The cotton bollworm, Helicoverpa armigera, is an economically important pest, which harms various kinds of important agricultural crops, such as tomato. The purpose of the present study was to investigate the effect of ionizing radiations (electron beam, X-ray, gamma-ray) on the development and reproduction of H. armigera and to determine the optimal dose of three ionizing radiations for the construction of quarantine technology applicable to tomato export.

Whitefly (Hemiptera: Aleyrodidae) pests, including the sweetpotato whitefly, Bemisia tabaci, and the greenhouse whitefly, Trialeurodes vaporariorum, are economically important in agriculture. With the annual growth of the domestic fresh fruit export market, various quarantine treatment methods are being used to export strawberries of better quality. The purpose of the present study was to investigate the effect of ionizing radiations (electron beam, X-ray, gamma-ray) on the development and reproduction of two species of whitefly and to determine the optimal dose of three ionizing radiations for the construction of quarantine technology applicable to strawberry export.

Whitefly (Hemiptera: Aleyrodidae) pests, including the tobacco whitefly, Bemisia tabaci, and the greenhouse whitefly, Trialeurodes vaporariorum, are economically important in agriculture. With the annual growth of the domestic fresh fruit export market, various quarantine treatment methods are being used to export strawberries of better quality. The objective of the present study was to evaluate the effects of gamma rays on the development and reproductive sterility of B. tabaci and T. vaporariorum. In both species, the eggs were completely inhibited from hatching at 50 Gy, and the emergence of 3rd instar nymphs was completely suppressed at 150 Gy. Some adult B. tabaci and T. vaporariorum spawning occurred at 100 Gy and 70 Gy, respectively; however, at these irradiation levels, F1 hatchability was completely inhibited. Dosimetry results showed that the penetrating power of gamma ray in the strawberry-filled box was the lowest at the mid-box position. Therefore, B. tabaci and T. vaporariorum were placed in the middle of the strawberry-filled box and irradiated. A gamma-ray irradiation of 100 Gy suppressed the development and reproduction of eggs and adults in both B. tabaci and T. vaporariorum. However, the development of 3rd instar nymphs was inhibited at 300 Gy for B. tabaci and 200 Gy for T. vaporariorum. Our data suggest that at least 300 Gy should be used for the control of these two types of whitefly for strawberry export.

Acaricidal activities of 63 commecial pesticides against the longhorned tick, H. logicornis were investigated. Twenty-two pesticides (4 cabamates, 5 organophophates, 9 pyrethroids, 1 octopamine receptor agonists, 1 diamides, and 1 unknown) against adults H. logicornis showed >80% mortalities after 72 h of treatment. The residual effect of 22 pesticides was investigated at 1, 2, 3, 7, and 10 day intervals on grass for H. logicornis adults and nymphs. Eight and twenty pesticides in H. logicornis adults and nymphs showed >80% acaricidal activity at 3 days after the treatment, respectively. 7 days after the treatment, H. logicornis adults showed <60% acaricidal activity in all pesticides, but 7 pesticides (benfuracarb, gamma cyhalothrin, cypermethrin, lammda cyhalothrin, fenvalerate, cyantraniliprole, fluxametamide) showed >80% acaricidal activity in nymphs. all pesticides exhibited <60% acaricidal activity after 10 days of treatment both adults and mymphs, except benfuracarb showed 96.7% mortality in H. logicornis nymph.

The green peach aphid, Myzus persicae Sülzer, is an important sap-sucking pest of many plants, including Chinese cabbage. The objective of this study was therefore (1) to determine the effects of sublethal concentrations of afidopyropen, sulfoxaflor, and spirotetramat on adult longevity and the fecundity of M. persicae, and (2) to study the feeding behavior of M. persicae on Chinese cabbage leaves treated with various concentrations of these three insecticides. Longevity and total fecundity of M. persicae adults were decreased at concentrations higher than LC30. Feeding behavior analyses using an electrical penetration graph showed that sublethal concentrations of afidopyropen, sulfoxaflor, and spirotetramat had significant effects on the duration of phloem ingestion.

