• Korean Journal of Weed Science
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• v.2 no.1
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• pp.53-56
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• 1982

In order to establish the chemical weed control systems in orchard, efficacy of glyphosate and paraquat with oxyfluorfen, simazine and alachlor were evaluated in pear and peach orchards. Dominant weed species existed before glyphosate or paraquat application were Artemesia princeps, Calystegia japonica, Erigeron canadensis, and Lepidium apetalum, but Digitaria sanguinalis was one of the most dominant weeds throughout growing season of fruit trees. Gtyphosate at 120g/10a followed by oxyfluorfen at 04g/10a drastically reduced number of weeds and fresh weight of weeds and was found to be the most effective method for controlling weeds in orchard. Paraquat at 100g/10a followed by oxyfluorfen at 117g/10a and sequential application of glyphosate at 120g/10a also provided good weed control.

• Korean Journal of Weed Science
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• v.31 no.2
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• pp.192-198
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• 2011

This study was conducted to investigate the herbicidal activity against Scirpus planiculmis (SCPPL) which has been reported as resistant biotype on sulfonylurea (SU) herbicides at the west coast reclaimed area first and proliferated continuously at Hwasung and Pyeongtaek in Gyeonggi province, and some Chungnam province. In order to investigate resistance breakability against SCPPL, new rice herbicides containing tefuryltrione [p-hydrophenyl pyruvate dioxygenase (HPPD) inhibitor], pyrimisulfan and triafamone[actolactate synthethase (ALS) inhibitor] were tested. In both lab and field experiments, tefuryltrione GR, 4-HPPD inhibitor showed growth retardation with a bleaching on the young leaves of SCPPL at early time after treatment. However, it restored and regerminated with insufficient control effect. On the other hand, pyrimisulfan+mefenacet SC, triafamone+tefuryltrione GR, and ALS inhibitor showed excellent control effect on SU-resistant SCPPL with growth retardation and necrosis. In particular, pyrimisulfan+mefenacet SC showed excellent controlling effect on SU-resistant SCPPL in regional field experiments.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.68-71
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• 2001

Of the cyclic imide type compounds, S-275 was known to exhibit a potent herbicidal effects. We have designed and synthesized the compounds having diverse subsutuents in place of the chlorine group of bicyclic 4,5,6,7-tetrahydroindazole part of S-275. Their herbicidal activities were studied under flooded paddy conditions. The results showed that the most compounds gave relatively weak herbicidal activities, whereas tile compound substituted with methylthio group showed potent herbicidal effects against paddy weeds at a rate of 0.015 kg/ha and improved tolerance on rice compared to S-275.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.181-184
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• 2005

The heterocyclic PPO inhibitor compounds have been studied due to their potent herbicidal effects without toxic to human and animals. We have designed and synthesized 4,5,6,7-tetrahydroindazole, maleimide, and tetrahydrophthalimide compounds carrying diverse epoxide substituents at 5- position of the phenyl group. Their herbicidal activities were evaluated under submerged paddy conditions. These results showed that 4,5,6,7-tetrahydroindazole compounds gave potent herbicidal activities especially to ECHOR, MOOVA, and CYPSE at a relatively low rate of 16 g/ha and improved tolerance on rice compared to S-275 as a standard herbicide in this experiment.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.133-138
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• 2012

This study was conducted to investigate the herbicidal activity against resistant biotype on sulfonylurea (SU) herbicides such as Scirpus juncoides and Monochoria vaginalis at the glasshouse and paddy rice cultivation area. In order to investigate resistance breakability against SU-resistanted annual weeds, new rice herbicides containing tefuryltrione [p-hydrophenyl pyruvate dioxygenase (HPPD) inhibitor] were tested. In both lab test and field experiment, tefuryltrione mixture, 4-HPPD inhibitor had shown excellent efficacy with a bleaching on the leaves of resistant annual weeds at early time after treatment and showed excellent persistance. Especially, tefuryltrione mixture had shown excellent controlling effect on annual and perennial SU-resistant S. juncoides in the regional field experiment. In phytotoxicity test, this tefuryltrione mixture had shown good selectivity to common rice species.

