• Journal of Korean Society for Quality Management
• /
• v.48 no.4
• /
• pp.581-596
• /
• 2020

Purpose: purpose of this study was to propose the web application platform which can be to detect and discriminate various diseases and pest of tomato plant based on the large amount of disease image data observed in the facility or the open field. Methods: The deep learning algorithms uesed at the web applivation platform are consisted as the combining form of Faster R-CNN with the pre-trained convolution neural network (CNN) models such as SSD_mobilenet v1, Inception v2, Resnet50 and Resnet101 models. To evaluate the superiority of the newly proposed web application platform, we collected 850 images of four diseases such as Bacterial cankers, Late blight, Leaf miners, and Powdery mildew that occur the most frequent in tomato plants. Of these, 750 were used to learn the algorithm, and the remaining 100 images were used to evaluate the algorithm. Results: From the experiments, the deep learning algorithm combining Faster R-CNN with SSD_mobilnet v1, Inception v2, Resnet50, and Restnet101 showed detection accuracy of 31.0%, 87.7%, 84.4%, and 90.8% respectively. Finally, we constructed a web application platform that can detect and discriminate various tomato deseases using best deep learning algorithm. If farmers uploaded image captured by their digital cameras such as smart phone camera or DSLR (Digital Single Lens Reflex) camera, then they can receive an information for detection, identification and disease control about captured tomato disease through the proposed web application platform. Conclusion: Incheon Port needs to act actively paying.

• Korean journal of applied entomology
• /
• v.21 no.3 s.52
• /
• pp.153-158
• /
• 1982

The study was conducted to obtain the basic information on the diseases epidemics of vegetable crops grown in Namji, Jinju, Gimhae and Suncheon under the extremely varied and specified conditions, plastic film house. The disease survey was conducted from the end of April, 1951 to April 1982. Leaf mold and late blight were serious foliar disease in tomato during the seedling stage, especially when the infected seeds were sown. The diseases increased rapidly 35 days after seeding. In both continuous cultivation of cucumber and rotation with upland crops, incidence of Fusarium wilt was severe while incidence of the disease was negligible in cultivations after paddy rice or grafting on pumpkin. Downy mildew of cucumber was severe in Jinju and Suncheon area, however, it was not so serious in Namji area where the growing season of cucumber was unfavorable for the maximum disease incidence. Cucumber mosaic virus disease was prevalent in the areas surveyed and the disease incidence was increased rapidly after June. Powdery mildew prevailed at the early stage of cucumber growth after transplanting in Namji area. Root rot and wilting caused by Phytophthora capsici was as the most destructive disease in pepper grown under the vinyl house, especially in Namji and Jinju area where the pepper has been cultivated intensively. The Phytophthora attacked most parts of young plants during the winter time and then induced crown rot on the adults plants. Cultivation of pepper in vinyl house was almost impossible because of the Phytophora disease by the end of June. Virus diseases to tomato plants were prevalent throughout the surveyed area and the damage was also severe. In Jinju and Gimhae area leaf mold and late blight showed high infection rate in tomato during the harvest time.

• The Korean Journal of Pesticide Science
• /
• v.10 no.4
• /
• pp.359-366
• /
• 2006

The protective effect of kresoxim-methyl was investigated on 6 important plant diseases, and the vapour effect of it did on barley and cucumber powdery mildews, respectively. With 2.0 ${\mu}g\;mL^{-1}$ of kresoxim-methyl, its high activities against wheat leaf rust and barley powdery mildew were showed such as 92 and 100%, while activities were very low against rice sheath blight, tomato gray mold, and tomato late blight. In vapour phase control activity of kresoxim-methyl against barley powdery mildew was positively correlated with the applied concentrations, except for azoxystrobin and metominostrobin. With 200 ${\mu}g\;L^{-1}$, its control value was 71.9%. When 1000 ${\mu}g\;m^{-3}$ of kresoxim-methyl in vapour phase was applied on 4 plants of cucumber in a vinyl chamber, 51.1% of control value on kresoxim-methyl-treated cucumber was showed 7 days after the application.

