• The Plant Pathology Journal
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• v.24 no.3
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• pp.269-278
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• 2008

Ripe rot was frequently observed on fruits, leaves and stems of grape growing in eight locations in Korea from 2004 to 2006. All 30 isolates of Colletotrichum sp. were obtained from lesions of the ripe rot on grape plants. Out of the isolates, 19 isolates were identified as Colletotrichum acutatum and the others as Colletotrichum gloeosporioides based on morphological and cultural characteristics. Inter and intra specific variations of the Colletotrichum spp. isolates were investigated using RAPD and sequences of rDNA ITS and $\beta$-tubulin-2. Isolates of C. acutatum and C. gloeosporioides were distinctly differentiated by molecular analyses. Phylogenetic trees of ITS and$\beta$-tubulin-2 showed that Korean isolates of C. acutatum were clustered into groups A2 and A3 among the eight global groups. A2 included non-chromogenic isolates and A3 chromogenic ones. Both C. acutatum and C. gloeosporioides isolates were tested for pathogenicity to grape leaves. All isolates tested induced lesions on the leaves of grape by artificial inoculation. There was no difference in pathogenicity between C. acutatum and C. gloeosporioides isolates. This is the first report that C. acutatum except C. gloeosporioides causes grape ripe rot in Korea.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.380-387
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• 2013

The objective of this study is to investigate the effect of elevated $CO_2$ and temperature on the phenology and reproductive ecological characteristics of Bupleurum latissimum. We measured characteristics of 4-year-old B. latissimum grown under control (ambient $CO_2$+ambient temperature, 340~370 ppm) and treatment (elevated $CO_2$+elevated temperature, 690~770 ppm) conditions in a glass house. The period of flowering, fruit appearance and fruit maturing was earlier by 4, 1, 2 days, respectively, under elevated $CO_2$ and temperature. The comparative weight of a single ripe fruit, all ripe fruits and total ripe and unripe fruits was higher per control than treated plants. However the other characteristics, such as no. of peduncle, matured fruits, total fruits per plant and fruit setting rate per plant of B. latissimum were not significantly affected by elevated $CO_2$ and temperature. The germination rate of B. latissimum was higher in control than in treatment plants. These results showed that the phenology of B. latissimuin might be well suited to an earlier growing season, and the response of reproductive characteristics of B. latissimuin is negatively influenced by global warming.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.405-411
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• 2011

In this study, we evaluated the changes of fruit quality indices during fruit development and ripening in Korean new pear cultivar 'Wonhwang' and 'Whasan' to determine appropriate harvest time and to enhance the marketability. The fruit of each cultivar harvested from 100 days after full bloom (DAFB) to 135 and 150 DAFB in 'Wonhwang' and 'Whasan', respectively. The fruit growth of both cultivars showed a typical single sigmoidal pattern. Flesh firmness of two cultivars decreased continuously with fruit development and ripening, reaching a final level of about 2.6 kgF at harvest stage. The starch content of fruit sap was much higher in the fruits of early development stage than the later stage of fruit ripening. In 'Wonhwang' pears, the starch level decreased coincide with fruit ripening (130 DAFB), while that of 'Whasan' decreased from very early stage of fruit development (120 DAFB), 30 days before full ripe. 'Whasan' pear showed much lower acidity level of about 0.13% during fruit development and ripening period compared with that of 'Wonhwang'. Therefore, the ratio of soluble solids to total acidity (TSS/acid) increased gradually with fruit development and ripening, reaching a final level of 80 and 98 in 'Wonhwang' and 'Whasan', respectively. There were no climateric rise of fruit respiration during fruit ripening periods in two oriental pear cultivar. The changes of skin color difference including hunter vale $a^*$ which means loss of green color occurred only after onset of ripening in two cultivars.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.157-163
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• 1985

Various cell wall polysaccharides and related enzyme activities in hot pepper fruit were determined at different stages of maturity. The uronic acid content of cell walls decreased between immature green and turning stage fruit and then increased by red ripe stage. In contrast, cellulose content of cell walls changed only a little during ripening. Total neutal sugar content of cell wall material decreased 50% and galactose content of the walls decreased about 80% by the turning stage. Polygalacturonase and ${\beta}-galactosidase$ activities, as well as total hemicellulose from isolated cell walls of ripening hot pepper fruit were studied using gel filtration chromatography. Polygalacturonase activity was not detectable but 5 isozymes of ${\beta}-galactosidase$ were resolved. The activities of the enzymes were relatively high and gel filtration showed that they differed in molecular weight. Hemicellulose content decreased during ripening and softening. The molecular weight profiles shifted from high molecular weight to low molecular weight polymers during ripening. The changes in cell walls that may be associated with fruit softening involve the alteration of hemicellulose prior to the degradation of wall-bound uronic acid. It is suggested that the decrease in cell wall galactose involved changes in turnover of new cell wall components.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.259-264
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• 1995

To elucidate the effect on the quality of products, various components of ume fruit(Prunus mume)flesh of six species during development and maturation. The weigh and the rate of flesh of ume fruit was increased until maturation, except of small ume. The relative hardness of ume fruit flesh was 2.5~3.9 Kg and decreased at full ripe. The major organic acids of ume fruit flesh was citric acid and malic acid. Citric acid became increased, but malic acid was decreased during maturation and total content of that was increased during maturation Free sugars determined from the ume fruit flesh were fructose, glucose, sucrose. Ascorbic acid content was $0.6\sim2mg%$ in the ume fruit flesh. The contents of K and Ca were abundant minerals in ume fruit flesh.

