• Journal of Bio-Environment Control
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• v.10 no.1
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• pp.30-35
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• 2001

This experiment was undertaken to investigate the effect of root zone temperature during the night on absorption of mineral nutrients, growth, and fruit yield of the truss-limited hydroponic tomatoes in winter. The root zone temperature was either controlled to 10, 15, 20, $25^{\circ}C$, or left uncontrolled at ambient temperatures. Temperature of the covered beds rose as root zone temperature was raised, but it in all treatments was less than 3$^{\circ}C$ higher than that in the control. Raising root zone temperature, except $25^{\circ}C$, showed positive effect on plant height, leaf length, stem diameter, and plant fresh and dry weight, but not on T/R ratio which was the greatest in the control. Root activity in all treatments except $25^{\circ}C$ increased as compared to the control. Mean fruit weight, fruit count per plant, and fruit yield were the greatest in 2$0^{\circ}C$ treatment. Root zone temperature did not significantly affect the contents of total nitrate and magnesium in leaves, stems and roots. Concentrations of phosphate and calcium increased in leaves and stems, but decreased in roots as root zone temperature increased. Overall, 2$0^{\circ}C$ treatment gave the greatest growth and energy efficiency.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.18-22
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• 2007

The optimum production condition for the antibiotic from Bacillus thuringiensis BK4 was determined, and the suppression rate of Fusarium-wilt by the butanol-extracted antibiotic was verified by employing tomatoes in vitro and in vivo pot tests. Cell growth and antifungal activity were the best when 0.5% xylose and 0.2% peptone No.3 were given as carbon and nitrogen sources, respectively, in the presence of 5mM $CaCl_2$. The partially purified antibiotic successfully prevented Fusarium oxysporum pathogen in pot experiments. When the pots were treated with both live cells and the partially purified antibiotic, an additive-effect was seen in the suppression of Fusarium-wilt, but synergistic effect was not detected. The antibiotic, denoted BK4, purified by Sephadex LH-20 column chromatography was eluted with a single peak at a retention time of 38 min. on prep-HPLC; Minimum inhibition concentration of the homogenous antibiotic was determined to be 50${\mu}$g/ml.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.2
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• pp.47-58
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• 1984

The study results of the mosture consumption character and irrigation effect of tomato, red pepper and chinese cabbage, in case the soil moisture is kept with different moisture content by the soil properties(loam, sandy loam, sand), are summarized as follows: 1. The available rainfall under bare soil condition had an order of sand>sandy loam> loam and their average was 64.2%. 2. Total moisture consumption under bare soil condition had an order of loam>sandy loam>sand and their average was 4.2mm. 3. The amount of irrigated water to keep certain soil moisture under bare soil condition showed minimum in sand and maximum in loam. It is considered because the capillary phenomenon was more developed in loam. 4. Total moisture consumption of tomatoes under premature cultivation showed 925mm in maximum and had on order of loam>sandy loam>sand. In the aspect of re-irrigation point, it had an order of PF 1.5> PF 1.7>PF 2.1. In case the twenty years's drought frequency was taken into account, the target amount of irrigation water meeded for premature cultivation was 916mm and its average daily moisture consumption was 10.8mm. 5. Total moisture consumption of red pepper under open cultivation showed 1145mm in maximum and had an order of loam>Sandy loam>sand. In the aspect of re-irrigation frequency was taken into consideration the target amount of irrigation water was 1,174.8mm and its average daily moisture consumption was 8.0mm. 6. Total moisture consumption of autumn chinese cabbages was 349mm in maximum and had an order of loam>sandy loam>sand. In the aspect of re-irrigation point, it had an order of PF 1.5>PF 2.1>PF 2.7. In case the twenty year's drought frequency was taken into account, the target amount of irrigation water needed for chinese cabbage cultivation was 259.5mm and its average daily moisture consumption was 6.5mm. 7. It is effective to keep the soil moisture of tomato from PF 1.5 to PF 2.1 in loam and the soil moisture control was effective in sandy loam than red pepper and chinese cabbage. In sand, the production was severaly decreased and the re-irrigation point of PF 1.5 was effective.

