growth rate of culms. and the germination behaviour of tubers of this perennial weed. Tuber placement, water depth, salinity and pH were also observed for their possible influence on the growth of S. maritimus.

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Control of Perennial Weed Scirpus maritimus L. in Reclaimed Paddy Fields of West Seashore I. Distribution of S. maritimus (서해안 간척답에 있어서 다년생잡초매자기 방제에 관한 연구 제 1 보 매자기의 분포)

  • 양환승;전재철;문영희
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.1
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    • pp.60-63
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    • 1978
  • The survey was carried out over an area representing about 29% of the reclaimed paddy fields of west and south seashore in Korea. Scirpus maritimus L. was heavily infested all over the reclaimed paddy fields. But the weed was scarcely found in double cropping fields cultivating barley at paddy after rice or in reclaimed paddy fields where the cultivation was taken a long time.

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Types of Weed Community in Transplanted Lowland Rice and Relationship between Yield and Weed Weight in Weed Communities (논 잡초의 군락형 종류와 군락형별 잡초발생과 수도수량과의 관계)

  • S. C, Kim;Keith, Moody
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.3
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    • pp.1-8
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    • 1980
  • Eight different weed community types growing in association with transplanted rice were identified in the experimental fields used in these studies. The Importance Value (LV.) of weed species growing in association with rice changed with time. The I. V. of Echinochloa glabrescens Munro ex Hook f. increased from 40 days after transplanting (DAT) until heading and then, decreased from heading to maturity of rice. However, the LV. of Monochoria vaginalis (Burm.) Pres!. and Echinochloa crus-galli ssp. hispidula (Retz.) Honda increased from 40 DAT to maturity while Scirpus maritimus L. decreased from 40 DAT. There was a high negative correlation between grain yield and weed weight at rice heading in all weed communities. The competitive ability of rice against weeds varied depending upon weed species. The highest yield decrease due to weed competition was obtained from the E. crus-galli ssp. hispidula-S. Maritimus community. Forty-two percent yield reduction was caused by competition of 100g dry weight of weeds per square meter of this community type at rice heading. The yield decrease for the same amount of weeds was 10% for the E. glabrescens community, 15% for the M vaginalis community and the M vaginalis-Scirpus supinus L. community and 21% for the M vaginalis-E. glabrescens-Fimbristylis littoralis Gaud.-S. maritimus community type.

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Control of Perennial Weed Scirpus maritimus L. in Reclaimed Paddy Fields of West Seashore III. Control of S. maritimus with Herbicides (서해안 간척답에 있어서 다년생잡초매자기 방제에 관한 연구 제3보 매자기의 약제에 의한 방제)

  • 양환승;전재철;문영희
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.1
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    • pp.74-80
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    • 1978
  • To identify new herbicides for the control of Scirpus maritimus and evaluate the performance of some promising herbicides for transplanted rice, field experiments were carried out in the reclaimed paddy fields.

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Identification of Sulfonylurea-Resistant Biotype of Scirpus planiculmis in Reclaimed Paddy Fields, Korea (한국 서산 간척지 논에서 Sulfonylurea계 제초제에 대한 저항성 새섬매자기 발생)

  • Park, Tae-Seon
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.332-337
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    • 2004
  • A suspected biotype of Scirpus planiculmis to be resistant to sulfonylurea(SU) herbicides was identified in Seosan reclaimed paddy fields in Korea, in 2004. The fields have been cultivated for monocultural rice production with wet-direct seeding method and continuously treated with SU-based herbicide mixtures for thirteen years since 1990. In greenhouse studies, 6 different SU herbicides, such as azimsulfuron, bensulfuron-methyl, cinosulfuron, ethoxysulfuron imazosulfuron and pyrazosulfuron-ethyl, completely controlled the Musan assession of Scirpus planiculmis at the recommended dose of each herbicide, however, the Seosan accession of S. planiculmis biotype was survived 20 to 45% even treated with 5 times higher dose of each recommended rate of all herbicides treated. The $GR_{50}$ values of 6 SU herbicides for Seosan accession of S. planiculmis were 47 to 100 times higher than those for Musan accession of S. planiculmis. The $I_{50}$ values pyrazosulfuron-ethyl to acetolactate synthase(ALS) extracted from Sesan and Muan accession of S. planiculmis were 409 nM and 0.8 nM, respectively. The $I_{50}$ value of Seosan was 511 times higher than that of Muan accession. These results suggested that the Seosan accession of S. planiculmis have strong resistant characteristics to 6 SU herbicides, respectively, indicating that resistance might be due to the alteration in the target site of ALS.