• The Korean Journal of Ecology
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• v.27 no.2
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• pp.107-114
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• 2004

Tomato (Lycopersicon esculentum) seedlings exposed to various concentrations of $CdC1_2$ (0∼100 $\mu$M) in the nutrient solution for up to 9 days were analyzed with the seedling growth, $H_2O_2$ production, glutathione levels and activity changes of enzymes related to $H_2O_2$ removal. The growth of seedlings was inhibited with over 50 $\mu$M Cd, whereas the levels of $H_2O_2$ and glutathione were enhanced with Cd exposure level and time. Meanwhile, Cd exposure increased the activities of catalase (CAT) and glutathione reductase (GR) but decreased the activities of dehydroascorbate acid reductase (DHAR) and ascorbate peroxidase (APX) in both leaves and roots. These results suggest that the altered activities of antioxidant enzymes particularly involved in the $H_2O_2$ removal and the subsequent $H_2O$$_2$ accumulation could induce the Cd-induced phytotoxicity.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.132-137
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• 1997

Phytotoxicity of the culture filtrate and culture conditions for the production of the phytotoxin by Exserohilum monoceras 92-044 were examined. The necrotic lesions were developed on the leaves of Echinochloa crus-galli within 48 hrs after inoculation of the culture filtrate, and the leaves were completely blighted within 5∼7 days. Maximum toxicity was found in the culture broth containing 20% V-8 juice. Phytotoxin accumulation and fungal growth reached their highest peak at around 11 days. Typical symptom appeared on the leaf of E. crus-galli within 48 hrs. Only a weak chlorosis appeared on rice, Arundinella hirta (THUNB) and henry crabgrass (Digitaria sanguinalis SCOP.), but no further symptom developed.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.1-3
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• 1984

• The Plant Pathology Journal
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• v.24 no.4
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• pp.417-422
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• 2008

Apicidin is a cyclic tetrapeptide produced by some Fusarium species and is known to inhibit Apicomplexan histone deacetylase. The goals of this study were to determine species identity of Fusarium isolate KCTC16676, an apicidin producer, to improve a method for apicidin extraction, and to test phytotoxicity of apicidin and its analogs. We compared sequences of the translation elongation factor 1-alpha (TEF) gene in KCTC16676 with those from isolates representing diverse Fusarium species, which showed that KCTC16676 belongs to the F. semitectum-F. equiseti species complex. To enhance apicidin production, after culturing isolate KCTC16676 on a wheat medium for 3 weeks at $25^{\circ}C$, the culture was extracted with chloroform. Apicidins were purified through a reverse phase $C_{18}$ silica gel column, resulting in 5 g of apicidin, 200 mg of apicidin A, and 300 mg of apicidin $D_2$ from 4 kg of wheat cultures; this represents a significant yield improvement from a previous method, offers more materials to study the modes of its action, and facilitates the elucidation of the apicidin biosynthesis pathway. Apicidin and apicidin $D_2$ showed phytotoxicity on both seedlings and 2-week-old plants of diverse species, and weeds were more sensitive to apicidins than vegetables

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1129-1134
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• 2009

Increasing application of nanotechnology highlights the need to clarify nanotoxity and nanoparticles characterization. However, few researches have focused on phytotoxicity of nanoparticles. This study was to examine phytotoxicity on Cumumis sativus seedling and the dissolution of Zn, ZnO nanoparticles in hydroponic culture system. Results of this study; characteristics of Zn, ZnO nanoparticles are more aggregated in nutrient solution than deionized water. C. sativus biomass significantly reduced in the nutrient solution were higher than 100 mg/L, and Zn toxicity showed $Zn^{2+}$> Zn> ZnO NPs. Results of transmission electron microscopy images, Zn and ZnO nanoparticles greatly adhered onto the root cell wall and nanoparticles were observed in the root cell.

• Journal of Soil and Groundwater Environment
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• v.21 no.3
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• pp.82-87
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• 2016

This study investigates effects of an aging period on arsenic (As) chemical forms in soils and phytotoxicity using artificially As-contaminated soils with a range of As concentrations (0-300 mg/kg) and aging periods (0 and 3 months). A sequential extraction procedure showed that the increasing As concentration in soils increased the ratio of non-specifically and specifically bound As, which are known to be bioavailable. This resulted in increasing As uptake by tomatoes with increasing As concentration (R²=0.87 for exponential fitting); however, the seed germination was not sensitive to the As concentrations of the soil samples. The seed germination was also statistically similar in the soils with 75 and 150 mg-As/kg regardless of the aging period. The time taken until the seed germination (i.e., lag phase), on the other hand, decreased from 10 d to 3 d with aging for 3 months. This can be attributed to the decreased amount of bioavailable As with aging. Overall, this study shows that when the toxic effects of the As-contaminated soils are assessed using tomato plants, it is better to use more sensitive methods than seed germination such as the As accumulation or the lag phase for seed germination.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.21-24
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• 1986

This experiment was conducted to find out the feasibility of foliar application of mixed solution of urea and agricultural chemicals. One to two percent urea solution and chemicals were combined for joint application and the degradation of mixed solution was tested and its phytotoxicity was evaluated on rice plant. There were no changes of pH and components of mixed solution of urea and chemicals. However, it led to phytotoxicity in rice plant and more severe in higher urea content. The yields of rice were slightly lower in the mixed solution plot than in check one, however, no significant statistical difference was observed. Due to phytotoxicity, the foliar application of mixed solution is not agronomically sound.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.106-110
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• 1991

There was a tendency that the growth inhibition of early growth due to herbicides was increased with increasing the amount of fertilizers. As a matter of fact, pretilachlor and pyrazolate increased the degree of injury with increasing the amount of fertilizers, and dimepiperate was actually safe regardless of the amount of fertilizer applied, while in case of bensulfuron, the injury become less when it was applied without fertilizers. As for organic matters, dimepiperate and pyrazolate were rather safe without organic matter, while pretilachlor and bensulfuron become really safe with the application of organic matter more than 1,000 kg/10a.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.100-105
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• 1991

Maintaining the water level at 5cm depth showed less decreasing in number of tiller and dry weight as compared to 1 and 3cm depths when Bensulfuron and Pretilachlor were applied. The drainage more than 5cm as water level everyday caused the growth inhibition when Bensulfuron and Pretilachlor were used, while Dimepiperate was rather safe.

• Korean Journal of Environmental Agriculture
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• v.6 no.1
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• pp.44-49
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• 1987

Present work has been initiated to see if inherent biochemical difference among plants is, in any way, related to the observed selectivity characteristics of preemergence herbicide, alachlor. Application of aqueous solution of alachlor onto three intact plants, soybean, chinese cabbage and barnyard grass resulted in phytotoxicity responses in the testt plants in varying degree. Examination of glutathione (and homoglutathione) contents of the test plants indicated that the phytotoxicity is inversely proportional to the peptide contents of the test plants. It was also noted that four to five water soluble metabolites are readily formed in intact seedling treated with labelled alachlor and glutathionealachlor and homoglutathionealachlor conjugates were tentatatively identified as major metabolites. It is concluded that conjugation reaction involving glutathiones and xenobiotic alachlor, a typical phase II reaction, acts as detoxification reaction in the three test plants and this would, in turn, contribute to observed selectivity of alachlor.