This study was performed to compare the host preference, survivorship and feeding behavior using EPG against ggot-mae-mi, Lycorma delicatula against seven plants such as Ailanthus altissima, Vitis vinifera, Malus pumila, Pyrus calleryana, Hibiscus syriacus, and Pinus densiflora. In host preference. L. delicatula was most preferred the Ailanthus altissima, Vitis vinifera and was not preferred the other plants. Survival rate of 3rd Nymph was recorded from Ailanthus altissima, Vitis vinifera as 15.0, and 15.4 days, respectively, it showed longest period. However, Malus pumila, Pyrus calleryana, Hibiscus syriacus, were survived within 6 days and Pinus densiflora was within 5 days. Moreover, L. delicatula was survived within 2 days to the three kinds of fruits. Ecdysis rate from 3rd to 4th nymph also high from Ailanthus altissima, Vitis vinifera as 63.3, 63.0 % and the order was followed as Malus pumila(17.7%) > Pyrus calleryana(9.3%) > Hibiscus syriacus(7.8%) > Pinus densiflora(5.9%). Especially, ecdysis rate was recorded 0% to the three kinds of fruits. Feeding behavior was analyzed using EPG and compared the differences their waveform from seven kinds of plants and three kinds of fruits. Non-probing time was short in host plants, reversely, Phloem-feeding time was recorded longer in Ailanthus altissima, Vitis vinifera as 45.7 and 13.7 min, respectively. And other plants and fruits were not showed feeding behavior.

This study was performed to investigate the feeding behavior of sweetpotato whitefly, Bemisia tabaci using the DC-EPG and the each developmental periods of biotype Q against nine varieties of red pepper. The result was showed that biotype Q did not feed and develop in the Nokkwang variety. In order to analyze the antifeedant, three feeding-preferred varieties (Cheongpungdaegun, Cheonyang, and Sannedeul) and non-preferred variety (Nokkwang) was tested for their sugar compounds using HPLC (ELSD Detector). The detected sugars were erythritol, xylose, xylitol, fructose, glucose, mannitol, and sucrose. In feeding-preferred varieties, the sugar such as erythritol, xylose, and xylitol were present at higher quantity than Nokkwang variety, however, fructose was existed lower quantity than Nokkwang variety. Subsequent bioassay for antifeedant activity, only xylitol showed repelled at lower concentration; however, attracted at higher concentration. Therefore, it is believed that xylitol may play a key role in the variety choice of red pepper by Q biotype of sweetpotato whitefly.

Biotype Q of Sweetpotato whitefly, Bemisia tabaci (Homoptera: Aleyrodidae) was raised in seven tomatoes and eight red pepper varieties; however, biotype B did not grow in red pepper varieties. Rokkusanmaru variety of tomato and Cheongpungdaegun variety of red pepper showed the highest susceptibility to biotype B and Q. HPLC (ELSD Detector) analysis showed that the presence of sugars such as erythritol, xylose, xylitol, fructose, glucose, mannitol, and sucrose in red pepper varieties; erythritol, xylose, fructose, glucose, and mannitol was in tomato varieties. Tomato varieties lacks xylitol and sucrose, which were present in the red pepper varieties. Subsequent bioassay with these two sugars, sucrose did not show significant difference between two biotypes; however, xylitol was showed only repellent effect against B biotype. Therefore, it seems that xylitol may play a key role in the selection of host plant by biotype B of sweetpotato whitefly.

Pine sawyer beetle, Monochamus saltuarius preferred the feed on fresh twig of Korean white pine trees (Pinus koraiensis) than one-year old and two-year twig. It means that the current twig is appropriate to increase the lifespan and reproduction of this insect. In a bioassay after fractionated the hexane layer from the water layer, the hexane layer did not show feeding response; however, the water layer was preferred in the order of fresh twig>one-year twig>two-year old twig. By HPLC analysis, we identified three kinds of sugar, namely, fructose, sucrose, glucose. The quantity of fructose was the highest in fresh twig followed by one-year and two-year old twig. In the preference test using each standard sample, the order was fructose>sucrose>glucose at 10, 30 μg/filterpaper, and fructose>sucrose >glucose at 50μg/filterpaper. From the above result, fructose plays an important role as a feeding stimulant for pine sawyer adult.