• 식물병연구
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• 제18권4호
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• pp.399-401
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• 2012

발아현미 가공용 친환경 원료곡 생산에 적합한 벼 품종을 선발하기 위하여 농촌진흥청 국립식량과학원에서 개발된 주요 벼 품종을 친환경 재배단지(전남 곡성군)에서 3년간(2009-2011년) 유기재배를 실시하여 병해 및 수량 변화를 조사하였다. 삼광벼에서 벼 잎집무늬마름병과 도열병의 발병률은 대조구인 추청벼의 경우 보다 높게 나타났으나 고시히까리 보다는 현저히 낮게 발병하였다 또한 수확량은 추청벼, 고시히까리 보다 높게 나타났다. 특수미로 선발된 큰눈벼, 하이아미는 대조구인 추청벼, 고시히까리와 비슷한 발병률과 수확량을 보였다. 결론적으로 삼광벼, 큰눈벼, 하이아미는 곡성지방에서 친환경 재배를 하였을 경우 발병률 및 수량변동이 크게 변하지 않을 것으로 생각되며 특히 발아현미 원료곡으로 친환경 유기재배에 적합한 벼 품종으로서 선발 할 수 있을 것으로 판단된다.

• Journal of Forest and Environmental Science
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• 제40권1호
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• pp.1-8
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• 2024

Recently, intensive research has been conducted to develop innovative methods for diagnosing plant diseases based on hyperspectral technologies. Hyperspectral analysis is a new subject that combines optical spectroscopy and image analysis methods, which makes it possible to simultaneously evaluate both physiological and morphological parameters. Among the physiological and morphological parameters are classifying healthy and diseased plants, assessing the severity of the disease, differentiating the types of pathogens, and identifying the symptoms of biotic stresses at early stages, including during the incubation period, when the symptoms are not visible to the human eye. Plant diseases cause significant economic losses in agriculture around the world as the symptoms of diseases usually appear when the plants are infected severely. Early detection, quantification, and identification of plant diseases are crucial for the targeted application of plant protection measures in crop production. Hence, this can be done by possible applications of hyperspectral sensors and platforms on different scales for disease diagnosis. Further, the main areas of application of hyperspectral sensors in the diagnosis of plant diseases are considered, such as detection, differentiation, and identification of diseases, estimation of disease severity, and phenotyping of disease resistance of genotypes. This review provides a deeper understanding, of basic principles and implementation of hyperspectral sensors that can measure pathogen-induced changes in plant physiology. Hence, it brings together critically assessed reports and evaluations of researchers who have adopted the use of this application. This review concluded with an overview that hyperspectral sensors, as a non-invasive system of measurement can be adopted in early detection, identification, and possible solutions to farmers as it would empower prior intervention to help moderate against decrease in yield and/or total crop loss.

• 식물병연구
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• 제22권4호
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• pp.264-268
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• 2016

2014년부터 2015년까지 12개의 밭못자리 시험지에서 잎 도열병의 발병 정도를 조사하였다. 2014년 잎 도열병은 $3.7{\pm}2.1$, 2015년에는 $4.4{\pm}2.1$의 평균 발병 정도를 보였다. 특히, 2015년에는 이천과 철원에서 벼 도열병 발병률이 2014년에 비해 2배 이상 증가했다. 2014년과 2015년에 분리된 벼 도열병균 587종에 대해 한국형 판별품종 시스템으로 분석한 결과 2014년에는 34종, 2015년에는 51종의 레이스로 결정되어 병원균의 병원성 변화가 크다는 것을 알 수 있었다. KI 레이스대 KJ 레이스의비율은 2014년에는 54:46, 2015년에는 70:30으로 나타났다. 2014년의 우점 레이스는 KJ-301로 총 16%를차지했고, 2015년에는 KI-101이 15%를우점했다. 2015년 지역별 레이스 분포결과 고성에서는 KI 레이스가 97% 비율로 분포하였고, 철원에서는 KJ 레이스가 96%의 분포율을 보여 지역 간 차이가 크게 나타났다. 십여 년간 낮은 분포를 보이던 KI-101 레이스가 전국적으로 높은 비율로 확인된다는 점은, 이런 현상이 계속된다고 가정할 때, 도열병균 집단이 빠르게 변하고 있으며 이에 대한 대응이 필요하다는 것을 말해준다. 따라서 이 연구결과는 벼 도열병의 대발생을 막기 위한 벼 품종육성에 기초자료로 이용할 수 있다.

