• Research in Plant Disease
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• v.23 no.1
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• pp.49-55
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• 2017

The previous study showed that die-back of apple trees caused by soil-borne diseases was significantly high in the apple orchards in Chungbuk province. The correlation between dieback ratio and cultivation environment in apple orchards infected by soil-borne diseases was investigated in this study. The dieback ratio of five orchards diseased by violet root rot and five places infected by white root rot showed significantly positive correlation with Ca content and available $P_2O_5$ content in soil, respectively. Whereas, the dieback ratio of fourteen orchards diseased by Phytophthora root rot was not significant. Subgrouping of cultivation environment analysis showed that the slope degree of orchard and the number of fruit setting also affected the dieback ratio caused by violet root rot and Ca content in soil also affected the dieback ratio caused by white root rot. It showed that the slope degree, soil texture, Mg and Ca content affected the dieback ratio caused by Phytophthora root rot. These results can be applied to reduce die-back ratio by the modification cultivation environment for each soil-borne disease.

• Research in Plant Disease
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• v.23 no.1
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• pp.75-81
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• 2017

In May 2016, 24 peach samples showing abnormal and virus like symptoms were collected in one of major peach producing area, Yeongcheon-si, Gyeongsangbuk-do, Korea. We performed RT-PCR diagnosis for confirmation of viral infection. The diagnostic targets are 17 species of viruses and viroids that quarantine and high risk pathogens when it occur. As a results, seven species of viruses and viroids, including an unreported (Apricot pseudo-chlorotic leaf spot virus, APCLSV) and a quarantine (Peach latent mosaic viroid, PLMVd) species in Korea, were detected. For the sequence analysis of unreported virus, APCLSV, the sequence of coat protein gene were amplified and cloned. The sequence showed 97% nucleotide identity with other APCLSV isolates and compared with other seven species of reported Trichoviruses. This virus was classified as APCLSV based on the sequence and phylogenetic analysis. This isolate was named Yeongcheon. As patterns of APCLSV occurrence, all samples that APCLSV detected were co-infected with Apple chlorotic leaf spot virus (ACLSV). As properties of ACLSV, APCLSV has high possibility of wide spread disease in fruit tree farms in Korea. Therefore, it is necessary to do related researches, such as infection route and influence of disease in commercial orchards.

• Research in Plant Disease
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• v.22 no.3
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• pp.158-167
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• 2016

A pathogen that causes a new disease on green pumpkin in the nursery and the field was characterized and identified. Symptoms of the disease on green pumpkin were water soaking lesions and spots with strong yellow halo on leaf, brown lesion on flower, and yellow spot on fruit. The bacterial isolates from the leaf spot were pathogenic on the 8 curcubitaceae crop plants, green pumpkin, figleaf gourd, wax gourd, young pumpkin, zucchini, cucumber, melon, and oriental melon, whereas they did not cause the disease on sweet pumpkin and watermelon. They were Gram-negative, rod shape with polar flagella, fluorescent on King's B agar and LOPAT group 1a by LOPAT test. Their Biolog substrate utilization patterns were similar to Pseudomonas syringae pv. syringae's in Biolog database. Phylogenetic trees with 16S rRNA gene sequences and multilocus sequence typing (MLST) with nucleotide sequences of 4 housekeeping genes, gapA, gltA, gyrB, rpoD and those of P. syringae complex strains in the Plant Associated and Environmental Microbes Database (PAMDB) showed that the green pumpkin isolates formed in the same clade with P. syringae pv. syringae strains. The clade in MLST tree was in the genomospecies 1 group. The phenotypic and genotypic characteristics suggested that the isolates from green pumpkin lesion were P. syringae pv. syringae.

• Journal of the Korean association of regional geographers
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• v.2 no.2
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• pp.197-204
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• 1996

We attempt to classifing method of micro-landform on the alluvial plain, such as natural-levee, backmarsh and alluvial fan, using false color composite of Landsat Thematic Mapper image. The study area is Kumho River Basin on the southeastern part of Korea peninsula. The most effective image for micro-landform classification is the false color composite of band 2, 3 and 4 with blue, green and red filtering. The most favorable time is the middle third of November, because of the density differentiation of green vegetation in most great. In this time the paddy field on the back-marsh is bare by rice harvesting. But on the natural levee the green vegetation, such as vegetables and lower herbs under fruit tree, remain relatively more. On the alluvial fan, the green vegetation condition is medium. For the verification of the micro-landform classification, we employed the field survey and grain size analysis of the deposition of each micro-landform on the sample area. It is clarified that the classification method of micro-landform on the alluvial plain using the Landsat TM image is relatively useful.