시판되고 있는 51종(단제 21종과 합제 30종)의 살충제를 이용한 꽃노랑총채벌레와 대만총채벌레 성충에 대한 약제 감수성을 검토한 결과 90% 이상의 살충률을 보인 약제 15종을 선발하였으며, 시판되고 있는 합제에서 많은 유효성분들이 오남용되고 있다고 보여진다. 2종의 총채벌레에 대한 살충제 감수성을 비교한 결과 모든 약제에 대하여 대만총채벌레가 꽃노랑총채벌레에 비해 높은 감수성을 보이기 때문에 꽃노랑총채벌 레에 효과 있는 약제로 동시방제가 가능할 것으로 판단된다. 꽃노랑총채벌레를 대상으로 선발된 15종의 약제를 이용하여 약효발현속도(LT50과 LT95), 침투이행성, 잔효성을 비교하였다. 약효 발현속도를 LT95 (hour)값으로 비교했을 때, chlorpyrifos WP, chlorpyrifos + diflubenzuron WP가 2시간 이내로 가장 빨랐고, spinetoram WG은 62.3시간으로 가장 느렸다. Chlorfenapyr SC에서 뿌리와 엽면을 통한 침투이행 효과가 나타났고, spinetoram WG에서 엽면을 통한 침투이행 효과만이 나타났다. 약제 잔효성 실험에서 chlorfenapyr SC는 14일, benfuracarb WG 와 chlorpyrifos WP는 3일까지 효과가 지속되었다. 꽃노랑총채벌레 야외집단(화훼재배지와 과채류재배지)간의 감수성 비교에서는 화훼재배지에서 채집된 집단이 더 낮은 약제 감수성을 보였다.

The present study evaluated the susceptibility of field populations of Plutella xylostella and Spodoptera exigua larvae to four diamide insecticides—chlorantraniliprole, cyantraniliprole, cyclaniliprole, and flubendiamide. All the four diamide insecticides induced 100% mortality in the populations from Seongju (SJ) and Geochang (GC) when treated at a concentration recommended for P. xylostella. However, a very low insecticidal activity was observed in the population from Pyeongchang (PC) with 42.3% 3 d after treatment with chlorantraniliprole. Further, the populations of S. exigua from Cheongju (CJ), Jindo (JD), and Yeonggwang (YG) were not completely controlled by the 4 diamide insecticides. A comparison of susceptibility of S. exigua larvae to chlorantraniliprole between 2014 and 2017 showed that chlorantraniliprole induced 100% mortality in all populations in 2014, whereas a very low insecticidal activity was observed among the populations in 2017. This study can serve as a basis to control pests effectively using diamide insecticides.

The susceptibility of the Frankliniella occidentalis and Frankliniella intonsa was evaluated using 46 commercial insecticides. There were 10 kinds of insecticides as benfuracarb, chlorfenapyr, spinetoram, spinosad, abamectin + chlorfenapyr, abamectin + emamectin benzoate, chlorfenapyr + clothianidin, chlorfenapyr + imidacloprid, clothianidin + spinetoram and dinotefuran + spinetoram, which showed more than 90% mortality against both thrips, F. occidentalis and F. intonsa. Since the F. intonsa is more susceptible than F. occidentalis, it is considered that both thrips can be controlled by insecticides that show insecticidal activity on the F. occidentalis. The effect by the elapsed time after treatment of 10 kinds of insecticides was analyzed as LT50 and LT95 values. Benfuracarb was the fastest in 4.3 h (LT50) and 14 h (LT95), and spinetoram showed the most late time at 13.5 h (LT50) and 62.3 h (LT95), respectively.

4종의 diamide계열 살충제를 이용한 배추좀나방과 파밤나방의 지역계통별 감수성을 조사하였다. 배추좀나방의 경우 성주와 거창지역 집단 에서 4종의 약제 모두 추천농도에서 100%의 살충활성을 보인 반면, 평창지역 집단에서는 chlorantraniliprole에 대해 42.3%의 낮은 살충활성을 보였다. 감수성계통 배추좀나방과 저항성비를 비교한 결과 cyclaniliprole은 비교적 4지역에서 유사하거나 낮은 저항성비(0.1~6.3배)를 보인 반면, 평창지역 집단은 chlorantraniliprole (1,196.3배)와 cyantraniliprole (105.6배), flubendiamide (191.6배)은 매우 높은 저항성비를 보였다. 파밤나방의 경우 청주와 진도, 영광지역의 집단 모두 4종의 약제에 낮은 감수성을 나타났는데, 특히 청주와 진도지역의 집단은 flubendiamide에 대해 100,000배 이상의 저항성비를 보였다. 채집 연도(2014년과 2017년)에 따른 파밤나방에 대한 chlorantraniliprole의 감수성을 비교한 결과 2014년에 채집된 집단들은 모두 100%의 살충률을 보인 반면 2017년에 채집된 집단들은 살충활성이 매우 낮게 나타났다. 본 연구결과는 diamide계열 살충제가 빠르게 저항성이 발현되고 있으며 작용기작이 다른 약제와의 교호살포 등 종합적 방제전략을 수립하는데 기초자료가 될 수 있을 것이다.