• Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.121-128
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• 2021

The variations of morphological features, density and biomass of vegetative shoots and characteristics of reproductive shoots of Zostera caespitosa were examined in Tongyeong, Korea. Morphological features such as leaf length, width and sheath length of Z. caespitosa showed significant seasonal variation (p < 0.001). The highest aboveground value was recorded in late spring to summer and the lowest value in winter. Density and biomass also showed seasonal variations. Annual average shoot density and biomass of Z. caespitosa were recorded as 1,223.4 leaf m^-2 and 5,956.9 g w.w.m^-2, respectively, and had the highest value in June and lowest values in November and January. Reproductive shoots were observed from April (13℃) to June (21℃). Pistils erected outside sheath, anther dehiscing and small embryos were found in April. Mature fruit and released seeds were found in May and June. These results suggest that this species had a high growth rate in late spring and early summer (15℃-20℃). Reproductive shoots of Z. caespitosa may initially appear at about 10℃ in spring and seed have been released at about 20℃ in fall.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.148-152
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• 1994

This study was carried out to investigate insect specles of Kiwi fruit, and ecological characteristicsof Stathmopoda m Chonnam province from 1991 to 1993 Twelve families and thirteen specieswere identified during the study. Sfothmopoda aurijerello and mulberp scale were key insect pestsamong them. The body sizes of each stage of S. a~irijereilo was measured and found to be 0.12 mmfor egg, 9.8 mm for mature lawa. 5.9 mm for pupae and 123mm for adult with opened wings.S, ouriferelia appers to have two generations a yea Adults occut~ed from late May to midJulyand mid-August to early September Mth two peaks m early to midJune and late August. Changein age structure (% lawe: % pupae) over time was 100: 0 in earlyJul, 96. 1 . 3 9 in midduly. 64.9:35 1 in late July. 19.8 . 80 2 in early August, and 0 : 100 in mld-August Damaged fruit was 4 6%in early July, increase above 40% 1" midJuly, and then the damage surpassed the damage threshold.The rate of fruit damaged was 45.9%, and there wbi no significant dtfferences among countiesDamaged parts of fruits were manly fruit apex Mth 70% and followed by fruit stalk w~th 11.1%.The rate of fruit damaged by varieties were Hayward with 25.7%. Monty with 17 5%. Hyangrokwith 13.9%, Abott with 9.3% and Bruno with 6.0%. with 9.3% and Bruno with 6.0%.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.169-174
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• 1994

A new unidentified pear leaf spot disease presumed to first occur in the late 1970's has recently become prevalent over the pear growing areas, and caused the greatest problem for pear production in Korea. The disease began to develop on pear leaves at mid- to late May, peaked at mid- to late une, but stopped further development until September in cool climate. Leaf lesions are 0.9∼2.5 mm in diam., oval or irregular to rectangular in shape, first appeared reddish purple, later changed to dark brown, and to whitish grey in the late season. Lesions were limited to appear only on the mature, hardened leaves, initially from leaf margin or near the leaf veins, and later scattered over the leaf surface. Individual lesions usually did not enlarge, but often coalesced each other, commonly causing shot holes and eventual early falling. The disease was most severe on the major pear cultivars Niitaka and Okusankichi ranged with 4 to 100% infections in trees, depending on the orchards, but not on the cultivar Chojuro. Damages from the disease included lower fruit weight, and higher acid and less sugar content in fruits, resulting in lowering the overall fruit quality. Etiology of the disease including identification of the causal organism is in a separate paper.

