스키미투스응애(Stratiolaelaps scimitus)는 토양에 서식하는 해충의 포식성 천적으로 알려져 있으며, 꽃노랑총채벌레 (Frankliniella occidentalis)와 아메리카잎굴파리(Liriomyza trifolii)의 번데기를 친환경적으로 방제하는 데 이용되고 있다. 본 연구에서는 꽃노랑총채벌레의 유충, 번데기, 성충을 대상으로 스키미투스응애의 포식량을 조사하였고, 총채벌레의 번데기에 기생하는 천적인 곤충병원성 선충(Steinernema carpocapsae GSN1 strain과 Heterorhabditis bacteriophora Hamyang strain)과의 종간경쟁에 대해서도 시험을 수행하였다. 스키미투스응애는 꽃노랑총채벌레의 유충, 번데기, 성충을 하루에 6마리, 3마리, 4마리 정도 포식하는 것으로 조사되었다. 스키미투스응애는 주로 토양에 서식하기 때문에 총채벌레의 유충과 성충을 접촉할 기회는 많지 않지만, 접촉만 이루어진다면 하루에 4∼6마리 정도는 포식할 수 있음을 알 수 있었다. 또한 총채벌레의 번데기에 기생하여 죽일 수 있는 천적으로 알려진 곤충병원성 선충과 스키미투스응애의 종간경쟁을 조사한 결과 스키미투스응애는 곤충병원성 선충의 감염충을 포식하지 않았으 며, 역시 곤충병원성 선충도 스키미투스응애에 기생하지 않았다. 두 천적을 동시에 꽃노랑총채벌레 번데기에 처리 후 기생력과 포식력을 알아본 결과, 스키미투스응애의 포식활동이 더 높았다.
Mushroom mites have recently caused severe damage to sawdust beds, mushroom mycelia, and fruiting bodies; therefore, they have reduced the production of the button mushroom, Agaricus bisporus, in greenhouses. There are currently no registered pesticides for mushroom mites. It is necessary to selectively control mushroom flies and mites without affecting the growth of the mushroom. We examined biological control of mushroom mites using predatory mite Stratiolaelaps scimitus in button mushroom cultivation. As a result, a three times treatment (1 treatment after water cleaning, 1 treatment after fungus inoculation, and 1 treatment before or after casing) was most effective at controlling mushroom mites, with 3.000 predatory mites (3 bottles) scattered evenly over 165–230 ㎡ every 1–2 m. Predatory mite Stratiolaelaps scimitus could control mushroom flies and mites at the same time and could be used at any time during cultivation.
Predatory gamasid mite (Acari: Mesostigmata) is living in soil and litter. They feed on nematode, collembolan and insect larvae. This research compared diversity of gamasid mite in organic and conventional apple orchards. Soil samples were collected in spring season of 2011 to 2012 (5 for each orchard system). Fifteen families, 54 species and 15 families, 50 species were collected from organic and conventional orchards, respectively. In total 18 families and 77 species of gamasid mite were collected. Shannon Diversity was average 2.5 in organic orchard and 2.3 in conventional orchard. Major dominant species was Eugamasus fujisanus (Parasitidae) in organic orchard and Uropoda hokkaidoensis (Uropodidae) in conventional orchard. Parasitidae and Uropodidae were preferred in soil surface, large soil pores and decaying organic material litter. Future, more research on composition of gamasid mite, biotic and abiotic factors in orchard system are demanded.
Strawberry, Fragaria ananassa Duchesne, is one of the important horticultural crops cultivated in greenhouses. Tetranychus urticae is one of major strawberry pests, and Neoseiulus californicus and Phytoseiulus persimilis have been used as biological control agents for control of T. urticae. The interactions between T. urticae and N. californicus and between T. urticae and P. persimilis were investigated to compare their control efficiency for T. urticae on a spatially-structured strawberry leaf disc area at different temperatures and on different treatments. The experimental arena was an array of leaf discs (3 cm diameter) placed upside down on a water-saturated cotton pad in an aluminum pan (17.4 x 21.5 cm). Twenty leaf discs (4 x 5) were placed adjacent each other for allowing dispersal of T. urticae and its predatory mites. The temperature conditions were 20, 25, and 30°C and there were six different treatments. The overall population densities of T. urticae were influenced by temperature (20, 25, and 30°C) in N. californicus treatment. In the same temperature condition, P.persimilis was more effective than N. californicus to control T. uritcae. Two predator systems were better than one predator systems to suppress the population density of T. urticae at 25°C. Some results of this study could be used to understand the spatial association of T. urticae and its predatory mites in greenhouse crops and fields.
On the leaf disc of fruit vegetables (cucumber, sweet pepper, tomato, egg plant, oriental melon), it has been evaluated that the capability of four predatory mites (Amblyseius swirskii Athias-Henriot, Neoseiulus barkeri (Hughes), N. cucumeris (Oudemans), N. californicus (McGregor)) to prey on the eggs of Bemisia tabaci (Gennadius) and to lay own eggs. The most aggressive mite was A. swirskii which had consumed about 9~12 eggs in a day. The quantity of eggs consumed by N. barkeri, N. cucumeris and N. californicus was about 6~9, 4~6 and 1~4, respectively. The most productive mite was also A. swirskii which had laid about 1.2~1.9 eggs in a day. The others could not lay more than 0.5 eggs in a day.
