• The Plant Pathology Journal
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• 제19권5호
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• pp.227-230
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• 2003

Ripe rot was commonly found in overripe kiwifruits (Actinidia deliciosa) during a disease survey conducted in Jeju and Jeonnam provinces in Korea in 1999. While the disease did not manifest any clear external symptoms on kiwifruits, it caused portion of the fruit surface to collapse. Watersoaked flesh tissue could be seen on the sunken part when the skin of the collapsed portion was peeled off. The milky internal symptom with dark green margin developed concentrically as the fruit ripened. A species of Botryosphaeria was consistently isolated from lesions showing typical symptoms of ripe rot on kiwifruit, and its pathogenicity was confirmed by artificial inoculation test on healthy kiwifruits. The fungus was also pathogenic to apple and pear. The mycological characteristics of the fungus were consistent with those of Botryosphaeria dothidea. This is the first report on the detailed mycological characteristics of the causal organism of post-harvest ripe rot of kiwifruit in Korea.

• 농업과학연구
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• 제50권3호
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• pp.357-364
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• 2023

In this study, we propose a ripe tomato bunch localization method based on convolutional neural networks, to be applied in robotic harvesting systems. Tomato images were obtained from a smart greenhouse at the Rural Development Administration (RDA). The sample images for training were extracted based on tomato maturity and resized to 128 × 128 pixels for use in the classification model. The model was constructed based on four-layer convolutional neural networks, and the classes were determined based on stage of maturity, using a Softmax classifier. The localization of the ripe tomato bunch region was indicated on a class activation map. The class activation map could show the approximate location of the tomato bunch but tends to present a local part or a large part of the ripe tomato bunch region, which could lead to poor performance. Therefore, we suggest a recursive method to improve the performance of the model. The classification results indicated that the accuracy, precision, recall, and F1-score were 0.98, 0.87, 0.98, and 0.92, respectively. The localization performance was 0.52, estimated by the Intersection over Union (IoU), and through input recursion, the IoU was improved by 13%. Based on the results, the proposed localization of the ripe tomato bunch area can be incorporated in robotic harvesting systems to establish the optimal harvesting paths.

• 한국응용곤충학회지
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• 제1권
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• pp.47-50
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• 1962

만부병은 포도의 착색기부터 장마가 오면 격발하는 병해로서 우리나라에 있어서 피해가 심함은 물논 방제가 어려운 것으로서 본 시험은 피대와 약제살포를 겸하는 것과 약제살포만을 하여 그 효과를 비교코저 원예시험장 과수과 포도원에서 품종 켐벨얼리를 공시하여 시험하였다. L 유대구는 무대구보다 약제간이나 무처리간에 있어서 포도만부병을 방제하는데 효과적 이였다. 2. Tuzet와 Delan은 유대구나 무대구에 있어서 다른 처리구보다 포도만부병방제에 효과적이었다

• Preventive Nutrition and Food Science
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• 제6권2호
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• pp.133-135
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• 2001

The edible part of cucurbita moschata Duch, which is commonly used as a Korean traditional medicine as well as a popular food source, was studied to isolate anti-complementary substance. Extracts of Cucurbita moschata Duch showed significant anti-complementary activities on the classical pathway of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the complement system. Especially, the ripe Cucurbita moschata Duch had more activity than that of the green one in terms of the overall anti-complementary activity. Among the extracts of various organic solvents of the ripe Cucurbita moschata Duch, chloroform and ethyl-acetate extracts, which are non-polar solvent extracts, showed the strongest activities. These results suggest that the major difference in the solvent extraction for the anti-complementary substances depends on the change in the chemical composition such as the fatty acid with the degree of ripening.

• The Plant Pathology Journal
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• 제20권4호
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• pp.258-263
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• 2004

Ripe fruit of pepper (Capsicum annuum) showed resistance to Colletotrichum gloeoporioides, but unripe fruit was susceptible. We previously isolated the PepTLP gene that induced in both unripe and ripe fruit by fungal infection and wound, and only in ripe fruit by jasmonic acid (JA) treatment. To examine further regulation of PepTLP, the action of specific agonist and antagonists of known signaling effector on the .PepTLP expression by fungal infection, wound, and JA was investigated. A similar dephosphorylation event negatively activated all the PepTLP expression in the ripe fruit by fungal infection, wound, and JA. The induction of PepTLP expression by wound is differentially regulated via phosphorylation and dephosphorylation step during pre- and post-ripening, respectively. In addition, the induction of PepTLP expression in the ripe fruit by wound and JA is differentially regulated via dephosphorylation and phosphorylation step, respectively. Only both wound and JA treatment has synergistic effect on the PepTLP expression in the unripe fruit. Both SA and JA treatments on the unripe fruit, and both wound or JA and SA on the ripe fruit could not do any effect on the expression of PepTLP. These results suggest that the induction of PepTLP expression is differentially regulated via complex regulatory system against fungal infection, wound, and JA treatment during pre- and post-ripening of pepper fruit.

• Natural Product Sciences
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• 제20권4호
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• pp.290-295
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• 2014

The triterpenoids contained in four Rubus species (Rosaceae) were quantitatively analyzed using HPLC to select plants with large quantities of niga-ichigoside $F_1$. Unripe fruits, ripe fruits, and leaves were extracted to estimate the quantity of niga-ichigoside $F_1$, together with Rubus-specific $19{\alpha}$-hydroxyursane-type triterpenoids, euscaphic acid, tormentic acid, and kaji-ichigoside $F_1$, and a dimeric triterpenoid coreanoside $F_1$. Niga-ichigoside $F_1$ was most abundant in the leaves of R. crataegifolius (23.4 mg/g dry weight). The amount of triterpenoid in the black, ripe fruits of R. coreanus was lower than the unripe fruits of the same plant. On the other hand, the ripe fruits of three plants, R. crataegifolius, R. parvifolius and R. pungens var. oldhami, which are reddish, contained higher or similar level of triterpenoids than their unripe fruits. In addition, the concentration of niga-ichigoside $F_1$ in the ripe fruit of R. crataegifolius was 20.5 mg/g, suggesting that the fruits could be used as a functional food. Methyl gallate and ellagic acid were used as quantitative indices of total tannin. Methyl gallate levels were higher in ripe fruits than unripe fruits in R. crataegifolius, R. pungens var. oldhami, and R. parvifolius. In R. crataegifolius, the quantity of methyl gallate was 30.5 mg/g in ripe fruit, but 1.19 mg/g in unripe fruit.

