• The Plant Pathology Journal
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• v.27 no.4
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• pp.360-366
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• 2011

Bacterial leaf spot of Euphorbia pulcherrima has been reported in many countries. Characterization by polyphasic approaches indicated that the isolates from India, USA and New Zealand could be distinguished based on rep-PCR profiles and gyrB phylogenies, while the Chinese isolates should be ascribed to Xanthomonas axonopodis pv. poinsettiicola.

• Korean journal of applied entomology
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• v.31 no.3
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• pp.256-275
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• 1992

Insects are among the most important abiotic and biotic constraints to rice production. National rice research programs are in various stages in the development and implementation of integrated pest management (IPM) stratagies for rice insect control. Among the various control tactics, insect resistant cultivars are sought as the major tactic in rice IPM. Through the activities of interdisciplinary teams of scientists significant progress has been made in the development and release of insect resistant cultivars to farmers. Because of its compatibility with other control tactics insect resistance has proven to fit well into the IPM approach to rice insect control agents and minimize the need for insecticide applications. The development of biotypes which overcome the resistance in rice plants has been a significant constraint in the breeding of rice for resistance to insects. Most notable examples in Asia are the green leafhopper, Nephotettix virescens, brown planthopper, Nilaparvata lygens and the Asian rice gall midge, Orseolia oryzae. The current breeding stratege is to develop rice cultivars with durable resistance on which virulent biotypes cannot adapt. In spite of the significant progress made in the breeding of insect resistant cultivars there are still numerous important rice insect species for which host plant resistance as a control tactic has not been fully utilized. Advances in biotechnology provide promise of solving some of the problems that have limited the use of host plant resistance as a major tactic in the integrated management of rice insect pests.

• The Plant Pathology Journal
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• v.25 no.4
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• pp.429-432
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• 2009

An unreported disease of apricot was observed in orchards in Zhejiang province, China. Symptoms started as water soaked lesions on the fruit surface. Later, water-soaked areas developed and spread to the entire fruit, resulting in soft rot of the whole fruit. The causal organism isolated from symptomatic fruits was identified as Burkholderia cepacia based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 16S rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto fruits of apricot. In addition, European plum, Japanese plum, nectarine and kiwifruit were susceptible to the B. cepacia pathogen. However, the B. cepacia pathogen failed to cause any visible symptoms when it was inoculated onto 16 other fruits. This is the first report of a bacterial disease of apricot caused by B. cepacia in China.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.5 no.1
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• pp.21-27
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• 2024

Harmful pet insects, if not controlled, can negatively affect people, plants and their surrounding environment. In Vietnam, all crops are regularly impacted by pest insects. In serious cases, crops can be totally destroyed by insect pests. Harmful insects that damage crops often grow fast and increase rapidly. Therefore, research on insects is crucial for managing pests, protecting crops, and forecasting pest situation in the following years. This study aimed to collect data regarding changes of pests on rice and corn as two main crops in four provinces in Red River Delta of Vietnam, including Thai Binh, Nam Dinh, Ha Nam, and Hung Yen, from 2018 to 2022. Primary data were collected from reports of government agencies and official statistics. Based on these data, this study evaluated changes of pest insects in five years, discussed reasons for such changes and response methods, and forecasted pest's behavior in the following years. Significant findings of this study include the fact that Vietnam has to face many difficulties to develop its agricultural sector. For insect management, an essential action is to do ground surveys to gather all related data including weather data, pesticide data, crop yield, and product quality. This information is meaningful for finding out causes of changes, understanding relationships between insects and surrounding factors, and predicting the situation in the following years.

• Korean Journal of Agricultural Science
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• v.45 no.1
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• pp.28-37
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• 2018

This study was done to develop environmental risk assessments and a biosafety guide for insect-resistant genetically modified rice at a LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-9) resistant to Cnaphalocrocis medinalis and on non-GM rices (Dongjin and Ilmi) were investigated. The Bt-9 event was therefore evaluated under field conditions to detect possible impacts on the above ground insects and spiders. The study compared transgenic rice and two non-GM reference rices, Ilmi and Dongjin, at Gunwi in Southern Korea in 2016. Each rice was grown on three $18m^2$ plots with a randomized block design. A total of 4,243 individuals from 43 families and 9 orders were collected from the LMO isolation field. In the three types of rice fields, a total of 1,467 individuals from the insect-resistant genetically modified rice (Bt-9), 1,423 individuals from the Ilmi, and 1,353 individuals from the Dongjin were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies and other insects on the insect-resistant genetically modified rice (Bt-9) and non-GM rices. These results provide the diversity and population density of non-target insects for an environment risk assessment survey on insect-resistant genetically modified rice and could be used as a guideline to make a biosafety assessment method for genetically modified crops.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.91-94
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• 2009