• 식물병연구
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• 제29권4호
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• pp.440-444
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• 2023

2021년 8월 부산광역시 강서구에서 아주까리의 잎과 줄기에 점무늬병의 발생이 확인되었다. 아주까리 분리균은 tryptic soy agar에서 점액성이 없고 연한 녹색을 띠는 둥근 콜로니를 형성하였다. 세균은 단극성으로 다수의 편모를 가진 막대 모양이었다. 세균을 건전한 아주까리 유묘에 접종했을 때, 동일한 점무늬 증상의 괴사 반응이 나타났다. 병징이 나타난 부위에서 세균을 재분리하여 동일균 여부를 확인하였다. 분리균은 감자 무름 반응과 D-fucose 대사반응이 양성이었으며, troleandomycin에서 생장할 수 있었다. 16S rRNA와 항존유전자(gyrB, rpoD) 염기서열의 상동성을 비교하였을때, Pseudomonas capsici와 유연관계가 가장 높았다. 결과적으로 아주까리에서 분리된 균은 배양적, 생화학적, 유전적 특성에 의해 P. capsici로 동정되었다. 본 연구는 국내 아주까리에서 P. capsici에 의한 점무늬병의 최초 보고이다.

• 한국작물학회지
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• 제35권1호
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• pp.97-107
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• 1990

The epidemiology of plant disease deals with the dynamic processes of host-pathogen interactions, which determine the prevalence and severity of the disease. Epidemic processes for most foliar diseases of plants follow a series of steps: arrival of pathogens on plant surfaces, initial infection, incubation period, latent period, sporulation, dissemination of secondary inoculum, and infectious period. These complex biological processes are influenced by the environment-Man also often interfers with these processes by altering the host and pathogen populations and the environment. Slowing or halting any of the epidemic processes can delay the development of the epidemic, so that serious losses in yield due to disease do not occur. It is generally recognized that the most effective and efficient method of minimizing disease damage is through the use of resistant cultivars, particularly when other methods such as fungicide applications are not economically feasible-Populations of plant pathogens are not genetically uniform nor are they necessarily stable. Cultivars bred for resistance to current populations of a pathogen may not be resistant in the future due to selection pressures placed on the pathogen populations. Understanding population development and genetic variability in the pathogen, and knowledge of the genetics of resistance in the plant should help in developing breeding strategies that wi1l provide effective and stable disease control through genetic resistance. In the United States, soybeans have ranked first in value of crops sold off the farm in recent years. Soybeans have been the leading U. S.

• The Plant Pathology Journal
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• 제39권4호
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• pp.319-334
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• 2023

Plant disease is an important factor affecting crop yield. With various types and complex conditions, plant diseases cause serious economic losses, as well as modern agriculture constraints. Hence, rapid, accurate, and early identification of crop diseases is of great significance. Recent developments in deep learning, especially convolutional neural network (CNN), have shown impressive performance in plant disease classification. However, most of the existing datasets for plant disease classification are a single background environment rather than a real field environment. In addition, the classification can only obtain the category of a single disease and fail to obtain the location of multiple different diseases, which limits the practical application. Therefore, the object detection method based on CNN can overcome these shortcomings and has broad application prospects. In this study, an annotated apple leaf disease dataset in a real field environment was first constructed to compensate for the lack of existing datasets. Moreover, the Faster R-CNN and YOLOv3 architectures were trained to detect apple leaf diseases in our dataset. Finally, comparative experiments were conducted and a variety of evaluation indicators were analyzed. The experimental results demonstrate that deep learning algorithms represented by YOLOv3 and Faster R-CNN are feasible for plant disease detection and have their own strong points and weaknesses.

• 식물병연구
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• 제24권4호
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• pp.339-341
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• 2018

Amaranth has the potential for good materials related to nutrients and health benefits. There are several diseases of amaranth such as leaf blight, damping-off, and root rot. As a causal agent of soft rot disease, Pectobacterium spp. could infect various plant species. In this study, we isolated the bacterial pathogen causing soft rot of amaranth in South Korea. In Gangneung, Gangwon province during 2017, amaranth plants showed typical soft rot symptoms such as wilting, defoliation and odd smell. To isolate pathogen, the macerated tissues of contaminated amaranth were spread onto LB agar plates and purified by a single colony subculture. One ml bacterial suspension of a representative isolate was injected to the stem of five seedlings of 2-week-old amaranth with a needle. Ten mM magnesium sulfate solution was used as a negative control. 16S rDNA gene and recA gene were sequenced and compared with the reference sequences using the BLAST. In the phylogenetic tree based on 16S rDNA gene and recA gene, GSA1 strain was grouped in Pcb.