• 식물병연구
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• 제7권3호
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• pp.140-144
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• 2001

1997년부터 1999년까지 켐벨얼리품종을 대상으로 대구, 영천, 김천지방에서 탄저병의 발생소장을 조사한 결과 7월과 8월의 강우와 상관이 있었으며 7월 하순부터 초발 되었다. 과방에 봉지를 씌워 탄저병의 주 감염시기를 조사하였을 때 7월 25일 이후 봉지를 씌운 과방에서 발병이 되었으며 시기별로 외관상 건전한 과방을 습실처리하여 잠복감염을 조사하였을 때 7월 25일 이후에 수확된 과일부터 발병 되었다. 탄저병 포자현탁액을 포도표면에 접종하고 균사의 발달을 관찰한 결과 24시간에 부착기가 관찰되었으며 48시간후에는 전면이 균사로 덮여졌다. 접종후 경과시간별 발병정도는 24시간이상 발병조건 부여시 발병이 되었다. 포도 탄저병 방제방법으로는 타로닐 ·마이탄 수화제를 7월 20일 경부터 4회살포시 높은 방제가를 보였다.

• 한국패류학회지
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• 제22권2호
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• pp.143-150
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• 2006

The gonad index, condition index, reproductive cycle and spawning of the pen shell Atrina (Servatrina) pectinata were investigated using samples from the subtidal zone of Nokdo on the Boryeong coastal waters of Korea. Samples were collected monthly by SCUBA divers for one year from January to December, 2001. A. (Servatrina) pectinata is dioecious and oviparous. The spawning season of this species occurred once a year from June to August, with the main spawning occurring between June and July when the seawater temperature was around $20^{\circ}C$. Ripe oocytes were about 60-65 ${\mu}m$ in diameter. The reproductive cycle of this species could be classified into five successive stages; early active stage (November to March), late active stage (February to May), ripe stage (April to July), partially spawned stage (June to August), and spent/inactive stage (August to October). Monthly changes in the gonad index reached a maximum (4.6) in May (ripe stage), thereafter, the GI values gradually decreased from June to August when spawning occurred continuously. Therefore, monthly changes in the GI values showed a similar pattern to the gonadal phase. The condition index (CI) of the meat part without the posterior adductor muscle reached the maximum in June (ripe and partially spawned stage) and the minimum in September (spent/inactive stage), Accordingly, monthly changes in the condition indice of the meat part without the posterior adductor muscle coincided with the gonadal phases.

• The Plant Pathology Journal
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• 제37권4호
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• pp.347-355
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• 2021

Ripe rot caused by Botryosphaeria dothidea is one of the serious diseases of postharvest kiwifruit. In order to control ripe rot on Actinidia chinensis cultivar 'Zesy002', several commercial agrofungicides were selected by an antifungal test on an artificial medium. Furthermore, disease suppression by the selected fungicides was evaluated on the kiwifruit by inoculation with a conidial suspension of B. dothidea. On the artificial media containing boscalid + fludioxonil was shown to be the most effective antifungal activity. However, in the bio-test pyraclostrobin + boscalid and iminoctadinetris were the most effective agrochemicals on the fruit. On the other hand, the infection structures of B. dothidea on kiwifruit treated with pyraclostrobin + boscalid were observed with a fluorescent microscope. Most of the fungal conidia had not germinated on the kiwifruit treated with the agrochemicals whereas on the untreated fruit the fungal conidia had mostly germinated. Electron microscopy of the fine structures showed morphological changes to the conidia and branch of hyphae on the kiwifruit pre-treated with pyraclostrobin + boscalid, indicating its suppression effect on fungal growth. Based on this observation, it is suggested that ripe rot by B. dothidea may be suppressed through the inhibition of conidial germination on the kiwifruit treated with the agrochemicals.

• The Plant Pathology Journal
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• 제24권3호
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• pp.269-278
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• 2008

Ripe rot was frequently observed on fruits, leaves and stems of grape growing in eight locations in Korea from 2004 to 2006. All 30 isolates of Colletotrichum sp. were obtained from lesions of the ripe rot on grape plants. Out of the isolates, 19 isolates were identified as Colletotrichum acutatum and the others as Colletotrichum gloeosporioides based on morphological and cultural characteristics. Inter and intra specific variations of the Colletotrichum spp. isolates were investigated using RAPD and sequences of rDNA ITS and $\beta$-tubulin-2. Isolates of C. acutatum and C. gloeosporioides were distinctly differentiated by molecular analyses. Phylogenetic trees of ITS and$\beta$-tubulin-2 showed that Korean isolates of C. acutatum were clustered into groups A2 and A3 among the eight global groups. A2 included non-chromogenic isolates and A3 chromogenic ones. Both C. acutatum and C. gloeosporioides isolates were tested for pathogenicity to grape leaves. All isolates tested induced lesions on the leaves of grape by artificial inoculation. There was no difference in pathogenicity between C. acutatum and C. gloeosporioides isolates. This is the first report that C. acutatum except C. gloeosporioides causes grape ripe rot in Korea.