• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.255-261
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• 2016

The present study was conducted to characterize physiological responses of aerial part according to soil water stresses in 'Mihong' peach trees. Discolorations, wilting and falling of leaves were observed in chronological order as response for waterlogging and no irrigation and the phenomena started from basal to end of shoots. Shoot growth in elongation and thickness decreased and fallen leaves were severe in waterlogged trees. Function of water uptake by roots and photosynthesis and leaf respiration decreased by waterlogging. Leaf chlorophyll contents decreased in both treatments. In waterlogging treatment, decrease of chlorophyll was observed in normal leaves with waterlogging using light microscopy. Starch content was lower in both treatment and carbohydrate content was lower in root with waterlogging. These results demonstrated that waterlogging weakened the function of soil water uptake and movement and decreased photosynthesis and fallen leaves. Finally the peach trees would wither or suffer low temperature damage through the shortage of reserve accumulations. We suggested that waterlogging damage in peach trees could be reduced to take notice of irrigation and install drainage facility to improve soil condition.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.291-296
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• 2017

This study was conducted to evaluate the influence of early defoliation on photosynthesis and carbohydrate reserves when the source leaves of 'Fuji'/M9 apple (Malus domestica Borkh.) trees were removed during the growing period. Bud regrowth rates of 80%, 50% defoliation and non-defoliation treatments were significantly different 82.7%, 45.9% and 2.1% respectively at 30 days after treatment. In all treatments, sucrose and starch concentrations in remaining leaves decreased non-significantly during the 14-day period. No significant changes were observed for total soluble carbohydrates in non-defoliation and 50% defoliation. However, in 80% defoliated treatments, concentrations of sorbitol and total soluble carbohydrates in remaining leaves declined steadily during the 14-day period. It is thought that high sink strength increases the requirements of carbohydrate from remaining leaves more than non-defoliated. The concentrations of starch in the roots tend to decrease non-significantly as percentage of defoliation increased. Photosynthesis of remaining leaves was monitored during the 14-day period after partial defoliation treatments. Net photosynthetic rates (Pn) and stomatal conductance were significantly enhanced in the 80% defoliation. The observed photosynthetic enhancement following partial defoliation may have been due to the enhancement of osmotic potential in leaves. These results were estimated that increasing of photosynthetic rate in the partial defoliation is due to the sink carbohydrate requirements for the current year's secondary growth of buds.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.440-447
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• 2014

For this analysis, canopies of slender-spindle 'Hongro'/M9 apple trees were divided into 4 positions: upper, lower, exterior, and interior parts. The photosynthetic rate was highest in the external part of the upper canopy of the tree, where it was 4.5 times higher than in the internal part of the lower canopy. This difference was closely associated with differences in light penetration based on canopy position. Analysis of leaf growth characteristics showed that the leaves situated in the internal part of the canopy were larger and thinner than those in the external part of the canopy. The difference in leaf thickness was mainly due to thickness of the primary layer of palisade tissues (68.5 and $110.3{\mu}m$ for internal and external leaves, respectively). Fruit weight and quality were closely related to the extent of light penetration. Fruit weight, soluble solid content, and red skin color were higher in the fruits from the external part of the canopy. Thus, fruit maturity was delayed in the internal part of canopy. The fruit skin and wax layer were thicker in fruits from the internal canopy than in those from the external canopy. Therefore, our results indicate a need for improved light penetration in internal parts of the canopy and for split harvesting depending on maturity at different canopy positions.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.512-516
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• 2013

Pear cultivar 'Sinhwa' (Pyrus pyrifolia var. culta Nakai) was originated from a cross between 'Niitaka' and Whasan' with the aims of improving the fruit quality and the traits of cultivation and of early maturing more than 'Whasan' cultivar at Pear Research Station of National Institute of Horticultural & Herbal Science, Rural Development Administration in 1995. 'Sinhwa' was preliminarily selected in 2004 and named in 2009. The tree shows vigorous growth habit and semi-spread characters like 'Niitaka'. Furthermore, it has a sufficient and well upkeep of the flower bud, so it can be more easily cultivated in orchards. In the flower characteristics, flowering time of 'Sinhwa' is $11^{th}$ April like as maternal parent 'Niitaka'. Also 'Sinhwa' has short of pollen grains, so it is need above two pollinizer cultivars. 'Sinhwa' is highly resistant to black leaf spot (Alternaria kikuchiana) and relatively strong to pear scab (Venturia nashicola) in field condition. The optimum harvest time is around Sep. $15^{th}$ in Naju, which is ahead of 'Whasan' about 10 days in the harvest period. The fruit shape is oblate and fruit skin color is yellowish-brown during harvesting time. The average weight of fruit is 627 g, and the soluble solids content is $13.0^{\circ}Brix$. The flesh is very soft and juicy, and renders good eating quality. Shelf life is about 30 days under the room temperature condition.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.206-211
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• 2016

