• Applied Biological Chemistry
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• v.48 no.3
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• pp.212-216
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• 2005

Thapsigargin is a specific antagonist of SR/ER-type $Ca^{2+}-ATPase$ in animal tissue, and it was used to characterize the microsomal ATPases prepared from the roots of tomato. When $10\;{\mu}M$ thapsigargin was added, it inhibited the microsomal ATPase activity by 30%. The thapsigargin-induced inhibition was dose-dependent. Since the activity of $Ca^{2+}-ATPase$ is very low in the roots of tomato tissue, it is possible that thapsigargin inhibits the activities of major $H^+-ATPases$ located in plasma and vacuolar membranes. The inhibitory effect of thapsigargin was reduced when the vacuolar $H^+-ATPase$ activity was inhibited by ${NO_3}^-$. However, the effect of thapsigargin was not observed on the $H^+-ATPase$ activity located in the plasma membrane. These results suggest that thapsigargin inhibits the vacuolar $H^+-ATPase$ activity in the roots of tomato.

• Journal of Bio-Environment Control
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• v.16 no.2
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• pp.121-129
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• 2007

Responses of antioxidant enzymes on chilling and drought stress in tomato seedlings were investigated. Growing patterns of tomato based on fresh weight of tomato seedlings were severely affected by chilling and drought stress. Fresh weight of tomato seedlings were reduced by 69.5% in chilling stress and 50.6% in drought stress compared to those in the unstressed control seedlings after 12 days of stress. The specific and gel activity of SOD and POD in the leaves, shoots, and roots of tomato seedlings were significantly increased by chilling and drought stress. Activation of SOD and POD activity by chilling stress were higher in the roots than those of drought stress. However, activation of SOD and POD activity by drought stress were higher in the leaves and shoots than those of chilling stress. The specific and gel activity of GR in the leaves, shoots, and roots of tomato seedlings were also significantly increased by chilling and drought stress. When the seedlings were treated with chilling or drought stress, one GR isozyme band (GR-3) was newly expressed in the leaves of tomato seedlings. The specific and gel activity of PPO was significantly increased in the roots and shoots of tomato seedlings by chilling and drought stress, respectively. However, the specific and gel activity of PPO in the leaves is no difference between stressed and controlled tomato seedlings.

• Korean Journal of Organic Agriculture
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• v.28 no.1
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• pp.95-108
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• 2020

To develop an environment-friendly fungicide for controlling tomato wilt diseases, antifungal active substance was isolated Rheum australe D. Don roots against Fusarium oxysporum f. sp. lycopersici, a pathogen of tomato wilt, in this study. Methanol extract obtained from Rheum australe roots was successively fractionated with hexane, chloroform, ethyl acetate, butanol and water. The ethyl acetate fraction, which showed the highest antifungal activity, was separated by column chromatography, and 60 subfractions were obtained. The 60 subfractions were anlayzed for antifungal activities by bioassay. The active compound was identified as 5-[(E)-2- (3-hydroxy-4-methoxyphenyl)ethenyl]benzene-1,3-diol (rhapontigenin) by NMR and GC-MS analysis. As a result of testing antifungal activity of rhapontigenin against Fusarium oxysporum, EC₅₀ of rhapontigenin was showed strong antifungal activity at 7.48 mg/L. Therefore, this study showed that the Rheum australe roots extract can be a potential candidate which is a environment-friendly fungicide against Fusarium oxysporum.

