• 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.9 no.1
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• pp.108-111
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• 2005

A series of N-[4-cyano-2-fluoro-5-(2-pyrimidinyloxy, 2-benzyloxy or 2-pyridinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimides was synthesized, and the herbicidal activities of those deivatives were evaluated through pre- and post-emergence application under upland conditions in a greenhouse. The results showed that most compounds resulted in stronger herbicidal activity on broadleaf weeds than on grass weeds and higher through post-emergence than pre-emergence application. The N-[(4-cyano-2-fluoro-5-(2-pyrimidinyloxy) phenyl]-3,4,5,6-tetrahydrophthalimide showed the best weed control efficacy and marginal corn safety at a rate of 60 g/ha through pre-emergence application.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.262-265
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• 2006

A series of N-[4-chloro-2-fluoro-5-(2-(substituted)pyrimidinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimides was synthesized, and the herbicidal activities of those derivatives were evaluated through pre- and post-emergence application under upland conditions in a greenhouse. The results showed that most compounds resulted in stronger herbicidal activities on broadleaf weeds than on grass weeds. The N-[4-chloro-2-fluoro-5-(2-pyrimidinyloxy)phenyl]-3,4,5,6-tetrahydrophthalimide showed the best weed control efficacy and marginal corn safety at a rate of 60 g/ha through pre-emergence application.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.191-198
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• 2010

The objective of this study was to find herbicidal compounds from seven different plant essential oils such as amyris (Amyris balsamifera), cajuput (Melaleuca cajeputi), geranium (Pelargonium graveolens), lavender (Lavendula spp.), mandarin (Citrus reticulata), pine (Pinus spp.) and rosemary (Rosmarius officinale), and determine their herbicidal activities. The in vitro herbicidal activity of cajuput essential oil was the highest among six essential oils ($GR_{50}$ value, $425{\mu}g\;g^{-1}$) and major chemical components in cajuput essential oil were eucalyptol (37.2%), ${\alpha}$-terpineol (11.6%), benzaldehyde (5.2%), linalool (4.1%), ${\alpha}$-pinene (2.5%) and ${\beta}$-pinene (2.4%), and their $GR_{50}$ values were 2,731, 500, 50, 372, 4,363, and $4,671{\mu}g\;g^{-1}$, respectively. Soil application of cajuput essential oil and benzaldehyde did not show any herbicidal activity at 80 kg $ha^{-1}$. When cajuput essential oil was applied to foliar at 80 kg $ha^{-1}$, narrow-leaved plants such as sorghum (Sorghum bicolar), barnyardgrass (Echinochloa crus-galli), and southern crabgrass (Digitaria ciliaris) were killed 100%, however, broad-leaved plants indian jointvetch (Aeschynomeme indica), velvet leaf (Abutilon theophrasti), cocklebur (Xanthium strumarium), Japanese morningglory (Calystegia japonica) were not killed, indicating the cajuput essential oil was effective to control narrow-leaved plants. Herbicidal activities of benzaldehyde at 80 kg $ha^{-1}$, to those plants were 20, 60 and 95%, respectively. Overall data showed that the herbicidal activity of cajuput essential oil was in part due to benzaldehyde.

• The Korean Journal of Pesticide Science
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• v.5 no.3
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• pp.54-57
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• 2001

A series of bicyclic 4,5,6,7-tetrahydroindazole derivatives 6 have been synthesized, and their herbicidal activities were studied in flooded paddy condition. The compounds 6 showed herbicidal effects to barnyardgrass and Monochoria and good tolerance against rice at a rate of $0.063kg/ha{\sim}0.25kg/ha$.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.320-323
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• 2002

New and fast degradable sulfonylurea derivaties possessing N-methylureido group were synthesized and their herbicidal effects were tested under the upland in greenhouse. N-methylureido benzenesulfonylureas showed better herbicidal activity against grass weeds than broad leaf weeds under post emergence.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.72-75
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• 2000

3,4-Dimethyl-N-[4-chloro-2-fluoro-5-{(pyrazolylmethyl)oxy}phenyl]maleimides or 3,4,5,6-tetrahydro-N-[4-chloro-2-fluoro-5-{(pylazolylmethyl)oxy} phenyl]phthalimides were prepared and evaluated their herbicidal activities under paddy conditions. Those compounds which have N-methyl-5-pyrazolylmethyloxy moiety showed good tolerance in transplanted rice and strong herbicidal activities on barnyardgrass below 60 g/ha of dose.

• Korean Journal of Plant Resources
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• v.9 no.1
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• pp.47-54
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• 1996

To search herbicidal compounds in Pulsatilla koreana Nakai, methanol extract of P. koreana roots was purified by sequences of XAD-7 column chromatography, silica gel adsorption column chromatography, silica gel flash column chromatography, preparative layer chromatography and preparative high performance liquid chromatography(Prep, HPLC).The final Prep. HPLC gave two herbicidally-active fractions. These fractions treatment at 100ppm inhibited the root length of Echinochloa crus-galli seedlings by 48% and 60% as compared with the control, respectively. Components in the two active fractions were analyzed by GC-MS Spectrometry. These compounds, which were isolated from P. koreana roots, were identified as several fatty esters, hydrocarbons, squalene, evidonol, and a diazepin analogue.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.356-361
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• 2006

The present study was conducted to determine plant growth and physiological responses of corn, barnyardgrass, and soybean to ALA (5-aminolevulinic acid). ALA effect on early seedling growth of test plants was greatly concentration dependant, suggesting that it inhibits at higher concentrations. No significant difference in herbicidal activity of two types of ALA on plant height and weight of test plants was observed. Barnyardgrass was the most sensitive to ALA and followed by corn and soybean, indicating that both crop plants were less affected by ALA concentration as well as different growth stages than barnyardgrass. Greatly reduced chlorophyll contents from leaves of three plant species were observed with increasing of ALA concentration. Compared with untreated controls, higher amounts of three tetrapyrroles were detected from three crop plants, indicating more accumulation in ALA-treated plants. The differential selectivity among plant species would be explained with the differences in tetrapyrrole accumulating capabilities, the susceptibility of various greening groups of plant species to the accumulation of various tetrapyrroles, and their metabolism in various plant tissues. The results indicate that negative biological potential of ALA exhibited differently on plant species, and that the photodynamic herbicidal activity against susceptible plants highly correlated with the extent of tetrapyrrole accumulation by the species.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.67-71
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• 2007

Nobel series of 5-benzyloxymethyl-3-(thiophen-5-yl)-1,2-isoxazoline derivatives were designed and synthesized. The herbicidal activities of these compounds to main dominant weeds to these compounds were evaluated in pot tests that simulated rice paddy conditions. Most of the compounds showed high herbicidal activity to main dominant weeds occurring in rice field without the serious rice injury.