• KSBB Journal
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• v.9 no.5
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• pp.469-474
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• 1994

The purpose of the work was to evaluate the feasibility of a biological treatment process for the phenoxy alkanoic herbicide 2,4-D(2,4-dichlorophenoxyacetic acid) as a commercial pesticide. The phenoxy herbicide was 2,4-D amine salts which contained 40%(vol/vol) 2,4-D and 60%(vol/vol) solvent. A microbial consortium has been derived by enrichment with 2,4-D. The consortium utilized 2,4-D as the sole source of carbon and energy. Optimal pH on the 2,4-D degradation was 7.0 in this experiment. As concentrations of 2,4-D were increased, the degradation by microbial consontium became inhibited. The amendment with yeast extract and ascorbic acid accelerated the degradation of 2,4-D. High performance liquid chromatography methodology was used to measure 2,4-D and it also resolved 2,4-DCP(2,4-dichlorophenol), the corresponding phenol as intermediate. Gas chromatography-mass spectrometry was used for preliminary identification of the intermediate 2,4-DCP. UV scans of spent cultures showed that the maximum absorption of 2,4-D at the wavelength of 283 nm was decreased toward the end of incubation, but the consortium displayed no detectable spectral changes or peak shifts in the UV absorbance.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.36-45
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• 2001

This study was conducted to search new target enzymes of novel herbicide candidate. Total of 107 biochemical inhibitors reported to inhibit over than 100 different plant enzymes were purchased from commercial chemical companies. 15 inhibitors and 34 enzymes were selected by germination assay, seedling assay, wheat leaf disc assay, and whole plant assay. Among them, seven compounds of purine, phehyl-hydrazine, o-phenanthroline, oleylamine, dicyclohexylcarbodiimide, 7,8-benzoquinoline, and aminooxyacetic acid showed high herbicidal activity in the whole plant assay under greenhouse while 7,8-benzoquinone, 8-hydroxyquinoline, 2,2'-dipyridyl, and o-phenanthroline inhibited seed germination of barnyardgrass, rice, and tomato at concentrations of 1.25 to $5{\mu}M$. The compounds of 7,8-benzoquinoline, chlorpromazine, cyanuric fluoride, 4-methylpyrazole, oleylamine, tranylcypromine, and trifluoperazine inhibited the growth of cyanobacteria at 30 to $100{\mu}M$. The compounds of dicyclohexylcarbodiimide and chlorpromazine exhibited whitening effect on tile wheat leaf disc at $100{\mu}M$. These results suggest that the plant-specific enzyme inhibitors which have biological activities may supply the target enzyme for developing new herbicide candidate.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.715-718
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• 2001

5-Aminolevulinic acid (ALA) can be used as a photodynamic herbicide / insecticide and also applied to photodynamic therapy for malignant skin tumor. In this study we developed recombinant E. coli system for the high productivity of ALA and for the on-line monitoring of fusion protein (EGFP::ALAS) by a fluorescence sensor.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.401-404
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• 2011

Bromobutide, a paddy field herbicide, can effectively control annual and perennial weeds. It has an excellent weeding effect especially against Monochoria vaginalis and Scirpus juncoides etc. When it is mixed with other herbicides controlling weed spectrum and application timing can be broaden. Bromobutide has stable weeding effects regardless of field and weather conditions, and there is almost no phyototoxic effects to rice.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.65-70
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• 1997

Among 980 fungal strains isolated from the lesions of Trifolium repens L. and various weeds, three Penicillium sp. F40362, F40496, F40497 were selected by the first selection test and a pathogenicity test. The spores of these strains germinated readily 90 to 100% and readily infected the respective plant. The wheat bran-corn starch formulation of F40362 strain showed 100% mycoherbicidal activity against clover plant at $4{\times}10^8$ spores/pot. The same formulations of F40496 and F40497 strains showed 100% mycoherbicidal activity against clover plant at $12{\times}10^8{\sim}4{\times}10^8$ spores/pot. The same formulations of tee strains showed over 30% mycoherbicidal activity against Leguminosae plants. This method of pelletiation was potentially useful for the production of inoculum formulation as mycoherbicides and it was effective enough to treat $2{\sim}2.5\;g$ formulation($4.5{\times}10^7\;spores/mg$) to a $350\;cm^2$ pot. The three strains, F40362, F40496 and F40497 have selective mycoherbicidal activity between Trifolium repens L. and Zoysia japonica and nonselective mycoherbicidal activities against some other crop plants and weeds.

