• Food preservation and processing industry
• /
• v.3 no.1
• /
• pp.42-46
• /
• 2004

Quality of fresh-cut tomato slices was compared during cold storage under various modified atmosphere packaging conditions. Chilling injury of slices in containers sealed with Film A was higher than with Film B; these films had oxygen transmission rates of 87.4 and 60.0 ml h-1 m-2 nun-1 at $5^{\circ}C$ and $99\%$ RH, respectively. While slices in containers with an initial atmospheric composition of air, $4\%$ CO2 + 1 or $20\%\;O_2, \;8\%\;CO_2+1$ or $20\%\;O_2$, or $12\%\; CO_2+\;20\%\;O_2$ showed fungal growth, slices in containers with $12\%\;CO_2 +\;1\%\;O_2$ did not. Low ethylene in containers enhanced chilling injury. Modified atmosphere packaging provided good quality tomato slices with a shelf-life of 2 weeks or more at $5^{\circ}C$. Experiments were conducted to compare changes in quality of slices of red tomato (Lycopersicon esculentum Mill. 'Sunbeam') fruit from plants grown using black polyethylene or hairy vetch mulches under various foliar disease management systems including: no fungicide applications (NF), a disease forecasting model (Tom-Cast), and weekly fungicide applications (WF), during storage at $5^{\circ}C$ under a modified atmosphere. Slices were analyzed for firmness, soluble solids content (SCC), titratable acidity (TA), pH, electrolyte leakage, fungi, yeasts, and chilling injury. With both NF and Tom-Cast fungicide treatments, slices from tomato fruit grown with hairy vetch (Vicia villosa Roth) mulch were firmer than those from tomato fruit grown with black polyethylene mulch after 12 days storage. Ethylene Production of slices from fruit grown using hairy vetch mulch under Tom-Cast was about 1.5- and 5-fold higher than that of slices from WF and NF fungicide treatments after 12 days, respectively. The percentage of water-soaked areas (chilling injury) for slices from tomato fruit grown.

• Journal of Plant Biotechnology
• /
• v.7 no.1
• /
• pp.57-65
• /
• 2005

The $F_1$ hybrid Red Coat is one of the most highly sought after cultivars of tomato in Australia and yields up to 7.5 $\cal{kg/plant}$. An experiment was conducted to de-termine the optimal strength and type of growth medium and sucrose concentration for shoot organogenesis of the Red Coat cultivar using cotyledonary explants. Two basal growth media, viz. MS and Gamborg' s $B_5$ at 0, 1/4, 1/2, full or double strength along with sucrose concentrations of 0, 0.5, 1.5, 3 or $5\%$, were evaluated using 25 replications. The main effects of treatment and their mutual interactions were evaluated for the proportion of explants that produced callus and/or shoots, number of shoots produced per explant, callus diameter and shoot height. The explants failed to produce shoots in the absence of mineral nutrient. Only a small proportion of the explants ($6\%$ with $B_5\;and\;3\%$ with MS) regenerated shoots in the absence of sucrose. Lower sucrose concentrations ($0.5-1.5\%$) along with full strength media were optimal for most of the traits studied. The $B_5$ medium outperformed MS medium for shoot organogenesis. For all the traits examined, significant differences in main effects (P < 0.05) and two-way interactions were detected, but no three-way interactions (medium type $\times$ medium concentration $\times$ sucrose concentration) were observed. Sucrose was found essential for the development of chlorophyll. Chlorophyll content increased with an increase in sucrose concentration up to $3\%$ and decreased at $5\%$ sucrose.

• Research in Plant Disease
• /
• v.22 no.1
• /
• pp.55-58
• /
• 2016

A Cucumber mosaic virus (named CMV-Tr1) isolated from the white clover (Trifolium repens) showing mosaic and malformation that found in a pepper field. Cucumber mosaic virus was identified through confirmation with PT-PCR, PCR-restriction fragment length polymorphism, and sequence analysis of coat protein (CP) gene. CMV-Tr1 mosaic symptom on the upper leaves of five tobacco species including Nicotiana benthamiana, Cucumis sativus, Physalis angulata, and Solanum lycopersicon. In Chenopodium quinoa and Vigna unguiculata the isolate showed local lesions in inoculated leaves. CMV-Tr1 compared with CMV-As in the sequence identity of CP gene. CMV-Tr1 showed 98.9% and 99.5% homologies at nucleotide and amino acid levels, respectively. Phylogenetic analysis of the CP gene indicated that CMV-Tr1 belongs to the CMV subgroup IB base on the CP. To our knowledge, this is the first report of CMV in T. repens in Korea.

