• Korean Journal of Weed Science
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• v.12 no.2
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• pp.102-109
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• 1992

There was significant reduction in the mitotic indices of oat roots treated with alachlor. Uniform decrease in prophase, metaphase, anaphase, and telophase as treatment time increasing was observed. Alachlor did not disrupt mitosis, but rather inhibited the onset of mitosis. Labeled dividing cells were significantly inhibited, but the number of labeled interphase cells of all treatment were increased, as compared with control in 8 hr and 12hr period. Labeled dividing cells which entered mitosis thru $G_2$ were inhibited approximately 68% at 8hr after treatment with $1{\times}10^{-5}$ M of alachlor. Alachlor apparently inhibited from the $G_2$stage into mitosis of dividing cells. After 24 hr treatment, 12.1% abd 46.6% inhibition of coleoptile growth occurred at $1{\times}10^{-5}$ M and $1{\times}10^{-4}$ M, respectively. Cell elongation was inhibited by alachlor but was less sensitive than cell division. The longitudinal section cells of oat roots treated with $1{\times}10^{-4}$ M alachlor for 12 hr were observed to be enlarged central cylinder and also showed degradation of apical meristem zone, as compared with the untreated roots.

• Korean Journal of Weed Science
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• v.17 no.2
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• pp.214-219
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• 1997

The influence of manure, chemical fertilizers, heavy metals and cleaner on the rate of degradation of alachlor in soil was studied. The degradation rate of alachlor in the soil followed first-order reaction kinetics. The half-life was 6.4 days. The degradation was accelerated by the amendment of manure. Adding chemical fertilizers to the soil enhanced alachlor degradation more in the presence of nitrogen than potassium. On the other hand, adding heavy metals or cleaner to the soil decreased the degradation rate. The half-life of alachlor in soil treated with Cd, Cr, Ni, Zn and Cu was 11.0, 8.3, 7.9, 7.2 and 6.7 days, respectively, and that of the cleaner is 7.5 days. The microbial biomass and the respiration rate in the soil were promoted by the amendment of manure and chemical fertilizers, and inhibited by the addition of heavy metals and cleaner. The degradation rate correlate positively with the microbial biomass and the respiration rate.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.368-373
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• 1992

The effect of alachlor treatment on protein synthesis was studied. Protein synthesis was inhibited by $1{\times}10^{-4}$ M and $1{\times}10^{-3}$M of alachlor 5.8% and 86.5%, respectively, while did not occur blow $1{\times}10^{-5}$M alachlor. Soluble protein of alachlor treated oat root tips was examined by polyacrylamide gel electrophoresis. The proteins extracted from oat root tips showed that they were made up of subunits blow 100 kd polypeptides by SDS-PAGE. As compared to control, high molecular proteins(above 47 kd) were inhibited of oat root treated with alachlor, while low molecular proteins(below 23 kd) were increased. Two-D gels showed that alachlor caused decrease(1-6 spots) or increase(7-10 spots) in number of polypeptides on silver staining. The intensity of some polypeptides of soluble proteins (molecular mass of 83 kd : 1, 2 spots, 70 kd : 3, 4 spots, and 47.5 kd : 5, 6 spots) decreased in alachlor treatment, whereas the intensity of other peptide bands (20 kd : 7 spot and 16 kd : 8, 9, 10 spots) increased. Oat root tip proteins present in the neutral zone are masked by diffusing of major proteins, but proteins in acid zone are resolved minor proteins.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.64-72
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• 1984

Alachlor, 2-chloro-2, '6'-diethyl-N-(methoxymethyl) acetanilide, which had been incubated in the flooded paddy soils yielded 1-formyl-2,3-dihydro-7-ethylindole, 2,6-diethylaniline, 2,6-diethylacetanilide, 2,6-diethyl-N-(methoxymethyl) acetanilide, 2-hydroxy-2, '6'-diethyl-N-(methoxymethyl) acetanilide, and three unidentifiable compounds as its degradation products. The water-soluble products of Alachlor in soil suspensions increased with incubation periods and similar results were obtained from the incubation of Rhizoctonia solani, as verified by use of the ring $-^{14}C-$labeled Alachlor. Streptomyces lavendulae Ru 3340-8 produced 2-hydroxy-2, '6'-diethyl-N-(methoxymethyl) acetanilide as the major degradation product as much as 25%, whereas Bacillus brevis IFO 3331, Bacillus cruciviae, and Pseudomonas putida did not produce it.