• Journal of the Korean Society of Food Culture
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• v.5 no.3
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• pp.349-359
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• 1990

This study was carried out to understand and analyze the cooking and processing methods presented in CHE MIN YO SUL, Chinese books of husbandary was written in sixth century. This book was composed of two parts-part I is Agricultural production and part II is product-Utilization. Especially, wines and yeast(NU RUK) written in part II were studied at this study paper. Most of yeast was made of barley and wheat. These materials had been prepared as raw, steamed, and roasted state by proper ratio with kinds of yeast and then fermented as dough state. Occasionally, various kinds of soup made from cocklebur, leaves of mulberry tree, wormwood etc. put into yeast dough. Yeast doughs were shaped round and square with or without hole in the center, made in July of the lunar calendar and fermented for 3 or 4 weeks. There were 43 kinds of wines in this book. Most of them were made of all kinds of cereals grown at that time-rice, waxy rice, millet, waxy millet etc. These cereals had been steaming or cooking gruel with grain or powder state and then fermented with yeast. These wines were prepared by single or double brewing methods and the kinds of double brewing wines were more than single brewing wines by two times. There were none of wines made from fruit and distilled wines. Generally, single brewing wines were not made in Apr., Nov., Dec., of the lunar calendar and double brewing wines were not made in Aug., Oct., Nov., of the lunar calendar. And ripenning periods of wine brewing were various, from 1 day to 7 months for single brewing, from 2 days to 8 months for double brewing.

• Korean journal of food and cookery science
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• v.24 no.3
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• pp.312-324
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• 2008

In this study, we investigated the names and various types of "kwa-jung" along with their recipes and ingredients occurring in Korean cookbooks published before the 17th century. The kwa-jungs were classified into 7 groups including Yoomilkwa, Yookwa, Dasik, Junkwa, Kwapyun, Yutganjung and Dang. A total of 72 kinds of kwa-jung were found. 26 kinds of Yoomilkwa, 18 kinds of Yookwa, 7 kinds of Dasik, 10 kinds of Junkwa, 1 kind of Kwapyun, 3 kinds of Yutganjung and 8 kinds of Dang. Among the types of Yoomilkwa, Yackwa was recognized as the best food according to the references. Also the cooking methods for items had a tendency to become simpler as society became modernized. Original and rare Ingredients were often substituted with other items that could be found more easily where people lived As recorded, the Yookwa group included kangyung, sanja, and bingsakwa. And as society became modernized, people tended to buy Yookwa in the store rather than making it at home due to its complicated and often difficult cooking process. The Dasik items were a kneaded mixture of flour, or the flour of chestnuts, with honey. These were formed into various patterns like birds, animals, butterflies, tree leaves and flowers, or as ki-wha by using printing cooking utensils Honey was used as a sweetener and as a combining material. The Junkwa consisted of roots or fruits that could be easily obtained these cooked or raw foodstuffs were then mixed with sugar and simmered. The Kwapyun used sour fruit juices as a main ingredient. These were then combined with sugar and simmered and allowed to harden. Then they were cut into square shapes after cooling. Yutkangjung was a mixture of yut, chochung, honey or syrup and pine nuts. which was combined over low heat. After mixing and stirring it was cut into square shapes. Finally, the Yut was typically cooked with grains and powdered malt and stirred until thickened.