• Research in Plant Disease
• /
• v.20 no.2
• /
• pp.107-111
• /
• 2014

A greenhouse experiment was conducted to examine the effect of initial population density (Pi) of Helicotylenchus dihystera on six commercial tomato cultivars. Two-week-old tomato seedlings of six commercial cultivars were transplanted in d-10-cm clay pot and was inoculated with to give 0, 0.02, 0.2, and 2 nematodes/g soil. Plants were grown in a greenhouse for 60 days. Root and plant weights were unaffected but plant height declined only at inoculum level of 2 nematodes/g soil. At the highest initial population density (2 nematodes/g soil), plant height of tomato cv. Poseidon was reduced by 24%. Tomato cv. Hoyong produced the most nematodes with 7.0 nematodes/g soil and the least was tomato cv. Miniheuksu with 2.2 nematodes/g soil.

• Korean Journal of Soil Science and Fertilizer
• /
• v.39 no.2
• /
• pp.80-85
• /
• 2006

The foliar injuries and absorption rates of calcium compounds in tomato (Lycopersicon esculentum cv. momotaro) and citrus [Shiranuhi(C. Marc. ${\time}C$. sinensis Osbeck)${\time}C$. reticulata Blanco)] were investigated. 0.3, 0.5 and 1.0% of $CaCl_2$, $Ca(NO_3)_2$, $Ca(H_2PO_4)_2$, Ca-EDTA, Ca formate or Ca acetate solution were applied to the leaves of tomato and citrus. The leaf burns were observed only in the foliar applications of Ca-EDTA and $Ca(H_2PO_4)_2$. Ca-EDTA exhibited more serious foliar injury than CaH2PO4. As applied with $^{45}CaCl_2$, $^{45}Ca(NO_3)_2$, $^{45}Ca$ formate or $^{45}Ca$ acetate, the rates of Ca absorptions by tomato and citrus leaves for 7 days were 17 to 32% and 6.6 to 46%, respectively. It meant that the absorption was differently influenced on calcium compounds. In tomato, the order of Ca foliar absorption was $Ca(NO_3)_2$ > Ca formate = $CaCl_2$ > Ca acetate. Although there was no difference in Ca absorption between the adaxial and abaxial parts of tomato leaves, total absorption was greater in expanded leaves than in expanding ones. On the other hand, in citrus Ca foliar absorption from $Ca(NO_3)_2$ or Ca formate was more active than that from $CaCl_2$ or Ca acetate. In conclusion, $Ca(NO_3)_2$ and Ca formate are recommended for the foliar application of Ca in tomato and citrus in order to increase absorption of Ca into their leaves.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• v.4 no.4
• /
• pp.231-240
• /
• 2000

Effects of Jasmonic Acid and Wounding on Polyphenol Oxidase Activity in Senescing Tomato Leaves The effects of jasmonic acid(JA) and wounding on polyphenol oxidase(PPO) during leaf senescence was investigated by measuring the PPO activity in detached tomato(Lycopersicon esculentum Mill.) leaves of two-week-old seedlings. The PPO activity in the detached senescing leaves increased significantly in the dark. The leaf segments responded to the application of JA with accelerated senescence, as indicated by the loss of chlorophyll and rapid increase in the PPO activity. The senescence-promoting action of JA differed in the light and dark. Wounding the detached senescing leaves by scraping surface segments or making punctures with needles considerably delayed the loss of chlorophyll and had a significant effect on the PPO activity, the amounts of which were roughly proportional to the intensity of the wounding. In the dark, the combination of wounding plus JA resulted in stable levels of chlorophyll and PPO. JA and ABA acted similarly in both unwounded and wounded leaves, however, the amount of chlorophyll and PPO in the wounded segments was always higher than in the respective controls. JA was found to eliminate the senescence-retarding action of benzyladenine. In a histochemical localization test, the PPO activity was found to be localized in the cell walls of the parenchyma tissue, thereby indicating moderate cytoplasmic reactions. In the JA-treated plants, the PPO activity was intense in the cells of the cortex and phloem parenchyma. Accordingly, based on these observations it would appear that PPO is a component of a defense response maker, whereas JA plays an integral role in the intracellular signal transduction involved in inducible defense mechanisms.

