Syngonium podophyllum Schott plants are increasingly being imported in Korea due to their ability to purify indoor air. Root lesion nematodes, Pratylenchus spp., are the most frequently occurring nematodes associated with S. podophyllum, leading to the disposal of plants or their return to the country of origin, due to inadequate phytosanitary treatments. We evaluated the effectiveness of hot water treatment in controlling Pratylenchus penetrans Cobb, present in S. podophyllum and Perilla frutescens Britton. The mortality rate (LT_99%: the time at which 99% lethality is achieved) of P. penetrans at 44 to 52 °C water and treatment-caused plant damage were evaluated in vitro and in vivo. The in vitro test showed the LT₉₉ at 44, 46, 48, 50, and 52 °C was 119.1, 27.0, 14.70, 1.40, and 0.48 min, respectively. The LT₉₉ of hot water treatment on the nematodes infecting both plants was 18.4 to 1.7 min at 46 to 50 °C. S. podophyllum was undamaged at 30 days after treatment with 49 and 51 °C water for 30 min. This study demonstrates that hot water treatment is a potential phytosanitary disinfection method for Pratylenchus spp. infecting foliage plants, which can accelerate their trade by reducing incidents of disposal or return to the country of origin.

In East Asia, especially in South Korea, Perilla frutescens L. is widely cultivated for food and industrial uses. Root-lesion nematodes, particularly Pratylenchus penetrans Cobb, are significant pests in Korean perilla fields, leading to chlorosis, root necrosis, and decreased yields. This study examined the effectiveness of hot-water treatment for controlling P. penetrans in P. frutescens under large-scale conditions at two different temperatures and durations. Additionally, because ornamental plants are often a main route for the international spread of quarantine plant-parasitic nematodes, two commonly traded ornamental species (Syngonium podophyllum L. and Schefflera arboricola L.) were examined alongside P. frutescens to assess how hot water treatment affected their health by measuring weight, chlorophyll content, and root length. Results indicated that the relative reduction in P. penetrans recovery was 99.66% at 48 °C for 20 min and 99.98% at 50 °C for 3 min. While some thermal damage was observed in P. frutescens following both treatments, exposing the plants to 50 °C for 3 min did not significantly affect the quality of S. podophyllum and S. arboricola. These results highlight that hot water treatment effectively controls plant-parasitic nematodes and maintains ornamental plant quality, which could aid in developing quarantine protocols for traded planting materials.