微小害蟲顏色偏好之行為測試與開發應用

Abstract

微小害蟲如薊馬、粉蝨、蚜蟲等，因其體型細小而容易躲藏在植物的隱蔽處，使得化學藥劑不易達到其棲息處而減低化學防治的效用。而單獨使用化學防治法無法達到預期的防治效果，因此，田間常使用顏色誘引裝置誘集害蟲以增進防治的效果。顏色誘引裝置之原理是利用昆蟲對特定色光具有趨性，可吸引害蟲接近誘引物體進而達到捕捉及誘殺之效果。過去研究中使用者常以不同「顏色」來命名或區別誘引裝置表面，而人類與昆蟲的可見光譜不同，因此以人類所能感知的顏色來區辨昆蟲的趨色偏好行為，除了不符合學理依據外更容易誤導研究的結果。因此，本研究以誘引物體表面反射光譜作為昆蟲趨色偏好行為試驗的基礎，利用涵蓋不同光譜的色紙對昆蟲進行顏色偏好測試，並進行結果之比對以推算昆蟲之偏好光譜。在經過顏色偏好測試後，發現台灣花薊馬 (Frankliniella intonsa)偏好之波長範圍為508∼560 nm (4∼9日齡) 及 578∼700 nm (1∼3日齡)，與田間誘集以藍色光譜誘引蟲數較多之結果不同，而刺桐釉小蜂 (Quadrastichus erythrinae) 在田間及顏色偏好行為測試中則表現大致相似之顏色偏好行為。綜合實驗結果，本實驗所採用之顏色偏好檢測流程可應用於某些昆蟲上，而使用涵蓋不同反射光譜的色紙來檢測昆蟲之顏色偏好，更是比電生理記錄省時省力，為一大優點。但此流程適用於哪些類別的昆蟲，可能需要進一步實驗探討。

Tiny insects, such as thrips, whiteflies and aphids, are very small in their body size and can easily hide themselves in host plants, and therefore they can avoid the chemical sprays. Since the difficulty of chemical control to the hidden pests, color traps for luring the tiny pests have been used for a long tradition. Some insects can be attracted by particular wavelengths, so identifying the attractive wavelengths for inducing the color preference behavior of pests can reveal the critical factor for developing color traps. In the study, color papers with different wavelength range within the visible spectrum of insects are introduced to test color preference of the pests without the information of photoreceptor spectral sensitivity obtained from electrophysiological recordings in the compound eyes. After color paper preference test, it indicated that flower thrips, Frankliniella intonsa, prefer wavelength 508-560 nm (4-9-day-old) and 578-700 nm (1-3-day-old) than blue wavelengths which were preferred significantly in field trapping test. However, the erythrina eulophid wasps, Quadrastichus erythrinae, perform similar color preference in both field test and color paper preference test. According to the results, color paper preference test in the study is useful to test color preference of some insects but not suitable to every taxon. Light in natural environment is more complex than in laboratory. Thus, to test the color preference of specific insect, such as F. intonsa, it might process both field test and color paper preference test.