• Research in Plant Disease
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• v.22 no.1
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• pp.18-24
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• 2016

This study was conducted to elucidate the cultural and pathogenic characteristics of Cladosporium cucumerinum PT1 and resistance of 81 commercial cucumbers (Cucumis sativus). Cucumber leaves and fruits appeared as scab were collected from a plastic film house located in Pyeongtaek, Gyeonggi-province, Korea in late March, 2015. A casual fungus was isolated from the diseased fruits on potato dextrose agar and it was identified as C. cucumerinum PT1 based on the morphological characteristics. To find out the effect of wounding and fruit size on the development of cucumber scab, small (<10 cm long), medium (10 to 20 cm long), and large (>20 cm long, commercially mature fruit) size cucumber fruits were harvested, C. cucumerinum PT1 pathogens were inoculated with a single droplet of suspension ($1{\times}10^5$ spores/ml) on wounded or unwounded cucumber fruits. Small fruits were completely damaged with showing severe water-soaking symptoms and fast pathogen growth regardless of wounded or unwounded. Meanwhile slight water-soaking symptoms on medium and large size fruits occurred and disease development into plant tissues was observed only on wounded fruits. Disease resistance of 81 commercial cucumber cultivars was evaluated on third-stage seedlings and small fruits by inoculating suspension ($1{\times}10^5$ spores/ml) of C. cucumerinum PT1. As a result, mini and pickling cultivar groups were resistant, 'Cheoeumcheoreom' cultivar was symptomless and the other cultivars were resistant to medium resistant. On the other hand, most of cucumber cultivars belonging to the other groups were susceptible. Disease resistance of cucumber against cucumber scab was significantly different among cultivars and a few cucumber cultivars showed different disease resistant responses to two bioassay methods using seedlings and small fruits. Therefore, to screen scab resistance in cucumber, a test using both fruits and seedlings is advisable. We think that the selected resistant cultivars can be used to control cucumber scab effectively under the farmhouse condition.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.9-20
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• 2017

Incidence of leaf blast on nursery plants and pitting disease on maturing banana bunches has been recorded in banana plantations during rainy season in Eastern India during 2014 to 2015. Taxonomical identification as well as DNA sequence analysis of the internal transcribed spacer region of fungus isolated from affected tissue culture derived plantlets and fruits confirmed the pathogen to be Pyricularia angulata Hashioka "in both the cases". Koch's postulates were proved on young plantlets as well as on maturing fruits of cv. Grand Naine under simulated conditions. Evolutionary history was inferred and presented for our P. angulata strain PG9001 with GenBank accession no. KU984740. The analysis indicated that the P. angulata is phylogenitically distinct from other related species related to both Pyricularia and Magnaporthe. Detailed symptoms of blast lesions on young leaves, transition leaves, mid rib, petioles, peduncle, maturing bunches, bunch stalks and cushions were documented. Notably, the distinct small pitting spots on maturing bunches reduced the visual appeal of mature fruits. Appearance of pitting symptoms on fruits in relation with age of fruits and their distribution pattern on bunch and fingers was also documented in detail. Further, the roles of transitory leaves, weed hosts, seasonality on disease occurrence have also been documented.

• Research in Plant Disease
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• v.27 no.2
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• pp.70-75
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• 2021

The abnormal brown sunken lesions were observed on cv. RubyS apple fruits in an orchard located in Gunwi, Gyeongbuk province, Korea. The primary observed symptoms such as small round sunken lesions and small black dots on the symptomatic area were different from the reported apple diseases. The affected apple fruits were sampled and subjected to isolation of the causal agent. Cultural and morphological characteristics of isolated fungal strain, designated KNUF-20GWA4, were similar to that of Colletotrichum spp. Based on multilocus sequence analyses using internal transcribed spacer regions and partial sequences of β-tubulin, glyceraldehyde-3-phosphate dehydrogenase, chitin synthase, and actin genes, strain KNUF-20GWA4 showed 99.2-100% similarities with C. aenigma ICMP 18608 and the isolate clustered together with several other strains of this species in the phylogenetic tree. To our knowledge, this is the first report of bitter rot on apple fruits caused by C. aenigma.

