| Summary: | 碩士 === 國立嘉義大學 === 林產科學暨家具工程學系研究所 === 99 === The subtropical climate of Taiwan is warm and moist. It can make the silverfish to suits multiplication quietly, and caused rather more damage of cultural properties. Therefore, the necessary method to control the silverfish is prevention develop of silverfish. Nowadays, a lot of people pay more attention on environmental friendly and natural method to prevent the relic pests. Fruit extraction of china berry (Melia azedarach) and the oil was confirmed that those materials could control a lot of farming and forestry pests effectively. The aim of this research was to investigate the anti-pest effectiveness of Melia azedarach 's different parts extractives. We do analysis and evaluation on the gray silverfish's (Ctenolepisma longicaudata) repellent and mortality effect by extractives. The prevention tests was applied on anti-gray silverfish by natural plant extractives. In the repellent trials, we assess the activity of Melia azedarach 's different parts, the leaves and fruit are the optimal. But the both activity of the anti-gray silverfish have some difference between methanol and hot-water extractive. When the concentration of methanol extractives is 10 %, the repellency of anti-gray silverfish with leaf and fruit part of Melia azedarach are 87.3 % and 76.1 %. However, the fruit part of Melia azedarach had the highest repellent rate in the hot-water extractives (85.5 %) then the leaf part rate (75.9 %). Further, we have the leaf which contain activity to run separation by column chromatography, and found that the repellent activity was in the ethyl acetate soluble layer, the repellency achieve 85 % when concentration at 5 %. After runing the chromatography to detail separation, we know the most effective fraction was the third fraction（hexane : ethyl acetate = 85:15（%））. The repellency achieve more than half（59 %）when concentration at 0.1% and achieve 90 %, when concentration at 0.5%. We measured the brightness values and color values of the paper which is dipping with the extractives or not. In brightness values, changes smallest is the fruit of the hot water extractive; and the biggest change was the heartwood of the methanol extractive. In color values the changes smallest is the fruit of the hot water extractive. Based on the results, we know that the methanol and hot-water extractives of Melia azedarach provide a great potential of environmental-friendly chemical method to prevent the gray silverfish from damage of cultural properties.
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