• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.225-231
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• 2010

Extremely low values of the daily minimum temperature occurred in January 2010, ranging from -18 to $-29^{\circ}C$ at various locations growing peach trees in the Gangwon province. Due to the extreme cold temperature during the winter dormancy period of peach trees, the growth of the peach trees was damaged and the damaged areas increased as the extent of 17 to 144 ha. In order to provide information on mitigation measure of the cold temperature on the peach trees in the Gangwon province, we assessed the distribution of the damaged areas of growing the peach trees in 2010 and compared it with freezing risk estimated from the dormancy depth of the peach trees and the daily minimum temperature. The dormancy depth of 'Changhowon Hwando (Prunus persica (L.) Batsch)' ranged from -62 to -90 and the freezing risk was greater than 51%. The relationship between the freezing risk and the actual damaged area ratio showed reasonable agreement ($r^2$ of 0.5 with p < 0.01). The results imply that the estimates of the freezing risk based on the dormancy depth can be used as a mitigation measure to identify susceptible peach growing areas to freezing damage injury.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.5
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• pp.52-62
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• 2004

This research is basic research about 「the afforestation project of the Shilla Dynasty's capital forest」 which is controlled by the research institute of forest and environment of Kyungbuk province. The results of the investigation about target places and selection of major species of trees is as follows. 1. In the Shilla Dynasty's times, the peach tree was the indicator of unusual changes in weather, and was also the symbol of unsurpassed beauty. Peach trees were so prevalent that people called the forest peach-hill or peach-forest. Therefore, the main tree of Shilla Dynasty's capital forest would have to be a peach tree. 2. From several records, pine and bamboo were planted or grown together. The pattern of planting trees like this case is also historic, so should be utilized positively. 3. In order to afforest the capital forest, the bamboos have to be planted on Nam-mountain in Kyung-ju, and maple trees have to be planted on Kumgang mountain. 4. There were many big trees during the Shilla Dynasty, and the name of one of the Six Main Villages was 'Big Tree Village'. Therefore, big and long-lived trees have to be planted also. 5. The willow tree has to be considered for afforesting the capital forest even though the willow trees are misunderstood to cause allergies. They are traditional landscape architecture trees. In the traditional literature, the willow tree stands for good news. 6. Japanese cornellian cherry(Cornus officinalis), which is related with old narrative literature in the era of King Kyungmun, has to be planted for the forest, and has to be considered to be an educational tree. 7. Korean Rhododendron, which is related with Madam Suro's story, has to be planted in stone gardens.8. Lotus, Korean pulsatilla, Boxwood, Bombycis Mulberry, and Japanese Apricot have been recorded just one time, but these are also important plants which have to be reflected on afforestation of capital forest project. 9. The forests of Shilla on the old records exist in 17 places. The afforestation project has to be undertaken at these places. 10. The people of Shilla deified the forest and trees, which were the places where ancestral rites had been performed. For example, Gyerim, Sinyurim, and Wanggasu were the sacred forests of the capital forest.

• Korean Journal of Weed Science
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• v.7 no.3
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• pp.337-347
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• 1987

Spary and vapor drift injuries of apple, pear, and peach seedling caused by soil-applied oxyfluorfen were studied in a greenhouse. Bud bursting rate of all fruit trees was reduced by both spray and vapor drifts of oxyfluorfen, but reduction in bud bursting rate of pear and peach was greater than that of apple trees. Reduction in the number of leaves per shoot of apple and peach was greater than that of pear trees. Leaf injury of pear was most severe and occurred earliest, but leaves of peach were least injured, Leaf injuries of pear and apple were caused by both spray and vapor drifts, but leaves of peach was injured largely by vapor drift. Reduction in shoot growth of and pear was greater than that of peach trees. Shoot growth of pear was more rapidly retared compared with apple trees. In the field, oxyfluorfen delayed the time of bud bursting in young apple trees. Oxyfluorfen applied between initiation and completion of bud bursting delayed bud bursting more than earlier application although ultimate number of bursted buds was similar to control. The number of leaves per shoot and total length of shoots were lower than control until 40 days after application of oxyfluorfen, and then were similar to control because of vigorous growth after May.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.737-754
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• 2019

