• Journal of Plant Biology
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• 제38권3호
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• pp.235-242
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• 1995

Effects of methyl jasmonate (MeJA) on ethylene production in tomato(Lycopersicon esculentum Mill.) hypocotyl segments and fruits were studied. Ethylene production in tomato hypocotyl segments was inhibited by the increasing concentratons of MeJA, and 450 $\mu$M of MeJA showed 50% inhibitory effect. Time course data indicate that this inhibitory effect of MeJA appeared after 3 h of incubation period and continued until 24 h. Inhibition of ethylene producton by MeJA was due to the decrease in 1-aminocyclopropane-1-carboxylic acid(ACC) synthase activity. However, MeJA treatment had no effect on ACC oxidase activity and the accumulaton of ACC oxidase mRNAs. MeJA also inhibited auxin-induced ethylene production by decreasing in ACC synthase activity. In contrast, MeJA stimulated ethylene production in tomato fruits. When 30 $\mu$L/mL MeJA was treated in a gaseous state, ethylene production doubled and this stimulating effect continued until 4 days. To investigate the mechanisms of MeJA on ethylene production, ACC synthase and ACC oxidase activities were examined after MeJA treatment. MeJA increased the activities of both ACC synthase and ACC oxidase, and induced ACC oxidase mRNA accumulation. These data suggest that MeJA plays distinct roles in the ethylene production in different tomato tissues. It is possible that MeJA affects differently the mechanisms of signal transuction leading to the ethylene biosynthesis.

• 식물병연구
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• 제19권1호
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• pp.25-30
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• 2013

국내에서 시판되고 있는 토마토 36품종을 이용하여 국내 시설재배지에서 가장 많이 분포하고 있는 두 종의 뿌리혹선충, Meloidogyne arenaria와 M. incognita에 대한 저항성을 검정하였다. 방울토마토 중에서는 '텐텐', '캐딜락', '큐티', '스위트', '뽀또', '리코핀-9' 등 6품종, 완숙토마토 중에서 '러브리240', '도테랑다이아', '큐피랑', '도테랑마스터', '슈퍼도태랑', '도태랑시즌', '마이로꾸', '호용' 등 8품종, 대목은 '스페셜', '파이팅', '마그네트' 등 3품종이 두 종류의 뿌리혹선충에 모두 강한 저항성이었다.

• The Korean Journal of Ecology
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• 제27권2호
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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.

• The Korean Journal of Ecology
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• 제22권2호
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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.

• 한국환경농학회지
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• 제41권4호
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• pp.245-251
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• 2022

BACKGROUND: Selection an suitable light source is essential in the year-round production of horticultural crops in closed production systems such as plant factory with controlled environments. This study was investigated to confirm the effects of artificial light sources on growth of cherry tomato'CF Jelly'(Lycopersicon esculentum var.) under high-pressure sodium lamps (HPS), metal-halide lamps (MH), and LEDs. METHODS AND RESULTS: Light intensity of the light sources was controlled at 220±30 µmol/m²/s with 12 hrs of photoperiod for a day. Flower development was significantly faster in HPS and MH treatments compared to the LEDs. There was no significant difference between the leaf number and leaf shape under the HPS and MH treatments. Reproductive growth of cherry tomato was significantly promoted by the LEDs treatment of blue plus red lights. Fruit yield per plant also increased under the LEDs compared to the others. CONCLUSION(S): Growth, flowering, and fruit setting of the cherry tomato were accomplished by the artificial lights under plant factory conditions. The HPS treatment showed negative effect on fruit quality in terms of blossom-end rot incidence compared to the LEDs or MH treatment. Effect of the LEDs on promotion of fruit weight and yield was also proved. Additional research should be carried out for improving sugar metabolism or decreasing disease in the fruits under plant factory system using only artificial lights.

• 식물조직배양학회지
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• 제24권1호
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• pp.57-61
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• 1997

Superoxide dismutase (SOD) 고생산세포주로 선발된 토마토(Lycopersicun esculentum) 배양세포를 사용하여 현탁배양에 따른 SOD 활성과 isoenzyme변화를 조사하고 토마토 식물체의 것과 비교하였다. 현탁배양은 세포생중량 2 g을 1 mg/L 2,4-D, 30 g/L sucrose를 함유한 MS 배지 50 mL과 함께 mL flask에서 $25^{\circ}C$암상태로 배양(100 rpm)하였다. 세포생장은 계대배양후 20일에 최고점에 도달한 후, 급격히 감소하며 배양 후 23일부터 세포가 검게 변하였다. 세포 단위무게당 SOD활성(unit/g dry cell wt)은 배양 후 23일부터 증가하여 28일째에 최고활성(52,400 unit)을 나타낸 후 급격히 감소하였다. 세포 밖으로 분비되는 extracellular SOD활성은 배양 후 25일에 최고치(27,800 unit/so mL medium)를 나타낸 후 감소하였다. Flask 전체의 SOD활성은 배양 후 25일에 최대치(35,700 unit)를 나타내었으며 extracellular SOD 활성이 약 75%을 차지하였다. 토마토 배양세포에는 4개의 SOD isoenzyme이 존재하며, isoenzyme의 패턴변화는 세포생장에 따른 효소활성의 변화와 일치하였다. 토마토 식물체는 배양세포에 없는 CuZnSOD가 존재하며 배양세포와 식물체 조직사이에는 서로 다른 isoenzyme 패턴이 존재함을 알 수 있었다.

