본 연구는 국내분포가 기록된 해충, 네눈쑥가지나방의 발생조사를 위해 실시되었다. 네눈쑥가지나방의 국내분포 발생조사를 실시하기 전 국내에 보고된 문헌과 각 연구기관의 네눈쑥가지나방 DB 및 표본을 확인하였다. 국내 발간된 문헌을 확인한 결과 한국경제곤충, 국립생물자원관에서 발간한 국가생물종목록집 및 다양한 논문과 연구보고서에서 네눈쑥가지나방의 기록을 확인할 수 있었다. DB 및 표본 확인결과 농촌진흥청에서 1924년부터 1996년까지 38건의 DB를 확인하였고, 온난화대응연구소에서 68점의 표본을 확인하였다. 또한 농림축산검역본부 제주지역본부에 서 네눈쑥가지나방의 DB와 186점의 표본을 확인하였다. 국립수목원에서는 1979년부터 2011년까지 183건의 DB를 확인하였고, 국립생물자원관에서는 408건의 DB를 확인하였다. 조사결과를 토대로 네눈쑥가지나방은 우리나라 전 지역에 분포하는 것으로 확인되었다.
본 연구는 네눈쑥가지나방 유충의 공간분포 특성을 분석하여 산란처와 관련된 유충의 감귤원 내로 정착과정을 이해하고자 실시하였다. 노지와 하우스 모두 감귤나무에서는 알이 발견되지 않았고, 부지화 시설재배 하우스의 방충망에서 발견되었다. 시설재배 부지화에서 네눈쑥가지나방 유충은 통계적으로 유의하게 집중분포를 보였다. 온주밀감 노지재배원에서 분산지수(ID)는 전체적으로 1.0내외로 약한 집중 정도를 나타냈다. 하지만, 검정통계량인 d-값은 대부분 조사일에 -1.96에서 1.96 사이에 있어 임의분포가 통계적으로 유의하였다. 집중정도를 나타내는 GI 지수는 전체적으로 낮아 집중정도가 약하였으며, 집중분포로 검정된 경우에도 집중정도는 크지 않았다. 네눈쑥가지나방 유충수의 빈도분포는 포아송(임의분포)과 음이항 분포(집중분포)를 동시 만족시키는 경우가 많았다. 또한 유충 공간분포의 시간적 변화는 초기 정착지점에서 분산하는 양상이 아니라 무작위로 외부로부터 비산하여 새로 정착되는 양상을 보였다. 기타 시설과 노지감귤원에서 네눈쑥가지나방 유충 공간분포 양상의 차이에 대하여 고찰하였다.
Ascotis selenaria is one of most important pest of geometridae moths in citrus orchards causing citrus fruit damages in jeju, Korea. Oviposition site had not been found on citrus tree, but was witnessed at the net adjacent of vinyl covering a green house in 2007. And then, A. selenaria larva highly clumped on the citrus(Shiranui : [C. unshiu × C. sinenesis] × C. reticulata) tree near the oviposition site and the ID(Index of Dispersion) value was 6.81. However, dispersion of A. selenaria larva was not clearly clumped in field citrus(C. unshiu) during 2008 and 2010. The value of GI(Green’s index) was 0.0179, 0.0208, and 0.0064, respectively. Those were so low that A. selenaria larva were distributed almost randomly in field citrus orchard. Consequently, it was assumed that A. selenaria female oviposited on a tree like Cryptomeria japonica surrounding a citrus orchard in field and hatched larva moved to citrus tree by drifting with winds.