• The Korean Journal of Pesticide Science
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• v.11 no.1
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• pp.38-45
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• 2007

Laboratory and greenhouse experiments were conducted to determine the herbicidal effect of two types of ${\delta}$-aminolevulinic acid (ALA), microbiologically-produced ALA (Bio-ALA) and synthetically produced ALA (Synthetic-ALA), on plant growth and chlorophyll content of Chinese cabbage. ALA effect on early plant growth was greatly concentration dependant, showing significant inhibition at higher concentrations. Both pre- and post-emergence application of ALA exhibited significant degree of photodynamic phytotoxicity. Older plants with many leaves were more tolerant to ALA than younger plants, showing less injury. No significant difference in herbicidal activity of two types of ALA, Bio-ALA and Synthetic-ALA, on plant height and chlorophyll content of Chinese cabbage was observed. However, residual biological activity and physico-chemical properties of Synthetic-ALA were more stable than those of Bio-ALA. Our results suggest that ALA had herbicidal potential with both pre- and post-emergence application, and that the chemical may be a valuable mean of eco-friendly weed control based on natural microbial substance.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.225-232
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• 2010

The effect of Protox expression site on herbicidal resistance was investigated in wild-type and transgenic rice plants imposed by peroxidizing herbicide oxyfluorfen. The transgenic rice systems involved the plastidal expression of Arabidopsis protoporphyrinogen oxidase (Protox; AP line) and the dual expression of Myxococcus xanthus Protox in chloroplasts and mitochondria (TTS line). The oxyfluorfen-treated TTS4 line showed the lower levels of cellular leakage and malonyldialdehyde and the sustained capacity of 5-aminolevulinic acid synthesis, compared to the oxyfluorfen-treated AP and wild-type lines. During oxyfluorfen action, the TTS4 line had greater herbicide resistance than the AP1 line, indicating that the dual expression of M. xanthus Protox in chloroplasts and mitochondria prevented the accumulation of photodynamic protoporphyrin IX more effectively than the expression of Arabidopsis Protox only in chloroplasts. These results suggest that the ectopic expression of Protox in mitochondria greatly contributes to the herbicidal resistance in rice plants.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.153-158
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• 1996

During the screening of herbicidal substances from microbial secondary metabolites using photoautotrophic cells, a strain of ME-13 with strong herbicidal activity was isolated from soil. Based on the taxonomic studies, the strain was identified as Streptomyces. Two active compounds were purified from the culture broth through the column chromatographies using active charcoal, silica gel, MCI gel, and ODS HPLC. The compounds were identified as AB3217-A and B, respectively, related to anisomycin by spectroscopic methods. AB3217-A and B completely suppressed the germination of radish and barnyard grass at 25 ppm. In comparison to anisomycin, they showed the 6 times higher inhibitory activities against the growth of shoot and root of radish and barnyard grass with EC5O of around 6 ppm.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.201-205
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• 2008

As an ongoing research program for the development of environmental friendly new soil-surface treatment herbicide, several tetrahydroindazole derivatives 6a - 6h possessing hydroxyalkyl subgroup were synthesized and shown to have interesting herbicidal activities exhibiting sumptoms as protoporphyrinogen IX oxidase inhibitor under pre-emergence upland greenhouse screening. Among derivatives tested, compound 6f showed superior herbicidal activity against problem weeds.

• Korean Journal of Plant Resources
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• v.17 no.1
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• pp.28-33
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• 2004

This study was conducted to simple transformants selection by herbicide Basta treatment after transformation with Agrobacteium tumefaciens MP90/PAT in hybrid poplar(Populus alba ${\times}$ P. glandulosa No. 3). In preliminary study, we determined that the lethal concentration of herbicide Basta was 1.0mg/L in callus culture, adventitious bud formation and axillary bud elongation experiment. By the treatment of 1.0mg/L Basta, we could be selected the transformed shoots effectively from the various cultures. In addition, the treatment was useful on selection of transformants which are growing in soil pot. Finally, we also confirmed the transformation by PAT assay, Above results show that the herbicide Basta treatment and PAT assay can be a very simple and effective method for the identification of PAT gene transformed hybrid poplar.