• Applied Biological Chemistry
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• v.20 no.3
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• pp.310-316
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• 1977

The adsorption of 2-Chloro-4-(ethylamino)-6-(isopropylamino)-s-trazine (Atrazine) and 2-Chloro-2' 6' diethyl-N(methoxymethyl)acetanilide(Alachlor) by 21 Korean surface soils is studied and discussed in relation to some properties of soils. 1. Adsorption of Atrazine was correlated posisively with content of clay and organic matter, but negatively with extractable potassium content and sand content. 2. Adsorption of Alachlor was correlated positively with organic matter, caly content and CEC, but negatively with sand content 3. Isothermal adsorpsion of Alachlor was confirmed to the Freundlich eguation.

• Advances in environmental research
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• v.2 no.4
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• pp.261-277
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• 2013

The degradation of alachlor has been investigated using sonolysis (US), photocatalysis (UV) and sonophotocatalysis (US/UV) using three photocatalyst viz. $TiO_2$ (mixture of anatase and rutile), $TiO_2$ (anatase) and ZnO. The effect of photocatalyst loading on the extent of degradation of alachlor has been investigated by varying $TiO_2$ (both types) loading over the range of 0.01 g/L to 0.1 g/L and ZnO loading over the range of 0.05 g/L to 0.3 g/L. The optimum loading of the catalyst was found to be dependent on the type of operation i.e., photocatalysis alone or the combined operation of sonolysis and photocatalysis. All the combined processes gave complete degradation of alachlor with maximum rate of degradation being obtained in the case of sonophotocatalytic process also showing synergistic effect at optimized loading of photocatalyst. About 50% to 60% reduction in TOC has been obtained using the combined process of sonophotocatalysis depending on the operating conditions. The alachlor degradation fitted first order kinetics for all the processes under investigation. It has been observed that the $TiO_2$ (mixtrure of anatase and rutile) is the most active photocatalyst among the three photocatalysts studied in the current work. The effect of addition of radical enhancers and scavengers on sonophotocatalytic degradation of alachlor has been investigated in order to decipher the controlling mechanism. The alachlor degradation products have been identified using LC-MS method.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.72-75
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• 2018

Balloon flower (Platycodon grandiflorum) is one of minor crops in Korea. Only four ACCase inhibiting herbicides are registered for P. grandiflorum and the farmers usually use general but unregistered herbicides which can cause critical phytotoxicity. So, this study was conducted to investigate effects of alachlor and pendimethalin on germination and early growth of P. grandiflorum. To evaluate the effect of alachlor and pendimethalin, two herbicides were treated to the seeds in petri-dish and soil. In the petri-dish, alachlor completely inhibited the germination as well as pendimethalin inhibited the germination slightly but not significantly. In case of soil application, alachlor inhibited germination and plant height of P. grandiflorum significantly as well as pendimethalin inhibited plant height and root length significantly. We showed the possibility of phytotoxicity of alachlor and pendimethalin to P. grandiflorum and strongly suggest that two herbicides should not be used to the cultivation of P. grandiflorum. Unregistered herbicides should not be used for weed management and additional researches for screening of safe herbicide to minor crops should be conducted as soon as possible.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.135-143
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• 1995