• Journal of Ecology and Environment
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• v.29 no.1
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• pp.61-67
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• 2006

Tomato (Lycopersicon esculentum Mill) seedlings exposed to various concentrations of $CdCl_2(0{\sim}100{\mu}M)$ in a nutrient solution for up to 9 days were analyzed with respect to the thiol changes and oxidative stress. The Cd exposure increased total non-protein thiols (NPT) and cysteine in both leaves and roots, total glutathione in leaves, and the ratios of oxidized glutathione (GSSG)/reduced glutathione (GSH) in both leaves and roots, but decreased the ratio of dehydroascorbate (DASA)/ascorbate(ASA) in leaves. Our results suggest that the Cd-induced GSH depletion due to thiol synthesis and oxidation alters the antioxidant activity of seedlings for $H_2O_2$, and the subsequent $H_2O_2$ accumulationand oxidative stress result in phytotoxicity.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.181-183
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• 2003

Corky root symptoms caused by Pyrenochaeta lycopersici were observed on the roots and stem base of tomato plants in Korea. Symptoms on infected plants typically appeared as stunting and generally lacking vigor, and infected plants die back from the foliage tips after fruits have set. Brown lesions appearing with bands around the roots were characteristic symptoms of the disease. The lesions become swollen and cracked along the length of the root with corky appearance. Based on cultural and morphological characteristics, the fungus from the diseased plants was identified as Pyrenochaeta lycopersici. Pycnidia were solitary, globose to subglobose, brown to black, darker around the neck region, and measured 173-215 $\mu\textrm{m}$ in diameter with septate setae up to 102-132$\times$6.5 $\mu\textrm{m}$. Conidia were hyaline, unicellular, and 4.2-4.7$\times$l.5-2.0 $\mu\textrm{m}$ long. Optimum temperature for mycelial growth of the p. lycopersici isolates ranged from $20^{\circ}C$ to $25^{\circ}C$. Fifteen isolates off lycopersici were tested for pathogenicity to susceptible and tolerant cultivars of tomato plants by artificial inoculation. Three isolates of P. lycopersici induced typical corky root discoloration on susceptible tomato cultivars but not on tolerant tomato. This is the Erst report in Korea of tomato corky root disease caused by P. lycopersici.

• Journal of Plant Biology
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• v.30 no.1
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• pp.59-67
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• 1987

To verify allelopathic effect of tomato plants a number of labovatory experiments, seed germination and seedling growth with aqueous extracts and leachates form the tomato plants, have performed. Germination percentage of the tested species was decreased by treatment with leaf, stem and root extracts as extracting time elapses. The leaf extract more inhibits the germination of the seeds than both stem and root extracts. Leachate collected from the tomato plants decreases as much as 50% of the growths in elongation as well as dry weight of seedlings of lettuce and egg plant. It is observed that with a paired-plants grown in U tube pot the tomato roots have excreted allelochemicals to inhibit the growth of the tested species and volatile substances from the tomato plants have suppressed to dry weights of lettuce, to elongation and dry weights of grapevine planted near the tomato plants.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.252-260
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• 2014

Contents of carotenoids, phenolic compounds, volatile organic compounds, and alkaloids in leaves, internodes, fruits, and roots of tomatoes in different developmental stages were measured. Lycopene, ${\beta}$-carotene, and lutein were detected in all the tested parts except roots and green fruits. Lycopene content in red fruits was $49.04{\mu}g{\cdot}g^{-1}$ FW, while that in the other parts was below $40{\mu}g{\cdot}g^{-1}$ FW. ${\beta}$-Carotene and lutein contents in 24th leaves were 5.81 and $6.40{\mu}g{\cdot}g^{-1}$ FW, respectively, and were greater than those in the other parts. Caffeic, chlorogenic, and vanillic acids were detected in all the tested parts except roots. The content of chlorogenic acid in the 18th leaves was $40.11{\mu}g{\cdot}g^{-1}$ FW, while that in the other parts was lower than $31.00{\mu}g{\cdot}g^{-1}$ FW. The contents of caffeic and vanillic acids in the 24th leaves were 9.18 and $1.64{\mu}g{\cdot}g^{-1}$ FW, respectively, and were greater than those in the other parts. Moreover, younger leaves contained the more diverse volatile organic compounds including monoterpenes and sesquiterpenes. Contents of dehydro-tomatine and ${\alpha}$-tomatine were greatest in leaves, followed by internodes, roots and fruits. Younger leaves and internodes contained more dehydro-tomatine and ${\alpha}$-tomatine than older leaves and internodes. The contents of dehydro-tomatine and ${\alpha}$-tomatine in the 24th leaves were 0.89 and $1.42mg{\cdot}g^{-1}$ FW, respectively, and were greatest among all the tested parts. Our results indicated that, except lycopene, tomato leaves included greater secondary metabolites contents than red fruits. The results suggest that inedible parts of tomato plants can be used as raw material for antioxidants, anti-inflammatory agents, fungistats, and pesticides.