Peaches have soft tissues compared to other fruits and are vulnerable to softness, wounds, and loss of marketability due to the weak fruit hardness after harvest. It is necessary to develop a technology to improve the shelf-life of the fruit to expand the distribution of peaches. Calcium compounds and chitosan have an important role in improving the shelf-life of fruit by maintaining the hardness and reducing the respiration rate in peach fruits. In this study, to select useful compounds to improve the shelf-life of peaches, calcium citrate, calcium chloride, calcium nitrate, GH-Ca, OS-Ca, chitosan, and chitosan dissolved in calcium chloride were sprayed onto peach trees. The characteristics of the harvested fruits were investigated after the 'Kumhong' and 'Madoka' peach tree treatments. The hardness of the fruit was kept the highest with the combined treatment and remained high with the calcium citrate, chitosan and calcium nitrate treatments. Ethylene production and respiration were effectively inhibited by the GH-Ca and chitosan treatments. There was no significant difference in soluble solids content and acidity among the fruits treated with the chemicals. The coloration of the fruit skin was not delayed by the calcium and chitosan chemical treatments. Calcium compounds were increased in the fruits and leaves of the peach trees treated with the chemicals compared to the untreated ones. These results suggest that the calcium treatment extended the shelf-life by increasing the calcium content in the leaves and fruits of the peach trees.

• Research in Plant Disease
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• v.7 no.1
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• pp.37-41
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• 2001

This experiment was carried out to investigate the prevention of bacterial shot hole by Bordeaux mixture when it was sprayed on peach trees after harvest. bordeaux mixture was sprayed on \`Mibaeko\` peach trees 1 to 3 times after mid September, and the occurrence of bacterial shot hole was examined in the next year. Bacterial shot hole in leaves appeared from mid May and thereafter increased gradually. The more times was sprayed Bordeaux mixture, the less peaches were diseased with bacterial shot hole. At the beginning of August, the peach harvest time, the disease incidence of the untreated control plot was 27.4 to 38.1%, while the disease incidence was 9.7 to 31.8% when Bordeaux mixture was sprayed. The control value ranged from 16.5 to 64.6%. Occurrence of the fruit disease was similar to that of the leaf disease. Incidence of the fruit disease in the untreated control was 17.2 to 21.6%, but incase of the chemical treatment, it was 5.0 to 12.2 %, showing 41.9 to 70.9% of the control value. Chemical injury on peach leaves were not found in the 4-12 and 408 types, but occurred in some degrees in the 6-6 type of Bordeaux mixture.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.213-220
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• 2009

In order to predict the risk of freeze injury for 'Changhowon Hwangdo' peach trees, we used the dormancy depth (i.e., the daily chill unit accumulation during the overwintering period) as a proxy for the short-term, physiological tolerance to freezing temperatures. A Chill-days model was employed and its parameters such as base temperature and chilling requirement were optimized for peach trees based on the 12 observational experiments during the 2008-2009 winter. The model predicted the flowering dates much closer to the observations than other models without considering dormancy depth, showing the strength of employing dormancy depth into consideration. To derive empirical equations for calculating the probabilistic freeze risk, the dormancy depth was then combined with the browning ratio and the budburst ratio of frozen peach fruit branches. Given the exact date and the predicted minimum temperature, the equations calculate the probability of freeze damages such as a failure in budburst or tissue browning. This method of employing dormancy depth in addition to freezing temperature would be useful in locating in advance the risky areas of freezing injury for peach trees production under the projected climate change.

