Abstract China-fir (Cunninghamia lanceolata) is an economically important conifer which is mainly used as construction lumber. Scolytids are key forestry pests and some species are also listed as quarantine pests. In 2002, they were the most likely cause for the dying of China-fir trees in central Taiwan. Scolytids are attracted by the volatile chemicals released from trees or wood. Thus in this study we used 12-unit Lindgren multiple funnel traps baited with α-pinene and 95% ethanol to investigate the scolytid species in the China-fir plantation. The trapping took place from June 2004 to May 2005 in the Nei-Mou-Pu Tract of the NTU Experimental Forest. A total of 25 traps were set, and the results showed that 40,366 scolytids belonging to 72 species, 30 genera, and 9 tribes were collected. These 72 scolytid species included 2 endemic species, 44 recorded species, 5 near species and 21 possibly new species (9 species had only one specimen each) in Taiwan. The number of Hypothenemus eruditus (Westwood), Xyleborus affinis (Eichhoff), Phloeosinus pertuberculatus (Eggers), Xylosandrus mancus (Blandford) and Scolytoplatypus pubescens (Hagedorn) amounted to 37, 24.4, 7.8, 7.6 and 6.4%, respectively. They were the top five species of attracted scolytids in the collection. Three 1.5-meter lengths of dead wood were collected in each lot, and each wood was cut into 3 pieces to breed and collect the insects in these woods. This experiment was repeated three times for comparison with the scolytids in the traps. P. pertuberculatus was the third most plentiful species trapped, but it was the most abundant species (46.2% of all scolytid beetles) found in the 9 pieces of wood of the experiment. This investigation provides the fundamental data on scolytids in Taiwan, and how to protect against scolytids in China-fir plantations in the future.
摘要 杉木 (Cunninghamia lanceolata) 是重要的建築木材，為具經濟重要性的針葉植物，而小蠹蟲為林木的重要經濟害蟲，在 2002 年曾被認為是造成台灣中部多處杉木萎凋枯死的元兇。因小蠹蟲受林木所釋出的氣味吸引，本試驗利用α-蒎烯 (α-pinene) 及乙醇 (95% ethanol) 兩種混合誘引劑以林根氏多層誘蟲器 (Lindgren multiple funnel trap) 於台大實驗林的內茅埔營林區共設 25 個陷阱，調查杉木人工林中的小蠹蟲種類，於 2004 年 6 月至 2005 年 5 月一年期間，總計誘得 40,366 隻小蠹蟲，分別隸屬於 9 族 30 屬 72 種 (其中 18 種僅誘集到 1 隻)，包括 44 種已紀錄種，2 種特有種，5 種疑似已知種及 21 種 (9 種僅捕獲 1 隻) 疑似新種。在數量方面以 Hypothenemus eruditus (Westwood)、Xyleborus affinis (Eichhoff)、Phloeosinus pertuberculatus (Eggers)、Xylosandrus mancus (Blandford) 及 Scolytoplatypus pubescens (Hagedorn) 等 5 種小蠹蟲的數量最多，分別佔誘集總數之 37、24.4、7.8、7.6 及 6.4%。本研究還收集樣區內之枯倒杉木，進行了段木內小蠹蟲種類調查；結果顯示以 P. pertuberculatus 所佔數量最多，約 46.2% (在陷阱調查中其數量位居第三)。此等調查除建立本國杉木林中小蠹蟲之基本資料外，亦可供未來防治杉木林中小蠹蟲之參考。
| Key words: Scolytinae, China-fir, Lindgren multiple funnel traps, NTU Experimental Forest, lures | | 關鍵詞: 小蠹蟲、杉木、林根氏多層誘蟲器、台大實驗林、誘引劑。 |
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