• Research in Plant Disease
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• v.21 no.2
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• pp.99-102
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• 2015

Cucumber mosaic virus (CMV) is one of the most destructive viruses in chilli pepper. An isolate of CMV was obtained from the chilli pepper cv. Chungyang showing top necrosis symptom in 2013 and designated as CMV-GTN. CMV-GTN was compared with the well-characterized isolate, CMV-Ca-P1, by investigating their amino acid sequences of the coat protein (CP) and biological reactions in several host plants. The CP of CMV-Ca-P1 composed of 217 amino acids but that of CMV-GTN composed of 218 amino acids by including additional valine in the $57^{th}$ amino acid position. Amino acid sequence similarity of the CP gene among CMV-GTN and other CMV isolates recorded in the GeneBank database ranged from 96% to 99%. CMV-GTN was selected as a representative isolate to screen the resistance pepper cultivars to CMV because it was highly pathogenic to tomatoes and peppers upon biological assays. The virulence of CMV-GTN was tested on 135 pepper cultivars which has been bred in Korea and compared with that of CMV-Ca-P1. Only the cv. Premium was resistant and three cvs. Hot star, Kaiser, and Good choice were moderately resistant to CMV-GTN, whereas two cvs. Baerotta and Kaiser were resistant to CMV-Ca-P1.

• Research in Plant Disease
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• v.24 no.3
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• pp.213-220
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• 2018

We classified the previously reported antagonistic strains of Sorangium cellulosum into 5 subspecies (A-E). Four strains were antagonistic to Botrytis cinerea (AB group) and two strains were antagonistic to Colletotrichum acutatum (AC group). According to the genetic and sequential analyses with standard genes, xynB1, bglA2, groEL1 for grouping, all strains of AB group were belonged to subspecies C and all strains of AC group were belonged to subspecies D. In addition, high pressure liquid chromatography with the culture filtrates confirmed the genetic results, because AB group had peaks with retention time at 20-22.5 minutes, whereas AC group had no peak. There was positive relationship ($R^2=0.9652$) between the control values of infecting B. cinerea on cherry tomatoes and the main peak areas of chromatograms among the four isolates of AB group. From the subspecies results of AB group, the main peak of KYC 3270 was expected to be epothilone D. However the retention times of the standard of commercial epothilone D and the main peak of KYC 3270 culture filtrate were different as 9.9 and 11.581 min., respectively. Finally, the antagonistic metabolite of AB group was inferred as 7-ketone epothilone D.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.549-555
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• 2010

Here we focused on tip-burn and blossom-end rot (BER) symptoms in the tomato plants expressing the constitutively active form of $Ca^{2+}/H^+$ antiporter (sCAX1) and/or a Ca-binding protein (calreticulin, CRT) genes during their whole growth period. Conclusively we demonstrated that CRT is able to suppress the tip-burn and BER symptoms that were induced by sCAX1. Under poor nutrition condition, tomato plants overexpressing sCAX1 showed severe necrotic collapses in both roots and shoot polar tissues, which are in accordance with $Ca^{2+}$ deficient symptoms frequently observed in an agricultural cultivation of tomato. Reciprocal grafting trials using sCAX1 and wild type plants revealed that the tip-burn symptom by sCAX1 overexpression is not caused by hindrance of $Ca^{2+}$ uptake from soil. We constructed CRT overexpressing transgenic tomatoes, and crossed them with sCAX1 transgenic plants to investigate the effects of CRT on the symptoms of sCAX1 transgenic plants. Co-expression of sCAX1 and CRT significantly suppressed the $Ca^{2+}$ deficient symptoms of sCAX1 transgenic plants. Those results suggest the model that $Ca^{2+}$ homeostasis disturbed by the overexpression of sCAX1 may be suppressed by the co-expression of CRT.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.166-170
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• 2008

The effects of heat treatments on the antioxidant activities of selected fruits and vegetables were investigated by heating at various temperatures (110, 120, 130, 140, and 150$^{\circ}C$) for 2 hr. The examined fruits and vegetables included tomatoes (Lycopersicon esculentum), oriental melon (Cucumis melon var. makuwa), apples (Malus pumila Miller var. domestica Schneider), melon (Cucumis melon), watermelon (Citrullus vulgaris), and banana (Musa sapientum). The total polyphenol and total flavonoid contents of the juices from heated samples were quantified spectrophotometrically, and their antioxidant activities were determined using DPPH and ABTS radicals. As the heating temperature increased, antioxidant activity also increased. The highest total polyphenol content (2.80 mg/g) occurred in the oriental melon with heating at 150$^{\circ}C$, and this value was 7 times higher than that of the untreated oriental melon (0.40 mg/g). The highest total flavonoid content (148.80 ${\mu}$g/g) occurred in the melon heat treated at 150$^{\circ}C$, and this value was 37 times higher than that of the untreated melon (4.54 ${\mu}$g/g). DPPH radical-scavenging activity was the highest in the watermelon treated at 150$^{\circ}C$ (84.37%, 0.50 mg/g), and this value was 40 times higher than that of the untreated watermelon. Finally, the highest ascorbic acid (AA) equivalent antioxidant capacity (AEAC) value (239.50 mg AA eq/g) was obtained in the watermelon heat treated at 150$^{\circ}C$ for 2 hr (control = 18.35 mg AA eq/g).