• Korean Journal of Plant Resources
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• v.10 no.3
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• pp.213-220
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• 1997

The present study has been undertaken to characterize availability of citrus as a medicinal plant with antineoplastic property. The crude extracts from 40 species of fruits with 12 species of the local Citrus in Cheju island were evaluated on their potential activities against mouse P388 lymphocytic leukaemia in vitro. The percent cytotoxicity varied from 25.40 to 97.94% at a concentration of $100{\mu}g/mL$. Among 40 spp., 8 species showed high toxicity more than 90% against P388 cells and Cheongkyool(C. nippokoreana) exhibited the most cytotoxicity as 97.94%($IC_{50}=20.2{\mu}g/mL$). Nine varieties of C. junos were showed insiginicant cytotoxicity. In trifoliate orange, immature fruit was stronger than mature and peel extract showed higher cytotoxicity($IC_{50}=18{\mu}g/mL$) than the other tissues. Hexane fraction from methanol(MeOH) extract of trifoliate orange showed highly significant inhibition of cell growth($IC_{50}=3.9{\mu}g/mL$). In addition, its cytotoxicity increased remarkably from 3.95 to $0.40{\mu}g/mL$ as exposure time legthened. Cytotoxic activities of crude extracts were decreased considerably during a six months storage period. It was apparent that there is considerable variation in cytotoxicity, depending upon species, maturity and storage time of extracts. There was no meaningful cytotoxic difference between archicitrus and metacitrus in the genus Citrus.

• Journal of Forest and Environmental Science
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• v.33 no.4
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• pp.270-280
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• 2017

Selection of superior phenotypes of fruit trees and products based on established criteria by local people is a prerequisite for future species domestication and conservation. Thus the study objective was to identify the local people's perceptions and preferences on baobab trees and products. A sample of 142 respondents was randomly selected using structured interviews in Blue Nile and North Kordofan, Sudan in 2013. Descriptive analysis was employed using SPSS and Excel programs. The study results indicated that local people use the morphological characteristics of the tree (leaves, fruits, seeds, kernels and bark) to differentiate individual trees. Based on the perceptions, local people recorded trees with delicious leaves, white pulp color, big fruit size and mature capsule size, and high pulp yield as criteria for differentiating between baobab trees in the study areas. In contrast, the undesirable traits were connected to trees with acidic pulp, slimy pulp, bitter leaves, and low pulp yield. The study concluded that the ethnobotanical knowledge of the baobab tree and its products may play an important role in tree domestication and improvement in Sudan. However, further research on tree genetics is needed to complement the ethnobotanical knowledge for baobab resources domestication and conservation.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.24-31
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• 2016

This study investigated the effects of flower and fruit thinning agents on fruit set and harvested fruit quality attributes in 'Gamhong' apples. Lime sulfur, MaxCel (1.9% BA), and Fruitone (3.5% NAA) were applied either at post-bloom or fruitlet stages to mature 'Gamhong/M.9' trees. In 2011, the numbers of fruits per cluster in terminal flowers were 1.74, 0.82, and 1.15 for the control, lime sulfur, and Maxcel (applied at 10-mm fruit stage) treatments, respectively. The percentages of single fruit per cluster were 36.0, 47.9, and 48.7% for the control, lime sulfur, and Maxcel (10 mm) treatments, respectively, while the percentages of clusters with three fruits per cluster were 22.9, 1.4, and 5.8%. In lateral flowers, fruit numbers per cluster were 1.20, 0.36, and 0.50 for the control, lime sulfur, and Maxcel (10 mm) treatments, respectively. In 2012, all the thinning treatments showed a positive effect on flower and fruit thinning, compared with the control. Moreover, the treatment with thinning agents did not affect fruit quality. Overall, the results suggest that a single application of flower or fruit thinning agents would be sufficient, rather than the mixed application of thinning agents, based on the observed decrease in fruit setting.

• Horticultural Science & Technology
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• v.29 no.6
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• pp.655-658
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• 2011

A new cultivar 'Hongan' was originated from an artificial cross between 'Fuji' and 'Jonathan' carried out at National Institute of Horticultural & Herbal Science in 1993. The cultivar was preliminarily selected among the elite siblings for its high fruit quality in 2002. After regional adaptability test at five districts for subsequent four years as 'Wonkyo Ga-32', it was finally selected in 2006. 'Hongan' is characterized by the following. Optimum harvest time is late September. Shape of the mature fruit at 309 g on mean weight is globosity with a light red skin on a greenish yellow ground and yellowish white flesh. The fruit contains favorable total soluble solids at $13.7^{\circ}Brix$ and an acidity at 0.28%. Safe storage period for the fruit is 3 weeks at room temperature. It is resistant to Bitter rot. 'Hongan' also reveals a physiological cross compatibility with leading cultivars such as 'Gamhong' and 'Tsugaru' in addition to its maternal parent 'Fuji'. Tree topology is semi-spreading with vigorous growth habit.