• Journal of Korean Society of Forest Science
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• v.85 no.2
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• pp.309-315
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• 1996

Selective breeding and hybridization were attempted to improve shiitake(Lentinus edodes) strains for bed-log cultivation, and the results obtained are as follows. 1. Thirty five strains collected in Korea and abroad were cultivated for one generation(five years) and fruit body yields were estimated by the amounts produced from $1m^3$ of oak tree(Quercus mongolica) logs. Thus, three high-temperature type strains including FRI 177 showing productivity of $139kg/m^3log$, two mid-temperature type strains including FRI 188 of $120kg/m^3log$, and seven low-temperature type strains including FRI 187 of $96kg/m^3log$ were selected as superior strains. 2. Twelve hybrid strains confirmed as independent strains through indoor-test with hybrid strains made by Di-mon mating method were cultivated for five years(one generation). Among them, FRI 182 and FRI 184 were turned out to be superior strains. FRI 182 of high-temperature type showed the yield of 108kg per $1m^3logs$ and FRI 184 of low-temperature type produced $103kg/m^3log$. 3. There were no significant differences in productivity among high-, mid- and low-temperature types, but some differences appeared among strain groups. The correlation was not shown in productivities between bed-log and sawdust cultivations.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.184-192
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• 2016

This study was carried out to investigate the effect of temperature ($15{\sim}40^{\circ}C$) and the spraying plant growth regulators ($GA_{4+7}+BA$ and prohexadione-calcium) during full blooming on pollen germination and pollen tube growth of the commercial apple cultivars ('Fuji' and 'Tsugaru') and apple cultivars bred in Korea ('Chukwang', 'Gamhong', 'Hongan', 'Honggeum', 'Hongro', 'Hwahong', 'Hongso', 'Summer dream' and 'Sunhong'). Pollen germination and pollen tube growth were increased with increasing temperature from 15 to $25^{\circ}C$, but high temperature over $30^{\circ}C$ inhibit those. The apple cultivar bred in Korea that shows the highest value on pollen germination and pollen tube growth at over $30^{\circ}C$ was 'Sunhong'. The spraying $GA_{4+7}+BA$ increased pollen germination and pollen tube growth than control, but that effect was not show at $40^{\circ}C$. The spraying prohexadione-calcium was not affect to pollen germination and pollen tube growth. In conclusion, if the air temperature during full bloom of apple tree rises about $30{\sim}35^{\circ}C$, the spraying $GA_{4+7}+BA$ after artificial pollination will be good to increasing fruit set.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.348-356
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• 2016

Carbon dioxide ($CO_2$) gases concentration in atmosphere has been growing since preindustrial times. By sequestering a large amount of atmospheric carbon (C), terrestrial ecosystems are thought to offer a mitigation strategy for reducing global warming. Woody agro-ecosystems such as fruit tree are among the least quantified and most uncertain elements in the terrestrial carbon cycle. $CO_2$ and energy fluxes were measured by the eddy covariance method on a 15-year old apple orchard of South Korea in 2006. Environmental parameters (net radiation, precipitation, etc.) were measured along with fluxes. The results showed that during late June, the ability to sequestrate C was significant at an apple orchard ecosystem and it reached on the peak of $-6.5g\;C\;m^{-2}\;d^{-1}$. We found that in the apple orchard, the daily average of net ecosystem exchange of $CO_2$ (NEE) and cumulative NEE on a yearly basis were $-1.1g\;C\;m^{-2}$ and $-396.9g\;C\;m^{-2}$, respectively. These results reveal that there is high carbon sequestration in the apple orchard of South Korea, which is the same magnitude with repect to that of a natural forested ecosystem of the same biome rank (temperate-humid deciduous forest).

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.378-384
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• 2018

Chinese jujube (Ziziphus jujuba Mill.), a member of family Rhamnaceae, is an economically important species. It has high nutritional value in fruits, and its medicinal properties have led to extensive use in traditional oriental medicine. In this study, we investigated the genetic characteristics of 270 jujube germplasms collected from the six major jujube fruit production areas in Korea including Boeun and Gyeongsan, in order to understand the current situation on cultivated varieties of domestic jujube and to obtain useful data for selection of superior germplasms and establishing their breeding plans. The results of ISSR marker analysis revealed that the Shannon's information index of the 270 germplasms was 0.107 and the genetic similarity was as high as 0.935 showing the dominance of a specific cultivar or germplasm, and almost 67% (180) of them were identified at the same genotype with 'Bokjo'. The domestic commercial jujube populations could be characterized by very low genetic diversity and thus may be vulnerable to external disturbances. In addition, it seems that most of the jujube fruits in domestic market were largely produced through parthenocarpy.