농촌진흥청에서는 1971년부터 2013년까지 10년 주기로 논잡초 발생 분포조사를 실시하여 논잡초의 효율적인 관리에 이용되고 있다. 1971년에는 주로 마디꽃, 쇠털골, 물달개비 등 일년생잡초가 많이 발생된 반면에, 1981년에는 피의 발생이 줄어들고, 물달개비와 올미, 벗풀 등의 광엽잡초가 우점하였다. 1991년에는 일년생잡초 보다는 올방개, 올미, 벗풀 등과 같은 다년생잡초가 많았다. 2000년에는 물달개비가 가장 많이 발생되었고 그 다음으로 올방개, 피, 벗풀 등이었다. 2013년에는 제초제 저항성잡초인 피와 물달개비가 최우점하였으며, 올방개, 올챙이고랭이, 벗풀 등의 순이었다. 향후 논잡초 발생은 피의 발생량이 계속 증가할 것이고, 다년생잡초가 일년생잡초보다 발생비율이 높아질 것으로 예상된다. 또 이러한 추세는 기후변화와 재배방식 등의 농업패턴 변화로 제초제 저항성 잡초와 외래잡초의 발생이 증가될 것이다. 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.

4-HPPD저해 제초제에 의한 주요 벼품종의 약해반응과 약제반응에 관여하는 유전자(HIS1) 특성을 구명하기 위해 본시험을 수행하였다. Benzobicyclon 액상수화제 처리에 Japonica 품종인 상주벼에는 백화증상의 약해증상이 발생하지 않았으며, Japonica 품종임에도 불구하고 삼백벼에서는 기준량에서는 2-3, 배량에서는 3-4의 백화증상의 약해가 발생하였으며, 산들진미, 금영 품종에서는 3-4 및 4-5의 약해증상을 보였다. 또한 Indica 품종인 IR-8 품종에서는 기준량에서 3~5, 배량에서는 4~6의 가증 심한 약해증상을 보였다. 4-HPPD저해 제초제애 대해서 약제반응에 관여하는 HIS1 유전자 보유여부를 확인하기 위해 일반계 품종인 상주벼와, 삼백벼, 산들진미, 금영과 통일형 품종인 IR-8품종으로부터 저항성 표적유전자와 동일 HIS1 유전자를 분리하였다. 각 품종별 HIS1유전자를 PCR등을 통해 염기서열을 확인한 결과 HIS1 유전자는 생태형에 상관없이 시험한 5품종 모두에서 HIS1유전자를 보유하고 있는 것으로 확인되어, 본 유전자로 HPPD 약해 발생 유무를 검증할 수 없음이 확인되었다. This study was conducted to determine phytotoxicity of domestic rice varieties and characteristic of sensitive gene involved in herbicide reaction of 4-HPPD (4-hydroxy phenylpyruvate dioxygenase) inhibiting herbicides. The five rice varieties were grown for 2 to 3 leaf stage on seedling trays and then transplanted into plastic pot: 4-Japonica type (Sangjubyeo, Sambaekbyeo, Sanduljinmi and Kumyoung) varieties and 1-Indica type variety (IR8). We trialled standard (14 g a.i. $10a^{-1}$) and double fold (28 g a.i. $10a^{-1}$) dose of benzobicyclon treatment at 10 days after transplanting in order to investigate phytoxicity. The Japonica-type Sangjubyeo showed no rice injury but Indica-type IR8 show 4-5 (standard) and 5-6 (double fold) phytoxicity levels. In spite of Japonica-type, Sanduljinmi and kumyoung showed 3-4 and 4-5 levels. Target resistant gene, Hydroxyphenylpyruvate dioxygenase inhibitor sensitive gene No.1 (HIS1) have been isolated from five domestic rice cultivars (Sangjubyeo, Sambaekbyeo, Sanduljinmi, Kumyoung and IR8). Results of the sequence through PCR, all five tested rice cultivars had HIS1 gene regardless to rice cultivars. And the difference between rice varieties from sequence of HIS1 were identified some variation in genes.

This study was conducted to investigate on regeneration and sproutind by buried soil depth, and effective control of Paspalum distichum var. indutum dominanting in upland field and levee. P. distichum var. indutum was regenerated regardless of sizes of cutting stem but not regenerated after treatment of effective herbicides to P. distichum var. indutum. The P. distichum var. indutum was not sprout in burying soil depth of the 20cm, and showed low competition ability in the rice field. The P. distichum var. indutum were controlled effectively by treatment of pyrazosulfuron-ethyl/ molinate, cyhalofop-butyl, cyhalofop-butyl/bentazon and fenoxaprop-P-ethyl. These herbicides showed control effect of more than 90% at 20 days after treatment. And also, clomazone and paraquat controlled effectively P. distichum var. indutum in levee

The National Institute Agricultural and Science Technology, the National Crop Experiment Station, the National Honam Agricultural Experiment Station and the National Yeongnam Agricultural Experiment Station did Paddy weed survey from 2000 to 2001. Weeds of paddy rice fields are composed of 76 species belonging to 22 families. Dominance by family is 11.8%, 20.4%, and 12.8% in Poaceae, Cyperaceae and Pontederiaceae, respectively. Dominance by species is 12.7%, 9.5%, 9.5%, and 9.1% in Monochoria vaginalis, Eleocharis kuroguwai, Echinochloa spp., and Sagittaria trifolia, respectively in decreasing order. Annual broadleaf weeds and perennial are widely distributed. Annual weeds showed high dominance of 70% compared with perennials weeds. Dominant weeds occurring in different cultivation methods are Echinochloa spp. in direct seeded paddy fields and Rindernia procumbens and Monochoria vaginalis in double cropping paddy fields after barley cultivation. The current survey indicated that annual weeds such as Monochoria vaginalis and Echinochloa spp. were widely distributed and perennial weeds have greatly increased for the last 10 years