Locust gall midge (LGM), Obolodiplosis robiniae (Haldeman) (Diptera: Cecidomyiidae), is a cecidomyiid insect forming roll-up galls on leaves of Robinia pseudoacacia Linnaeus (Fabaceae). LGM, known as native to North America, was reported from Korea and Japan in 2002. LGM was observed weekly or biweekly to clarify their voltinism and distribution within the crown of the host tree in two sites of Osan and Siheung in Korea from May to August, 2007. Density of LGM was investigated based on the number of larvae per leaf. Two generations of LGM were observed in Siheung site whereas three generations in Osan site during the present study. The result indicated that LGM had at maximum three generations per year. The density of LGM in Osan was higher in the upper crown of the host trees than middle or lower part. In Siheung, LGMs were distributed more on the exterior of the lower crown than the interior. The average number of larvae per gall was 3.3±0.1 and 2.8±0.1 individuals per leaf in Osan and Siheung, respectively.

아까시잎혹파리의 형태, 생태적 특성 및 몇 가지 살충제의 살충활성을 조사하였다. 알은 길쭉한 타원형으로 연한 노란색을 띄다가 부화할 시기가 가까울수록 붉은색이 되며, 장경은 0.4 mm, 단경은 0.1 mm 이었다. 유충은 유백색을 띠고, 평균 크기는 2.6 mm 이었다. 번데기는 붉은 기운을 띈 갈색이며 체장은 3.2 mm 내외이었다. 성충의 날개는 검고 배 부분은 붉은색을 띠었다. 암컷의 체장은 3.3 mm 내외로 수컷보다 컸다. 1화기 성충은 땅속에서 우화하여 아까시나무 어린 잎에 산란을 하고, 2화기 성충부터는 아까시나무 잎의 벌레 혹에서 바로 우화한다. 암컷 성충의 포란수는 192.3±50.7개 이었다. 1화기는 4월말부터 5월말, 2화기는 5월 말부터 6월 말까지로 약 1개월간 이었고 최성기는 6월 상순이었다. 3화기는 6월 말부터 7월 말까지였다. 알기생봉인 Platygaster robiniae가 동정되었으며, 기생율은 51.6%에 이르렀다. 살충활성을 검정한 결과, 침투이행성 약제인 이미다클로로프리드 10% 수화제와 치아클로프리드 10% 액상수화제가 높은 살충활성을 나타내었으며, 특히 치아클로프리드는 꿀벌에 대한 독성이 낮아 유효한 약제로 판단되었다.

Biological Characteristic of Obolodiplosis robiniae and insecticidal activity of some insecticides against larvae of O. robiniae were investigated. Egg was in oval shape, and its color was light orange and became red when close to hatch. Length of the major axis and the minor axis of egg was 0.4 ㎜ and 0.1 ㎜, respectively. Larval color was milky and size was 2.6 ㎜. Pupa was deep brown and its size was about 3.2 ㎜. Wing and abdomen of adult was black and reddish, respectively. Size of female adult was about 3.3 ㎜, and larger than male adult. Number of eggs in the ovary was 192.3±50.7. First emergence was from late April to late May, and second from late May to late June. Third emergence was from late June to late July. Newly emerged adult escaped from soil, and second and third emerged adult escaped directly from gall of Robinia pseudoacacia leaf. Egg parasitoid was identified as Platygaster robiniae and parasite rate was 51.6%. Among test insecticides, imidacloprid 10% WP and thiacoprid 10% FL showed very strong insecticidal activity against larvae of O. robiniae at 48h later after treatment.

This study was carried out to clarify the biologies and morphological characteristics of Rhynchaenus sanguinipes. Also some chemicals were tested to screen the effective insecticide for the control of the species. Up to date, Zelkova serrata has been known as host plant of Rhynchaenus sanguinipes, which shows serious damage in this country. In the present study, Ulmus pumila was first found as host plant in this study. Body lengths of larvae, pupa and adult were 4.53±0.30 ㎜, 3.30±0.42 ㎜ and 2.96±0.12 ㎜, respectively. The overwintered adult of the species emerged on early April to late April, and adult of next generation emerged on early May to late May. Pupal periods were 10, 7.2, 5.1 and 4 days on 16, 20, 24 and 28℃, respectively. The lower developmental threshold temperature was 5.8℃. Four braconid parasitoids were found as natural enemies, which emerged mainly on late April to early June. Insecticidal activities with treatments of fenitrothion 50% EC, indoxacarb 30% WG, ethofenprox 20% EC and thiacloprid 10% SC was investigated against adult of R. sanguinpes, and they showed ＞90% mortality.

밤나무혹벌 산란동아수의 품종별 차이를 비교한 결과, 석추 및 다압에서 가장 적었고 전체적으로 신초의 하부로 갈수록 산란동아수가 많았으며 특히, 옥광, 축파, 유마 에서 이러한 현상이 뚜렷하였다. 대부분의 품종에서 동아당 평균 1.0개 이상 다중 산란되었으며 신초하부의 경우 산란수가 재래종, 축파, 옥광, 평기에서는 3.0개 이상이었으며 석추와 다압은 1.0개 미만이었다. 산란동아별 난수는 모든 품종에서 상부의 동아에 산란된 난수가 가장 적었고, 하부의 동아에 많은 경향을 보였다. 신초하부의 경우 축파는 산란된 알이 평균 15개 이상으로 가장 많았던 반면, 다압은 한개 이하로 가장 적었다. 품종별 산란비율은 모든 품종에서 밤나무혹벌이 산란한 동아를 발견 할 수 있었으며, 재래종이 로 가장 높았고, 축파와 유마에서는 각각 78.5와 이상의 산란율을 나타내었다.

This study was carried out to analyze conceptional structure between visitor's satisfaction and loyalty in the national natural recreation forests. The results of this study showed that facility, natural resources and view, staff service of recreation forest had positive effect on visitor's satisfaction. Reservation system, accessibility, and usage fee of recreation forest was not related to visitor's satisfaction. In addition, visitor's satisfaction was found to have positive effect on visitor's loyalty such as revisiting intention and word of mouth. As a result, managers of recreation forest need to enhance visitor's satisfaction, to improve rate of revisiting intention and to incite word of mouth through building management strategy.