감귤원에서 7종의 자나방이 조사되었고, 이 중 네눈쑥가지나방(Ascotis selenaria)의 발생량이 많았다. 감귤 과실 피해는 주로 네눈쑥가지나방 유충에 의 해 발생하는데, 노지 온주밀감은 1~3령의 저령기 유충이 주로 가해하여 무정형의 피해흔을 남기는 반면, 하우스 부지화는 6령 유충에 의해 크게 피해를 입는다. 이러 한 피해증상의 차이는 감귤의 부지화(Shiranuhi: [C. unshiu × C. sinensis] × C. reticulata)와 온주밀감(Citus unshiu)의 착과 특성에 따른 차이로 보인다. 감귤원에 서 자나방류 감귤 과실 피해율은 2008년부터 2010년까지 평균 4.5%였다. 감귤원 에서 네눈쑥가지나방 유충의 공간분포는 무작위분포에 가까운 수치의 군집지수를 보였다. 온주밀감의 신초와 과실의 피해양상을 보면, 5월 중순에 신초피해가 처음 발생 하였고, 6월 상중순에 최성기를 보였다. 이후 봄순이 경화되는 시기인 6월 하순부 터 급격히 감소하여 여름순(7~8월)과 가을순(9~10월)에는 피해가 적었다. 과실 은 봄순이 경화되는 시점(6월 하순 또는 7월 초)부터 증가하여 7월 말경 급증하였 다. 실제 유충 발생시기는 잎과 과실 피해와 비슷하게 발생하는데, 유충은 5월 중순 에 처음 발생하여 6월 중순에 발생최성기를 보였다. 이후 불규칙한 양상을 보이는 데 7월 하순과 9월 상중순에 약한 발생피크를 보였다. 성충 발생은 5월 중순에 발생 최성기를 보였고, 7~9월은년도에 따라 복잡한 발생양상을 보이나, 대개 7월 상순 부터 하순, 8월 하순~9월 상순에 발생 피크를 보였다. 효과적인 네눈쑥가지나방의 방제시기를 예측하기 위하여 실내에서 온도별 네 눈쑥가지나방의 발육기간과 산란을 조사하여 네눈쑥가지나방의 개체군 모형을 구 축하였다. 네눈쑥가지나방의 발육영점온도와 유효적산온도는 각각 알이 10.98℃ 와 83.7 DD, 유충이 9.68℃와 340.7 DD, 용이 9.07℃와 200.7 DD였다. 비선형 모 형으로 알, 유충, 용의 발육속도(1/median day)에 Hilbert와 Logan 모형을, 생리적 연령에 따른 발육완료 분포 값에 Weibull 함수를 적용하여 매개변수를 추정하였 특I-03 다. 산란모형은 총산란수 모형, 생리적 연령에 따른 누적산란율 모형, 생리적 연령 에 따른 생존율 모형으로 구성하였다. 네눈쑥가지나방의 개체군 모형은 알, 유충, 용, 산란 모형을 구성 요소로 하여 각 단계가 완료 될 때마다 전이 되도록 구성하였 다. 월동용을 2 : 3 : 3 : 2 비율로 나눈 그룹을 만들고, 각각의 그룹에 생리적 연령을 -0.3, 0. 0.3, 0.6을 할당하였다. 이 시나리오 조건으로 모의 실행하였을 때 실제 포장에서 1령 유충과 성충의 발생양상과 발생 최성기가 유사하게 모의되었다.
This study was conducted to evaluate Geometridae (Lepidoptera) species as pests and the damage they cause in citrus orchards in Jej u, Korea. Seven geometridae species occurred in citrus orchards: Ascotis selenaria, Ectropis excellens, Menophra senilis, Biston panterinaria, Ourapteryx nivea, Odontopera arida and Hypomecis punctinalis. Among them, A. selenaria was most abundant, followed by E. excellens and M senilis. Most Geometridae larvae fed on citrus leaves, but A. selenaria larvae ate fruits and leaves. Fruit damage of Citrus unshiu appeared as gnawed scars caused by young larvae feeding on fruit surface. Fruit damage on Shiranui fruits appeared as a wide hole or deep scars caused by feeding by mature larvae (6th instar). Citrus leaves damage due to Geometridae larvae was high during May to June. Fruit damage started in late June as the spring-shoots of citrus hardened and increased sharply in late July. In the field experiment, fruit damage in the late season reached 4.2% in both 2008 and 2009 and reached 5.2% in 2010. In citrus orchards, A. selenaria larvae started to appear in mid-May and their populations peaked in mid June, late July, and early to mid-September. Adult males of A. selenaria had a maximum peak in mid-May, and two other peaks in early to late July and late August to early September. A. selenaria male adults were collected in a pheromone traps constantly throughout Jeju Island.
This study was conducted to develop an artificial diet for the mugwort looper, Ascotis selenaria (Lepidoptera: Geometridae), which is an insect pest to leaves of citrus (Citrus unshiu). Corn and soybean powder were selected as main nutrient sources for larvae of A. selenaria after several diets consisted of wheat germ, corn, kidney bean and/or soybean were tested for larval development and survival. A higher amount of the main nutrients in the diet increased the larval survivorship. Addition of yeast and cholesterol in diet increased the larval survivorship. Finally the composition of diet was decided as followings, corn 100 g, soybean 100 g agar 25 g, Brewers’ yeast 30 g, cholesterol 0.5 g, Vanderzant vitamin mixture 2 g, Wesson’s salt mixture 2 g, sorbic acid 2 g, ascorbic acid 2 g, and methyl-4-hydroxybenzoate 2.5 g, and distilled water 1 liter. Development periods of larvae and pupae, survival rate and fecundity of A. selenaria reared on the diet were not significantly different with those on the host plant, citrus leaves. Larvae of early instars were reared in a group, while larvae of later instars (5-6th) were reared individually. Adult mating was conducted in a plastic cage and an oilpaper covered with a gauze was provided as an oviposition site.