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.183-190
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• 2020

This study was conducted to investigate the physicochemical and functional properties of Gochujang in the presence of fermented tomato products. To accomplish this aim, tomatoes were fermented using Bacillus subtilis SRCM100333, and the products were used with Gochujang. As a control, non-fermented tomato liquid was used with Gochujang. There were no significant differences in quality characteristics except for amino nitrogen in Gochujang. The functional properties of tomato liquid (TL), fermented tomato product (FTP), Gochujang made with tomato liquid (TLG), and Gochujang made with fermented tomato products (FTG) were investigated. There were significant differences in the pancreatic lipase inhibition (PLI) and superoxide scavenging activity between FTP (87% and 28%, respectively) and TL (77% and 14%, respectively). Nitric oxide scavenging activity of FTG (52%) was higher than that of other groups (TL, FTP, and TLG). Overall, the results indicate that the fermented tomato can be used to develop functional Gochujang.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1271-1277
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• 2000

The extracts from tomatoes, apples, carrots, mallows, watercreses+pine needles, Angelica keiskei Koiz, jujubes and lemons were selected and mixed at the ratio of 3 : 3 : 3 : 1/2 : 1/2 : 1/2 : 1/2 : 1/5 on the basis of sensory evaluation. The mixed extracts were divided into three lots and treated as follows. The first lot was heated for 15 sec at $96^{\circ}C$ without centrifugation and filtration, the second filtered through a ultramembrane filter. For the third one, the ultrafiltrate combined with autoclaved retentates on the membrane filter and the previous centrifugal precipitation. The mixed juices were stored in the glass bottles with atmosphere or in film package with nitrogen gas. And then they were stored at $4^{\circ}$ and $20^{\circ}C$. During storage the treated juices showed $pH\;4.07{\sim}4.10$, titratable acidity $66.35{\sim}84.08$, soluble solid $7{\sim}9^{\circ}Brix$, reducing sugar $5.42{\sim}6.97%$, glucose $1.96{\sim}2.30%$ and fructose $3.46{\sim}4.14%$. The ultrafiltered juices showed yellow color, different from orange color of other treatment lots. Peroxidase activity and microbial population were inhibited by thermal treatment and ultrafiltration. The browning effects of the mixed juice of fruits and vegetables during storage were caused by ascorbic acid oxidation and non-enzymatic browning reaction, which could be reduced by change and packing with nitrogen gas instead of atmosphere inside bottles.

• Horticultural Science & Technology
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• v.29 no.1
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• pp.36-42
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• 2011

This research was conducted to investigate the effects of irrigation quantity in irrigation management system controlled by drainage level sensors for perlite bag culture on the growth and yields of tomatoes during different growth stages. Tomato plants were irrigated with four selected methods; supplying small quantity (~70 mL) during entire growth (S-S), large quantity (~145 mL) during entire growth (L-L), small quantity before harvesting the first cluster fruits and large quantity after harvesting (S-L), and large quantity until harvesting the first cluster fruits and small quantity after harvesting (L-S). The irrigation quantity supplied in each time was gradually adjusted along with the ratios as the tomato crop grew during different growth stages. The growth of the tomato plants was unstable and slow during the entire cropping period when the plant was irrigated by small or large quantities (S-S or L-L). In L-S treatment, the growth phase of the tomato was changed from vegetative to generative growth on the basis of the plant development index when each irrigation quantity was changed. The L-S treatment exhibited the largest root volume and yields with stable drainage ratios. Therefore, the optimum irrigation quantity was determined as 145 mL before harvesting the first cluster fruits and 70 mL after harvesting.