• Horticultural Science & Technology
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• v.19 no.4
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• pp.526-529
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• 2001

The study was conducted to investigate quality changes of red pepper by different shelf temperatures after storage at $7^{\circ}C$ for 30 days. Red pepper fruits produced high volume of $C_2H_4$ and $CO_2$ when alternating temperatures exceeded $10^{\circ}C$. Total sugar contents were not different among all the treatments. In contrast, sucrose content decreased about half at higher shelf temperature conditions than at $7^{\circ}C$. Capsaicinoid content was not influenced by alternating temperature, but ascorbic acid content tended to decrease by high shelf temperature after storage at $7^{\circ}C$. Decay did not occur under $13^{\circ}C$, while it occurred in 22.2% of hits at $15^{\circ}C$ and 68.8% at room temperature, respectively. From this results, it is suggested that the optimum shelf temperature of red pepper after low temperature storage should be under $13^{\circ}C$ and that fruits of red pepper stored at $7^{\circ}C$ for 30 days could be sold within 10 days on the shelf.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.218-224
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• 2019

This study was conducted to compare the effect of salicylic acid (SA), an ethylene biosynthesis inhibitor, and the 1-methylcyclopropene (1-MCP) fumigation, to prevent fruit quality deterioration and physiological disorders during the shelf-life of Korea's leading export grape variety 'Campbell Early'. The berries treated with SA after 1-MCP fumigation (1-MCP+SA) showed a higher firmness value and titratable acidity than single treatment of SA or 1-MCP. The rate of shattered berry was high as 41.7% for 100ppm ethephon spray, 40.8% for $25{\mu}M$ SA, and 38.2% for 1,000ppb 1-MCP, but showing only 18.7% when the SA was applied after 1-MCP fumigation. The ratio of short brushes less than 1mm was largest at 74.3% for ethephon treatment, while 1-MCP+SA treatment was found to have the longest brush length among all treatments, with a 2-4mm ratio of 22.8% and a 4-6mm ratio of 27.9%. The weight of rachis was found to be the lowest at 2.3g in the ethephon treatment, and the reduction of rachis weight loss per cluster by 1-MCP+SA treatment was evident. In addition, 1-MCP+SA treatment were effective in mitigating stem browning and berry decay during the 16-day storage period at $19^{\circ}C$ in this cultivar, so it is believed that they can be used as a practical post-harvest treatment in grape exportation.

• Research in Plant Disease
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• v.22 no.2
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• pp.122-126
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• 2016

In June 2015, an exhibited typical signs and symptoms of brown rot was observed on fruit of Apricot cvs. Modern and Alexander at an incidence of 5% of fruit in Jeonju, Korea. Early symptoms on fruit showed small, circular, light brown spots that eventually destroyed the entire fruit. Small sporodochia appeared on the fruit surface. Fruit susceptibility to brown rot increases during the 1 to 2 weeks period prior to harvest. The conidia were one-celled, hyaline, lemon-shaped, $14.6-18.0{\times}8.5-11{\mu}m$, and borne in branched monilioid chains. Based on the morphological characteristics and phylogenetic analysis of internal transcribed spacer (ITS), the fungus was identified as Monilinia fructicola. A BLAST search revealed that sequences of the fungus shared 100% identity to those of M. fructicola. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch's postulates. To our knowledge, this is the first confirmed report on the occurrence of M. fructicola on apricot in Korea.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.362-366
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• 2001

This survey was carried out to investigate the effect of flooding by heavy rain on growth characteristics and disease incidence of 'Fuji'/M.26 mature apple tree in 1998 at Kyongbuk province. The surveyed regions were Andong, Uisung, and Gunwi area. The six orchards were selected from one area, totally 18 orchards were surveyed. The flooded depth of surveyed orchards was from 70 to 350 cm, and the flooded duration was from 6 to 72 h. Defoliation ratio, number of abnormal budding, and flowering per tree were increased along with the increment of flooded depth and duration. Rooting ratio was decreased rapidly with the increment of flooded duration, and dead root ratio was 16.2% in flooded orchards. Marssonia blotch (Diplocarpon mali), white rot (Botryosphaeria dothidea) of fruit, and phytophthora fruit rot (Phytophthora cactorum) incidence were increased in flooded orchards. The analysis results of pearson correlation coefficient among surveyed items showed that higher relationship of abnormal growth characteristics and increment of disease incidence of 'Fuji'/M.26 apple trees with flooded duration than with flooded depth. With these results, the flooded depth was found to be the main factor for the abnormal growth characteristics and disease incidences of 'Fuji'/M.26 apple trees.

