• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1199-1206
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• 2021

Accordingly, attention is also being paid to the agricultural use of remote sensing technique that non-destructively and continuously detects the growth and physiological status of crops. However, when remote sensing techniques are used for crop monitoring, it is possible to continuously monitor the abnormality of crops in real time. For this, standard growth information of crops is required and relative growth considering the cultivation environment must be identified. With the relationship between GDD (Growing Degree Days), which is the cumulative temperature related to crop growth obtained from ideal cultivation management, and the vegetation index as standard growth information, compared with the vegetation index observed with the spectralreflectance sensor(SRS_NDVI & SRS_PRI) in each rice paddy treated with standard cultivation management and non-fertilized, it was quantitatively identified as a time series. In the future, it is necessary to accumulate a database targeting various climatic conditions and varieties in the standard cultivation management area to establish a more reliable standard growth information.

• Journal of Ecology and Environment
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• v.31 no.2
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• pp.115-123
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• 2008

We describe plant biomass in the grasslands of the Mongolian steppe obtained using a quadrat sampling technique. Four sites were studied in the northeastern Mongolia located between $47^{\circ}12'N$ and $47^{\circ}40'N$ and $102^{\circ}22'E$ and $112^{\circ}24'E$, which were typical grasslands of the steppe. Biomass, carbon and nitrogen content were determined for the plants collected from the grazed and ungarazed stands. With the measurements above, we expect to obtain information on grazing effects on the grasslands and carbon sequestration of the grassland from the air. In order to estimate the biomass without destroying the stands, we derived an equation to describe the relationship between plant biomass and v-value using plant height and species coverage within the stand. Estimated plant biomass in the ungrazed and grazed stands ranged between $108.0\;g\;m^{-2}$ and $13.4\;g\;m^{-2}$ and between $97.5\;g\;m^{-2}$ and $14.1\;g\;m^{-2}$ in late June 2005, respectively. Litter in the ungrazed and grazed stands ranged from $330.3\;g\;m^{-2}$ to $78.4\;g\;m^{-2}$ and from $188.0\;g\;m^{-2}$ to $20.3\;g\;m^{-2}$, similarly. Average carbon and nitrogen contents in plants and in litter were 43.0% and 1.9% and 33.7% and 1.4%, respectively. In study sites at Baganuur, the carbon and nitrogen content of plant materials (plant plus litter) was $118.4\;g\;m^{-2}$ and $4.7\;g\;m^{-2}$ on 30 June 2005.

• Molecules and Cells
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• v.42 no.7
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• pp.503-511
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• 2019

As sessile organisms, plants have developed sophisticated system to defend themselves against microbial attack. Since plants do not have specialized immune cells, all plant cells appear to have the innate ability to recognize pathogens and turn on an appropriate defense response. The plant innate immune system has two major branches: PAMPs (pathogen associated molecular patterns)-triggered immunity (PTI) and effector-triggered immunity (ETI). The ability to discriminate between self and non-self is a fundamental feature of living organisms, and it is a prerequisite for the activation of plant defenses specific to microbial infection. Arabidopsis cells express receptors that detect extracellular molecules or structures of the microbes, which are called collectively PAMPs and activate PTI. However, nucleotidebinding site leucine-rich repeats (NB-LRR) proteins mediated ETI is induced by direct or indirect recognition of effector molecules encoded by avr genes. In Arabidopsis, plasmamembrane localized multifunctional protein RIN4 (RPM1-interacting protein 4) plays important role in both PTI and ETI. Previous studies have suggested that RIN4 functions as a negative regulator of PTI. In addition, many different bacterial effector proteins modify RIN4 to destabilize plant immunity and several NB-LRR proteins, including RPM1 (resistance to Pseudomonas syringae pv. maculicola 1), RPS2 (resistance to P. syringae 2) guard RIN4. This review summarizes the current studies that have described signaling mechanism of RIN4 function, modification of RIN4 by bacterial effectors and different interacting partner of RIN4 in defense related pathway. In addition, the emerging role of the RIN4 in plant physiology and intercellular signaling as it presents in exosomes will be discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.6
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• pp.862-879
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• 2001

The walls of all higher plants are organized as a cellulosic, fibrillar phase embedded in a matrix phase composed of non-cellulosic polysaccharides, some proteins and, in most secondary walls, lignin. At the effective utilization of plant biomass, qualitative and quantitative analyses of plant cell walls are essential. Structural features of individual components are being clarified using newly developed equipments and techniques. However, "empirical" procedures to elucidate plant cell walls, which are not due to scientific definition of components, are still applied in some fields. These procedures may give misunderstanding for the effective utilization of plant biomass. In addition, interesting the investigation of wall organization is moving towards not only qualitatively characterisation, but also quantitation of the associations between wall components. These involve polysaccharide-polysaccharide and polysaccharide-lignin cross-links. Investigation of the associations is being done in order to understand the chemical structure, organization and biosynthesis of the cell wall and physiology of the plants. Procedures for qualitative and quantitative analyses based on the definition of cell wall components are reviewed focussing in nutritional elucidation of forage grasses by ruminant microorganisms.

• Journal of Plant Biotechnology
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• v.3 no.2
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• pp.67-81
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• 2001

Traditionally, genetic variability is generated by an extensive crossing program, which is complemented by strict selection to identify useful new recombinants. Plant biotechnology offers many opportunities for breeders to solve certain breeding problems at the molecular level. The tissue culture methodology and the genetic modification of economically important monocotyledons have undergone a revolution in the last decade. As the production of transgenic plants is a complex procedure, including the uptake of DNA molecules into the cells, the integration of foreign nucleotide sequences into the host genomic DNA and the expression of new genes in a controlled way, and as there are still many unsolved questions, further development is necessary. The methodology opens up the possibility of introducing novel genes that may induce resistance to diseases and abiotic stresses, allow the modification of dough quality and the dietetic quality of proteins, and increase the levels of micronutrients such as iron, zinc, and vitamins. In the present review, the authors would like to summarise the most important advances in wheat transformation.

