• Korean journal of applied entomology
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• v.55 no.3
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• pp.297-301
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• 2016

Seasonal occurrence patterns of Synanthedon tenuis and S. bicingulata (Lepidoptera: Sesiidae) were monitored in sweet (non-astringent) persimmon orchards in the southern part of Korea from 2013 to 2105, using sex pheromone traps of the respective species. The two species occurred twice a year. Peak occurrences of the $1^{st}$ and $2^{nd}$ generations of S. tenuis were observed in late May nd mid to late September, respectively, while those of S. bicingulata were in early May to early June and mid to late September, respectively. Pooled catches of S. tenuis during the three years from the three locations showed that the $1^{st}$ generation was 1.9 times larger than the $2^{nd}$ generation. In contrast, pooled catches of S. bicingulata showed that the $2^{nd}$ generation was 1.3 fold larger than as the $1^{st}$ generation. However, it remains unclear whether S. bicingulata damages persimmon tree or not.

• Food Science and Preservation
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• v.16 no.4
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• pp.459-462
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• 2009

'Fuyu' (Diospyros kaki L.) is an important sweet persimmon cultivar, and the fruits are often stored in a modified atmosphere after harvesting in South Korea. However, blossom-end browning and darkening of fruit often occur after harvest or during storage, which decreases fruit quality in the fresh fruit market. High fruit calcium concentration would reduce oxidation of phenolic compounds in the cytoplasm such oxidation is responsible for fruit browning. This study investigated the effects of soluble calcium fertilization and foliar application, and indole-3-butyric acid (IBA) fertilization on fruit quality and browning. Trees received one of the following five treatments: 1) control (no calcium or IBA); 2) calcium fertilization (Ca FG, 2 mL per tree); 3) calcium foliar application (Ca FA, 2 mL); 4) calcium and IBA fertilization (Ca+IBA) 5) IBA fertilization (IBA, 2 mL. Fruit calcium concentration was highest in trees treated by Ca FA, and lowest in control trees. Generally, fruit calcium concentration was high in the stem end but low in the blossom end, which usually first develops fruit-browning symptoms. There were no apparent differences in fruit qualities such as firmness, soluble solid content, and weight among treatments. Fruit browning occurred at frequencies of about 14%, 20%, and 50% on Ca FA, Ca FG, and control trees, respectively. Therefore, the improved fruit calcium level seen when trees received Ca or IBA application tended to prevent fruit browning, which increased fruit quality and storage properties.

• 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.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.50-56
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• 2001

In vitro experiments, several fungicides including prochloraz, tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 85% inhibition of mycelial growth of Pestalotiopsis theae (SP-3). Dichlofluanid and chlorothalonil inhibited mycelial growth at the rate of 10 and 33%, however benomyl did not inhibit mycelial growth of the fungus. Minimum inhibitory concentration(MICs) of iminictadine-triacetate on the mycelial growth of SP-3 isolate was $10{\mu}g/m{\ell}$, but that of P. theae $\underline{MAFF}$ 752002 and P. longiseta $\underline{MAFF}$ 752001 was $1{\mu}g/m{\ell}$. MIC of benomyl, chlorothalonil, dichlorofluanid was $1,000{\mu}g/m{\ell}$, and that of fludioxonil, fluazinam, tebuconazole was $10{\mu}g/m{\ell}$. Conidial germination was inhibited more than 80% in tile medium which contained $1{\mu}g/m{\ell}$ of prochloraz, tebuconazole, fluazinam, fludioxonil, and minoctadine-triacetate. Control values of benomyl, chlorothalonil and dichlofluanid were 40, 60 and 30%, respectively. The controlling effect of iminoctadine-triacetate ($10{\mu}g/m{\ell}$) aganist P. theae (SP-3) in leaf disc test was more than 93%, but benomyl and dichlofluanid could not control leaf blight disease caused by P. theae (SP-3). Tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 94% of protective and curative effect of leaf blight of sweet persimmon, while, benomyl and dichlofluanid did not show any control effect of the disease.