• Korean journal of applied entomology
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• v.46 no.3
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• pp.409-414
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• 2007

Economic injury levels and economic thresholds were estimated for the american serpentine leafminer (Liriomyza trifolii) on greenhouse eggplant. Liriomyza trifolii density was increased until the late June and decreased after the July in innoculation on may 17. Growth of an aerial plants and fruits were not different in treatment respectively. But total number of fruits and yields were decreased on higher inoculation density. Whereas the rate of yield loss was increased. The rates of damaged leaf by L. trifolii were increased on higher inoculation density and the peak was 65%. The number of commodity fruits and the rates of commodity fruit were become lower than non-treatment (72.2%). The rates of damaged leaf area were 5.3, 11.7, 19.7, 25.7% on inoculation densities and the rates of yield loss were 0.6, 4.8, 9.8, 14.7%, respectively. There existed close correlation between rate of yield loss and inoculation density (Y = 0.76779X + 0.298354, $R^2\;=\;0.9599$). Considerated of the results, the economic injury levels of L. trifolii on eggplant greenhouse was 6.1 adults per 4 plant and the economic thresholds was 4.9 adults per 4 plant.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.367-372
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• 2011

An unknown planthopper was discovered in 2010 in an apple orchard in Sinpoong-myun, Gongju-si and in a blueberry orchard in Deogsan-myun, Yesan-gun. This pest have arrived 4 or 5 years ago and the population density then rapidly increased. It was identified as Ricania sp. by Dr. Murray J. Fletcher. Adult Ricania sp. was found on 26 plants including blueberry, grape, peach, sumac, japanese angelica, jujube, kiwi, Rubus coreanus, apple, apricot, plum and chestnut. Females lay eggs on 1-year-old branches. The mean number of eggs laid on apple and plum were 18.7 and 15.3, respectively. The mean length of egg masses on apple and plum were 12.35 and 11.45 mm, respectively. The distance between eggs laid on apple and plum branchs were 1.3 and 1.5 mm, respectively. The mean number of eggs in the same length of egg mass on apple and plum branchs were 17.1 and 13.3, respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1241-1247
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• 1997

Gel-type fermented milk was prepared from milk or mixture of milk and apple juice/grape juice. Acid production (pH change) and growth of Lactobacillus acidophilus (KCTC 2182) were studied. The effects of juice addition on sensory property of fermented milk were also studied. The pH value of samples containing mixture of milk and apple juice/grape juice (25 mL : 25 mL to 5 mL : 45 mL) was lower than that of milk sample. However, number of viable cells of L. acidophilus at 21 hr in milk and samples containing juices was similar. During lactic fermentation for 24 hr, pH of all samples dropped significantly between 6 hr and 21 hr. pH values of mixture of milk and juices were lower than that of milk sample. Growth curve showed that lag phase continued to approximately 3 hr and log phase continued to approximately 15 hr in all samples. Number of viable cells in all samples was similar Sensory evaluation showed that overall acceptability of fermented milk prepared from apple juice/grape juice and milk (15 mL : 35 mL or 5 mL : 45 mL) was better than that of reference sample. The optimum ratio of mixture of juice and milk was 15 mL : 35 mL. The score values of sensory test of fermented milk prepared from mixture of grape juice and milk were slightly higher than those of mixture of apple juice and milk.

• Korean Journal of Community Nutrition
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• v.19 no.5
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• pp.415-424
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• 2014

Objectives: Vegetables are the most left over side dishes in school lunch programs. This study intended to analyze the differences in preference for vegetables among the students of different age groups in order to determine potential ways of increasing vegetable consumption in this study group. Methods: A total of 308 primary to university students in Gyeongbuk area were recruited and a questionnaire-based survey was conducted. The preference score (7-Likert scale: very much dislike (1)~so-so (4)~like very much (7)) and intake frequency (5-Likert scale) of 48 kinds of vegetables in 4 vegetable groups, such as vegetable (fruit-, root-, leaf-, and stalk-vegetable), seaweeds, mushrooms, and kimchi were investigated, and data were analyzed by SPSS WIN (ver 12.0). Results: The preference scores of vegetables except for seaweeds were significantly different among school groups, university was the highest, followed by high school. Primary and middle school students showed the lowest preference score, especially for leaf- and stalk- vegetables. The preference score for seaweeds was the highest of 5.28, followed by kimchi of 4.99. With regard to kimchis, the preference score was the highest in university', followed by high school, middle school, and primary school' was the lowest. The number of vegetables with < 4.0 preference score was the highest in primary school of 16, 15 in middle school, 11 in high school, and 7, the lowest in university. The vegetable with preference score of < 4.0 in all 4 school groups were mallow, chard, bud, radish leaf, mugwort, butterbur and sweet potato stalk. With regard to the intake frequency of vegetables, kimchis, an indispensable part of the Korean diet, was the highest of 2 times/day, followed by cooked vegetables of 1.5 times/day. The correlation coefficients between preference scores and intake frequencies were statistically significant in all groups of vegetables. As for the coefficient of variation (CV) of preference score, primary school' was the highest and university' was the lowest. The number of vegetables with high CV and high inexperience were highest in primary school students. Conclusions: Providing more opportunities for consuming a variety of vegetables, such as leaf- and stalk-vegetable, it may be possible to increase vegetable consumption, especially for the primary school students.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.319-323
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• 2015

