RNA interference (RNAi)-based strategy has been developed to control various phytophagous chewing pests. However, only a few cases of RNAi-based control success have been reported for sucking pests, suggesting that sucking pests likely ingest less amount of transgenic subcellular hairpin RNA (or dsRNA). In this study, as the basic information for the establishment of ingestion RNAi against sucking pests, feeding amount and time course of plant subcellular fractions of the four sucking pest species (Frankliniella occidentalis, Frankliniella intonsa, Tetranychus urticae and Nilaparvata lugans) were determined by quantitative PCR (qPCR). Adults of the four species were starved for 24 h and then fed with kidney bean leaf (F. occidentalis, F. intonsa, T. urticae) or rice leaf (N. lugens) for 48 h. The leaf-fed adults were collected every 6-h interval and their genomic DNA was extracted. The ingested fractions of chloroplast and nuclear were quantified using rubisco and 50s rRNA as marker genes, respectively. The ingested amount of rubisco and 50s rRNA genes in F. occidentalis, F. intonsa and T. urticae showed rapid increasing pattern after feeding and then slightly reduced over time. In contrast, N. lugens neither ingest nuclear nor showed any distinct feeding pattern of chloroplast. These results demonstrate that F. occidentalis, F. intonsa and T. urticae ingest both chloroplasts and nucleus along with cytosol as cell-feeders but N. lugens, a phloem sap feeder, does not ingest nucleus during sucking. Our findings further suggest that ingestion RNAi-based control strategy would work better for cell-feeding sucking pests compared to phloem sap-feeding sucking pests.

The residual amount of fumigant was measured over time after fumigation on pine wilt disease infected Pinus koraiensislogs in the forests of Yeoncheon and Pocheon. Dimethyldisulfide (DMDS, 99.6%) was treated in large scale fumigation(100m3) in Yeoncheon and measured after removing tarpaulin cover in the 2 weeks of fumigation. DMDS was detectedat the highest concentration of 77.9 mg/kg in the 2nd week of treatment and decreased to 0.6 mg/kg in the 24th week.Metam-sodium (25%) was treated in small scale fumigation (1m3) in Pocheon and the amount of methylisothiocyanate(MITC) was measured after removing tarpaulin cover at each time of investigation. MITC was detected at the highestconcentration of 72.0 mg/kg in the 2nd week of treatment and then decreased to 7.0 mg/kg in the 24th week. However,unlike DMDS, MITC in the 12th week was detected at high concentration similar to the 1st week, indicating that thecontinuity of the sealing with tarpaulin would have a decisive influence on the residual amount change in fumigated logs.

In this paper, it is examined how the amount of review time per applicant to a college admission officer system is connected with the performance of the selected students after they enter the college. About five years ago, college admission officers syste

A visible-light photoactive photocatalyst was synthesized successfully by means of cogrinding of anatase- in ambient, followed by heat-treatment at in air environment. In general, it is well known that the grinding-operation induces phase transformation of a- to rutile . This study investigates the influence of the amount of gas on the phase transformation rate of a- and enhancement of visible-light photocatalytic activity, and also examines the relation between the photocatalytic activity and the period of grinding time. The phase transformation rate of a- to rutile is retarded with the amount of NH3 injected. And the visible-light photocatalytic activity of samples, was more closely related to the period of grinding time than amount injected, which means that the doping amount of nitrogen into more effective to mechanical energy than amount injected. XRD, XPS, FT-IR, UV-vis, Specific surface area (SSA), NOx decomposition techniques are employed to verify above results more clearly.