• BMB Reports
• /
• v.41 no.10
• /
• pp.693-698
• /
• 2008

The full-length cDNA of LebZIP2 (Lycopersicon esculentum bZIP2) encodes a protein of 164 amino acids and contains a N-terminal basic-region leucine zipper domain. Analysis of the deduced tomato LebZIP2 amino acid sequence revealed that it shares 85% sequence identity with both tobacco bZIP and pepper CcbZIP. LebZIP2 mRNA is expressed at a high level exclusively in flowers. Presently, LebZIP2 was strongly increased also following NaCl and mannitol treatments. No significant LebZIP2 expression was evident following cold treatment. Transient LebZIP2 overexpression resulted in increased NbNOA1 and NbNR transcript levels in Nicotiana benthamiana leaves. Our results indicate that LebZIP2 might play roles as an abiotic stress-signaling pathway and as a transcriptional regulator of the NbNOA1 or NbNR genes.

• Journal of Plant Biotechnology
• /
• v.33 no.4
• /
• pp.289-295
• /
• 2006

This study was carried out to evaluate the suitability of simple sequence repeat (SSR) markers for varietal identification and genetic diversity in 28 commercial tomato varieties. The relationship between marker genotypes and 28 varieties was analyzed. Of the 219 pairs of SSR primers screened against ten tomato varieties, 18 pairs were highly polymorphic with polymorphism information content (PIC) ranging from 0.467 to 0.800. Among the polymorphic loci, two to nine SSR alleles were detected for each locus with an average of 3.3 alleles per locus. Genetic distances were estimated according to Jaccard's methods based on the probability that the amplified fragment from one genotype would be present in another genotype. These varieties were categorized into cherry and classic fruit groups corresponding to varietal types and genetic distance of cluster ranging from 0.35 to 0.97. The phonogram discriminated all varieties by marker genotypes. The SSR markers proved to be useful variety identification and genetic resource analysis of tomato.

• Korean Journal of Environmental Agriculture
• /
• v.17 no.1
• /
• pp.34-38
• /
• 1998

To test a potential salt tolerance in phosphorus (P) efficient plants (T9 and T8), tomato seedlings were hydroponically grown in saline media. The tolerance was evaluated by comparing growth and metabolism against T5, non-P-efficient variety, at different salt concentrations: 0, 1, 5, 10 g/L. Fresh weights (FW) were measured weekly. Dry weight (DW), mineral contents, and stomatal resistance (Rs) were measured at the termination of experiment. At the lower two salt concentrations (0, 1 g/L), no significant difference was observed in terms of FW, DW, and Rs. At 5, 10 g/L of salt concentration, however, significant variation is evident: T9 and T8 outperformed T5. On the other hand, no difference was also in N, P, K, and Na contents at the corresponding salt concentration. These observations together indicate that P-efficient strain can better tolerate to salinity.

• Horticultural Science & Technology
• /
• v.16 no.4
• /
• pp.511-513
• /
• 1998

Tomato fruits(Lycopersicon esculentum $M_{ILL}$.) picked at mature (from mature green to breaker) and ripe (from pink to red) stage were packed into two layers in corrugated fiberbox and transported 200km and 400km from the harvested site. Loss (abrasion + cracking) in marketability was lowest (11.0%) from mature + 200km transport, followed by mature + 400km transport(13.5%), ripe + 200km transport(28.5%), and ripe + 400km transport (45.5%). When data were pooled by fruit maturity, firmness of mature fruit was 1.55 times higher than ripe fruit. However, vitamin C content was 1.25 times higher in ripe fruit than in mature fruit. Fruit transported longer distance and packed in bottom layer within a box exhibited lower firmness and vitamin C content in both maturity. It was concluded that it is desirable to transport relatively shorter distance for ripe tomato and longer distance for less ripe fruit.