The objective of this study was to establish the optical storage condition in cutting slips of Lycium chinense Mill. We investigated the different influential growth factor of this plant including two soil types (soil and vermiculite) and storage methods (gauze, parafilm, vinyl, and paper). Our result revealed that the formation of axillary bud was highest ($4.8{\pm}0.75ea$) from the cutting slips stored in vinyl and vermiculite treatment. Root length was long ($2.8{\pm}0.13ea$) in parafilm storage using soil. Maximum plant height was $135.33{\pm}12.81cm$ with gauze storage using vermiculite. The number of leaves was maximum ($130{\pm}2.5ea$) at 90 days from the cutting slips of gauze storage using vermiculite. Highest number of fruit was harvested ($149{\pm}16.05ea$) from the cutting slips stored in parafilm and grown in vermiculite. It can be concluded that the storage treatment and soil type influence the affecting to general growth of Lycium chinense Mill.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.482-487
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• 2009

The apple rootstock M.26 (Malus pumila) is very popular apple rootstock with semi-dwarf habit and the trees on M.26 produce high quality fruit at a young age. Since it is prone to poor prop ability to soil, however, young trees require staking in windy locations. The rolC gene was introduced into M.26 by Agrobacterium tumefaciens LBA4404 harboring pBI121 to obtain its transformants with dwarfism and enhanced rooting ability. One regenerated transgenic line was confirmed by polymerase chain reaction (PCR) analysis and Southern blot analysis of genomic DNA for the existence of rolC gene. The characteristics of transgenic line in vitro were not significantly different from non-transgenic line except for the active root formation and lateral root number. The rolC transgenic line showed reduced stem length and increased root number in vitro. Rooting ability was examined in the isolated greenhouse after mound layering. Compared to non-transgenic M.26, rolC transgenic line showed significantly higher rooting ability. The transgenic line did not show any other observable variation in shoot phenotype compared with non-transgenic line excepting increased branching

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.1-7
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• 2022

Strawberry is a stand-out cultivating fruit in Korea. The optimum production of strawberry is highly dependent on growing environment. Smart farm technology, and automatic monitoring and control system maintain a favorable environment for strawberry growth in greenhouses, as well as play an important role to improve production. Moreover, physiological parameters of strawberry plant and it is surrounding environment may allow to give an idea on production of strawberry. Therefore, this study intends to build a machine learning model to predict strawberry's yield, cultivated in greenhouse. The environmental parameter like as temperature, humidity and CO₂ and physiological parameters such as length of leaves, number of flowers and fruits and chlorophyll content of 'Seolhyang' (widely growing strawberry cultivar in Korea) were collected from three strawberry greenhouses located in Sacheon of Gyeongsangnam-do during the period of 2019-2020. A predictive model, Lasso regression was designed and validated through 5-fold cross-validation. The current study found that performance of the Lasso regression model is good to predict the number of flowers and fruits, when the MAPE value are 0.511 and 0.488, respectively during the model validation. Overall, the present study demonstrates that using AI based regression model may be convenient for farms and agricultural companies to predict yield of crops with fewer input attributes.

• Journal of Mushroom
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• v.20 no.3
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• pp.107-112
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• 2022

This study was conducted to reduce the phenomenon of biased cultivation and to pursue the diversification of mushroom items. We focused on developing Sparassis latifolia varieties with a short cultivation period, stable pinheading, and a high yield. We have collected and determined the characteristics of genetic resources domestically and abroad since 2016. We bred the unique domestic variety, "Hanyeoul" and the results of this study are as follows. The optimal temperatures for mycelial growth and fruit body growth were 22~25℃ and 19~21℃, respectively. The color of the pileus was pale-yellowish white, which was similar to the color of the control variety, "Neoul". The number of days required for cultivation was 125 for bottle cultivation and 98~102 for bag cultivation, which was shorter than the number of days required for the control variety. Bottle cultivation took 39 days shorter for the new variety than the control variety. The fruiting body of the new variety was similar in size or larger than that of the control variety. The pinheading rate was more than 90% in bottle cultivation and bag cultivation, which was more stable than pinheading in the control variety. The yield was 79.1 g/bottle (1,100 cc) for bottle cultivation, which was 22.6% higher than the yield of the control variety, and 641.1~689.5 g/bag (2.6 kg) for bag cultivation, which 5.8~10.4% higher than yield of the control variety.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.24-42
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• 1983