• Journal of Biosystems Engineering
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• v.17 no.3
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• pp.260-271
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• 1992

Fruits are generally subjected to mechanical forces during harvesting, handling, and transportation that may cause damage in the form of bruises, punctures, and cracks. In order to prevent damage, and insure better quality fruits for consumers, it is very essential to study physical properties of these materials. The studies were conducted to examine the effect of storage period, storage condition, and other factors, such as loading rate and initial strain, on the stress relaxation behavior of the fruit flesh, and develop nonlinear viscoelastic models to represent its stress relaxation behavior. The following results were obtained from the study : 1. Since the viscoelastic behavior of the fruits flesh was nonlinear, the behavior was satisfactorily modelled as follows ; $${\delta}({\varepsilon},\;t)={\varepsilon}^A[B\;{\exp}(-Ct)+D\;{\exp}(-Ft)+G(-Ht)]$$ But, for the every strain applied, the stress relaxation behavior of the fruit flesh, such as apple and pear, could be well described by the Generalized Maxwell model, respectively. 2. The effect of loading rate on the stress relaxation behavior was remarkable. The higher loading rate resulted in the higher initial stress, and the faster stress relaxation. 3. The higher initial strain resulted in the higher initial stress, and stress relaxed at the large initial strain was also much higher than at the small initial strain. 4. Stress relaxation rate and quantity stored in the fruits at the low temperature storage were much higher than those at the normal temperature storage in the same storage period. Also, in all fruits tested, the longer storage period was the more relaxation rate and quantity were shown. These trends in the normal temperature condition was the more significant than in the low temperature condition.

• International Journal of Advanced Culture Technology
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• v.7 no.2
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• pp.144-150
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• 2019

Recently, an increasing number of urban farmers are growing fresh vegetables and fruits themselves using urban garden or weekend farms. In other words, this is called urban agriculture. After the Industrial Revolution in the 18th century, the agricultural society changed from an agricultural society to an industrial society, and the population began to flock to the cities. With the continued increase of urban population, countries with abundant capital were able to control the distribution structure of food supplies and trade agreements among countries. Since energy consumption and carbon dioxide emissions caused by agricultural product movements have emerged as the main culprits of global warming, and our table is threatened by safety due to food supply that has no genetic modification or knowledge of the cultivation process, urban agriculture is already taking hold in the West. In other words, as agriculture met cities, its role grew. Each region actively conducts agricultural activities for raising poultry as well as growing vegetables and fruits by using flower beds of detached houses in the city center, rooftops of high and low buildings, or school playgrounds and small tributaries of land. The purpose of this study is to analyze and understand the significance and type of urban agriculture and to examine the cases of domestic and foreign urban agriculture based on this and to seek the developing direction of urban agriculture, which is gradually increasing. Tired of growing competition and rapid change, urbanites are seeking health and relaxation and are planning to present development measures for urban farming and conduct follow-up research to ensure safe food.

• Journal of Food Hygiene and Safety
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• v.23 no.3
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• pp.177-181
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• 2008

Mycotoxins produced by molds isolated from discolored sun-dried red pepper fruits were determined and the toxicity to animals was also tested by feeding mold-grown unpolished rice to rats. Among the mold species tested, only Alternaria alternata was toxic to experimental animals, while other mold species belonging to the genera of Colletotrichum, Diaporthe, Diaporthopsis, Botryosphereia, Aspergillus and Fusarium were not. Rats fed Alternaria-grown rice lost weight and died within two weeks of feeding period. Succumbed rats during the process of feeding study showed extreme cases of enlargements of stomach, small intestine and liver. Among the 17 Alternaria isolates, 8 species produced considerable amount of tenuazonic acid along with small amounts of other toxins including alternariol and monomethyl ether derivative of alternariol in both red pepper homogenate and unpolished rice. It is therefore advised that red pepper fruits infested by molds during the sun-drying process be discarded to avoid unnoticeable health hazards.

