• Parasites, Hosts and Diseases
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• v.35 no.3
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• pp.215-218
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• 1997

An unusual over-gravid female of Enterobiw uemiculcris was recovered from a 15-month old child by cello-tape anal swab. The patient resided in Inchon and complained of severe anal itching. The worm measured 7.8 mm in length and 0.5 mm in width, and retained typical morphologic features of E. uemiculnris such as cephalic alas and a sharply pointed posterior end. In this gravid female, peculiarly. the uterus was tremendously distended, and about 99% of the whole body length was completely packed with a great number of eggs. Other internal organs were difficult to observe. This paper describes a peculiar over-gravid female of E. vemiculcyis.

• The Korean Journal of Soil Zoology
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• v.6 no.1_2
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• pp.7-9
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• 2001

Six species of the phytoseiid mites were recorded from the pear field of Naju District in Korea: Amblyseius womersleyi, A. eharai, A. orientalis, A. makuwa, A. bakeri and Proprioseiopsis nemotoi. Of these, A. bakeri and p. nemotoi were previously unrecorded in this field, and genus Proprioseiopsis is recorded for the first time in Korea.

• KOREAN POULTRY JOURNAL
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• s.16
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• pp.104-106
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• 1971

• Korean journal of applied entomology
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• v.41 no.3
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• pp.183-189
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• 2002

Occurrence of scarabs at sweet persimmon (Diospyros kaki var. Fuyu) orchards was investigated by mercury light traps every one week interval in several areas in Gyeongnam province including, Jinju, Sacheon, Sancheong, and Gimhae, from April to September in 2000 and 2001. In addition, damage of persimmon by scarabs was observed every ten days interval at three orchards in Jinju and at one in Gimhae from late May to late October. Although sixteen species of 12 genera were attracted to the traps, species and number of catches were different according to orchards and years. Holotrichia morosa was most dominant in Jinju, Sacheon, and Sancheong. Total number of scarabs attracted to the traps was highest at the orchard surrounded by chestnut orchards in Sancheong. Fruits of sweet persimmon were not damaged by scarabs at the studied orchards. However, leaves and calyxes were slightly damaged by Adoretus tenuimaculatus. Maximum average numbers of the damaged leaves and calyxes throughout the year by A. tenuimaculatus were 0.33 leaves from 10 new shoots and 0.07 calyxes from 15 fruits. Gametis jucunda and Popillia mutans damaged flowers and calyxes. Maximum average numbers of damaged flowers and calyxes by these 2 species were the same as 0.03 from 15 flowers and 15 calyxes, respectively. These levels of damage suggest that the scarabs are not economically injurious to sweet persimmon fruits in Korea.

• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.26-30
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• 2014

Purpose of this study was a development of a sprayer arm auto control system that could be operated according to distance from pear trees for automation of pest control. Auto control system included two parts, hardware and software. First, controller was made with an MCU and relay switches. Two types of ultra-sonic sensors were installed to measure distance from pear trees: one on/off type that detect up to 3 m, and the other continuous type providing 0~5 V output corresponding to distance of 0~3 m. Second, an auto control algorithm was developed to control. Each spraying arm was controlled according to the sensor-based distance from the pear trees. And it could dodge obstacles to protect itself. Max and min signal values were eliminated, when five sensor signals was collected, and then signals were averaged to reduce sensor's noises. According to results of field experiment, auto control test result was better than non auto control test result. Spraying rates were 69.25% (left line) and 98.09% (right line) under non auto control mode, because pear trees were not planted uniformly. But, auto control test's results were 92.66% (left line) and 94.64% (right line). Spraying rate was increased by maintaining distance from tree.

• Research in Plant Disease
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• v.24 no.1
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• pp.41-51
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• 2018

Since fire blight disease on apple and pear was produced in Korea in 2015, there were no registered chemicals to control against this disease. Instead, several antibacterial chemicals that were registered for other bacterial diseases such as soft rot and bacterial spot have been authorized by Rural Development Administration (RDA). However, these chemicals are not tested efficacy for fire blight disease except damage by those treatments on apple and pear in Korea. Thus, we evaluated efficiency using in vitro and in planta assays of antibacterial chemicals such as antibiotics and copper compounds including kasugamycin, oxytetracycline, oxolinic acid and streptomycin, and copper hydroxide, copper sulfate, oxine copper and tribasic copper sulfate, respectively. We also tested two kinds of biological agents. As expected, significant antibacterial effect was observed in vitro test of both antibiotics and copper-based chemicals. In planta test based on disease severity including ooze and water-soaked formation on immature pears, bacterial populations on blooms, and blight lesion formation in artificially inoculated shoots, kasugamycin, oxytetracycline and streptomycin have been shown the most efficiency among tested antibiotics. Four copper-based chemicals tested in this study, control effects are little bit lower than agricultural antibiotics but they seem to be available to use in terms of winter season. Biocontrol agents were also shown possibility to treat in eco-friendly farms. In addition, there are no antibiotic resistance genes in Korean isolates against antibiotics, which were selected for suppression of fire blight in this study.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.286-296
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• 2019

