• Korean Journal of Environmental Biology
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• v.40 no.4
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• pp.550-555
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• 2022

Perilla plant is a special crop that is used as oilseed and food in Korea. Root lesion nematodes have caused great damage to perilla plants, so for effective management of root lesion nematodes, it is necessary to understand their ecology in perilla. In this study, we investigated the effect of temperature in the development of Pratylenchus penetrans (Pp) and Pratylenchus vulnus (Pv) when the nematodes infected the perilla plant. To estimate the effect of temperature, we assessed the reproduction factor (RF); final population/initial population(Pf/Pi) of these two nematode species. We used perilla plants as inoculated hosts and investigated the density of nematodes at 10 weeks after inoculation. As a result, the RF of Pp was highest at 20℃ (0.41 (1st test), 2.2 (2nd test)) followed by 25, 30, and 15℃. The RF of Pv was highest at 30℃(9.84 (1st test), 31.39 (2nd test)), followed by 25, 20, and 15℃. Comparing the RF by temperature between Pp and Pv, Pv was higher than Pp at all temperatures used in the test. This study showed the optimal development temperature of Pp was 20-25℃ and Pv was 30℃, respectively.

• 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.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 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.

• 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.