• The Korean Journal of Mycology
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• v.36 no.2
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• pp.199-202
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• 2008

Rhizopus soft rot caused by Rhizopus stolonifer occurred on melon (Cucumis melo L.) in the box at Jinju City Wholesale Market of Agricultural Products at Gyeongnam province in Korea. The infected fruits were rapidly water-soaked, softened, black and eventually rotted. The symptoms were infected from wounds at harvest time. The colony were white to light brown, formed much sporangiospores. The optimum temperature of the fungus was $30^{\circ}C$. Sporangia were globose or hemispheric, white at first and gradually to black, and $80{\sim}195\;{\mu}m$ in size. Sporangiophores were $12{\sim}24\;{\mu}m$ in width. Columella were hemispheric, and $70{\sim}90\;{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black and $9{\sim}20\;{\times}\;6{\sim}8\;{\mu}m$ in size. On the basis of symptom, mycological characteristics and pathogenicity to melon, the causal fungus was identified as Rhizopus stolonifer (Ehrenb.) Vuill.. This is the first report of Rhizopus soft rot by R. stolonifer on melon in Korea.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.170-173
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• 2001

Postharvest diseases developed on harvested products result in a great economic loss. The objective of this research was to develop a chemical treatment to control major postharvest pathogens including Botrytis cinerea and Penicillium expansum in the cold storage room. Acetic acid ($2.4mg{\cdot}L^{-1}$, $4.8mg{\cdot}L^{-1}$) inhibits spore germination and mycelial growth of B. cinerea and P. expansum on PDA at room temperature ($25^{\circ}C$) and low temperature ($2^{\circ}C$). Fumigation of cold storage room with $SO_2$ ($5g{\cdot}m^{-3}$) gas or gaseous acetic acid ($4.8g{\cdot}m^{-3}$) prior to operation greatly reduced population of fungi in the cold storage room.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.42-49
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• 2012

This experiment was conducted to find out the effects of nitrous oxide ($N_2O$) on the postharvest quality of 'Janghowon hwangdo' peach fruits. Fruits were harvested at commercial maturity for marketing in late September, and treated with 70% $N_2O$ + 20% $O_2$ + 10% air, 80% $N_2O$ + 20% $O_2$, and 90% $N_2O$ + 10% $O_2$ for 48 h, and then stored at $15^{\circ}C$. No significant treatments for soluble sugar and titratable acidity contents were detected. However, good appearance and taste in peach fruit were maintained better in 80% $N_2O$ treatment than in air treatment. The treatment with 90% $N_2O$ had negative effects on weight loss and taste because of rotting by anaerobic fermentation. 80% $N_2O$ treated fruit had significantly higher fungus (Botrytis cinerea) growth inhibition of saprogenic approximately than air treatment until 12 days of storage. The browning and rotting at surface of peach were also retarded when peaches were treated with 80% $N_2O$ before they were artificially wounded. The activity of polyphenol oxidase (PPO) was inhibited about 80% in peach of 80% $N_2O$ treatment compared with in air treatment. The result showed that 80% $N_2O$ treatment was able to extend the shelf life of peach fruits through maintaining taste and inhibition of softening and browning by rotting and wounding during storage.

• Food Science and Preservation
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• v.10 no.1
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• pp.1-5
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• 2003

This study was carried out to extend a marketing shelf-life of the Jeju greenhouse mandarin fruits. Total soluble solids were not showed any significant differences by the temperatures and pre-treatments during the marketing period. Acid content and firmness of the fruits were gradually decreased, which were better in cold than in room temperature treatment. The fruits washed in electrolyzed acid water(pH 2.4∼2.7) maintained freshness higher than those of control Internal CO$_2$concentration of those was 1.0 ％ more or less in the beginning marketing stage, but increased along the marketing period in mom temperature. Especially Internal CO$_2$concentration of wax-coated fruits rapidly increased more than any other, whereas it was a little decreased in cold treatment. After 10 days in room temperature, decay ratio of the fruits was below 4.0% in electrolyzed acid water washing, compared to 10.4% in control. After 30 days in cold temperature, decay ratio was only 3.7% in electrolyzed acid water washing compared to 4.4% of wax-coated treatment and 7.4% of control. The weight loss among the pre-treatments in room temperature had no significant differences and was higher than in cold one.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.12-16
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• 2001

This study was conducted to evaluate the effect of calcium chloride treatment (0.1%, 0.3%, and 0.5%) in red sweet pepper 'Ace' on the improvement of shelf-life and the physiological characteristics. $C_2H_4$ production and respiration rates of fruits treated with $CaCl_2$ before harvest decreased during storage of red sweet pepper at $7^{\circ}C$. Ca contents in the leaves and in the fruits showed also a greater increase in treatment of $CaCl_2$ than that in control. No difference was found in total sugar, whereas sucrose content was rapidly reduced after 20 days at $7^{\circ}C$. Ascorbic acid contents were increased by the $CaCl_2$ treatment. As Ca concentration is getting higher, the fruit decay rate was significantly reduced. From this result, we can positively conclude that foliar application with the concentration of 0.3% $CaCl_2$ and 0.5% $CaCl_2$ before harvest is effective in improving storage quality in red sweet pepper.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.4
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• pp.538-544
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• 1997

To utilize abundant poor persimmon fruits effectively, It was studied on alcohol fermentation strains which were isolated and indentified from poor persimmon fruits. The strains which had exellent alcohol production ability were analysized morphogical, cultural characteristics and identified Saccharomyces cerevisiae YJK 20, Sacachromyces kluveri DJ 97. Alcohol production ability between the isolated strains and industrial alcohol yeasts was compared in the YPD medium, persimmon extract medium. Isolated strains had high alcohol production ability in both of two medium, respectively. So it was expected that the strains. YKJ 20 and DJ 97 had good alcohol fermentation ability of persimmon fruits.