Spodoptera species (S. exigua and S. litura) are important pests of several crops and vegetables in Korea. We investigated development processes of Spodoptera species under constant temperatures (20, 25 and 30 oC) regimes and relative humidity (RH) (30-35, 50-55, 70-75, and 90-95%) conditions. We collected eggs of Spodoptera species by releasing them into a rectangular box inner walls covered with a sheet of white paper. Temperature and RH significantly impacted on oviposition, immature survival, adult emergence and longevity of Spodoptera species. Maximum number of eggs, shorter developmental time, higher adult emergence with longer longevity were reported in 70-75% at 30 oC. Minimal eggs and larval survival were recorded in 30-35% and 90-95% RH, respectively. This results suggest that temperature and RH had individual apparent effect on the developmental processes of Spodoptera species instead interactive effect. Therefore, there is chance to cause a significant damage to field crops and vegetables in 70-75% at 30 oC.

애긴노린재류(Nysius species)는 세계에 널리 퍼져 있는 해충으로 기주범위는 매우 넓으며 특히 국화과의 주요해충으 로 알려져 있다. 최근 종실 들깨에서 피해가 보고되고 있으며, 들깨를 수확할 때 종실과 같이 다량의 애긴노린재류가 함께 혼입되어 그 발생밀도가 매우 높음을 알 수 있다. 본 연구에서는 이러한 애긴노린재류가 들깨에 미치는 영향을 연구하고자 들깨 종실의 무게변화와 발아율을 조사하였다. 건전한 들깨(들샘) 종실에 애긴노린재류 성충 0, 5, 10, 15, 20, 25마리를 인위적으로 접종하여 3일과 5일 후 들깨 무게를 측정하였다. 측정결과 접종한 노린재 밀도가 5, 10, 15, 20, 25마리로 높아질수록 0마리일 때 보다 들깨 무게가 3일 접종 시에는 각각 2.6, 5.5, 9.0, 10.5, 11.0% 감소하였고, 5일 접종 시에는 각각 2.9, 9.9, 12.0, 17.6, 18.1% 감소하였다. 애긴노린재의 밀도가 높아질수록 종실의 무게가 감소폭은 컸으며, 3일 접종 때보다 5일 접종 때가 들깨의 무게는 더욱 많이 감소하였다. 또한 들깨무게가 감소함에 따라 발아율도 함께 떨어졌다. 노린재 흡즙에 의한 피해로 들깨 종실의 무게가 감소하였다는 것을 추정할 수 있으며, 이로 인해 들깨의 발아율이 떨어진 것으로 생각된다.

콩, 팥, 들깨 및 매실원에서 집합페로몬 로케트트랩에 의한 톱다리개미허리노린재의 유인효과를 조사하였다. 콩포장에서 톱다리개미허리노린재와 썩덩나무노린재의 집합페로몬(aggregation pheromone; AP)를 각각 및 조합하여 로케트트랩에 주입하여 콩포장 내 10, 5 및 0m(콩포장 가장자리) 지점과 콩포장 바깥 5m(휴반) 지점에 설치한 결과 톱다리개미허리노린재의 유인수는 콩포장 바깥 5m(휴반)에서 가장 높았으며, 다른 설치지점간에는 차이가 없었다. 이러한 경향은 썩덩나무노린재의 유인수도 같은 경향을 나타내었다. 또한 톱다리개미허리노린재와 썩덩나무 노린재의 AP를 각각 및 조합하여 로케트트랩에 주입하여 팥포장내 5m, 팥포장의 가장자리, 들깨포장내 5m, 팥과 들깨포장의 경계, 팥포장밖 5m 지점에 설치하여 톱다리개미허리노린재와 썩덩나무노린재의 유인수를 조사한 결과 이들 노린재류의 유인수는 팥 포장밖 5m 지점에서 가장 높았다. 한편, 매실원에서 집합페로몬 로케트트랩의 설치지점 에 따른 노린재류의 유인수는 톱다리개미허리노린재는 가장자리에서 가장 많았고, 다음은 과원내>과원밖 5m>과원밖 10m>과원밖 15m>과원밖 20m 순으로 나타났으며, 썩덩나무노린재는 가장자리에서 가장 많았고, 다음은 과원밖 5m>과원밖 10m>과원밖 15m>과원밖 5m 및 과원내의 순으로 나타났다. 이러한 결과로 보아 농작물 재배포장에서 집합페로몬에 의한 노린재류의 유인효과는 로케트트랩의 설치지점과 밀접하게 관련이 있다는 것을 알 수 있었다.