This study was conducted to investigate the adsorption characteristics, distribution coefficients, and movement of alachlor(2-chloro-2', 6'-dimethyl-N-(methoxymethyl) acetanilide) and chlorothalonil(tetrachloroisophthalonitrile) for the 3 soils sampled from major soil groups in Cheju Island. Namwon, Jeju, and Mureng soils used in this study were classified as black volcanic ash soil, dark brown volcanic ash soil and dark brown nonvolcanic soil, respectively. Organic carbon content and CEC of Namwon soil were very high and those of Mureung soil were very low. Linear and Freundlich adsorption isotherms were the best to fit the adsorption of alachlor and chlorothalonil in the soils. K value, Freundlich coefficient, of alachlor for Namwon soil was 21.38, being 5.4 and 97.2 times higher than that for Jeju and Mureung soils respectively. The values of chlorothalonil for the soils were similar to those of alachlor but were much higher than them. When Mureung, Jeju and Namwon soil columns were leached with a solution containing 10.25 mg/l of alachlor and 1.50 mg/l of chlorothalonil, alachlor was first detected at 0.265, 0.47, and 1.86 pore volume (PV) and chlorothalonil was 3.71, 4.7 and 17.5 PV, respectively. The pore volumes at $C/C_o=1$ of alachlor in the leachates from Mureung, Jeju and Namwon soil columns were 1.1, 3.7 and 6.6 PV and those at $C/C_o=0.2$ of chlorothalonil were 7.5, 8.5 and 27.5, respectively. This means that the deceasing order of the mobility of the chemicals in soils was Mureung soil>Jeju soil${\gg}$Namwon soil. The pore volumes detecting $C/C_o=0.5$ of alachlor and $C/C_o=0.05$ of chlorothalonil in leachate were positively correlated with the distribution coefficients for the soils.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.62-69
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• 1983

This experiment was carried out to find the effect of seeding rates and herbicides on the weed control, yield and crude protein of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench). The variety used in the present study was Pioneer 988. Two different seeding rates were 25 kg/ha and 50 kg/ha and five weed control treatments were weedy check, hand weeded check, alachlor, alachlor+simazine, and simazine of preemergence application. The results of this study are summarized as follows: 1. Forage yield was not influenced by seeding rates. There was no significant difference between forage yield from 25 kg/ha and from 50 kg/ha of seeding rates. But weedy plots showed higher yield from the high seeding rate. Alachlor+simazine treatment showed the greatest yield among the weed control treatments. But there was no difference among the hand weeded treatment, simazine treatment, and alachlor+simazine treatment. 2. Seeding rates did not affect weed yield, but weedy plots showed the tendancy toward higher weed yield from the low seeding rate. Alachlor+simazing preemergence application showed the most effective weed control. But there was no significant difference in weed yield among the treatments of the hand weeded, alachlor+simazine and simazine. The weed yield in alachlor treatment was significantly higher than other three treatments. 3. The height of plant was shortest on the weedy plots and the longest height was obtained from the alachlor+simazine application. But in the first harvest the height was reduced by herbicides. Seeding rates did not affect the plant height. But the height was slightly taller under the low seeding rate than under the high seeding rate. 4. The percent crude protein of the forage did not affected by two seeding rates. Simazine treatments increased the percent crude protein and total crude protein yield. Simazine and alachlor+simazine application showed the significantly higher percent crude protein than hand weeded and alachlor treatments. Simazine increased the percent crude protein without reduction of forage yield. 5. Whereas the number of original stand was greater in the high seeding rate, the number of tillers per stand was higher in the low seeding rate. Weed reduced the number of stands and tillers. There was no significant indifference among the weed control treatments. It is concluded from above results that when sorghum-sudangrass hybrids are broadcasted for forage, 25 kg/ha rate of seeding is appropriate and alachlor+simazine treatment is most effective on weed control, maximum forage yield, and high percent crude protein.

• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.187-193
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• 2012

Acute toxicity, water resolvability and short term reproduction test on Japanese medaka (Oriyzias latipes) for evaluating alachlor susceptibility to endocrine system were studied. Alachlor is known for suspected endocrine distruptors. As the results of tests, $LC_{50}$ (Median lethal concentration) was determined as 2.36 (1.994~2.805) mg/L, and test water replaced at 7 day intervals as its water resolvability was less than 20% in 7 days. The short term reproduction tests on Japanese medaka (Oriyzias latipes) were performed with a solvent control group, a treated group (alachlor concentrations of 0.02, 0.04, 0.11, 0.27, 0.68 ppm) and a positive control group (17 ${\beta}$ estradiol, 0.01, 0.1, 0.5 ppb). The number of spawning and embryo rates were declined in a alachlor-dose dependent manner, and the number of unfertilized eggs rates were in contrast increased depending on the concentrations. Further study should be needed to confirm whether the adverse effects may be effected by the concentrations. Additionally, alachlor was evaluated as a non-vitellogenin by the result of a test of significance of the vitellogenin content test for determination of the effect of estrogen among the endocrine disruptors.