• Preventive Nutrition and Food Science
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• 제9권3호
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• pp.283-288
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• 2004

Superoxide dismutase (SOD) from tomato (Lycopersicon esculentum Mill.) fruit was purified by ammonium sulphate precipitation, Sephadex G-100 and DEAE-cellulose column chromatographies. A 22 fold purification and an overall yield of 44% were achieved. The purified enzyme was a homodimer with Mr 37.1 kDa and subunit Mr 18.2 kDa as judged by SDS-PAGE. SOD showed $K_{m}$ values of 25 ${\times}$ 10$^{-6}$ M and 1.7 ${\times}$ 10$^{-6}$ M for nitroblue tetrazolium (NBT) and riboflavin as substrates, respectively. The enzyme was thermostable upto 5$0^{\circ}C$ and exhibited pH optima of 7.8. The effect of metal ions and some other compounds on enzyme activity was studied. $Co^{2+}$ and $Mg^{2+}$ were found to enhance relative enzyme activities by 27 % and 73 %, respectively, while M $n^{2+}$ inhibited the SOD activity by 64%. However, $Ca^{2+}$ and C $u^{2+}$ had no effect on enzyme activity. Other compounds like $H_2O$$_2$ and Na $N_3$ inhibited enzymatic activities by 60% and 32%, respectively, while sodium dodecyl sulphate (SDS), chloroform plus ethanol and $\beta$-mercaptoethanol had no effect on the activity of SOD. of SOD.

• Mycobiology
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• 제30권4호
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• pp.244-246
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• 2002

A destructive stem rot of tomato(Lycopersicon esculentum) occurred sporadically some farmers' fields in Jinju City, Gyeongnam province in Korea. The infected plants also showed stem, crown rot or whole plant blight. White mycelium spread over stems of infected plants and formed sclerotia on the old lesions nearby soil surface. The fungus showed maximum mycelial growth around $30^{\circ}C$. The fungus formed white colony on PDA, usually with many narrow mycelial strands in the aerial mycelium and the width were $4.0{\sim}9.8{\mu}m$. The typical clamp connections were formed on the mycelium. Numerous sclerotia was formed on PDA at $30^{\circ}C$. The shape of sclerotia was globoid and $1.0{\sim}3.0$ mm in size. The fungus was isolated repeatedly from the infected tissues and the pathogenicity was confirmed to tomato and identified as Sclerotium rolfsii. This is the first report on the stem rot of tomato caused by S. rolfsii in Korea.

• 생물환경조절학회지
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• 제4권1호
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• pp.25-31
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• 1995

고형배지경에서 배양액농도가 토마토의 생육에 미치는 영향을 구명하고자 본 실험을 수행하였다. 배지는 펄라이트, 버미클라이트 및 피트모스를 사용하였으며, 묘들은 육묘기 때에는 0.5, 1, 2, 3 및 5mS/cm의 각기 다른 배양액농도로 재배되었고 정식후에는 1, 2 및 3mS/cm의 농도로 옮겨져 재배되었다. 육묘기 때에 배양액농도를 0.5mS/cm에서 3.0mS/cm로 높임에 따라 유묘의 광합성속도는 3가지 종류의 배지에서 모두 증가하였으며, 0.5-3.0mS/cm 범위 이상의 농도에서는 광합성속도가 감소하였다. 초장, 엽장, 엽폭, 경경 및 지상부 건물중은 펄라이트에서는 배양액농도를 0.5mS/cm에서 5mS/cm로 높임에 따라 계속 증가하는 경향을 보였으며, 버미클라이트에서는 2-5mS/cm에서 높았으며, 피트모스에서는 3mS/cm일 때 가장 높았다. 따라서 묘의 초기생장에 대한 배지별 적정배양액농도는 배지에 따라 차이가 있는데, 펄라이트에서는 3-5mS/cm, 버미클라이트와 피트모스에서는 각각 2-5mS/cm, 3mS/cm인 것으로 나타났다. 정식 후에 배양액농도를 1mS/cm에서 3mS/cm로 높임에 따라 3가지 종류의 배지에서 모두 건물중이 크게 증가하였다. 그러나, 육묘기와 정식 후에 계속하여 5mS/cm의 고농도로 재배한 것들의 건물중은 단지 조금 증가하였다.

• Journal of Ecology and Environment
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• 제29권1호
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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.