Modified T trellis (MT) and Wakeman trellis (WT) were widely used Korean vineyard because they had an advantage for spur pruning type cultivar such as Campbell Early. In this experiment, we compared labor time and intensity for bunch management between MT and WT trellis systems in 'Campbell Early' grapes. As a result, berry thinning was required 17.3 hours (10a) on the WT trellis but was required 12.3 hours (10a) on the MT trellis. In like manner, bagging was required 10.1 hours (10a) on the WT trellis but was required 8.2 hours (10a) on the MT trellis. On the other hand, labor intensity measured on berry thinning and bagging practices using REBA (Rapid Entire Body Assessment) index, then WT trellis was scored 13.0, but MT trellis was scored 8.6. Meanwhile, MT trellis reduced vigorous growing of internodes length and width on grapevine shoots. Consequently, MT trellis is more convenience trellis for working ergonomically in Korea vineyard.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.327-335
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• 2012

Nutrient uptake of each part of grapevine in the new grapevine cultivars (Jinok, Hongisul) was analyzed for making standard of annual fertilizations at four years. One year grown diploid cultivar 'Jinok' was showed more vigorous growth of root than other cultivar. Annually total nutrient of grapevine was absorbed with the same ratio of three major nutrients (Nitrogen, Phosphate, and Potassium). However about 30% of total absorbed nutrient of 3~4 year grown grapevine was distributed bunches. Potassium was measured as major nutrient in the bunch, accumulated in the peel and flesh (about 1% of D.W.). Magnesium was mainly accumulated in the petiole (about 1% of D.W.). Calcium has accumulated in the leaf (about 0.95% of D.W.), that concentration in this part was similar concentration of nitrogen (about 1.25% of D.W.). Nutrient requirement of four year grown 'Jinok' (N; 55.5 g, P; 7.7 g, K; 42.0 g, Ca; 34.6 g, Mg; 11.1 g) required less fertilizers than 'Campbell Early' (N; 57.4 g, P; 7.9 g, K; 44.4 g, Ca; 37.3 g, Mg; 12.2 g) needed. 'Hongisul' required less fertilizers compared to other grapevine cultivars, but cultural practice system for production of grape should be develop to improve their poor bud burst and fruit set.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.125-134
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• 2017

This study was carried out to examine the effects of soil sulfur mixture on the control apple valsa canker in apple orchard for two years. In organic apple orchard, The recovery percentages of apple valsa canker were compared among control (no treatment), lime sulfur, and soil sulfur in organic orchards. In conventional apple orchards, those of recovery percentages were compared among control, neoasozin, lime sulfur, and soil sulfur. Compared with control, soil sulfur treatments significantly improved the recovery percentages of apple valsa canker infected trees in organic orchard. However, there were no differences between lime sulfur and soil sulfur treatment in organic apple orchard, except BongHyun orchard experiment in 2013. Compared with control fruit qualities, fruit skin red color and fruit firmness were improved in lime sulfur and soil sulfur treatment, respectively. In conventional orchard, apple trees treated with lime sulfur, soil sulfur or neoasozin improved recovery percentages, compared with those of control trees. Soil sulfur treatments recovered 87.5~97.5% of infected 'Fuji'/MM106 apple trees in organic and conventional apple orchards. The trees applied with neoasozin showed significant lower shoot growth than those of soil sulfur treatment in conventional orchard. Soli sulfur treatment improved fruit red color, but did not affected fruit weight, fruit firmness, soluble solids concentrations, and titratable acidity.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.100-102
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• 2016

Ergothioneine is a natural compound with strong antioxidant properties. In this study, the effects of different nitrogen sources including ammonium nitrate, ammonium sulfate, sodium nitrate, and histidine in sawdust media were investigated to enhance ergothioneine contents in Shiitake (Lentinula edodes) fruit bodies. The addition of 0.2% ammonium sulfate in the growth media showed the highest enhancement of ergothioneine content in shiitake fruit bodies which was 1.7-fold higher than the control. On the other hand, histidine, a building block of ergothioneine decreased the concentration of ergothioneine significantly. Our results demonstrate that the cultivation of shiitake in sawdust media with suitable nutrients was effective to enhance its ergothioneine contents.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2007.05a
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• pp.200-203
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• 2007

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.179-183
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• 1999

The volatile components (essential oil) showing antimicrobial activity were extracted from the fruit peel of Zanthoxylum piperitum DC by distillation and separated by thin layer chromatography (TLC). The crude volatile components exhibited antimicrobial activity only at very high concentration. The active fraction obtained by TLC inhibited noticeably the growth of bacteria. The minimum inhibitory concentration (MIC) of the fraction were 150ppm, 300ppm, and 300ppm against Escherichia coli, Staphylococcus aureus, and Salmonella enteritidis, respectively. The components in the active fraction were identified by gas chromatography/mass spectrometry to be geranlyl acetate (60.23%), citronellal(36.01%), citronellol(3.77%), geraniol(0.46%), and cumin ldehyde(0.43%).