• The Plant Pathology Journal
• /
• v.26 no.4
• /
• pp.360-366
• /
• 2010

In the course of a searhing environmental friendly antifungal compounds, we found that mixture of methyl esters of fatty acids obtained from soybean oil had potent control efficacy against barley powdery mildew (Blumeria graminis f. sp. hordei). In this study, ten alkyl fatty acid esters (AFAEs) were tested for in vivo antifungal activity against five plant diseases such as rice blast, rice sheath blight, tomato gray mold, tomato late blight and barley powdery mildew. Some AFAEs showed the most control efficacy against barley powdery mildew among the tested plant diseases. By 5-hr protective and 1-day curative applications, six AFAEs ($3,000\;{\mu}g/ml$), including methyl and ethyl palmitates, methyl and ethyl oleates, methyl linoleate, and methyl linolenate demonstrated both curative and protective activities against barley powdery mildew. In contrary, methyl laurate strongly controlled the development of powdery mildew on barley plants by curative treatment at a concentration of $333\;{\mu}g/ml$, but did not show protective activity even at $3,000\;{\mu}g/ml$. Under greenhouse conditions, the seven AFAEs ($1,000\;{\mu}g/ml$) except for methyl and ethyl stearates, and methyl caprylate also effectively controlled cucumber powdery mildew caused by Podosphaera xanthii. Among them, methyl and ethyl palmitates ($333\;{\mu}g/ml$) represented the most control activity of more than 68% against the disease. The results are the first report on the antifungal activity of methyl and ethyl esters of fatty acids against plant pathogenic fungi.

• The Korean Journal of Pesticide Science
• /
• v.5 no.3
• /
• pp.26-35
• /
• 2001

In order to search potent antifungal substances from domestic plants, 40 plants cultivated in Korea were collected. After extracting with methanol (MeOH) and concentrating to dryness, the MeOH extracts were screened for in vivo antifungal activity against six plant diseases at a concentration of $2000{\mu}g/mL$. Fourteen extracts showed disease-controlling activity more than 90% against at least one of the 6 plant diseases tested; eight, seven, and three extracts controlled more than 90% the development of rice blast, tomato late blight, and wheat leaf rust, respectively. However, none of the extracts exhibited in vivo antifungal activity more than 90% against rice sheath blight, tomato gray mold, and barley powdery mildew. From the MeOH extracts of Angelica gigas and A. dahurica showing potent controlling activity against rice blast, 1 and 2 antifungal substances, respectively, were isolated by solvent partitioning and column chromatography. The three compounds were identified to be coumarins, namely, decursin, imperatorin, and isoimperatorin, by mass spectrometry and NMR spectroscopy. They were examined for in vitro and in vivo antifungal activities together with umbelliferone (7-bydroxycournarin) and scopoletin (6-methoxy-7-hydroxycoumarin) containing a free hydroxyl group at position 7 to investigate the structure-activity relationship. In vitro, most of 50% growth inhibitory concentrations ($IC_{50}$) were over $200{\mu}g/mL$, indicating that they have relatively weak antifungal activity. The antifungal activity of decursin and scopoletin, containing cyclic alkoxy groups instead of free hydroxyl group at position 7, was stronger than umbelliferone and scopoletin. Especially, decursin and imperatorin showed potent antifungal activities against Pythium ultimum and Magnaporthe grisea, respectively, with $IC_{50}$ values less than $25{\mu}g/mL$. In vivo, decursin and imperatorin showed potent antifungal activity against rice blast, whereas other coumarins hardly controlled the development of 6 plant diseases tested. These results suggest that the antifungal activity of 7-hydroxycoumarin derivative is substantially increased when the hydroxyl group at position 7 is protected by a stable cyclic alkoxy grouping.

• Korean Journal of Agricultural Science
• /
• v.39 no.4
• /
• pp.583-589
• /
• 2012

In the continued research on natural fungicides for the control of plant diseases by using plant-derived products, we found that Reynoutria elliptica. had a strong fungicidal activity against several plant pathogens. R. elliptica (3.2 kg) were extracted with 80% aq. MeOH and the concentrated extracted was partitioned with n-hexane, EtOAc, n-BuOH and $H_2O$ successively. The four layers were tested their disease control efficacies against 4 plant disease such as rise blast (RCB), tomato grey mold (TGM), tomato late blight (TLB), and barly powdery mildew (BPM). The n-hexane fraction was highly active showing over 95% control against TLB and BPM. and the EtOAc fraction was highly active showing over 95% control against RCB, TLB, and BPM. By using silica gel chromatography, MPLC, and HPLC, three compounds that were expected to have antifungal activity were isolated. Their chemical structures were elucidated as physcion, emodin, and emodie-8-O-glucoside by EI-MS and NMR spectroscopic analyses.

