• Korean journal of applied entomology
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• v.34 no.4
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• pp.295-299
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• 1995

This study was conducted to find the control methods, status of overwintering and seasonal occurrence of Erioccoccus largerstroemiae on persimmon trees in Ch'ondo area, Kyongbuk province in Korea. Usually, overwintering eggs were sheltered in bark, among them the rate of alive eggs was 28.7%. The activiation of garpe-myrtle scale showed from late April, and they have three generations per year. The first occurrence of larval stage of Erioccoccus largerstroemiae starts from late June to early July, the second occurrence begins from middle August to late August, and from late June to early July, the second occurrence begins from middle August to late August, and from middle September to late September is the third, thus, three peaks of occurrence revealed in early July middle August, and late September respectively. Average number of eggs conceived in female adult was 229.3. Spray effect of chemical control showed as follows; lime sulfur with tow applications of pesticides (late June, late August) at 97.8%, machine oil with tow applications of pesticides (late June, late August) at 96.8%. And during the growing period, the spray results using three applications of pesticide only (late June, late August, amid September) showed 77.2% in field condition.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.232-238
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• 1997

Culture conditions affecting mycelial growth and sporulation of P. theae, SP2, SP3 and P. longiseta which causing leaf blight on oriental persimmon leaf blight have been investigated. The optimum temperature for the mycelial growth and sporulation on potato dextrose agar was $25{\sim}30^{\circ}C$ in all the fungi, but was inhibited and finally arrested at 10 and $30^{\circ}C$. The optimum pH for mycelial growth and sporulation were ranged at pH 4.5~5.0 and 5.0~6.0 in all the fungi. Lenonian agar, potato sucrose agar and oatmeal medium were good culture media for the mycelial growth and sporulation of all the fungi. The effective sources of nitrogen and carbon for the mycelial growth were tryptone, glycine, starch, dextrose, galactose and lactose. Glutamic acid, peptone and tryptone were good nitrogen sources for sporulation of the fungi. Sucrose, starch and galactose were also good carbon sources for sporulation. Generally, vitamins had no effect on mycelial growth and sporulation. The pH of the potato dextrose broth inoculated with SP2, SP3 and P. theae and P. longiseta was changed from 7.0 to 4.5~4.7 and 5.0~5.4 after incubating for 10 days, respectively. But, the initial pH of the medium adjusted to 5.0 was lowered to 4.5~4.7 after incubating for 10 days.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.395-399
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• 2019

The purpose of this study was to investigate shooting and fruiting characteristics of persimmon 'Hachiya' affected by sub-zero temperature at early budding stage. The number of developed shoots, and the number of shoots with young fruits, and the shooting and fruiting of terminal buds of one-year-old branch (1YOB) were significantly decreased with the sub-zero temperature treatment (SZT). The number of shoots developed in the top of 1YOB decreased 47.2% due to SZT. The number of shoots with fruits was significantly decreased at 50% or higher in non-budding rate of 1-YOB. Especially the number of fruits (Y) at the three terminal buds of 1YOB was significantly affected by SZT and the non-budding rate (X) as Y = -0.145X + 12.950 ($r^2=0.4672^*$). Therefore, in the early budding stage of persimmon, when tree is affected by SZT ($-2^{\circ}C$, 3 hours), shoots growth is reduced and increase of 10% in non-budding rate reduces 1.4 of fruits per the three terminal buds of 1YOB.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.488-494
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• 2015

This study aims to develop and apply a standard management self-diagnostic table for forestry households to better manage their astringent persimmon production. The diagnostic table consisted of 3 categories (general status of a forestry household, management performance indicators, level of management) and 18 subcategories. The current management status across 241 households was surveyed among 10 chief astringent persimmon producing municipalities. Scores from the 18 subcategories were aggregated for a total score to evaluate and compare different levels of management. The respondents scored an overall average of 57.4, 62% of which were placed between 40 and 60. Upon close examination Chungcheongnam-do scored a very low score in the 'management system-tree height' subcategory with respect to the average score potentially because of the large population of aged trees in the region. The national average in the 'production skills-time of fruit load adjustment' subcategory was only 1.96 because unlike sweet persimmons astringent persimmons adjust their own load by inducing physiological fruit drop. The national average in the 'management/sales skills-material purchase' subcategory was 2.01; over 60% of the respondents indicated a preference for independent selection and purchase for most materials. The households preferring a group purchase tended to utilize the regional co-op.

