• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.69-69
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• 2005

• Korean journal of applied entomology
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• v.27 no.3
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• pp.159-164
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• 1988

Five nematophagous fungi were evaluated for their nematicidal effect in vitro on Rhabditis sp. and Meloidogyne hapla in soil. Inocula of Arthrobotrys arthrobotryoides, A. conoides, A. oligospora, Dactylella lobata, and Fusarium oxyaporum were grown in moistened corn-sandy soil and chopped potato-sandy soil media, and incubated at 26$^{\circ}C$ for one week. The prepared inocula were incorporated in autoclaved sandy soil, mixing thoroughly at rates equ-invalent to 1:50, 1:100, 1:200, and 1:400, repectively, before 80g of the mixture carrying 100 Rhabditis sp. was put into petri plates. Nematophagous fungi effectively teduced the popuation of Rhabditis sp. in soil in a week or two following treatment of the incula at concentration of 1:50 and 1:100. The optimum was at $25^{\circ}C$ for nematicidial effect as high as 80-100%. The at the rate of 1:100 prepared incula were incorporated in auto-claved soil, where 100 Juveniles M. hapla were introduced per 80% soil. All fungi infected the M. hapla effectively in soil, caysing more than 90% mortality within one week. This result indicated the potential value of these fungi as promising biocontrol agents.

• Research in Plant Disease
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• v.23 no.2
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• pp.186-192
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• 2017

To survey the incidence of plant-parasitic nematode in strawberry nursery, 117 soil samples were collected from main producing area of strawberry nursery plants in 2016. The incidences of two major problematic nematodes such as root-lesion nematodes (Pratylenchus spp.) and root-knot nematodes (Meloidogyne spp.) were 11% and 3%, respectively. Strawberry nurseries using upland soil either in fields or in plastic-houses showed were higher infection rates of Pratylenchus spp. or Meloidogyne spp. than others. On the other hand, a strawberry nursery using pots filled with bed soil in plastic-house was the lowest infection rate with 0%. Phylogenetic relationships and distance analysis were performed for identification of Pratylenchus spp. and Meloidogyne spp. detected from strawberry nurseries. As the results, they were identified as Pratylenchus penetrans, Pratylenchus vulnus and Meloidogyne hapla. Meanwhile, when nursery plants of strawberry infested with P. vulnus transplanted to pots filled with sterilized soil, P. vulnus was detected from soil in pots as 33% frequency. Thus, P. vulnus can be spread through nursery plants of strawberry infested with that. These studies suggested that Pratylenchus spp. and Meloidogyne spp. were ploblematic nematodes in major areas of strawberry nursery plants and P. vulnus could be spread through nursery plants of strawberry.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.603-605
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• 1998

Soil and root samples were collected form the rhizoshpere of 11 different medicinal plants to determine the incidence, density and identification of root-knot nematode species associated with medicinal herbs. About 55% of medicinal herbs examined was found to be infested with root-knot nematodes. As a result of infection casued by three root-knot nematodes, M. hapla recorded 43.3% in medicinal herba whereas M. incognita and M. arenaria showed 7.9% and 3.7%, repectively. Forsythia koreana, Hemerocalis fulva, Hibuscus mutabilis and Petasites japonicus were the most severely infested herbs whereas Acanthopanax sessilflorus was least infested. Population of the second stage younger plants. Meloidogyne hapla, M. incognita and M. arenaria were the species associated with the medicinal herbs. The most abundant nematode observed in medicinal herbs was M. hapla and followed by M. incognita and M. arenaria. M. arenaria was observed firstly on Ficus carica, one of medicinal plant.

• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.251-261
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• 1983

Survey on soybean parasitic nematodes has been undertaken in order to get an ideas about the distribution of nemic fauna. Total 71 soil samples were collected from soybean fields in Gyeongbug and Chungbug provinces. Eighteen species belonging to fourteen different genera were found associated with soybean, Glycine max. The results were as follows: Aphelenchus avenae, Circonemoides informis, Ditylenchus dipsaci, Helicotylenchus pseudorobustus, Heterodera glycines, Hirschmanniella imamuri, Meloidogyne hapla, Meloidogyne incognita, Paratylenchus pandus, Pratylenchus thornei, Pratylenchus vulnus, Psilenchus hilarulus, Rotylenchus sp. Tylenchorhynchus clay toni, Tylenchorhynchus dubius, Tylenchorhynchus nudus, Tylenchus sp. Xiphinema americanum were found in soybean fields. In frequency of occurring nematodes by localities, soybean cyst nematode was higher in Chungbug by $70\%$, while $50\%$ in Gyeongbug. But rook-knot nematode was higher in Gyeongbug by $54.1\%$, while $19.1\%$ in Chungbug. In density of nematode, Heterodera was the most dominant as 200.4 populations per 100ml soil, Meloidogyne as 107.1 populations, Rotylenchus, Xiphinema, Aphelenchus in decreasing order. In survey of loss, density of soybean cyst nematode in heavily infested fields was 155 cysts per 100ml soil while 35 cysts in slightly infested fields. Seventy percent of soybean yields was decreased when comparing with average 64.2kg/10a in heavily infested fields and average 209.5kg/10a in slightly infested. Correlation coefficients among number of soybean cyst and yields, pod weight, number of pod was negative as r- 0.57, 0.47, 0.38 over all localities.

