• Journal of Life Science
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• v.10 no.4
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• pp.403-407
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• 2000

For the biological control of the root-lesion nematodes, Pratylenchus spp., which damage directly and indirectly to the leaf perilla, the nematical effect of three nematode-trapping fungi, Arthrobotrys oligospora, A. conoides and A. dactyloides was evaluated in the field. Three species of Arthrobotrys were isolated from the culture soil of leaf perilla in 1998 and were observed the capture of the root-lesion nematodes, Pratylenchus spp. by adhesive hyphal networks or constricting rings on agar. At 40 days after treatment, the plant-parasitic nematodes and root-lesion nematode populations were approximately increased 3.5 fold in untreated control plot, while the nematode population in fungi treatment plots was similar to initial population. In the A. dactyloides plot, however, the population of plant-parasitic nematodes and Pratylenchus spp. was approximately reduced 65% and 53%, respectively. Thus, the fungus A. dachyloides should provide as biological agent for the control of Pratylenchus spp.

• Korean journal of applied entomology
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• v.53 no.1
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• pp.51-57
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• 2014

We identified the five root-lesion nematode species, Pratylenchus crenatus, P. fallax, P. kumamotoensis, P. panamaensis and P. penetrans from intercepted in quarantine inspection over the past five years. Their diagnostic characters are including number of lip annuli, stylet length, shape of the labial region, presence or absence of males, structure of lateral fields, shape of spermatheca, length of the post-vulval uterine sac and shape of tail and so forth. We described the photos, measurements and morphological characters.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.112-119
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• 1995

Anatomical and biochemical changes of the corn root injured by the root lesion nematode, Pratylenchus vulnus, were examined to understand the interactions between the nematode and the crop which can be applied to a breeding program for nematode-resistant crop. The nematode and the crop which can be applied to be a breeding program for nematode-resistant crop. The nematode entered the cortex of corn root through its epidemis. They moved to other cortical cells by breaking their cell walls. They, finally, gathered around the endodermis of the roots and the bases of the root hairs. Parasitism of the nematode formed cavities within the root tissues where the females laid eggs. Major root damage by the nematode occurred in the cortical cells where must cell walls were broken and crushed to form empty spaces. These empty spaces in the base of the root resulted in this breakdown. Damage-induced biochemical changes of the corn roots were analysed by their total protein patterns and esterase activities in both control and nematode-infected roots. Denaturing gel did not show any significant difference in the banding patterns between them. Esterase patterns and activities, also, were not significantly different between the infected and the control roots.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.146-152
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• 1982

Survey on potato parasitic nematodes has been undertaken in order to find distribution of the nemic fauna. 41 soil samples were taken from potato fields in Gyeongbug, Gyeongnam and Gangweon provinces. Twenty four species belonging to 16 different genera were identified. Potato cyst nematode, Globodera rostochiensis was not found in the areas. Potato-rot nematode, Ditylenchus destructor and stem nematode, Ditylenchus dipsaci were found from several potato fields and population density high and showed damage to the crops. Root-lesion nematode, Pratylenchus minyus, Pratylenchus penetrans, Pratytenchus thornei and Pratylenchus vulnus were found and their population of these four species were high depending on the fields. Root-knot nematode, Meloidogyne hapla and Meloidogyne incognita were found. M. hapla was found only in Gangweon province and the population density was high. M. incognita was found at Milyang in Gyeongnam province. Spiral nematode, Heticotylenchus digonichus, Helicotylenchus dihystera, Helicotylenchus pseudorobustus, Rotylenchus orientalis and Rotylenchus pini were found. Aphelenchoides saprophilus, Criconemoides informis, Ditylenchus destructor, D. dipsaci, Helicotylenchus digonichus, H. dihystera, Hemicriconemoides intermedius, Meloidogyne hapla, Psilenchus hilarulus, Pratylenchus minyus, and Xiphinema americanum were first found from potato fields in Korea.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.501-512
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• 2019

To survey the incidence of plant-parasitic nematodes, 187 soil samples from leguminous plant fields in Chungnam province, Korea were assessed from June to August 2018. As the result, four nematode genera - the cyst nematode (Heterodera spp.), root-knot nematode (Meloidogyne spp.), root-lesion nematode (Pratylenchus spp.), spiral nematode (Helicotylenchus spp.) - were detected. Among them, the incidence of cyst nematode was the highest in Taean (73%) and lowest in Hongseong (10%). The cyst nematode was detected from the adzuki and kidney bean fields as well as soybean fields. The incidence of cyst nematode in upland fields was higher than in paddy fields. In addition, the extracted cyst nematodes consisted of two species, which was identified as Heterodera glycines and H. sojae. The incidence of H. glycines (22%) was higher than H. sojae (10%), and a few of the fields (5%) was mixed with two cyst nematodes. This result suggested that we should consider that the cyst nematode is the major plantparasitic nematode when controlling the nematodes in soybean fields in Chungnam province.

