This study was conducted to identify an insect species in Genus Ostrinia (Lepidoptera: Crambidae) that gave serious damage to the red bean, Vigna angularis. The species has ever been described as O. zaguliaevi in the previous presentation (Jung et al., 2010). Because, however, inconsistent information has been recognized for the species, we reviewed characteristics in morphological, molecular and sex pheromone levels, and host-range. Male genitalia had 3-lobed uncus and tibia of midleg showed massive type. The morphology indicated that the species might be one of O. zaguliaevi, O. scapulalis and O. zealis. Partial nucleotide sequences of cytochrome oxidase subunit Ⅰ(COⅠ) and Ⅱ genes were not identical with those of the 3 species in GenBank, respectively. The deduced amino acid sequence of COⅠ was not identical with that of O. zealis. In the 23 analyses that sex pheromones were checked, (Z)-9-tetradecenyl acetate, which was reported in the sex pheromone components of both O. zaguliaevi and O. zealis, was not detected at all. An intensive study in Japan has reported that the feeding habit of O. scapulalis is polyphagous, while that of O. zaguliaevi is monophagous (only in Petasites japonicus) (Ishikawa et al., 1999). After considering all these information, we concluded that it is reasonable to decide that the insect species in the red bean in Korea is O. scapulalis.

A total of 5,000 ethanolic and methanolic extracts of different plant species from 23 nations including Costa Rica, Vietnam, Philippines, India, South Africa, Pakistan and Peru were evaluated for their larvicidal activities against Aedes aegypti, the major vector of dangue, dangue hemorhagic fever and yellow fever. The larval mortalities were observed 24h after treating the larvae to the extracts. At 500 ppm, 179 extracts showed >80% larval mortality in the 24h exposure. Among the extracts tested, the highest larval mortality was observed in the extracts of Piper guianense, Piper nigrum, Piper mocropodum, Piper sem-immersum, Piper magen and Piper pubicatulum. The LC50 value of extract P. guianense, P. nigrum, P. mocropodum, P. sem-immersum, P. magen and P. pubicatulum were 8.84, 11.48, 8.84, 13.86, 9.48 and 10.12 ppm against Ae. aegypti. It is suggested that P. guianense, P. nigrum, P. mocropodum, P. sem-immersum, P. magen and P. pubicatulum can be developed as potent larvicidal agents against Ae. aegypti.

DNA barcoding uses a 650 bp segment of the mitochondrial cytochrome c oxidase I (COI) gene as the basis for an identification system for members of the animal kingdom and some other groups of eukaryotes. PCR amplification of the barcode region is a key step in the analytical chain, but it sometimes fails because of a lack of homology between the standard primer sets and target DNA. Two forward PCR primers were developed following analysis of all known arthropod mitochondrial genome arrangements and sequence alignment of the tRNA-W gene which was usually located within 200 bp upstream of the COI gene. These two primers were combined with a standard reverse primer (LepR1) to produce a cocktail which generated a barcode amplicon from 125 of 141 species that included representatives of 121 different families of Hexapoda. High quality sequences were recovered from 79% of the species including groups, such as scale insects, that invariably fail to amplify with standard primers. The current results show that primers designed to bind to highly conserved gene regions upstream of COI will aid the amplification of this gene region in species where standard primers fail and provide valuable information to design a primer for problem groups.

Although DNA barcode coverage has grown rapidly for many insect orders, there are some groups, such as scale insects, where sequence recovery has been difficult. However, using a recently developed primer set, we recovered barcode records from 373 specimens, providing coverage for 75 species from 31 genera in two families. Overall success was >90% for mealybugs and >80% for armored scale species. The G·C content was very low in most species, averaging just 16.3%. Sequence divergences (K2P) between congeneric species averaged 10.7%, while intraspecific divergences averaged 0.97%. However, the latter value was inflated by high intra-specific divergence in nine taxa, cases that may indicate species overlooked by current taxonomic treatments. Our study establishes the feasibility of developing a comprehensive barcode library for scale insects and indicates that its construction will both create an effective system for identifying scale insects and reveal taxonomic situations worthy of deeper analysis.

Recently, hundreds thousands of CO1 barcodes have been produced in many insect groups however, relatively little is known in Hemiptera. In this study, we newly determine 1173 sequences for 374 species distributed among 190 genera and 33 families collected mostly from North America. Average age of the specimen was 12.2 years and about 70% of the specimens produce barcode over 500 bp among examined 1700 specimens. Con-generic divergency calculated by K2P distance was 9.99 which was 11fold higher than the mean intraspecific variation. A steady increase of genetic variation through increasing taxonomic levels was also observed. We found several taxon groups with deep divergency (over 2.0 K2P distance) which were morphologically identified as a same species. Some mixed clusters with several species were also found and suggested more detailed study for these clusters through both morphological and molecular biological method.

Because mealybugs are one of the most economically damaging groups of insects on food crops and ornamental plants, some are regulated-species in quarantine with the foreign trade of agricultural products. However, the absence of morphological characteristics enabling the discrimination of early life stages often causes a significant delay or the rejection of a shipment when fruit is discovered containing them, causing much economic loss. A PCR-based method for species identification was developed for six mealybug species known from Korean pears including two regulated insects, Planococcus kraunhiae (Kuwana) and Crisicoccus matsumotoi (Siraiwa). Six sets of species-specific primers were designed based on the sequence comparison of the internal transcribed spacer 1 and 2 regions. Efficiency tests against many mealybug samples showed that this method could effectively discriminate different mealybug species regardless of their developmental stages. Blind tests against 11 field collected mealybug nymph samples indicated that a single PCR is enough to discriminate unidentified mealybugs collected on Korean pears. This new method will be useful in quarantine as well as pest monitoring by providing an easy, accurate way of identifying any life stage of these mealybugs.

총 22개의 감 SSR primer set을 사용하여 주요 재배품종 17품종, 수집한 단감 변이개체 13종 등, 총 30개의 유전적 연관성을 분석하였다. 획득한 469개의 다형성 밴드를 이용하여 UPGMA 방식으로 유사도 및 집괴분석을 수행한 결과, 30개의 품종 및 수집 계통들은 크게 2개의 그룹(cluster)으로 나뉘어졌으며, 제 1 cluster는 다시 3개의 subcluster로, 제 2 cluster는 다시 2개의 subcluster를 형성하였다. 이는 수집 계통들이 기존 대조품종들과 서로 동일군으로 분포되고 있어 형태적으로 유사할 수 있고 근연되어 있지만, 유전자적 수준에서는 다른 조성을 가지고 있음을 보여준다. 평균 유사도의 값은 0.164 이였고 품종간 가장 높은 유사도 값(0.31)을 나타낸 것은 ‘차랑’과 ‘전천차랑’이였고, 가장 낮은 유사도 값(0.02)를 나타낸 것은 Ⅱ 그룹과 비교하여 Ⅰ 그룹에 속하는 ‘Rojo Brillante’였다. 본 연구에 사용된 22 SSR primer set을 통해, ‘차랑’과 ‘전천차랑’을 제외한 대조품종과 수집 계통간의 구별이 가능하여 향후 신품종 개발시 품종보호를 위한 특이적 마커로 효율적으로 사용될 수 있을 것으로 판단된다.