An unreported disease of garlic was observed in commercial fields in Jiangsu province, China. The symptoms started as water soaked lesions at the base of the leaves. Later, water-soaked areas developed on stems and spread to the internal tissues, followed by yellowing and necrosis along leaf edges and soft rot of the stems. The causal organism isolated from symptomatic plants was identified as Pseudomonas fluorescens based on its biochemical and physiological characteristics and confirmed by the cellular fatty acid composition and Biolog data as well as 168 rRNA gene sequence analysis. The bacterial isolates caused similar symptoms when inoculated onto garlic plants. In addition, leek and shallot were susceptible to the P. fluorescens pathogen. However, the P. fluorescens pathogen failed to cause any symptoms when it was inoculated onto 15 other plants. This is the first report of a bacterial disease of garlic caused by P. fluorescens in China.

• The Plant Pathology Journal
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• v.26 no.2
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• pp.189-193
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• 2010

The in vitro antibacterial properties of two kinds of chitosan solutions and their effect in protection of broccoli from bacterial head rot disease were evaluated. Results showed that the two kinds of chitosan solution at different concentrations exhibited strong antibacterial activity against Pseudomonas fluorescens. However, the antibacterial activity of chitosan A solution increased with the increase of chitosan concentration up to 0.10 mg/ml while the antibacterial activity of chitosan B solution increased with the increase of chitosan concentration up to 0.05 mg/ml. In addition, the antibacterial activity of chitosan A and chitosan B solution of 0.10 mg/ml increased with the incubation time within 12 h and 24 h, respectively. The disease incidence and the lesion diameter of broccoli inoculated with P. fluorescens were significantly reduced when plants were either pretreated or post-treated with six different combinations of chitosan solutions. Overall, the results indicated that the two kinds of chitosan solutions had a potential in controlling bacterial head rot of broccoli.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.223-230
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• 2010

The Burkholderia cepacia complex isolates causing bacterial fruit rot of apricot were characterized by speciesspecific PCR tests, recA-HaeIII restriction fragment length polymorphism (RFLP) assays, rep-PCR genomic fingerprinting, recA gene sequencing, and multilocus sequence typing (MLST) analysis. Results indicated that the isolates Bca 0901 and Bca 0902 gave positive amplifications with primers specific for B. vietnamiensis while the two bacterial isolates showed different recA-RFLP and rep-PCR profiles from those of B. vietnamiensis strains. In addition, the two bacterial isolates had a higher proteolytic activity compared with that of the non-pathogenic B. vietnamiensis strains while no cblA and esmR marker genes were detected for the two bacterial isolates and B. vietnamiensis strains. The two bacterial isolates were identified as Burkholderia seminalis based on recA gene sequence analysis and MLST analysis. Overall, this is the first characterization of B. seminalis that cause bacterial fruit rot of apricot.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.140.2-141
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• 2003

Among over-wintering small brown planthoppers, population of the rice stripe virus (RSV)-viruliferous insects was surveyed throughout the country in late April of 2003 by using DAS-ELISA. Averaged population of the RSV-viruliferous insects in this year was 2.1％, which was lower than that of last year of 3.7％. However, the insect population in Seoul, Incheon and Kyeonggi areas were relatively high showing 6.7％, 6.2％ and 2.6％, respectively. Based on the survey results, it was expected that overall occurrence of RSV on rice could be decreased in this year, except certain areas. Ovarial transmission rate of RSV by the insects on diseased rice samples collected from 10 areas ranged from 22.2％ to 77.8％. Among 35 graminous weed species collected from rice fields in Ganghwa and Kimpo in 2002 and 2003, common reed and formosens were found to be infected by RSV. The result indicates that those weeds are potential alternative natural hosts of the RSV Further studies on ecological and pathological impacts of the alternative natural host of RSV are being processed.

• Korean Journal of Organic Agriculture
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• v.6 no.2
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• pp.75-80
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• 1998

Organically cultured rice fields were surveyed to compare the population density and the structure of microarthropod communities between chemically controlled and un-controlled fields. In rice fields, microarthropod communities were also compared among four treatments based on different input of fertilzer : 1)No fertilizer, 2)Chemical fertilizer(N-P2O5-K2O = 11 - 7 - 8 kg/10a, 3) Compost (5,000kg/10a), 4) Compost com-plemented with chemical N. Richness index of microarthropod communities in rice fields was greater in the chemically uncontrolled field than controlled field. Within field. the compost plot had greater value of richness index for microarthopod commuities than the non-fertilizer polt. A total of 9 aquatic insects species were identified in the water of organic farming rice field the population density was found to be higher in the compost plot than the other plot. The population of insect pests was found to be high in the late stage of plant whereas the population of insects was high in the early stage of rice plant.