Land suitability assessments have been a crucial issue for enhancing productivity in agriculture and conserving agricultural lands. Based on soil and climate information, land suitability assessment for peaches (Prunus persica) and grapes (Vitis vinifera L.) were conducted using the maximum limiting characteristic method (MLCM) in South Korea. In peaches, S1 (highly suitable) exists on 2.21% of the land, S2 (moderately suitable) on 19.20%, N1 (currently not suitable) on 12.07%, and N2 (permanently not suitable) on the remaining 66.52%. In grapes, 3.65% of the land is classified as S1, 17.98% as S2, 11.85% as N1 and 66.52% as N2. In both fruit trees, the results acquired from soil and climatic information were similar to those from soil information alone. The data also suggest that the grades by soil information were relatively low over the land. With the assumption that the more suitable area a province has, the more will be cultivated for the fruit trees, we compared the percentages of area for peach and grape farming per province with the results by MLCM, and suggested that some provinces with a small percentage of farm can be encouraged to plant more in suitable areas as dictated by MLCM for the species. In the near future, we plan to use an advanced method such as analytic hierarchy process (AHP) to conduct similar tests, in which having reference data of yields or benefits per farm can efficiently increase the accuracy of the measurements.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.859-865
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• 2011

This study looked into 110 sites of orchard fields to investigate the relationships between the physical and chemical properties of soils, including heavy metal contents, and the topographic characteristics of the fields in Jeonbuk province. The topographic distribution of orchard fields in Jeonbuk province was local valley and fans, hilly and mountains, mountain foot slopes, alluvial plains, diluvium, and fluvio-marine deposits. Forty-six percent (46%) of total orchard fields were located in the hilly and mountains. Soil texture of the local valley and fans was mostly sandy clay loam, and the soil texture of other topographical sites were varied. Bulk density, porosity, and soil hardness were not different among the various topographic sites. The content of plant available water was the highest (19.5%) in the sites of diluvium. Soil pH, electrical conductivity (EC), and exchangeable $Mg^{2+}$ content were the highest in the sites of fluvio-marine deposits, whereas the contents of soil organic matter (SOM), available phosphorus, and exchangeable $Ca^{2+}$, $K^+$, and $Na^+$ were not significantly different among the topographic sites. Also, soil pH and SOM content were generally in optimal ranges for the fruit plants in the orchard fields, but other values were mostly higher than those in optimum. In addition, the contents of heavy metals were much lower than the levels of Soil Contamination Warning Standard.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.534-539
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• 2010

'Hongro' is early-mid maturing cultivar with good quality like 'Tsugaru' and it has not preharvest drop. The CAX1 gene was introduced into Korean apple cultivar 'Hongro' by Agrobacterium tumefaciens LBA4404 harboring pBI121 to obtain transgenic apple with enhanced Ca level. The CAX1 gene playing the role of $H^+/Ca^{2+}$ transporter from Arabidopsis thaliana increases Ca concentration in several plants. Regenerated transgenic lines were confirmed by polymerase chain reaction (PCR) analysis and Southern blot analysis of genomic DNA for the existence of CAX1 gene. Southern blot analysis of 'Hongro' transformants showed that two putative transgenic lines were integrated with CAX1 gene in genomic DNA. The CAX1 comparative expression levels of two transgenic lines were higher than that of non-transformant evaluated by comparative quantification analysis using a real-time PCR. These two lines were multiplied in vitro, and micro-grafted on apple rootstocks 'M.9' in the isolated greenhouse. Since two years after micro-grafting, the fruits came into bearing. Compared to Ca level of the non-transgenic 'Hongro', that of the CAX1 transgenic 'Hongro' in the flesh and leaves was higher.

• Korean Journal of Breeding Science
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• v.42 no.5
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• pp.565-573
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• 2010

Thinning of apple fruitlets is one of the most laborious and important works for the improvement of fruit quality and for the promotion of sufficient flower bud formation to prevent alternate bearing in commercial cultivars. Lateral fruits of self-thinning apple cultivars fall naturally within 30 days after full bloom and only central fruit remains to mature. Differences of gene expression between central fruit and lateral fruit were investigated by differential display (DD) PCR. Partial cDNAs of 30 clones from the central fruit and 24 clones from the lateral fruit were selected for nucleotide sequence determination and homology searches. The levels of transcripts coding for proteins involved in pathogenesis related proteins, senescence, temperature stress, protein degradation, fruit browning, sorbitol metabolism were significantly higher in pedicels of lateral fruit than in pedicels of central fruit. On the other hand, the up-regulation of proteins involved in anthocyanin and flavanol biosynthesis and ethylene synthesis were observed in pedicels of central fruit. In Real time PCR analysis, cytochrome P450 gene was confirmed as showing a higher expression level in lateral fruit than in central fruit. The results of this study indicate that differentially expressed genes are related to self-thinning characteristics in apple tree.