The two-spotted spider mite, Tetranychus urticae Koch, is one of major pests in greenhouse strawberry. Two predator mites, Neoseiulus californicus (McGregor) and Phytoseiulus persimilis (Athias-Henriot), have been widely used for control of T. urticae because they have good functional and numerical responses and searching behaviors. The study of single species releasing and combined releasing of two predatory mites, N. californicus and P. persimilis, was conducted on connected strawberry leaves. The experiments were run under laboratory conditions, 24±1oC, 50-65% RH, and a photoperiod of 16:8 (L:D) h. The excised leaf disk (diameter 3cm) of two strawberry varieties – Maehyang, Sulhyang– were placed upside down on a water-saturated cotton pad in an aluminum pan (width × length 17.4 × 21.5 cm). Twenty leaf disks were placed on each experimental set and the disks (width × length 4×5 cm.) were connected with each other for dispersing of T. urticae and its predatory mite. There were four different experiments – two strawberry varieties and two treatments (releasing single predatory mite, releasing two predator mites). The experiment sets were covered with plastic cage to protect from invading other insects and mites. All life stages of T. urticae and predatory mites were recorded until all mites were vanished. The data were transformed by ln (x+1). Repeated-measures analysis of variance was used to compare the temporal variation in the overall T. urticae and predatory mite density. The average number of T. urticae per leaf arena was significantly different among treatments in Sulhyang (Treatment, df=3, 196, F=17.86, P=0.0001; Time, df=6, 1176, F=47.76, P=0.0001; Time ×Treatment, df=18, 1176, F=22.06, P=0.0001) and in Maehyang (Treatment, df=3, 196, F=42.07, P=0.0001; Time, df=6, 1176, F=64.51, P=0.0001; Time x Treatment, df=18, 1176, F=24.19, P=0.0001). When N. californicus was introduced to P. persimilis system with diminishing prey, P. persimilis population increased more rapidly than N. alifornicus but P. persimilis was displaced by N. californicus. In single or combined releasing system, N. californicus persisted longer after prey depletion than P. persimilis. We examined population growth of P. persimilis and N. californicus in single and combined predatory mite released system with diminishing prey.
The toxicities of 37 commercial pesticides for citrus pests were evaluated to N. fallacis. Eight fungicides (difenoconazole, imibenconazole, azoxystrobin, dithianon, fluazinam, procymidon, strep-tomycin, tribasic copper sulfate), three insecticides (dichlovos, imidacloprid, thiamethoxam) and four acaricides (milbemectin, tetradifon, dicofol, spirodiclofen) had lower effect to the hatchability of eggs N. fallacis. Six fungicides (propineb, difenoconazole, imibenconazole, azoxystrobin, dithianon, procymidon) and three acaricides (bifenazate, tetradifon, spirodiclofen) showed lower contact toxicity to adult N. fallacis. The secondary toxicity of 26 pesticides to N. fallacis adult were evaluated. Two fungicides (fluazinam, streptomycin) and 3 acaricides (machine oil, cyhexatin, halfenprox) showed low toxicity when the prey (eggs of spider mite) was treated with pesticides.
포식성 천적 O. kashmiricabenefica의 식식성 응애류 3종에 대한 포식량, 포식선호성 그리고 동족포식을 조사하였다. 성충의 일평균포식량은 먹이인 응애의 밀도와 온도가 높을수록 증가하였다. 항온조건하에서 O. kashmirica benefica 성충의 일평균포식량은 귤응애, 점박이응애, 차응애 성충을 각각 21.9, 13.5, 14.1마리씩 포식하였다. 유충의 포식량은 영기가 증가할수록 많아져서, 1령, 2령, 3령 유충이 각각 2.8, 11.2, 25.4마리의 귤응애 성충을 포식하였다. O. kashmirica benefica 유충은 귤응애, 점박이응애, 차응애 성충을 유충기간(5일, )동안 각각 77.7, 61.3, 73.0마리씩 포식하였다. O. kashmirica benefica 유충과 성충은 글응애, 점박이응애, 차응애 중에서 특정한 종을 선호하는 경향은 없었으며, 먹이가 없을 때에도 동족포식 정도는 매우 낮았다.
점박이응애, 간자와응애와 긴털이리응애에 대하여 abanectin 의 독성을 leaf disc 법으로 시험하였다. A-bamectin은 점박이응애나 간자와응애보다 긴털이리응애에 대하여 독성이 매우 낮았다. 긴털이리응애 암컷성충은 처리 농도가 증가할수록 생존율이 크게 감소하였으나, 0.38~6ppm에서 8~78%가 생존하였으며, 산란수도 농도 증가에 따라 크게 감소하였다. 모든 처리 농도에서 긴털이리응애 난의 부화나 생존 유.약충의 발육에는 영향이 없었다. 유.약충의 생존율은 농도 증가에 딸라 감소하여 0.38~3ppm에서 42~90%가 성충으로 우화하였다. 중독된 먹이를 섭식한 긴털이리응애 암컷 성충은 생존율에는 별 영향이 없었지만, 산란수와 차세대의 성비에는 상당한 영향을 받았다. 또한 긴털이리응애에 상대적으로 영향이 적어 아치사농도라할수 있는 0.38~0.75ppm에서의 abamectiondms 점박이응애나 간자와응애의 종합관리에서 긴털이리응애와 식식성응애류의 밀도비율 조절에 유요할것으로 생각된다.