Ascotis selenaria, a major geometridae moth in citrus trees, annually damages the citrus leaves and fruits. The surface of young citrus fruit were usually fed by 1st larva of A. selenaria after landing or stepping onto the citrus fruits. To protect the larval damages of citrus fruits needs to predict the accurate occurrence time of the 1st larva for spraying. Because larval occurrences is dependent on the oviposition of adult female and the eggs were not found in/on citrus trees, oviposition model of A. selenaria linked with the egg development model will be helpful of protecting larval damages on citrus fruits. Adult longevity, survival and fecundity of A.selenaria was investigated at 13, 16, 20, 24, 28, 30, 32, and 35℃. The longevity decreased as the temperature increased and the female development rates (1/median longevity) were well described by a modified sigmoid model, which was used to calculate the adult physiological age. Description of the total fecundity was used by a non-linear model: The maximum fecundity of A. selenaria was estimated as 2490 eggs and peaked temperature was 19.7℃ according to the fecundity model. The cumulative age-specific oviposition rate and the age-specific survival rate was well described by 2 parameters Weibull function and a reverse logistic curve respectively. Total fecundity model, age-sepecific oviposition model, and age-specific survival model were incorporated into the oviposition model.
Ascotis selenaria, one of the major Geometridae moths, annually damages the citrus leaves and fruits. This study was focused to identify the sex pheromone components of A. selenaria in order to monitoring and control its population. Adult female and male were usually emerged at the time between 2 hour before and 2 hour afterlights-off in 16L:8D photoperiod. Mating, irrespective in female age, started at 2 hour after lights-off and peaked between 4 hour and 6 hour after lights-off. They copulated for 3 hour 47 min per pair. Gland extract of virgin female was analyzed with GC-MS and GC-EAD.Z,Z-6,9-3,4 epoxy nonadecadiene (Z,Z-6,9-3,4 epo- 19Hy) was identified as the candidate. Both of stereo isomer, Z,Z-6,9-3R,4S epo- 19Hy and Z,Z-6,9-3S,4R epo- 19Hy, showed a strong EAG response in male antennae. Further study like field attraction test should be needed to clarify the sex pheromone composition and in A. selenaria. Age and time were related with the amount of sex pheromone components biosynthesized in A. selenaria gland. 0 day old female had 112.7ng per gland at 5 hour after lights off and the amount was decreased as they aged. The sex pheromone biosynthesis started from lights-off and showed the increasing tendency during scotophase.
Murgot Looper Moth, Ascotis selenaria, is one of the worldwide pests in citrus plants. They usually damages citrus leaves and often makes young fruits injured. In Jeju, it has been discovered that A. selenaria is a pest of two major geometridae moths being occurred in citrus plant and they also had periodically occurred and damaged bean, asparagus, etc. However, physiological and ecological studies were rarely conducted on this species, which maybe resulted from the limitation of rearing method. Therefore, this study aimed on selecting the diet sources and developing mass-rearing method for A. selenaria, in order to make ease or spur a investigation related with A. selenaria. The major sources, selected among the series of semi-artificial diet, were corn and bean powder and adding yeast makes the larva developed well. Cholesterol, one of the minor sources, enhanced the development rate and lowered the mortality during 1 to 3 larva stage. Consequently the semi-artificial diet, suitable for rearing A. selenaria larva, was composed of 25g agar, 100g corn powder, 100g soybean powder, 30g yeast, 0.5g cholesterol, 2g Vanderzant's vitamin mixture, 2g Wesson's salt mixture, 2g sorbic acid, 2.5g methyl-4-hydroxybenzoate(MPH), 2g Ascorbic acid, and 1000 ml distilled water. A. selenaria larvae has 6 developmental stage and the width of head piece was 0.31 mm (1st instar) , 0.51 mm (2nd), 0.85 mm(3rd), 1.37 mm (4th), 2.14 mm (5th), and 3.19 mm (6th). The development period of A. selenaria, reared at 25℃ and 16L:8D photoperiod, was 4.7 day (egg), 3.58 day(1st instar), 1.88 day (2nd), 1.80 day (3rd), 2.46 day (4th ), 2.59 day (5th), 8.10 day (6th), 11.26 day (pupae) when citrus leaves were supplied to the larva. The larvae, fed with the artificial diet(mentioned above), showed similar developmental periods at each developmental stage as much as the case reared with citrus leaves, although the mortality was sometimes a little bit higher. The weight of pupae were 0.614g (artificial diet) and 0.427g (citrus stuff) and female adult moths lay 1094 eggs (artificial diet) and 1054 eggs (citrus stuff).