• Korean Journal of Organic Agriculture
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• v.25 no.2
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• pp.445-460
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• 2017

This study was carried out for three years from 2013 to 2015 to investigate the actual condition of pest control of domestic persimmon organically cultivated farmers, to select environment - friendly pest control materials for major pests, and to conduct field test of established control system. The main cultivated cultivar of the reader farmer of organic cultivation was "Buyou" and sprayed organic agricultural material 9~17 times per year for pest control. The most harmful pests were anthracnose, bugs, persimmon fruit worm, and scales, etc. The control materials used were organic lime sulfur mixture, red clay sulfur, emulsifier, bordeaux solution, and self-made plant extracts using garlic, ginkgo nut and pine tree. The effective materials for controlling anthrax were lime sulfur mixture and red clay sulfur. Garlic oil + citronella emulsion, shrubby sophora seed extract + tea extract was effective to control Riptortus clavatus and Euproctis subflava. When installed 60 ea per 10a of mating disruption trap in a sweet orchard, the fruit setting rate was improved by 30%. The results of field test of control system to control 10 times a year in organically grown persimmons were able to harvest fruit of 70.7%. However, since any kinds of pesticides can not be sprayed during the harvest season in September and October, the damaged by bugs did not decreased, and further research is needed.

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.55-60
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• 2013

BACKGROUND: The buds of persimmon trees are susceptible to cold damage, often with the late frost, at the time of budburst. This study was conducted to determine effect of the cold damage on shoot and fruit growth the current season. METHODS AND RESULTS: 'Fuyu' trees, grown in 50-L pots, were placed for 1 h at $-2.2{\pm}0.5$, $-2.6{\pm}0.5$, or $-3.0{\pm}0.5^{\circ}C$ within a cold storage, at their budburst on April 5. Some trees under ambient temperature at $10-17^{\circ}C$ served as the control. Cold damage of the buds containing flower buds was 54% at $-2.2^{\circ}C$, and significantly increased to 95% at $-3.0^{\circ}C$. The bud damage included the complete death of all, complete death of main buds only, or the late and deformed shoot growth in the spring. Number of flower buds in early May dramatically decreased as the damage ratio increased. Since the thinning of flower buds in mid-May and fruitlets in early July was done in no or slightly damaged trees, the final number of fruits and yield did not decrease compared with the control when the damage increased by 60% and 70%, respectively. Average fruit weight and skin coloration tended to be better with increasing bud damage. Shoot growth was more vigorous in those trees whose buds were severely damaged by low temperature. CONCLUSION(S): Shoot growth and the yield may depend on the number of flower buds and percent fruit set after the cold damage.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.279-288
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• 2003

A total of 29 scale insect species belonging to 21 genera of five families were recognized on 11 fruit trees on the basis of specimens collected from 2001 to 2002 and specimens deposited in the Insect Collection of NIAST in Korea. Ten species were recognized on apple, nine species on pear, three species on peach, 14 species on unshiu orange, nine species on persimmon, two species on Japanese plum, one species on japanese apricot, 10 species on junos orange, one species on grape, four species on jujube and three species on kiwi fruit.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.305-311
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• 2002

Asiacornococcus kaki (Kuwana) known as a serious pest on Diospyros kaki Thunb. has been reported erroneously as Eriococcus lagerstroemiae Kuwana. These two species were redescribed and illustrated for correct identification by the morphological characters of adult females with known host plants. Asiacornococcus Tang & Hao is a newly known genus from the Korean Peninsula.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.540-544
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• 2001

The effect of long day treatment on the growth and flower bud differentiation of persimmon tree grown in a heated plastic house was investigated. The rate of leaf sprout was 65% in the long day treatment and 71% in natural day (control). In the long day, the shoot grew 16.7 cm longer, full bloom and harvest days were shorter, fruit weight was 16% lighter, and the sweetness and firmness of fruit were lower. The photosynthesis rate in the long day treatment was higher, showing the tendency of increasing with time. However, the rate of photosynthesis increased after 1600 hours showed higher than the control. Carbohydrate accumulation in the shoot was decreased, with higher nitrogen content and lower C/N ratio in the long day. The number of flower primordia per bud was less, and the days for differentiation was longer in the long day.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.269-276
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• 1990

This study investigated host range, seasonal occurrence and developmental characteristics of Ceroplastes pseudoceriferus Green on persimmon trees. The host plants covered 34 families and 66 species, including newly recorded species of Chenopodum album var. centrorubrum, Glycine max, Begonia semperflorens, Pharbitis nil, Perilla frutescens var. japonica and Erigeron canadensis. There was one generation of C. pseudoceriferus a year with larval stage expanding from mid-June to mid-October. Average number of eggs laid per female was 1,073$\pm$177.3. Hatching rate was 97.3% and was not affected by temperatures and photoperiods. Stadium varied as 23.4 days in eggs, 128.3 days in larvae and 213.3 days in female adults including overwintering periods at natural condition.