• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.70-79
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• 1977

Perennial weeds which were grown in transplanted paddy field formed their tubers under shortday condition. Under short day treatment, the induction periods for tuber formation were different depending upon the weed species. 80% cut tubers of the weeds did not loose their developing ability perfectly. Emergence also affected by soil conditions and depths covered.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.26-35
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• 1993

Differences in weed occurrence was investigated among five types of rice (Oryza sativa L.) cultivation. The five types employed were three transplanting cultivations such as conventional hand transplanting, machine transplanting with 30-day-old seedling, and machine transplanting with 10-day-old seedling and two direct-seedings such as flood direct-seeded rice by pregerminated seed and dry direct-seeded rice by dry seed. Weed specie, occurred varied from 7 to 20, depending on the different cultivation types. Weeds were more diverse in transplanting with l0-day-old seedling than in other transplanting cultivations and in direct-seeding than in transplanting practice. Dominant weed species also varied with cultivation types. In transplanting cultivations Scirpus juncoides Roxb., Echinochloa crus-galli (L.) P. Beauv., and Eleocharis kuroguwai Ohwi were dominant, whereas occurrence of annual weeds such as Cyperus difformis L. and Monochoria vaginalis Presl. aside from the three weed species increased in direct-seeded cultivations.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.11 no.6 s.99
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• pp.65-74
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• 1990

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.46-53
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• 2018

This study was conducted to establish standard fresh weight data about the minimum amount of occurred weeds at untreated paddy fields, upland fields and orchard fields (including non-cultivated land) in 10 areas. The amount of occurred weeds in each area was compared fresh weight with dry weight. The average percentage for ratio of dry weight to fresh weight in paddy fields was concluded to be 14.8% of Echinochola crus-galli, 12.5% of annual weeds (including Echinochola crus-galli), and 13.9% of perennial weeds. The average percentage for ratio of dry weight to fresh weight in upland fields was concluded to be 20.1% of annual weeds and in orchard fields was concluded to be 18.4% of annual and perennial weeds. According to the research, standard fresh weight about the minimum amount of occurred weeds at untreated paddy fields was proposed to $210g\;m^{-2}$ of Echinochola crus-galli, $400g\;m^{-2}$ of annual weeds (including Echinochola crus-galli), and $220g\;m^{-2}$ of perennial weeds. Standard fresh weight about the minimum amount of occurred weeds at untreated upland fields was proposed to $250g\;m^{-2}$ of annual weeds and at untreated orchard fields was proposed to $550g\;m^{-2}$ of annual and perennial weeds.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.12 no.2 s.101
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• pp.47-51
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• 1991

비농경지는 농산물과 임산물을 생산하는 농경지,임야등을 제외한 모든 공지를 의미하지만 잡초방제를 대상으로 보면, 택지, 공업용지와 도로, 고속도로, 철도, 학교 운동장, 공원 등이 포함되는 공공용지로 구분할 수 있다. 농경지는 국가경제가 발전될수록 계속 잠식되어 택지, 공장부지 및 공공용지로 이용됨에 따라 비농경지 면적은 점차 확대되고 있으며 따라서 비농경지에 발생된 잡초방제의 필요성은 더욱 증대되리라 예상된다. 그러나 아직 우리나라에서는 체계적으로 비농경지 잡초의 분포, 방제법 등에 관한 연구가 거의 이루어지지 않고 있으며 잡초방제의 중요성과 관심도 매우 적은 실정이다. 따라서 비농경지에서 발생되는 잡초의 종류 및 피해양상, 잡초방제의 특성과 제초제를 이용한 잡초방제법을 정리하여 보기로 한다.

• Weed & Turfgrass Science
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• v.5 no.1
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• pp.1-4
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• 2016

The Rural Development Administration of Korea conducted a series of surveys of paddy weeds from 1971 to 2013 in approximately 10-year cycles and the results have been used for the efficient weed management of paddy fields. In 1971, annual weeds such as Rotala indica, Eleocharis acicularis f. longiseta, and Monochoria vaginalis were dominant. In 1981, the population of Echinochloa species decreased whereas broadleaf weeds such as M. vaginalis, Sagittaria pygmaea, and S. trifolia were dominant. In 1991, perennial weeds such as Eleocharis kuroguwai, S. pygmaea, and S. trifolia were dominant over annual weeds. In 2000, M. vaginalis was the most abundant species, followed by E. kuroguwai, Echinochloa species, and S. trifolia. In 2013, herbicide-resistant Echinochloa species and M. vaginalis were most dominant, followed by E. kuroguwai, Scirpus juncoides, and S. trifolia. It has been predicted that the prevalence of Echinochloa species will continue to increase and that perennial weeds will be more abundant than annual ones in the near future. The occurrence of herbicide-resistant weeds and exotic weeds will also increase due to global warming and changes in agricultural patterns.

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.247-255
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• 2016

This study was conducted to provide basic information for weed control by surveying the occurrence of weed species in turf sod production areas. Surveys of weed species occurred in turf sod production areas were conducted in Jangsung-gun, Jeonnam province from September 2014 to May 2016. Total 50 sites of turf sod production areas in two soil conditions were investigated. On the upland soil condition in turf sod production areas, 66 weed species in 27 families were identified and classified to 49 annuals and 17 perennials and on the paddy soil condition, 69 weed species in 22 families were identified and classified to 53 annuals and 16 perennials. Based on the importance values, the most dominant weed species on the upland soil condition in the first survey (September 2014) was Digitaria ciliaris (8.49%), followed by Erigeron annuus (7.94%) and Rorippa indica (6.56%). In the second survey (May 2016) was Oxalis corniculata (7.26%), followed by Capsella bursa-pastoris (6.21%) and Conyza canadensis (6.21%). Whereas the most dominant weed species on the paddy soil condition in the first survey (September 2014) was Erigeron annuus (9.52%), followed by Mazus pumilus (7.41%) and Cyperus iria (6.82%). In the second survey (May 2016) was Commelina communis (5.08%), followed by Alopecurus aequalis (5.08%) and Erigeron annuus (4.79%). This information could be useful for estimation of future weed occurrence and effective weed control methods in turf sod production areas in Jangsung-gun, Jeonnam Province.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.1
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• pp.61-69
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• 1977

The affect of perennial weeds to rice yield and rice growing was evaluated. Rice heading date was shortened 1-4days and rice culm length was shortened 5-10cm in heavy weed growing condition. The ratio of yield reduction were about 50% in Cyperus serotinus, about 57 in Potamogeton distinctus in both rice varieties and about 60% of Eleocharis kuroguwal in heavy perennial growing condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.20-23
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• 1976

Distribution of underground organs of perennial weeds in soil and ecological control measure were evaluated. Tubers of Cypers serotinus and Sagittaria pygmaea were mostly presented in a shallow depth of 0 to 5cm, however, Potamogeton distinctus's bulbs and Eleocharis kuroguwai's tubers were distributed in the soil at 10 to 20cm. A 20cm autumn plowing was, to some extent, effective to reduce Potamogeton distinctus. The herbicide, avirosan at 3kg/10a alone, was extremely effective in controlling Potamogeton distinctus.

• Agrochemical news magazine
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• v.14 no.5 s.116
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• pp.17-23
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• 1993