• 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.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.23-28
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• 2022

The conversion of rice-fields to uplands is increased in last 8 years due to the government's policy. To obtain basic informations on plant-parasitic nematodes in converted uplands, we surveyed nematodes associated with crops cultured on the ridge of the rice-fields. The crops mostly cultivated at the ridge of rice-field were soybean (66%), red bean (21%), and perilla (13%). Ten important plant-parasitic nematodes species were identified: Helicotylenchus sp., Heterodera glycines, Meloidogyne arenaria, M. javanica, M. hapla, Paratylenchus projectus, Pratylenchus coffeae, P. neglectus, Rotylenchus incultus, Trichodorus sp. Tylenchorhynchus crassicaudatus, and T. claytoni. Among them, Rotylenchus incultus was the most common plant-parasitic nematode in all three crops. The ridge is a border of rice field, thus plant-parasitic nematodes infested on ridges should be cautioned for future cropping.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.355-359
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• 2004

A survey was conducted during $April{\sim}May$ 2004 to determine the occurrence and population density of plant-parasitic nematodes in ginseng (Panax ginseng C.A. Meyer) growing fields, in major ginseng growing regions of Chungbuk, Chungnam, Gyeongbuk and Kyongki provinces. The survey revealed presence of eleven species of plant-parasitic nematodes namely, Criconemoides morgensis, Ditylenchus destructor, Helicotylenchus dihystera, Meloidogyne incognita, M. hapla, Paratylencgus lepidus, Pratylenchus penetrans, Psilenchus hilarulus, Trichodorus similis, Tylenchorhynchus claytoni and Xiphinema americanum. Frequency and density of each species were highly variable. M. incognita and M. hapla were the predominant species, their infestation observed in 46.3 and 39.4% fields with an average density of $78{\sim}254\;and\;76{\sim}211$ nematodes per $300\;cm^3$ soil, respectively. Whereas, T. similis and X. americanum were rarely observed; only in 2.3 and 1.8% of surveyed fields and their density was $10{\sim}17\;and\;7{\sim}10$ individuals per $300\;cm^3$ soil, respectively. They are recorded herewith for the first time from ginseng fields of Korea. In nematode-infestated fields, stunted plant growth with chlorotic leaves, and wilted plants were observed in patches.

• Korean journal of applied entomology
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• v.22 no.1 s.54
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• pp.15-20
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• 1983

Effects of the root-knot nematode, Meloidogyne hapla, on the growth and yields of hot-pepper (var.: Cheongyong gochu) and tomato$(var.:\;Bogsu\;\#)$ were studied with inoculating 500, 2,500, 5,000, 7,500, 10,000 and 20,000 nematodes per plant in pots. Results were analyzed with comparing weight of fruits harvested throughout the season from both hot-pepper and tomato, and with mineral contents in dried stoots and roots of pepper plant 20 weeks after the inoculation. No significant difference was found on the plant growth at all levels of inoculation until the 8th week after the inoculation. However, the plant growth was significantly depressed from the 12th week in the pots inoculated with over 10,000 nematodes, and the yields were reduced by $16\%$ in hot-pepper and $14\%$ in tomato respectively when 10,000 nematodes were inoculated.

• The Plant Pathology Journal
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• v.33 no.1
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• pp.66-74
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• 2017

This study was conducted to examine infectivity (penetration and gall and egg-mass formations) of the root-knot nematodes, Meloidogyne incognita and M. hapla, on carrots grown in soil conditions of 5 different soil textures consisting of bed-soil (b) and sand (s) mixtures (b-s mixtures) at the ratios of 10:0, 7:3, 5:5, 3:7, and 0:10. For M. incognita, the nematode penetration rates in b-s of 0:10 (100% sand) were significantly higher than in the other b-s mixtures, more greatly at 2 and 5 days after inoculation than at 10 DAI, while no significant differences in the penetration rates were mostly shown for M. hapla at the above DAI. However, for both nematodes, gall and egg-mass formations were remarkably increased in the b-s mixture of 0:10, compared to the other b-s mixtures, which is coincided with the general aspects of severe nematode infestations in sandy soils. This suggests the increased gall and egg-mass formations of M. incognita should be derived from the increased penetration rates in the sandy soil conditions, which provide a sufficient aeration due to coarse soil nature for the nematodes, leading to their mobility increased for the enhanced root penetration. For M. hapla, it is suggested that the sandy soil conditions affect positively on the healthy plant growth with little accumulation of the inhibitory materials and sufficient aeration, enhancing the nematode growth and feeding activities. All of these aspects provide information reliable for the development screening techniques efficient for the evaluation of the nematode resistance in the breeding programs.