• Korean journal of applied entomology
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• v.50 no.3
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• pp.203-208
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• 2011

This study was conducted to evaluate Geometridae (Lepidoptera) species as pests and the damage they cause in citrus orchards in Jeju, Korea. Seven geometridae species occurred in citrus orchards: Ascotis selenaria, Ectropis excellens, Menophra senilis, Biston panterinaria, Ourapteryx nivea, Odontopera arida and Hypomecis punctinalis. Among them, A. selenaria was most abundant, followed by E. excellens and M. senilis. Most Geometridae larvae fed on citrus leaves, but A. selenaria larvae ate fruits and leaves. Fruit damage of Citrus unshiu appeared as gnawed scars caused by young larvae feeding on fruit surface. Fruit damage on Shiranui fruits appeared as a wide hole or deep scars caused by feeding by mature larvae (6th instar). Citrus leaves damage due to Geometridae larvae was high during May to June. Fruit damage started in late June as the spring-shoots of citrus hardened and increased sharply in late July. In the field experiment, fruit damage in the late season reached 4.2% in both 2008 and 2009 and reached 5.2% in 2010. In citrus orchards, A. selenaria larvae started to appear in mid-May and their populations peaked in mid June, late July, and early to mid-September. Adult males of A. selenaria had a maximum peak in mid-May, and two other peaks in early to late July and late August to early September. A. selenaria male adults were collected in a pheromone traps constantly throughout Jeju Island.

• Journal of agriculture & life science
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• v.43 no.2
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• pp.23-30
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• 2009

The object of this study was to evaluate the effect of the gibberellin treatment on fruit enlargement and ripening promotion in 'Niitaka' pear(Pyms pynfolia). Fruit weight was similar between $GA_{4+7}$ treatments and the gibberellin-paste control, but fairly increased of fruit weight compared to non-treatment Most effective time for $GA_{4+7}$ treatment to increase diameter and length was on 35 and 40 days after full bloom, respectively. Shape index was similar in all treatments. Fruit enlargement at the period of early growth, $GA_{4+7}$ 2.4% treatment was remarkably effective than $GA_{3}+GA_{4+7}$ 2.7% treatment or non-treatment However at the period of maturity, $GA_{4+7}$ 2.4% treatment and $GA_{3}+GA_{4+7}$ 2.7% treatment showed little differences in fruit enlargement and coloring. In maturing promotion effect, young fruit treated with $GA_{3}+GA_{4+7}$ showed similar fruit coloring to ethephon treatment on 35 days after full bloom, and both of those treatments promoted fruit coloring than non- treatment about 6 days. $GA_{3}+GA_{4+7}$ treatments resulted higher solid content and decreased acidity than non-treatment However, there was no differences in fruit hardness comparing to non-treatment As a result, gibberellin was most effective in fruit enlargement, so as all $GA_{3}+GA_{4+7}$ treatments were more effective on fruit enlargement than ethephon treatment or non-treatment Specifically, when $GA_{3}+GA_{4+7}$ was treated 35days after full bloom of flower, the diameter, the length and the shape of fruit index were best, and fruit coloring was good as well.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.15-16
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• 1999

'Cheonhong'was released by the National Horticultural Research Institute in 1992 as a new mid-ripening, yellow-fleshed, and freestone nectarine variety, which originated from open-pollinated seeds of 'Garden State' nectarine collected in 1978. This was tested as 'Wonkyo Da-03' at 4 areas for 4 years from 1989. 'Cheonhong' is resistant to fruit cracking during rainy season and russeting. Fruits mature about 15 days before 'SunGlo' and have rich-flavor and good quality.