To develop Ilex cornuta which grow naturally in the southwest seaside district as new ornamental tree, the author chose I. cornuta growing in the four natural communities and those cultivated in Kwangju city as a sample, and investigated its ecology, morphology and characteristics. The results obtained was summarized as follows; 1) The natural distribution of I. cornuta marks $35^{\circ}$43'N and $126^{\circ}$44'E in the southwestern part of Korea and $33^{\circ}$20'N and $126^{\circ}$15'E in Jejoo island. This area has the following necessary conditions for Ilex cornuta: the annual average temperature is above $12^{\circ}C$, the coldness index below $-12.7^{\circ}C$, annual average relative humidity 75-80%, and the number of snow-covering days is 20-25 days, situated within 20km of from coastline and within, 100m above sea level and mainly at the foot of the mountain facing the southeast. 2) The vegetation in I. cornuta community can be divided that upper layer is composed of Pinus thunbergii and P. densiflora, middle layer of Eurya japonica var. montana, Ilex cornuta and Vaccinium bracteatum, and the ground vegetation is composed of Carex lanceolata and Arundinella hirta var. ciliare. The community has high species diversity which indicates it is at the stage of development. Although I. cornuta is a species of the southern type of temperate zone where coniferous tree or broad leaved, evergreen trees grow together, it occasionally grows in the subtropical zone. 3) Parent rock is gneiss or rhyolite etc., and soil is acidic (about pH 4.5-5.0) and the content of available phosphorus is low. 4) At maturity, the height growth averaged $10.48{\pm}0.23cm$ a year and the diameter growth 0.43 cm a year, and the annual ring was not clear. Mean leaf-number was 11.34. There are a significant positive correlation between twig-elongation and leaf-number. 5) One-year-old seedling grows up to 10.66 cm (max. 18.2 cm, min. 4.0 cm) in shoot-height, with its leaf number 12.1 (max. 18, min), its basal diameter 2.24 mm (max. 4.0 mm, min. 1.0 mm) and shows rhythmical growth in high temperature period. There were significant positive correlations between stalk-height and leaf-number, between stalk-height and basal-diameter, and between number and basal diameter. 6) The flowering time ranged from the end of April to the beginning of May, and the flower has tetra-merouscorella and corymb of yellowish green. It has a bisexual flower and dioecism with a sexual ratio 1:1. 7) The fruit, after fertilization, grows 0.87 cm long (0.61-1.31 cm) and 0.8 cm wide (0.62-1.05 cm) by the beginning of May. Fruits begin to turn red and continue to ripen until the end of October or the beginning of November and remain unfading until the end of following May. With the partial change in color of dark-brown at the beginning of the June fruits begin to fall, bur some remain even after three years. 8) The seed acquision ratio is 24.7% by weight, and the number of grains per fruit averages 3.9 and the seed weight per liter is 114.2 gram, while the average weight of 1,000 seeds is 24.56 grams. 9) Seeds after complete removal of sarcocarp, were buried under ground in a fixed temperature and humidity and they began to develop root in October, a year later and germinated in the next April. Under sunlight or drought, however, the dormant state may be continued.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.201-210
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• 1998

Sex ratios, and patterns of tree size and growth variation, resource allocation, spatial and age class distribution between the sexes were investigated in natural populations of the sexual trees, R. trichocarpa and R. sylvestris, and the mainly asexual, clonal tree, R. javanica of the dioecious Rhus (Anacardiaceae) distributed in Korea. Sex ratios for three species exhibited a significant degree of female bias, but among the populations, sex ratios were seen to vary quite widely. The measurement of tree size and annual increment of male trees in R. trichocarpa and R. sylvestris were significantly higher than those of female trees, but not significantly different in R. javanica. In all of the species, flowering branch number per individual and inflorescence number per branch of males outnumbered those of females. Branch number per individual, rachis(leaf) number per branch and rachis(leaf) number per inflorescence were more in females than in males. These results were considered as reproductive efforts to increase the pollen supply in males and the fruit production in females. Spatial distribution analysis in two different populations of R. trichocarpa indicated that males and females were randomly distributed in space, but seedlings were clumped around parental trees. Analysis of age class distributions between the sexual reproduction trees, R. triclaocarpa and R. sylvestris, and the asexual, clonal tree, R. javanica showed a different distribution in frequencies of males and females in each age class. These results showed that sexual and asexual reproduction tree species had almost different preference of habitats, and different sex ratio and annual growth.