• 식물병연구
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• 제19권3호
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• pp.177-182
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• 2013

Resvestrol has been known to inhibit bacterial and fungal growth in vitro, and can be accumulated in plant to concentrations necessary to inhibit microbial pathogens. Hence, stilbene synthase gene has been used to transform to synthesize resveratrol in heterologous plant species to enhance resistance against pathogens. In the present study, we investigated the antimicrobial activities of resveratrol and piceid to bacterial and fungal pathogens, which causing severe damages to rice plants. In addition, disease resistance was compared between transgenic rice varieties, Iksan 515 and Iksan 526 transformed with stlibene synthase gene and non-transgenic rice varieties, Dongjin and Nampyeong. Minimum inhibitory concentration of resveratrol for Burkolderia glumae was 437.5 ${\mu}M$, and the mycelial growth of Biplaris oryzae was slightly inhibited at concentration of 10 ${\mu}M$. However, other bacterial and fungal pathogens are not inhibited by resveratrol and piceid. The expression of the stilbene synthase gene in Iksan 515 and Iksan 526 did not significantly enhanced resistance against bacterial grain rot, bacterial leaf blight, sheath blight, and leaf blight. This study is the first report on the effect of resveratrol and piceid against pathogens of rice plant, and changes of disease resistance of transgenic rice plants transformed with stilbene synthase gene.

• The Plant Pathology Journal
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• 제38권3호
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• pp.212-219
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• 2022

Fusarium root rot caused by the soil-borne fungus Fusarium solani is one of the most important fungal diseases of cassava in Thailand, resulting in high yield losses of more than 80%. This study aimed to investigate if the exogenous application of salicylic acid formulations (Zacha) can induce resistance in cassava against Fusarium root rot and observe the biochemical changes in induced cassava leaf tissues through synchrotron radiation based on Fourier-transform infrared (SR-FTIR) microspectroscopy. We demonstrated that the application of Zacha11 prototype formulations could induce resistance against Fusarium root rot in cassava. The in vitro experimental results showed that Zacha11 prototype formulations inhibited the growth of F. solani at approximately 34.83%. Furthermore, a significant reduction in the disease severity of Fusarium root rot disease at 60 days after challenge inoculation was observed in cassava plants treated with Zacha11 at a concentration of 500 ppm (9.0%). Population densities of F. solani were determined at 7 days after inoculation. Treatment of the Zacha11 at a concentration of 500 ppm resulted in reduced populations compared with the distilled water control and differences among treatment means at each assay date. Moreover, the SR-FTIR spectral changes of Zacha11-treated epidermal tissues of leaves had higher integral areas of lipids, lignins, and pectins (1,770-1,700/cm), amide I (1,700-1,600/cm), amide II (1,600-1,500/cm), hemicellulose, lignin (1,300-1,200/cm), and cellulose (1,155/cm). Therefore, alteration in defensive carbohydrates, lipids, and proteins contributed to generate barriers against Fusarium invasion in cassava roots, leading to lower the root rot disease severity.

• 농업과학연구
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• 제50권2호
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• pp.241-247
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• 2023

Erwinia amylovora , which causes fire blight disease on apple and pear trees, is one of the most important phytopathogens because of its devastating impact. Currently, the only way to effectively control fire blight disease is through the use of antibiotics such as streptomycin, kasugamycin, or oxytetracycline. However, problems with the occurrence of resistant strains due to the overuse of antibiotics are constantly being raised. It is therefore necessary to develop novel disease control methods through an advanced understanding of the pathogenesis mechanism of E. amylovora . To better understand the pathogenesis of E. amylovora , we investigated unknown virulence factors by random mutagenesis and screening. Random mutants were generated by Tn5 transposon insertion, and the pathogenicity of the mutants was assessed by inoculation of the mutants on apple fruitlets. A total of 17 avirulent mutants were found through screening of 960 random mutants. Among them, 14 mutants were already reported as non-pathogenic strains, while three mutants, TS3128_M2899 (ΔSUFU ), TS3128_M2939 (ΔwcaG ), and TS3128_M3747 (ΔrecB ), were not reported. Further study of the association between E. amylovora pathogenicity and these 3 novel genes may provide new insight into the development of control methods for fire blight disease.