• Korean Journal of Organic Agriculture
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• v.30 no.1
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• pp.103-118
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• 2022

Photorhabdus is a bacterial symbiont of entomopathogenic nematodes of the genus Heterorhabditis in the family Heterorhabditidae. Photorhabdus is known to have nematicidal activity in addition to insecticidal activity. P. temperata isolated from Korean indigenous H. megidis Gwangju strain also produced high control efficacy against root-knot nematode Meloidogyne incognita and root-lesion nematode Pratylenchus penetrans. P. temperata has drawn interest as a potential bionematicide for the control of root-knot nematodes thereby. For the registration as an organic agricultural material, the toxicity of P. temperata was assessed by the acute toxicity test in carp (Cyprinus carpio) and acute oral and dermal toxicity tests in Sprague-Dawley rat (Rattus norvegicus) in compliance with the guidelines of the Rural Development Administration (RDA). In the acute toxicity test in fish, neither lethality nor abnormal responses of carp were observed. Body length and weight of carp and changes in DO concentrations and pH values were not significantly different between the treated group and the untreated control. In the acute oral and dermal toxicity tests, clinical signs, abnormal behavior, mortality, and pathological findings were not observed in all the experimental rats. The weight increment of all rats was normal. Acute toxicity results of P. temperata in fish and rats belonged to categories III, IV, and IV of RDA, respectively. Toxicity results of the present study indicated that P. temperata could be a safe and promising bionematicide against root-knot nematodes and root lesion nematode.

• Research in Plant Disease
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• v.25 no.3
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• pp.124-130
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• 2019

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on Chinese yam (Dioscorea batatas) in Andong, Korea. Root-knot nematodes, Meloidogyne incognita was the most prevalent nematode species which is found from 43 yam fields (81.1%) with high population densities (average of 450 juveniles/$300cm^3$). Other nematodes, root-lesion nematode (Pratylenchus spp.) and pin nematode (Paratylenchus spp.) were less problematic. Density of juveniles (J2) of M. incognita was $10\;J2/300cm^3$ by August, then increased to 274 in September and 624 in October. The highest J2 density was found at the soil depth between 40 and 50 cm ($1,840\;J2/300cm^3$). M. incognita was able to infest yam tuber down to a depth of 70 cm and developed galls outside and brown spots inside. The highest number of females were found at 40-50 cm (79 females/10 cm piece) tuber from the top.

• Research in Plant Disease
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• v.29 no.4
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• pp.459-463
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• 2023

This study was conducted to investigate the plant-parasitic nematodes of ornamental foliage plants, citrus orchards, and tea plantations from July to December 2022. As a result of the investigation of plant-parasitic nematodes in 415 foliage plants, root-lesion nematodes were detected most frequently, followed by root-knot nematodes, pin nematodes, and other nematodes. In tea plantations, spiral nematodes, cyst nematodes, and root-knot nematodes were detected. Citrus nematodes, ring nematodes, and root-knot nematodes were discovered in citrus orchards. In foliage plants, tea plantations, and citrus orchards, the detection rate of plant-parasitic nematodes was not high, but root-lesion nematodes were detected. Therefore, it is necessary to apply appropriate control methods to manage root-lesion nematodes during the cultivation of foliage, tea, and citrus plants.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.473-478
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• 2008

Root-lesion nematode (Pratylenchus vulnus) and pin nematode (Paratylenchus sp.) were detected with high population density at the spray chrysanthemum greenhouse in Gumi, Gyeongbuk. The average density of P. vulnus and Paratylenchus sp. was 667 and 716 nematodes per 100 g soil and P. vulnus density were distributed 87% to the depth of $0{\sim}30$ cm in greenhouse. When spray chrysanthemum cv Chopin, was transplanted in September 2004 in greenhouse, P. vulnus were 854 nematodes/100 g soil in planting and increased 14,985 nematodes/100 g soils and 1g root after 10 weeks in harvest. Shoot weight and shoot height of spray chrysanthemum decreased 24.8% and 8.0% compared with non-infested P. vulnus after 10 weeks in greenhouse.

• Research in Plant Disease
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• v.22 no.4
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• pp.249-256
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• 2016

To investigate the incidence of plant-parasitic nematodes from plastic-house fields of strawberry, 170 soil samples were collected from the main producing area of strawberry in Korea from 2014 to 2015. Based on the investigation, root-lesion nematode (RLN; Pratylenchus spp.) and root-knot nematode (RKN; Meloidogyne spp.) are the most important pests in plastic-house fields of strawberry with 57% and 36% incidences, respectively. Among the collected fields, 96 and 63 fields were infected RNL and RKN, respectively with 44 fields (38.8%) being detected at both nematode. High degree of incidence of both nematodes were observed in the regions of Jinju, Gyeonnam Province, Korea. For identification of species level, phylogenetic and distance analysis were performed using RLN and RKN isolates generated from the regions of Jinju. The results indicated that the RLN and RKN isolates were Pratylenchus vulnus and Meloidogyne hapla, respectively. This study showed that P. vulnus and M. hapla could be most dominant species in plastic-house fields of strawberry. This data will provide basic knowledge for development of effective control strategies.