점박이응애(Tetranychus urticae)에 대한 살비활성을 가지는 물질을 알아보기 위하여 약용식물 25과 35 종의 메탄올 또는 헥산 추출물을 이용하여 잎 침지법과 살포법으로 실내와 pot, 야외에서 실험을 수행하였 다. 살비활성은 약용식물 종류별로 차이를 보였다. 강남콩(Phaseolus vulgaris var. humilis) 잎을 1,000 ppm 농도의 추출물에 1분간 침지한 후 점박이응애에 대한 치사율을 조사한 결과, 비자나무(Torreya nucifera) 열매 추출물과 팥꽃나무(Daphne genkwa)와 도꼬마리(Xanthium strumarium), 나팔꽃 (Pharbitis nil) 씨앗 추출물이 각각 56.8%와 47.8, 47.7, 47.7%의 살비활성을 나타내었다. 잎 침지시간을 30초로 단축시켜 점박이응애에 대한 살비효과검정 시는 1분 침지에 비하여 효과가 감소하였고, 나팔꽃과 도꼬마리의 살비 활성이 가장 높았다. 도꼬마리와 나팔꽃 씨앗 헥산 추출물의 반수치사농도는 각각 1,824 ppm과 1,899 ppm이었다. 두 식물의 1,000 ppm 온수 및 냉수 추출물은 점박이응애에 대한 살비효과가 20% 이하로 낮았다. Pot의 강낭콩에 점박이응애를 접종한 후 분무법으로 추출물을 1,000 ppm 농도로 살포한 결과 도꼬마리와 나팔꽃 씨앗 헥산추출물은 각각 76.3과 71.3%의 높은 살비활성을 나타내었다. 그리고 온실에서 국화의 점박이응애를 대상으로 나팔꽃 씨앗 헥산 추출물을 2,000 ppm과 1,000 ppm으로 처리 시에 는 50.8%와 35.1%의 방제가를 보였다.

An ambrosia beetle, Platypus koryoensis, is a vector of Raffaelea quercimongolicae that is known to cause Korean Oak Wilt (KOW), one of the serious threats to forest healthy in Korea. To manage P. koryoensis properly, it is necessary to clarify flight period of the adult. This experiment was conducted to elucidate the relationship between temperature and the flight period based on field observation in three forests consisted of Quercus mongolica from 2007 to 2009 except winter season. Date of flight period for 50% (FP50) was estimated by the cumulative Weibull distribution model based on cumulative proportion of the adult density and air temperature. Relationship between site temperature and the date of FP50 of P. koryoensis was the most significant when temperatures below 6.5℃ were excluded, suggesting lower threshold temperature for the flight period based on the site temperature. The pooling cumulative proportion of flight period against degree days was well described by the degree-day model, which has explanatory power for the 89% of year and site variation in the flight period and predicted accurately the flight pattern in 2011.

Spatio-temporal distribution pattern of an ambrosia beetle, Platypus koryoensis (Murayama) which is vector of Raffaeleaquerci-mongolicae K.H. Kim et al, a causative agent for Korean oak wilt (KOW) was examined in the stand level. Spatial distribution of P. koryoensiswas influenced by their density. Relationship between degree of aggregation and density was positively correlated when the density was extremely low or high whereas the relationship was reverse when the density was intermediate. Patch of P. koryoensis formed around or near dead trees or partial dead trees, suggesting these trees indicated epicenter of P. koryoensis. Fraction of trees attacked by less than 100 individual of P. koryoensis in the stand per year increased abruptly whereas fraction of trees attacked over 1,000 individuals of P. koryoensis increased gradually. Our results showed that the dead trees would be an epicenter of P. koryoensis and the number of trees killed by the ambrosia beetle would be reduced by lowering total population of the ambrosia beetle around the epicenter.

Trapping efficiency by trap types, colors and positions in the trunk was evaluated for monitoring and the integrated pest management of Playtpus koryoensis, known as a vector of Korean oak wilt disease. The experiments were conducted in oak forest located in Gwangtan-myeon, Paju-si, Gyeonggi-do, Korea using two types of trap: sticky trap and multi-funnel trap. Trapping efficiency of two trap types was not significantly different. Trapping efficiency of the sticky trap was not affected by four trap colors: yellow, black, white and transparent. The number of caught by the traps, regardless of trap types, was higher in the traps facing upper slope than lower slope.

An ambrosia beetle, Platypus koryoensis, is known as a major vector of Korean oak wilt disease (KOW) to Mongolian oak and it is considered as the one of the major threat to forest ecosystem health. This study was conducted to assess damage on Mongolian oak inflicted by the ambrosia beetle on the basis of entry hole density and location within the trunk. Two hundred forty Momgolian oak trees from Mt. Uam (Gyonggi-Do, Korea) and 60 from Mt. Gyebang (Gangwon-Do, Korea) were randomly selected. Initially, the damage degree on an individual tree and the diameter at breast height (DBH) were measured, and followed by the measurement of entry hole density per 148 X 210 mm2 on lower trunk (above the surface of the earth) and upper (100 cm above the surface) on each upslope and downslope. The damage degrees were divided into three classes: Ⅰ indicating healthy tree, Ⅱ tree damaged by the ambrosia beetles and Ⅲ dead tree by the KOW. As the damage class of the Mongolian oaks increased, the number of the entry holes increased regardless of locations of entry holes. The density of entry hole lower trunk was higher than that in upper trunk, showing that the ambrosia beetle preferred to attack the lower trunk on downslope. In addition, the results showed a tendency that the average DBH of the oak trees increased as the damage class increased from Ⅰ to Ⅲ. This suggests that the ambrosia beetle prefers to attack older trees. The entry hole densities on each lower and upper trunk on downslope were principal components to assess the damage degrees of the Mongolian oak.

The first occurrence of oak wilt disease(OWD) in Korea was reported in 2004 and a Platypodid beetle, Platypus koryoensis, was known to contribute significantly the occurrence of the disease. To reduce the oak wilt disease, it is necessary to control density of P. koryoensis under injury level. This experiment conducted to clarify the flying period of adult P. koryoensis. Four forests containing dead trees by OWD were selected and the location of the experimental sites were Mt. Surak in Seoul, Goyang-si, Paju-si in Gyeonggi-do, Hongcheon-gun in Gangwon-do. Sticky trap or vertical multi-funnel trap was settled on Quercus mongolica trees located in infested forest. Density of P. koryoensis was survey with one or two week interval from May to October in 2007 and 2008. The number of the beetle collected by the vertical trap and sticky trap was positively correlated (r2=0.69). The optimum flying period of the beetle was ranged from late June to late July with geographical variations.