• Research in Plant Disease
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• v.18 no.4
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• pp.391-395
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• 2012

To investigate the occurrence of viruses in peach, leaf samples were collected from peach trees in commercial orchard of six areas in Korea. Reverse transcription polymerase chain reaction (RT-PCR) was used to identify the presence of the following stone fruit viruses: Apple chlorotic leaf spot virus (ACLSV), Apple mosaic virus (ApMV), Prune dwarf virus (PDV), Prunus necrotic ringspot virus (PNRSV) and Plum pox virus (PPV). About 65.0% of the 515 samples were infected with ACLSV and PNRSV. Virus-like symptoms showing mosaic on leaves was observed in ACLSV infected peach trees. However, PNRSV infected peach trees showed no symptoms. These viral DNAs by sequence analysis were confirmed 4 ACLSV isolates and 3 PNRSV isolates. The Korean peach isolates of ACLSV and PNRSV showed 70-99% and 88-99% amino acid sequence identities, respectively, with those reported previously and their amino acid sequence identities with each other were approximately 95% and 88%, respectively. Phylogenetic analysis indicated that the Korean ACLSV isolates belong to the A group of ACLSV. The Korean PNRSV isolates reported in this study were grouped into I (PV32), II (PV96) and III (PE5) groups.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.367-370
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• 1998

Monilina fructicola, the brown rot fungus of stone fruits, was isolated from overwintering mummies and peduncles on peach trees from February to March, 1998. The resistant population of these isolates to benzimidazole (benomyl, carbendazim and thiophanate-methyl) and dicarboximide (iprodione, vinclozolin and procymidone) was examined. Among 417 isolates, the incidence of isolates resistant to benomyl, carbendazim, and thiophanate-methyl were 45 (10.8%), 47 (11.3%), and 46 (11.0%), respectively. Forty two (10.0%) isolates showed cross-resistance to benzimidazole fungicides. On the other hand, the resistant isolates against iprodione, vinclozolin and procymidone were 186 (44.6%), 1 (0.2%) and 150 (36.0%), respectively. Among the isolates, 116 (27.8%) showed cross-resistance to iprodione and procymidone. Moreover, 27 (6.5%) of 417 isolates showed double-resistance to both benzimidazole (benomyl) and dicarboximide (iprodione).

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.356-364
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• 2009

In 2006 and 2007, there was a big outbreak of the Ussur Brown Katydid, Paratlanticus ussurriensis in the central part of Korea attacking some orchard trees. Until 2000, the katydid had not been regarded as an agricultural pest because they were distributed widely in Korea with low population density and their habitats were confined mainly to hillsides of forested areas. The fact that katydid attacked orchard trees with a higher population density seemed to be related to a change in feeding environment. And the shift of their habitats from oak woodlands to commercial orchards was thought to be related to the nutritional contents of their feed. In an attempt to understand these relationships, we conducted an ecological study of the affected areas. When the katydids changed their habitats in early May of 2008 and 2009, they shifted their host plants from oak trees to peach trees. The habitat shift was closely related to the nitrogen (N) content of the host plant leaves. When katydid moved to the hillside adjacent to orchard farm, N content of oak tree leaves decreased dramatically from 5.3% to 2.2%. At that time N content of peach tree leaves were higher than the 2.2% of oak leaves, showing 3.5~5.0%. This range of N content of peach tree leaves has been consistent until late June. And feed preference analysis carried out in the laboratory showed that katydid prefered peach tree leaves to peach fruit to oak tree leaves.

• Plant Disease and Agriculture
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• v.5 no.2
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• pp.115-118
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• 1999

A new bacterial disease was found on trees of peach(Prunus persica var. vulgaris Max) at Kumho Kyungbuk in April 1999. The disease usually occured on over wintered buds branchs and stems of the Cheon-Hong cultivar. The buds died without sprouting and the branches showed entire wilting Droplets of bacterial ooze was occasionally running down the surface of diseased plants under moist condition. Artificial needle prick inoculation with isolates obtained from branchs of naturally infected plants produced symptoms similar to those occuring under natural condition. On the basis of bacteriological characteristics and pathogenicity on the host plant of the organism the causal bacterium was identified as Xanthomonas arboricora pv. pruni and this disease was proposed to name "Bacterial branch blight of the peach tree"