• Weed & Turfgrass Science
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• v.2 no.1
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• pp.23-29
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• 2013

This study was conducted to clarify effects of weed control methods on damages from agricultural chemicals of pear trees, growth of weeds and states of pear trees after treating pear orchards with different methods of weed controlling, density of GLU and application times. The growth and occupation rate were investigated after 10, 20 and 40 days of weeding treatment. According to a result of the first treatment conducted when weeds in the lower parts of crown in a pear orchard began to grow and grew about 20 cm, unwoven cloth covering showed the highest control value with 100% in all 14 kinds of grasses. In comparison, Stellaria aquatica and catchweed bedstraw showed 96.7% and 97.3% respectively in the 20 DAT investigate after the first treatment of GLU 540 g a.i. ha-1 and the high control value of 100% in other all kinds of grasses. According to an investigation of stalk enlargement, length of new shoot and the number of new shoot made to know differences in tree growth following treatment of the lower part of crown, to use weed killers two or three times a year or to eliminate grasses with machines have positive effects on cross growth of pear trees.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.440-446
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• 1995

In order to select the proper formulation of newly developed herbicide Cyhalofop-butyl{n-butyl-(R)-2-[4-(2-fluro-4-cyanophenoxy)phenoxy]propionte} to Echino-chloacrus-galli(L)P. Beaw. several formulations were made and tested by biological assay. Weed control of wettable powder formulated with two adjuvants on E. crus-galli showed higher effect as compared with the formulation made without adjuvants. Higher concentration of adjuvants resulted in higher absorption and higher weed control on E. crus-galli. However, adhesional force of wettable powder applied to leaf surface was not positively correlated to the amount of herbicide absorption. The weeding effect and amount of herbicide absorbed on E. crus-galli were higher by emulsifiable concentrateformulations with different HLB and non ionic surfactants as compared with wettable powder formulations. The higher adhesional force and higher absorption of herbicide on E. crus-galli were obtained from microemulsion than the others. Granulization of the herbicide with appropriate adjuvants in a form of resurfacing on the submerged water gave rise to a good weeding effect and believed to be a possible promising formulation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.3
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• pp.47-54
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• 1978

Weed control is an essential part in rice culture and has been practiced by hand. But the shortage of man power in rural area in recent years has brought about the use of herbicides. The effective use of herbicides in rice has contributed toward improving labor situation and maintaining rice production. The use of herbicides will extend more in the future. The only limitation of present uses of monoherbicides might be the predominant growth of a certain weeds in paddy field, and subsequent effect on ecology system. It is, therefore, wanted to develop a herbicide which will be effective on several kinds of weeds. In the weed control system, ecological and integrated weed control would be necessary in the future. To obtain the most effective weed control, studies on physiological ecotype of weeds and machanism of herbicides and their interactions will be necessary.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.65-70
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• 1999

This study was conducted to develop a simple selection method for herbicide-resistance weeds. Two methods, designated "seedling method" and "stem node method" were employed for screening of barnyardgrass against propanil and butachlor. In the seedling method, shoot and root growth of barnyardgrass were significantly inhibited at quarter of the recommended herbicide rate, while in the stem node method, the similar inhibition was obtained at half of the recommended rate. Thus, it was concluded that the seedling method is more simple and quick method to evaluate response of barnyardgrass to propanil and butachlor compared to stem node method.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.471-474
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• 2001

To optimize the culture conditions for fungal pathogen YK101, the effects of culture medium, temperature and agitation on mycelium production were investigated. The optimum temperature and agitation for the cultivation of YK101 were $28^{\circ}C$ and 150rpm, respectively. The optimized medium was composed of 1.0- 2.0% total sugar from sucrose, 1.0% yeast extract and 0.05% $MgSO_4$ ${\cdot}$ $7H_2O$.