겨울과 같은 환경에서 곤충은 생존과 번성을 위해 생리학적, 생화학적 및 행동적 메커니즘을 이용하고 있다. 대부분의 곤충은 생리학적 적응가운데 급속내한성(Rapid cold hardiness, RCH) 유기를 통해 기온이 급격히 낮아 지는 외부 환경에 대해 빠르게 적응하고 저온조건에서 생존율을 높인다. 열대거세미나방의 경우 행동적 메커니 즘을 통해 따뜻한 곳을 찾아 장거리 비행을 하며, 생존에 유리한 환경으로 이동한다. 본 연구에서는 열대거세미나 방의 생리적 월동능력과 RCH 능력에 관해 조사하였다. 그 결과, RCH에 의해 혈중 글리세롤의 농도가 증가와 체내빙결점이 하강하는 것을 확인할 수 있었다. 또한, RCH(-10℃, 1h)에 노출된 2령 유충기를 대상으로 4령과 5령 유충기에 단기저온(5℃, 30min)에 노출 시 글리세롤 생합성에 관여하는 유전자(glycerol kinase 1, 2)의 발현이 RCH에 노출되지 않은 대조구와 비교하여 빠르게 발현되었다. 이는, 열대거세미나방의 유전자 수준에서 저온에 대한 단기기억이 존재하는 것을 제시한다.

열대거세미나방이 2019년 국내에 첫 비래한 이후 매년 비래하고 있으며 옥수수 등에서 피해를 주고 있음에 따라 전북지역 주요 옥수수 재배지역에서의 열대거세미나방 발생양상과 약제방제 효과를 조사하였다. 2022년 도에 성페로몬트랩을 이용하여 성충유인량을 조사한 결과 7월 1일 첫 채집되었으며 8월 중순이후 채집량이 증가 하여 9월 중순과 10월 중순에 발생최성기를 보였으며 11월 상순까지 유인되었다. 2022년과 2023년에 식용 옥수 수 재배지역에서 열대거세미나방 유충 피해 조사 결과 6월 수확하는 옥수수에서는 열매피해가 없었으나 9월에 수확하는 옥수수에서는 피해열매율이 30% 이상인 포장들이 관찰되어 재배시기에 따라 피해 정도 차이가 매우 큰 경향이었다. 옥수수 포장에서 열대거세미나방 유충 방제를 위해 2~3령기에 인독사카브 액상수화제를 7일 간격으로 2회 살포한 결과 처리 7일 후 방제효과는 91.7%로 높았다.

Fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is a polyphagous agricultural pest that damages about 80 species of plants. It mainly damages Poaceae and plants used as food resources for humans. Its original habitat is the American continent, but it unintentionally settled in tropical and subtropical Asia, including Africa, India, and Sri Lanka. It occurs every year even in southern China, which is geographically adjacent to the Korean Peninsula, causing damage to crops. In Korea, it was first discovered on Jeju Island in June 2019 and is being discovered every year in Jeju and some inland areas. In 2023, there were a total of 13 discoveries, including those in the Jeju and Jeonbuk regions. Quarantine agency identified the maternal genotypes of all currently discovered individuals using COI and identified differences in genetic traits between individuals using the sex-related Z-chromosome. For comparison with the information on the individuals that invaded the country, 15 individuals from Guangxi and Guangdong provinces in China were collected and secured. Through the analysis of overseas samples, a database has been added to compare genetic information with domestic invasive species, and the reliability of the analysis is expected to increase.

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), which is native to tropical and subtropical regions of the Western Hemisphere is now annually arrives in Korea. In this study, we developed loop-mediated isothermal amplification (LAMP) assay, one of the main merits of which is a rapid identification of target species. Five among 11 FAW-specific loci tested successfully provided a consistent reaction when ten FAWs, which were collected from eight localities in four countries were tested, whereas the 13 non-target species were not amplified. To increase in-field applicability of the method all life stages, reaction time, and different periods after death was tested using the quick extracted DNA. Our FAW diagnostic protocol can be completed within 30 min, from the process of extracting genomic DNA from an egg or a 1st instar larva to species determination.

Maize is an important cereal crop widely grown in all of Nigeria’s agroecology based on its economic and food values. This has led to its optimum production with Nigeria ranking top 12th maize producer in the world. Presently, the fall armyworm (FAW), Spodoptera frugiperda is considered a potential threat to food security in Nigeria due to its devastating feeding pattern on maize and its wide host range. Its invasive and high dispersal nature enhances its spread from its first reported state (Oyo) in early 2016 to the entire 36 states of Nigeria by the year 2018. It accounts for averagely an estimated 34% or more yield reduction in Nigeria’s maize field, hence, a need for an efficient management approach. Although most farmers rely on the use of insecticide, it is found ineffective because of the inaccessible location of FAW in maize. This study was carried out to investigate the different management approaches adopted in Nigeria to control FAW and its impact on the insect pest population. Conventional measures such as planting improved seeds, avoidance of late planting, and polyculture to increase the natural enemy’s population have been used but with limited control of FAW. Maize lines with aflatoxin resistance or transgenic Bt-maize are found resistant to FAW. Botanicals such as neem extract lowered the percentage of leaf area damage, incidence of FAW larva infestation, and the number of larvae. It is difficult to curtail the menace of FAW through one control method, hence, the need for an integrated approach

In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3rd to 4th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.