• Horticultural Science & Technology
• /
• v.30 no.5
• /
• pp.557-567
• /
• 2012

This study was conducted to achieve basal information for the development of tomato cultivars with disease resistances through marker-assisted backcross (MAB). Ten inbred lines with TYLCV, late blight, bacterial wilt, or powdery mildew resistance and four adapted inbred lines with superior horticultural traits were collected, which can be useful as the donor parents and recurrent parents in MAB, respectively. Inbred lines collected were evaluated by molecular markers and bioassay for confirming their disease resistances. To develop DNA markers for selecting recurrent parent genome (background selection) in MAB, a total of 108 simple sequence repeat (SSR) primer sets (nine per chromosome at average) were selected from the tomato reference genetic maps posted on SOL Genomics Network. Genetic similarity and relationships among the inbred lines were assessed using a total of 303 polymorphic SSR markers. Similarity coefficient ranged from 0.33 to 0.80; the highest similarity coefficient (0.80) was found between bacterial wilt-resistant donor lines '10BA333' and '10BA424', and the lowest (0.33) between a late blight resistant-wild species L3708 (S. pimpinelliforium L.) and '10BA424'. UPGMA analysis grouped the inbred lines into three clusters based on the similarity coefficient 0.58. Most of the donor lines of the same resistance were closely related, indicating the possibility that these lines were developed using a common resistance source. Parent combinations (donor parent ${\times}$ recurrent parent) showing appropriate levels of genetic distance and SSR marker polymorphism for MAB were selected based on the dendrogram. These combinations included 'TYR1' ${\times}$ 'RPL1' for TYLCV, '10BA333' or '10BA424' ${\times}$ 'RPL2' for bacterial wilt, and 'KNU12' ${\times}$ 'AV107-4' or 'RPL2' for powdery mildew. For late blight, the wild species resistant line 'L3708' was distantly related to all recurrent parental lines, and a suitable parent combination for MAB was 'L3708' ${\times}$ 'AV107-4', which showed a similarity coefficient of 0.41 and 45 polymorphic SSR markers.

• Microbiology and Biotechnology Letters
• /
• v.30 no.2
• /
• pp.162-166
• /
• 2002

Two bithiazole-type antibiotics were isolated from the culture broth of a Myxococcus species which isolated from the marine sediment off the coast of Cheju Island, Korea. The structures of these metabolites were determined as KR025 and melithiazole F, previously reported bithiazoles, using combined spectroscopic methods. Both compounds showed an antifungal activity. In in vivo tests, these compounds exhibited potent controlling activities against tomato late blight, wheat leaf rust, and barley powdery mildew with control values more than 80% at a concentraton of 20 $\mu\textrm{g}$/ml.

• The Korean Journal of Pesticide Science
• /
• v.10 no.2
• /
• pp.149-152
• /
• 2006

Construction of focused library of 2-benzylimino-1,3-thiazolines 7 through molecular modification of 3-alkyl-2-phenylimino-1,3-thiazolines 1 which showed selective fungicidal activity against rice blast and their fungitoxic activity against 6 kinds of typical plant diseases was described. Fifty four compounds of focused library of 2-benzylimino-1,3-thiazolines 7 were synthesized from the reaction of the corresponding $\gamma$-chloroacetoacetanilides 6 with N-benzyl thioureas 5 by parallel synthetic methodology. As results of fungicidal screening against the typical plant diseases, twenty eight kinds of 7 at 100 ${\mu}g$ $mL^{-1}$ showed the control value over 50% against tomato late blight.

• The Korean Journal of Pesticide Science
• /
• v.6 no.2
• /
• pp.87-95
• /
• 2002

Disease control activities of the methanol extracts from 27 plant species were investigated against six plant diseases such as rice blast, rice sheath blight, tomato gray mold, tomato late blight, wheat leaf rust and barley powdery mildew. The extracts of Humulus japonicus, Hosta longipes, Liriope platyphylla, and Astragalus membranaceus exhibited a great in vivo control activity against rice blast. Similarly, the extracts of Commelina communis and A. membranaceus were highly active on tomato gray mold and barley powdery mildew, respectively. The extracts of H. longipes, L. platyphylla, Solanum nigrum and A. membranaceus showed especially high disease control activity against wheat leaf rust, and then were selected for further tests such as protective, curative, systemic, and lasting activity against wheat leaf rust. The extracts of L. platyphylla and S. nigrum were strong protectant, and that of A. membranaceus possessed both a preventive activity and a curative activity. Systemic disease control by the selected four plant extracts was investigated by examing translaminar activity from leaf-under-surface to leaf-upper-surface and systemic activity by leaf-to-Ieaf movement. All extracts strongly controlled wheat leaf rust by translaminar movement, but hardly controlled the disease by leaf-to-leaf movement. Good lasting activity was also observed against wheat leaf rust from all of the tested extracts. Especially, disease control experiments on wheat seedlings sprayed with the extracts of S. nigrum or H. longipes 7 days prior to inoculation represented control value over 95%. These results suggest that methanol extracts of H. longipes, L. platyphylla, S. nigrum, and A. membranaceus, especially S. nigrum, would potently control wheat leaf rust caused by Puccinia recondita in the fields.