• The Korean Journal of Mycology
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• v.42 no.4
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• pp.353-356
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• 2014

In August 2013, brown rot was observed on cherry fruits (Prunus avium L.) in Hwaseong city, Korea. Fruit rot first appears as small, circular brown spots that increase rapidly in size causing the entire fruit to rot. Grayish spores appear in tufts on rotted areas. Based on these morphological characteristics, the two isolates were identified as Monilinia fructicola. Molecular analysis of 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) was performed to confirm the identification. The ITS sequences had 100% identity with those of other reference M. fructicola isolates of NCBI GenBank. Pathogenicity was tested using spore suspension inoculation on wounded or unwounded cherry fruits. The lesions were observed on wounded and unwounded fruits after inoculation for 7 days. This is the first report on M. fructicola causing brown rot on cherry fruits in Korea.

• Journal of Food Hygiene and Safety
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• v.17 no.2
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• pp.101-105
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• 2002

A total of 53 vegetables and fruits, consisting of 23 leaf vegetables, 4 fruits vegetables, 4 edible roots,7 spice vegetables and 15 fruits were analyzed for contents of nitrate and nitrite by ion chromatography. Nitrite was detected 10 of 23 kinds of leaf vegetables, which was dominant in lettuce by average 349.9 mg/kg. Nitrate contents of leaf vegetables were average 578.3 mg/kg, 415.7 mg/kg, 348.6 mg/kg in wild plant, mustard leaf and chinese vegetable, respectively. Nitrite was not detected in fruits vegetables and rootcrops but the nitrate contents were abundant and the highest in squash(average, 86.2 mg/kg) and radish(average, 297.5 mg/kg), respectively. In spice vegetables, mate contents were from 0 to 29.8 mg/kg, but not detected in garlic. In welsh onion, its nitrite were higher in small type than large type, while nitrate contents were higher 3 times in the latter. Nitrate contents of fruits were lower in apple(average, 0.5 mg/kg) and higher in plum(average, 76.6 mg/kg) than other samples.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.32-37
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• 1991

Cell and intercelullar space enlarged during maturation. The cell of soft persimmon was separated from each other. The degradation of middle lamella exhibited in mature persimmon and small vesicle appeared in cytoplasm of turning and mature persimmon. The middle lamella and cell wall were degraded during softening.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.817-826
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• 2005

Recently it has been reported that vitamin A and retinol binding proteins (RBPs) in blood and urine were changed in the condition of diabetes mellitus or hyperlipidemia. Fruits and vegetables are recommended to consume for the people suffered from these chronic degenerative diseases. The main components of fruits and vegetables are dietary fibers, for example cellulose and pectin, of which function to affect the absorption and excretion of dietary fat and fat-soluble substances. This study was conducted to investigate the effect of dietary fibers on RBPs mRNA expression in liver, small intestine and serum of rat fed high fat diet during 4 weeks. Sprague-Dawley rats, weighing 121g on average, were divided into four groups; (Control; $17\%$ fat & cellulose supplement diet, HF0: $25\%$ fat & fiber free diet, B:.Uc: $25\%$ fat & cellulose supplement diet and HF0: $25\%$ fat & pectin supplement diet) . The rats fed high fat diet groups (HF0, HFC, HFP) tended to consume the food less than the control group, but FER of HF0 groups was significantly higher than the control (p < 0.05) . The weight of adrenal gland in high fat diet groups (HF0, HFC, HFP) was significantly less than the control. Total lipid in feces daily excreted and in liver did not show any significant differences among the groups. Total cholesterol in HFP group was significantly different from that of HFC group. Serum total cholesterol and triglyceride in other group tended to lower than other groups and HDL cholesterol higher. Consequently, AI (atherogenic index) was the lowest in HFP group. Vit A contents in feces daily excreted tended to lower in high fat diet groups (HF0, HFP) compared to the control group. That content in adrenal gland was the lowest in HF0 group, but not in liver. In HFP group were down-regulated cRBPI mRNA in liver and cRBPII mRNA in small intestine and up-regulated RBP and transthyretin expression in serum compared to the other groups. In conclusion, dietary fibers, especially pectin, in high fat diet might down-regulate the expression of CRBP I, CRBP II mRNA in liver and small intestine, but increase the secretion of RBP into serum and therefore inhance the bioavailability of Vit A through the body. (Korean J Nutrition 38(10): 817$\sim$826,2005)