• Journal of Forest and Environmental Science
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• v.37 no.2
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• pp.148-153
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• 2021

This study was carried out to establish in vitro propagation system influenced by plant growth regulators through organogenesis with three different seed sources (China, Mongolia and Russia) for conservation of genetic resources in Northeast Asia. The experiment compared two different carbon sources (commercial sugar, sucrose), which showed no significant differences in germination rate. Induced adventitious buds from leaf segments were found to be highly effective when supplemented with 1.0 mg/L BA, 1.0 mg/L Kinetin, and 5.0 mg/L IAA, in the case of Chinese origin 96.8%, Russian origin R-1: 95.6%, R-2: 85.6%, and Mongolian origin M-2: 77.8%. It was effective in BA and Kinetin with supplemented with IAA, respectively. Shooting development was also efficient in Woody Plant Media (WPM) supplemented with 1.0 mg/L BA, 1.0 mg/L Kinetin and 5.0 mg/L IAA.

• Research in Plant Disease
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• v.9 no.2
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• pp.57-63
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• 2003

Clubroot disease of curcifer crops caused by Plasmodiophora brassicae had been first reported in 1928 in Korea, and maintained mild occurrence until 1980s. Since 1990s the disease has become severe in alpine areas of Kyonggi and Kangwon, gradually spread to plain fields throughout the country, and remains as the great-est limiting factor for its production. Researches on the disease has begun in late 1990s after experiencing severe epidemics. Survey of occurrence and etiological studies have been carried out, particularly, on the pathogen physiology, race identification, quantification of soil pathogen population, and host spectrum of the pathogen. Ecology of gall formation and its decay, yield loss assessment associated with time of infection, and relationships between crop rotation and the disease incidence was also studied during late 1990s. In studies of its control, more than 200 crucifer cultivars were evaluated for their resistance to the disease. Lime applica-tion to field soil was also attempted to reduce the disease incidence. Resistant radish and welsh onion were recommended as rotation crops with crucifers after 3-year field experiments. However, so for, most studies on clubroot disease in Korea have been focused on chemical control. Two fungicides, fluazinam and flusulfamide, were selected and extensively studied on their application technologies and combination effects with lime application or other soil treatment. To develop environmentally-friendly control methods, solar-disinfection of soil, phosphoric acid as a nontoxic compound, and root-parasiting endophytes as biocontrol agents were examined for their effects on the disease in fields. In the future, more researches are needed to be done on development of resistant varieties effective to several races of the pathogen, establishment of economically-sound crop rotation system, and improvement of soil-disinfection technique applicable to Korean field condi-tion, and development of methodology of pretreatment of fungicides onto seeds and seedbeds.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.281-287
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• 2013

In Korea, isolated cultivation has been implemented for 102 genera, including about 250 species, each of which has underwent microscopic inspection, cultivation of bacteria in selective medium, analysis of physiology and biochemistry, enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). The number of isolated microorganisms was 8,307 in the period of 2005-2012, and bulbs and tubers had the greatest diversity of microorganisms, of 5,165 (62.2%), followed by 2,119 (25.0%) sapling, 796 (9.6%) seed, 150 (1.8%) cutting slip, 70 (0.8%) branch graft and 7 (0.1%). The number of cases which were disqualified were 413 (4.97%), after the detection of 47 disease causing species of microorganism. Viruses predominated, with 27 species, followed by 16 fungi, a viroid, a Chromalveolata and 2 further species. Top on the list of detection was Arabis mosaic virus (77 cases), followed by Tobacco rattle virus (70 cases), Lily symptomless virus (46 cases) and Penicillium expansum (46 cases).

• The Plant Pathology Journal
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• v.35 no.2
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• pp.112-124
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• 2019

Barley worldwide is affected seriously by Fusarium seedling blight (FSB) and Fusarium head blight (FHB) diseases caused by the Fusarium species. The objective of this study was to facilitate the resistance of hulled and hull-less barley at different growth stages to F. culmorum according to direct parameters: disease rating (DR), fresh weight of leaves and roots, kernel weight per spike, kernel number per spike, plump kernels, and indirect parameters - chlorophyll a fluorescence (CF). Plate assay, greenhouse and field tests were performed on 30 spring barley doubled haploid (DH) lines and their parents infected with Fusarium culmorum. Direct parameters proved that hulled genotypes show less symptoms. Most studied chlorophyll a fluorescence (CF) parameters (apart from DIo/CS - amount of energy dissipated from PSII for laboratory test, TRo/CS - amount of excitation energy trapped in PSII reaction centers, ETo/CS - amount of energy used for electron transport and RC/CS - number of active reaction centres in the state of fully reduced PSII reaction center in field experiment) were significantly affected by F. culmorum infection. In all experiments, hulled genotypes had higher values of CF parameters compared to hull-less ones. Significant correlations were detected between direct and indirect parameters and also between various environments. It was revealed that ABS/CS, TRo/CS, and RC/CS have significant positive correlation in greenhouse test and field experiment. Significant correlations suggest the possibility of applying the CF parameters in selection of barley DH lines resistant to F. culmorum infection.

• Journal of Forest and Environmental Science
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• v.40 no.1
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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.