Survey of overwintering sites of R. pedestris in diverse landscapes in Korea

다국어 초록 (Multilingual Abstract)

R. pedestris is a major insect pest in agricultural production, especially on soybean and tree fruit, in Korea. Currently, the management of this pest relies mainly on insecticide application in most commodities. However, the chemical controls cause numerous environmental problems. To develop sustainable management tools, it is fundamental to understand the basic biology and ecology of R. pedestris. However, the overwintering ecology of this pest is virtually unknown. In this study, we surveyed diverse landscapes including high elevation mountains soybean fields and there neighboring forests to find and characterize the overwintering sites of R. pedestris. In the field, we sampled leaf litters from 1㎡ grids to locate overwintering R. pedestris. The samples were taken every 100m altitude in the mountain areas or every 50m distance in the flat landscapes. Overwintering R. pedestris were found from 6 samples out of 137 samples. All overwintering R. pedestris were located from forested areas adjacent to urban landscapes in Seong-Nam si, Gyeong-Gi Do. Interestingly, no overwintering R. pedestris was found from in the samples collected from high elivation mountains including Yeon-In, Song-Ni, Chi-Ak, Ga-Ya, Wol-Chul. likewise, no overwintering individual was found from soybean fields and their neighboring forested areas. With caveat that the data were collected only for 1 year, our results support that R. pedestris overwinters solitary resulting in low detection rates from the samples. Given that R. pedestris typically disperse into cultivated crops with high densities, it is important to better understand environmental factors affecting the presence or absence of overwintering R. pedestrris in diverse landscapes. The knowledge would be essential to develop sustainable monitoring and management programs for this economically important pest in Korea.