총채벌레는 시설재배작물의 주요 해충으로서 짧은 세대, 기피행동 및 살충제 저항성 발달 등으로 인하여 방제가 어려운 실정이다. 뿌리이리응애[Stratiolaelaps scimitus (Womersley)]는 포식성 토양응애로서 땅에 떨어져 용화되는 총채벌레를 포식한다. 본 연구에서는 농가자가생산법에 따라 증식한 뿌리이리응애를 활용하여 2018년 8~9월에 시설재배지 국화에 발생한 총채벌레의 밀도억제효과를 분석하였다. 총채벌레의 초기밀도는 꽃송이 당 약 6마리였다. 온실에 뿌리이리응애 한 상자 처리 시 밀도는 약 1,000마리/m2 정도 된다. 시험기간 동안 총 10상자를 처리하였다. 9월 말 무처리 온실의 총채벌레 밀도는 53.7 ± 7.0마리로 8.8배 증가한 반면에 처리 온실의 밀도는 13.5 ± 1.7마리로 2.1배 증가하였다. 처 리구의 밀도는 무처리구 대비 74.9%가 억제되었다. 즉, 여름기간 국화재배시설의 고온 조건에도 불구하고 뿌리이리응애를 이용하여 총채벌레의 밀도를 억제할 수 있는 가능성이 높다고 판단된다.

Parasitic wasps are a good source of natural enemies for pest control. Due to the presence of unique biodiversity in Ulleungdo and Dokdo Islands, we surveyed aphid parasitoids in these two islands. We collected aphids and their mummies then identified emerged wasps in both morphological and molecular ways. We found 6 species of aphid parasitoids belongs to Aphelinidae and Braconidae. Two species of the genus Aphelinus belongs to Aphelinidae were emerged from Aphis nasturtii and Macrosiphoniella formosatemisiae. Three species of the genus Aphidius belongs to Braconidae were emerged from Ahpis rumicis, M. formosatemisiae and Capitophorus elaeagni. One species of the genus Lysiphlebia belongs to Braconidae was emerged from Aphis gossypii, Molecular analysis provided genetic informations for species diagnosis of parasitoids. We also analyzed genetic and ecological informations of identified parasitoids to evaluate potential source of natural enemies.

Bemisia tabaci is a species complex consist of about 40 cryptic species. This species is also a vector of at least 100 begomovirus including Tomato yellow leaf curl virus (TYLCV). TYLCV transmitted by B. tabaci in a circulative propagative manner but its molecular mechanism is remain unclear. We investigate the transcriptional response of B. tabaci MED to TYLCV infection using next generation sequencing (NGS) analysis. In total 16757 differentially expressed genes between viruliferous and non-viruliferous whiteflies were analyzed. Among them 289 transcripts found significant, where 116 up-regulated and 173 down-regulated. Our results reveal the whitefly-TYLCV relationship and provide important molecular information about virus transmission of vector insects.

Spodoptera litura Fabricius is the serious, polyphagous pest of various crops. Due to the high resistant to most of chemical pesticides, it is hard to control S. litura in the fields. We investigated the virulence of four entomopathogenic nematodes (EPNs) in each larval stage. All EPNs were more effective to younger larvae than older larvae. Mortality, larval penetration rate and reproduction rate were significantly higher in H. indica, S. carpocapsae and S. longicaudum than the H. bacteriophora. Three high effective EPNs induced complete mortality of first instar larvae within 48 h, but of fifth instar larvae within 72 h. These EPNs also highly effective to control S. litura in pot assay. Thus, H. indica, S. carpocapsae and S. longicaudum, can be used as efficient biological control agents of S. litura.