• Research in Plant Disease
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• v.23 no.4
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• pp.295-305
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• 2017

This study aimed to investigate the plant growth-promoting and biocontrol potential of a grass culture with Paenibacillus ehimensis KWN8 on tomato. For this experiment, treatments of a chemical fertilizer (F), a bacterial grass culture (G), a 1/3 volume of G plus 2/3 F (GF), and F plus a synthetic fungicide (FSf) were applied to tomato leaves and roots. The result showed that the severity of Alternaria solani and Botrytis cinerea symptoms were significantly reduced after the application of the bacterial grass culture (G and GF) and FSf. In addition, root mortality in G and GF was lower compared to F. Tomato plants treated with G or GF had better vegetative growth and yield compared to F. Application of G affected the fungal and bacterial populations in the soil. In conclusion, treatment with a bacterial grass culture decreased disease severity and increased tomato growth parameters. However, there were no statistically significant correlations between disease occurrence and tomato yields. This experiment presents the possibility to manage diseases of tomato in an environmentally friendly manner and to also increase the yield of tomato by using a grass culture broth containing P. ehimensis KWN38.

• The Plant Pathology Journal
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• v.21 no.3
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• pp.244-251
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• 2005

The induction of growth promotion on numerous crops by rhizobacteria is a well documented phenomenon. In case of tomato (Lycopersicon esculentum), fruit yield is higher in replant soil than that in fresh soil. To investigate what kind of rhizobacterium is involved, microbial community in rhizosphere and on rhizoplane of tomato plants from each soil was analyzed by dilution plating on selective media. Many Gram-negative bacteria and actinomycetes were isolated from tomato in replant soil. One Gram-negative rhizobacterium isolated was identified as Pseudomonas putida based on its biochemical characteristics, fatty acid methyl ester analysis and 16S rDNA sequence. This bacterium designated strain 17 inhibited the growth of Pseudomonas corrugata, and increased growth of tomato seedlings. In addition, its culture filtrate inhibited conidial germination of plant-pathogenic fungi such as Fusarium oxysporum f. sp. radicis-lycopersici, F. oxysporum f. sp. cucumerinum, and Nectria radicicola. Scanning electron microscopy revealed strain 17 colonized and persisted on the epidermal surfaces of tomato radicles and roots. These results suggest that P. putida strain 17 may serve as a biological control agent to suppress multiple soil-borne diseases for tomato plants. Increased microbial populations that suppress deleterious microorganisms including pathogens could be one of the major factors in increased tomato yield in replant soil.

• The Korean Journal of Ecology
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• v.22 no.2
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• pp.89-94
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• 1999

Thirty-day-old seedlings of tomato (Lycopersicon esculentum) were treated with different concentrations of HgCl$_2$(0. 10 and 50 $\mu$M) for up to 20 days. and the detailed distribution of Hg absorbed and its toxicity in different plant parts (roots, stems and leaves) were investigated. The accumulation of Hg in plants increased with external Hg concentrations. and Hg is strongly retained by roots. Further. Hg content in leaves was various. showing more accumulation in older leaves. Seedlings exposed to toxic levels of Hg showed not only the reduction of dry weight and length of both shoot and root. and chlorophyll levels in leaves but also the enhancement of malondialdehyde (a lipid peroxidation product) formation in all plant parts investigated. These results suggest that physiological impairment of a plant exposed to Hg may be achieved by internal distribution of Hg absorbed and Hg-induced oxidative stress in different plant parts.