콩명나방(Maruca vitrata)은 열대ꞏ아열대성 해충으로 콩의 주요 해충으로 알려져 있으나 국내에서는 팥에서 피해가 큰 해충이다. 콩명나방의 유충에 콩과작물인 콩(대두, 소청자, 풍산나물콩), 팥(홍언), 동부(장채)와 인공사료를 각각 먹이로 제공하여 콩명나방의 발육상을 조사하였다. 조사결과 인공사료를 먹이로 제공한 콩명나방 유충의 용화율과 우화율이 가장 높았고 다음으로 팥과 풍산나물콩을 먹이로 제공했을 때 용화율과 우화율이 높았다. 장채의 경우 유충이 한 마리도 용화하지 못했다. 콩명나방 유충이 용화까지 걸리는 기간은 인공사료를 먹이로 제공했을 때 가장 짧았고 다음으로 팥과 풍산나물콩을 먹이로 제공했을 때 짧았다. 용의 무게 또한 인공사료를 먹이로 제공했을 때 가장 높았고 다음으로 팥과 풍산나물콩을 먹이로 제공했을 때 높았다. 실험결과 팥 이외에 콩과작물에서도 유충이 성충까지 우화할 수 있음을 확인하였다.

Maruca vitrata is one of the destructive pests of tropical legumes. Radiofrequency dependent development and adult performances of M. vitrata were examined at five radiofrequencies of 0 (control), 5, 10, 20, and 30 kHz on artificial diet. The results showed that radiofrequency have significant effects on the life variables of M. vitrata. Radiofrequency exposures on pod borer impacted on life-variables of M. vitrata and negative effects were also transmitted to the successive generations. The adults of M. vitrata were emerged with shorter longevity in case of radio-frequency treatment than untreated. Decreasing the radiofrequency level further reduced the longevity of adults. The shortest adult longevity was recorded for 5 kHz. Radiofrequency treatments have also affected on the adult performance such as weight of adult. The outcomes of this study are discussed in terms of an alternative to chemical treatments.

The Azuki bean weevil, Callosobruchus chinensis L., is a common insect pest of stored products in the world. Radio-frequencydependent oviposition, development and adult performances of C. chinensis were examined at five radio-frequencies of0 (control), 5, 10, 20, and 30 kHz on azuki bean, cowpea, and mung bean seeds. The effects were studied on two successivegenerations of C. chinensis. The results showed that radio-frequency application have significant effects on the life variablesof C. chinensis. Radio-frequency exposures on three seed species not only impacted on developmental time, adult longevityand adult weight but negative effects were also transmitted to the successive generations. Longer developmental time andthe least adults of C. chinensis were emerged with shorter longevity in case of radio-frequency treatment than untreated.Decreasing the radio-frequency level further reduced the adult longevity and increased time for development of adults.The least adult emergence and short longevity was recorded for 5 kHz treatment. Radio-frequency treatments have alsoaffected on the adult performance such as weight of adult. The life variables of C. chinensis are discussed in terms oftargeting susceptibilities to radio-frequencies in storage as an alternative to chemical treatments.

The azuki bean weevil, Callosobruchus chinensis L., which is one of the notorious stored grain insect pest. Temperature-dependent development of C. chinensis. was examined at six temperatures of 14, 18, 22, 26, 30, and 34℃ on azuki bean and cowpea seeds. The total developmental time (egg to adult) decreased with increasing temperature from 14 to 34℃ on both seeds. However, total developmental time varied from 127.9 and 125.9 days at 14℃ to 19.9 and 20.3 days at 34℃ on azuki bean and cowpea seeds, respectively. The lower temperature thresholds (Tmin) were estimated to be 9.52℃ and 10.36℃, and the thermal constants (K) were 526.31 DD and 454.54 DD, on azuki bean and cowpea using general linear model, respectively, and the lower temperature thresholds and the thermal constants estimated by Ikemoto-Takai linear models were 10.63℃ and 10.79℃, and were 466.18 DD and 436.28 DD, on azuki bean and cowpea, respectively. These findings on thermal requirements and temperature thresholds can be used to predict the occurrence, number of generations and population dynamics of C. chinensis.

The development of resistant seeds to manage this pest is a big challenge for breeders. We investigated the oviposition preference and development of C. chinensis on two susceptible mungbean cultivars (Seonwha and Gyeongseon) and one previously reported resistant cultivar Jangan, compared to the susceptible cowpea, Yeonbun, by offering a multiple choice test and a no-choice test. Additional, insect stage wise development of C. chinensis was also examined at four temperatures (20, 25, 30 and 35℃). The both choice tests results showed that the cowpea is the most suitable seed host for oviposition. Total developmental time from egg to adult stage ranged from 27.01 to 38.2 days, and developmental time was shortest on the cowpea and longest on Jangan mungbean. However, no successful development of C. chinensis on Jangan mungbean occurred at all constant temperatures. Higher rate of adult emergence and longer adult longevity were found on cowpea and mungbean except Jangan mungbean. Results suggest, higher performance of C. chinensis on cowpea and mungbean might be governed by physical as well as chemical attributes of the seeds. Thus, Jangan mungbean could be stand as a resistant one against bruchids and it could be a resistant sources for successful breeding.