Honeybees are inevitably threatened by various pathogens including Sacbrood virus (SBV) and Galleria mellonella. Recently, RNA interference (RNAi) has been suggested as a promising strategy for suppression of honey bee viruses. Also, Bacillus thuringiensis (Bt) has been widely applied for the control of lepidopteran pests such as G. mellonella. In this study, it was intended to develop dsRNA production platform using Bt. For this, the pHT1K-SBV vp1 vector which transcribes sense and anti-sense SBV vp1 gene under control of Cyt1Aa sporulation-dependent promoter was introduced into Bt strain NT0423 expressing Cry1-types toxins. SBV replication was suppressed in the worker A. cerana ingested dsRNA produced from the Bt transformant. Crystal proteins from the Bt transformant showed high level of insecticidal activity against 4th instar larvae of G. mellonella.

Mosquitoes are medically important insect pests that act as vectors of various diseases when they feed on humans. Insect growth regulators (IGRs) could become an effective alternative to control mosquitoes because of their high specificity and relatively low toxicity to environment. Recently, we have developed high-throughput juvenile hormone antagonist (JHAN) screening system based on yeast-two hybrid assay. Actinomycetes have been reported to produce various bioactive compounds including insect growth regulators (IGRs). In this study, culture filtrates and mycelia extracts of 2,875 actinomycetes isolates screened for their IGR activities and mosquitocidal activities. Among 75 culture filtrates and 17 mycelia extracts with JHAN activities, 19 culture filtrate and 3 mycelia extracts showed high level of mosquitocidal activities against 3rd instar larvae of Aedes albopictus. These results suggested that secondary metabolites of actinomycetes could be used as environmentally benign mosquitocidal agents.

In order to investigate novel insect growth regulators (IGRs) from actinomycetes, 363 isolates of actinomycetes were tested for their IGR activities. Among them, Streptomyces sp. AN120537 showed the highest juvenile hormone antagonist (JHAN) activity and significant insecticidal activities against larvae of Aedes albopictus and Plutella xylostella. In addition, the dead larvae showed morphological deformities such as contraction of body segments or pigmentation of all body parts. Through liquid chromatography and bioassay-guided fractionation, 7 IGR compounds were identified from the crude hexane extract of AN120537. These results suggested that Streptomyces sp. AN120537 could be useful resources for development of eco-friendly insecticidal agents.

Bryopsis africana and Pyropia kinositae are reported for the first time on the list of Korean marine algal flora based on integrated morphological-molecular study. Bryopsis africana from Korea is recognized with distinct main axes, robust thalli, pinnately and radially branched above, and basally denuded. Phylogenetic analyses revealed that B. africana was placed within a clade of Bryopsis. Bryopsis africana differs from B. corymbosa by 2.7% gene sequence divergence. Pyropia kinositae is characterized by oblong to lanceolate thalli, entire margin, purplish red in color, twice as long as broad cells in transversal section view. Phylogenetic analyses revealed that P. kinositae was placed within a clade of Pyropia. Pyropia kinositae differs from P. tenera by 1.5-1.8%, P. ishigecola by 1.2-1.3%, and P. yezoensis by 1.5-1.8% gene sequence divergence respectively.

Detailed morphological studies and molecular analyses based on plastid-encoded rbcL gene sequences were undertaken on Peyssonnelia species, a poorly known genus from Korea. We report new records for the Korean coast, Peyssonnelia harveyana and P. rumoiana. Peyssonnelia harveyana is chiefly characterized by P. rubra-type anatomy, closely packed perithallial filaments in firm matrix, hypothallial filaments arranged in parallel rows, thalli with appressed margins, hypobasal calcification, and unicellular rhizoids. Peyssonnelia rumoiana is principally characterized by two vegetative features, hypothallial filaments arranged in a polyflabellate layer, and perithallial filaments arising from the whole upper surface of each hypothallial cell (Peyssonnelia rubra-type anatomy). Our rbcL analyses revealed that P. harveynana and P. rumoiana were placed within a clade of Peyssonnelia. We also propose the new combination, Sonderophycus cauliferus comb. nov., for previous Peyssonnelia caulifera. Phylogenetic analyses revealed that our S. cauliferus was placed within a clade of Sonderophycus.

자동분석기(Rapid Ftow Autoanalyzer) RF A-300을 이용한 쌀의 아밀로스 분석법을 확립하였다. 자동분석기로 분석한 아밀로스 함량을 Williams나 Juliano 등의 방법에 따른 분석결과와 비교하여 본 결과 매우 높은 직선적인 상관관계 (r=0.95**-0.97**)를 나타내었다. 자동분석기를 이용한 분석법으로 얻어진 아밀로스함량은 Juliano등의 분석법에 의해 얻어진 결과에 비해 저ㆍ중 아밀로스 품종에서는 1.0-2.0%가 높게, 고 아밀로스품종에서는 1%정도 낮게 측정된 반면 Williams등의 분석법에 따른 검정결과에 비해서는 2.0-5.0% 정도로 높은 함량을 나타내었는데 검정치가 저 아밀로스품종 쪽일수록 증가정도가 약간 큰 경향이었다. 세가지 분석방법간에 상호 직선적인 상관을 보이면서 쌀가루에 비해 녹말시료에서 아밀로스함량이 약간 높은 경향이었다.