• The Korean Journal of Ecology
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• v.23 no.2
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• pp.113-116
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• 2000

Different phenological patterns of leaf and fruit fall among native and non-native riparian species provide a spatially and temporally heterogeneous series of alternative food resources for detritivores. Relatively little is known about qualitative differences among these different riparian species. Rates of litter inputs, decomposition, and retention for different sources of riparian litter require long-term documentation. Species of freshwater shrimps, crabs. insects. and gastropods are known to consume a wide range of litter inputs but how these dynamic food webs function under changing climatic and land-use conditions is unknown, especially in tropical streams. On-going studies in the Luquillo Experimental Forest. Puerto Rico provide an example of how inputs of fronds and fruits from palms (Prestoea montana) serve as important foods and microhabitat for species of freshwater crabs and shrimp. Native riparian species such as Prestoea montana are commonly distributed in the Luquillo Mountains especially along steep slopes and stream banks. After tropical storms with high winds, the large fronds from these native riparian trees provide important inputs of leaf litter to the stream food web. In some streams, the input of ripe fruit from non-native trees such as Java plum (Syzigium jambos) also provides a major source of detrital food resources, especially during periods when fruit fall from native species of palms may be limited.

• 한국약용작물학회:학술대회논문집
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• 2008.05a
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• pp.202-203
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• 2008

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.40-60
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• 2003

Fruit ripening represents a genetically synchronized system that involves developmental process unique to plant species, The phenomenon of ripening includes changes in color, texture, respiration rate, flavor, and aroma. Ripe fruits generally exhibit increased susceptibility to pathogen infection. However, fruits as a reproductive organ have their own protection mechanism against pathogens to maintain their integrity during seed maturation. In several nonclimacteric fruits, such as cherry, grape, and pepper, that do not have an ethylene burst during ripening, resistance against phytopathogens increases during ripening. Colletotrichum gloeosporioides is a causal agent of anthracnose disease in pepper plants (Capsicum annuum). We have established that C. gloeosporioides has susceptible and resistant interactions with pepper fruits during pre- and post-ripening stages, respectively. And we have interested in looking for a molecular mechanism that would explain the fungal resistance during ripening of nonclimacteric pepper fruit. In this presentation, a molecular characterization of the pepper esterase gene (PepEST) that is highly expressed in the resistant response will be demonstrated as an example of development and industrial applications of versatile-usable genes of plant.

• The Plant Pathology Journal
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• v.29 no.1
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• pp.77-86
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• 2013

Anthracnose development by Colletotrichum musae was observed to be significantly less in the fruits of the banana cultivar 'Embul' (Mysore, AAB) infected with Phyllosticta musarum than in fruits without such infections. Anthracnose disease originates from quiescent C. musae infections in the immature fruit. P. musarum incites minute, scattered spots, referred to as freckles, in the superficial tissues of immature banana peel which do not expand during maturation or ripening. P. musarum does not appear to have a direct suppressive effect on C. musae as conidia of C. musae germinate on both freckled and non-freckled fruit forming quiescent infections. Our investigations have shown that P. musarum infection induced several defence responses in fruit including the accumulation of five phytoalexins, upregulation of chitinase and ${\beta}$-1,3-glucanase, phenylalanine ammonia lyase (PAL) activity and cell wall lignification. $^1H$ and $^{13}C$ NMR spectral data of one purified phytoalexin compared closely with 4'-hydroxyanigorufone. Some of the P. musarum-induced defences that retained during ripening, restrict C. musae development at the ripe stage. This paper examines the potential of P. musarum-induced defences, in the control of anthracnose, the most destructive postharvest disease in banana.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.265-274
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• 2014

Physiological characteristics of two Korean golden kiwifruit cultivars, 'Halla Gold' and 'Haehyang', were compared to determine the storage potential of fruit. The soluble solid levels of the fruit were 8.9 and 6.9 oBrix in 'Halla Gold' and 'Haehyang' at harvest, respectively but increased up to 15.4 in 'Halla Gold' and 17.5 oBrix in 'Haehyang' after 2 months of storage. Major sugars were fructose and glucose, and sucrose content was relatively low regardless of cultivar. The edible quality of 'Haehyang' was better than 'Halla Gold' because of higher amount of sugars. Firmness of the fruits gradually decreased as the increase of storage period in 'Halla Gold' in both flesh and core tissue. Th firmness loss of 'Haehyang' fruit was faster in the first 2 months and then became slow. After 75 days of storage, the firmness of 'Haehyang' fruit was only 5.2% at harvest. Core tissue was soften enough to eat at ripe stage. Wall modifying enzyme activities including xylanase, ${\alpha}$-L-arabinofuranosi-dase and ${\beta}$-galactosidase were consistently higher in 'Haehyang' and the activity of pectate lyase was more increased than 'Halla Gold' after 2 months of storage. Respiration rate of 'Haehyang' was higher than 'Halla Gold' and further increased after 2 months of storage. Weight loss was much higher in 'Haehyang' which showed higher rate of the firmness loss. The storage potential of golden kiwifruit was estimated to be about 2 months for 'Haehyang' and 3 months for 'Halla Gold' when determined on the basis of the fruit firmness.