• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.119-124
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• 2014

Feeding behaviors of the sweet potato whitefly, Bemisia tabaci, and changing of their feeding behaviors were recorded and analyzed with an Electrical Penetration Graph (EPG) analysis against cyantraniliprole. The characteristic patterns of feeding behaviors investigated were as follows; NP (non probing), pathway phase waveform, waveform of feeding xylem. In results, B. tabaci did not almost feeding the phloem. And It was not appeared potential drop during recording time. It was predominantly indicated pathway activity waveform and waveform of xylem feeding. After treatment of cyantraniliprole with recommended concentrations to tomato plants, EPG waveforms were recorded during 3 hours. Cyantraniliprole treatment showed longer time to first feeding xylem than untreated (P=0.043). It was showed shorter duration of first feeding xylem than untreated (P=0.017). And it was showed longer NP (non-probing) time than untreated. Consequently, It was supposed that cyantraniliprole was effect of anti-feeding or avoidance to B. tabaci.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.351-358
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• 2016

Consistent with a previous study on the brown planthopper Nilaparvata lugens (BPH) (Seo et al., 2009), we identified seven distinct EPG waveforms (np, L1, L2, L3, L4-a, L4-b, and L5) in adult female Laodelphax striatellus (SBPH) that fed on rice plants, by using the direct current electrical penetration graph (DC-EPG) system. The shape of waveforms and the pattern of occurrence of each waveform of SBPH were very similar to those of BPH. L3 and L4-a always occurred prior to L4-b. Periodical honeydew excretion was observed in L4-b only. Microsection observation following laser stylectomy revealed that the tips of SBPH stylets severed in L3, L4-a, and L4-b were commonly located in or near the phloem region of rice plants, but were located in the xylem in L5. Plant sap flowed from the stylets severed in L4-b only, and its main carbohydrate component was detected as sucrose by HPLC analysis. These results and the patterns of EPG waveform progress in SBPH suggested that feeding activities on rice plant tissue were relevant to each EPG waveform. L1 and L2 corresponded to the initiation of stylet penetration and stylet movement with salivation on the outside of the vascular bundle. L3 and L4-a were related to feeding activities within the phloem region in preparation for phloem sap ingestion. L4-b was closely associated with phloem sap ingestion, and L5 corresponded to xylem feeding behavior.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.194-204
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• 2016

The pear psylla, Cacopsylla pyricola, is a very small sap-feeding insect of many commercial pear varieties that could be considered the most serious insect pest of pear. Detailed information on plant penetration activities of the pear psylla is essential to study its feeding behavior used to evaluate resistant traits to chemical control. The application of the electrical penetration graph technique (EPG) could provide a relevant insight into the nature of this resistance. EPG waveforms of C. pyricola were characterized on the basis of amplitude, frequency, voltage level, and electrical origin. Feeding behaviors of C. pyricola were recorded and analyzed by EPG analysis. During EPG monitoring, waveform PA occurred at the start of stylet penetration of pear leaf epidermal cell. Waveform PB followed, in which stylet secreted saliva was observed. Waveforms PC1 and PC2 involved penetrating and sucking behaviors in parenchyma cells and vascular parenchyma, respectively. In addition, waveform PC1 represented salivation into bundle sheath cells and ingestion from parenchyma. Otherwise, behaviors of salivation into phloem and ingestion from phloem produced waveforms PE1 and PE2, respectively. On the other hand, ingestion from xylem tissues showed waveform PG. Among the feeding patterns of C. pyricola described above, phloem feeding patterns occurred most frequently, followed by xylem feeding and parenchyma penetration patterns in descending order.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.72-81
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• 2016

Feeding behaviors of the pear psylla, Cacopsylla pyricola, and their changing feeding behaviors were recorded and analyzed with an electrical penetration graph (EPG) analysis against 5 insecticides. And their mortality against insecticides were carried out in the laboratory. General feeding behavior patterns of C. pyricola were changed by insecticide treatments. Especially, the type and frequency of waveforms differently occurred depending on a sort of insecticides treated. Total duration of transition to waveform PE1 and phloem ingestion (waveform PE2) were significantly different between treatment and non-treatment of insecticides. When 5 different insecticides were treated on pear leaves, difference of feeding patterns were recorded. In case of treatment of benfuracarb, total duration of non-probes (waveform Np) was appeared higher than any other insecticide. However, when flonicamid and deltamethrin were treatment, total duration of stylet penetration (waveform PA) and xylem ingestion (waveform PG) were appeared higher than other insecticide, respectively. As results feeding behaviour of C. pyricola after treated insecticides with time-based consumed rate of C. pyricola, the rate of non-probe (waveform Np) was longer than start penetration (waveform PA), penetration and ingestion in parenchyma cells (waveform PC1+PC2), ingestion at phloem (waveform PD+PE1+PE2) and xylem (waveform PG). As result of direct spray treatment to C. pyricola, mortality of C. pyricola against imidacloprid was higher than any other insecticide on 24 hours after treatment. However, all of insecticides showed 100% mortality of after 48 hours. On the other hand, when 5 insecticides sprayed on the pear leaves and then C. pyricola located on the treated leaves, benfuracarb showed the most toxicity against C. pyricola among insecticides. These result was consistent with the EPG results that showed relatively longer total duration time of waveform Np (non-probes) by benfuracarb treatment.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.3243-3244
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• 2000

From ancient times, the diagnosis method of the oriental medicine has been performed by curing diseases by means of rectifying and adjusting the unbalance in the physiological function of the five viscera and the six bowels of a human body. Diseases have been diagnosed by the condition of blood circulation that cycles a human body through blood vessels by dint of the vitality of the heart. Based on such a systematic pulse diagnosis method, the article presents parameters that will be beneficial to clinical application on the basis of its analysis of the filtering for eliminating noises from pulse signals inputted from sensor group, the digital hardware dealing with signals necessary for recognition algorithm, and the structure of diagnosis algorithm and components of pulse waveform.

• Korean journal of applied entomology
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• v.46 no.3
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• pp.401-408
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• 2007

The feeding behaviors of 2 biotypes (type B and Q) of tobacco whitefly, Bemisia tobaci, were monitored using EPG technique on tomato and pepper plants treated 3 insecticides for controlling whiteflies, for examples, acetamiprid, spinosad and thiamethoxam. After treatment of three insecticides with recommended concentrations to tomato and pepper plants, EPG waveforms were recorded during 6 hours. The characteristic patterns of feeding behaviors investigated were as follows; time consumed by withdrawal of proboscis, total non-penetration time, total stylet pathway pattern time and total phloem feeding time. There was somewhat difference among 3 insecticides tested. As a result of investigation of total duration showed the stylet pathway activity due to the reaction against all tested insecticides, the Q biotype showed fewer time than those from the B biotype. The B biotype showed more frequent stylet pathway activity patterns during whole recording time and a shorter phloem ingestion time than those from the Q biotype. In result of prior up (non-penetration) time representing the reaction against the insecticide treated, the time of B biotype was more faster than that of the Q biotype, so it was considered that the B biotype was more sensitive to the tested insecticides. Therefore, our results revealed a clear difference in feeding behaviour between the B and Q biotypes of B. tabaci. Also, it was investigated that B biotype was susceptible to the 3 insecticides.