• 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.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.297-302
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• 2020

Root-knot nematodes (Meloidogyne spp.) are the most destructive group of plant-parasitic nematodes. Plants infected by Meloidogyne spp. develop above-ground symptoms, stunting, yellowing, nutrient deficiencies, and gall formations with typical hook-shaped root tips. Infected plants experience yield losses. During 2018-2019 survey, leaf chlorosis rice plants were found in 206 fields of 67 counties in Guangxi, China, around 30 days after transplanting. Galls and hooked tips on the roots and pear-shaped females were observed. About 32.04% of fields were infested with the nematode. The nematodes were identified as Meloidogyne graminicola base on morphological and molecular analysis. To the best of our knowledge, this is the first report of M. graminicola on rice plants in Guangxi, China. The results of this study urge the discovery of resistant cultivars and the development of management strategies.

• Korean journal of applied entomology
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• v.28 no.3
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• pp.120-145
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• 1989

The nematodes associated with rice in Korea were investigated at 1,160 rice paddies in 387 localities during the last 3 years since 1985. As the result, 35 nematode species were found associated with rice in Korea. Among them 26 species were newly reported from rice in Korea; and 15 species, Criconemoides informis, Criconemella paragoodeyi, Criconema (Criconema) jaejuense, Ditylenchus longicauda, Eutylenchus africanus, Merlinius n. sp., Meiodorus n. sp., Ogma(Homogma) serrata, Ogma(Homogma) insulicum, Orientylus orientalis, Paratylenchus lepidus, Pararotylenchus pini, Triversus n. sp., Tylenchorhynchus clavicaudatus, Tylenchorhynchus nudus were firstly added for the world as associated with rice. Criconemella paragoodeyi, Merlinius n. sp., and Ditylenchus longicauda were distributed all over the country with high population density, and expected as potentially important rice parasitic nematodes. Hirschmanniella imamuri was distributed all over the country with high population density. Hirschmanniella oryzae was also distributed along with Hirschmanniella imamuri in the southern part of the country, but gradully disapeared as it goes to the northern part.

• Korean journal of applied entomology
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• v.21 no.1 s.50
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• pp.8-14
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• 1982

Distribution and population of plant parasitc nematodes were investigated using 70 soil and root samples in total collected from six locations in Gyeongbug and Gyeongnam provinces. Among nematodes identified, Meloidogyne spp. was the most prevalent with $91.4\%$ in frequency cf detection. Frequency of detection was $87.1\%$ for Tylenchus sp., $24.3\%$ for Hirschmanniella, $23.3\%$ for Aphelenchus sp., and $20\%$ for Aphelenchoides sp.. Meloidogyne spp. was most abundant from samples collected in Namji and the number of nematodes dectected was 2,104 per $300cm^3$ soil. The number of Meloidogyne spp. detected was 671 from Milyang, 401 from Samrangjin. The number of nematodes was 57 from Samrangjin for Tylenchus sp., 127 from Gupo for Pratylenchus, 26 for Aphelenchoides sp. and 34 for Criconemoides from Samrangjin. Population of Meloidogyne spp. was the highest in Namji and Milyang where pepper and cucumber or pepper and chinese cabbage was cultivated in multiple croppings, however, population of Pratylenchus spp., and Meloidogyne spp. was the highest in Samrangjin where strawberry was cultivated as a single crop. Population in Pratylenchus and Meloidogyne was the highest in Gupo where tomato and chinese cabbage were cultivated alternatively, however, population of nematodes was generally low in Seongju and Yucheon where watermelon-rice or pepper-rice were cultivated in sequence. Meloidogyne spp. and Pratylenchus spp. appear to be economically important nematode species in cropping by controlled horticulture. In this study, 15 species of plant parasitic nematodes were identified.

• Korean journal of applied entomology
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• v.4
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• pp.67-74
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• 1965

The work on the 'Studies of radiosensitivity' in Korea has been initiated since 1959 by the author at various institutions in home and foreign countries, and more than 20000 of plant materials in 73 varieties and 41 kinds are treated under varied conditions for the studies of radiosensitivity in plants. However, a study of the susceptibility to radiation in insect pests as well as their biological effects has not been previously reported in this country. During the year of 1964 and 1965, near 50000 of insects at the stages of adult, egg, larva and pupa in 14 different kinds are irradiated under acute X and gamma rays to investigate the behavior of growth and lethality after irradiation, and thrir general tolerances to radiations are compared by the kind of insects, stage of growth, radiation sources and exposured dosages. Through the experiments, it is shown that the lethality in most of insects are high as several kilo roentgens above and no significant effects on pupation. emergence, and oviposition in the treated generation at the dose of 3 Kr. below, but in the following generation , the rice stem borer for instance, no oviposition or decreased laying is observed from the dosages at 3 Kr. to 1 Kr., and the hatching was possible from 1.5 Kr. below of irradiated larvae although laying and hatching are seemed in normal. In general, the lethal dose $50\%$ of tested infect materials at the larval stage can he classified some what 60-80 Kr. for Pine caterpillar, Fall webworm, Camphor silk moth and their relatives, at 40-60 Kr. for Gypsy moth, Monley prominent and some relatives and at 20-30 Kr. for House fly, Rice weevil, Pine sawfly etc. Plant parasitic nematodes such as Hirschmannia and Paratylenchus shown very high resistance to radiation and the LD-50 is observed from 100 Kr. or above. A concept to evaluate the radiosensitivity in insects by taxological family line as a practical measure is not answerable yet, but it ran he solved within the near future through the continuing experiments.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.396-415
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• 1992

To investigate identification of species distribution state, population density of plant parasitic nematodes and damaged state by parasitism of nematodes with soil samples taken from major cultivating area of medicinal herbs in Kyungbuk districts are summarized as follow; total species belonging to genera in families were identified from 43 different medicinal herbs. The dominant nematode species on medicinal herbs was Meloidogyne hapla by 55.6% of field infection. Damaged state by parasitizm of Root-knot nematode, M. hapla, M. incognita are severed 15 medical plant except P. japonica, infected field were in 54.5~88.0%, and highered in population densities of 2nd larvae, Gall, Egg sac. Percentage of yield-decrease were 57.8% in A. gigas, 49.1% in P.japonica. Lighten effect of M. spp. by cropping system were lowered in population density in Rice+Paeony than Paeony+Paeony in paddy field, and also lowered in Sesame+Paeony or one year fallowing after harvest Paeony than Red pepper+Pseony, Paeony+Paeony in upland field.