Eliminating the Biting Midge Forcipomyia Taiwana (Diptera: Ceratopogonidae) Larval Food Resource Algae, Cyanobacteria and Chlorella sp. (Chlorocaccales: Chlorellaceae) by Bactericide to Evaluate the Inhibition Effect in the Laboratory and Applying in the Field

[[abstract]]為了降低台灣鋏蠓在台灣造成的肆虐危害，本研究針對滅除其幼蟲食物（藻類）進行研究，採用不同濃度殺菌劑於實驗室與野外進行抑制藻類生長之試驗。本實驗使用葉綠素螢光（chlorophyll fluorescence）分析儀測得藻類的葉綠素螢光參數Fv／Fm值，藉此此值大小判別藻類生長是否受到抑制。首先於實驗室中進行不同濃度殺菌劑抑制兩種懸浮藻的試驗，結果顯示殺菌劑對此兩種懸浮藻液的抑制效果都達顯著差異。對於藍綠藻（Gloeothece sp.）的生長抑制，當殺菌劑於濃度20ppm時，即達顯著差異（p<0.05）；當殺菌劑濃度在20-400ppm下，抑制藍綠藻生長都有極佳之效果（p<0.01）。小球藻（Chiarella sp.）在殺菌劑於濃度60ppm下，其抑制生長效果達顯著差異（p<0.05）；當殺菌劑濃度在60－400ppm下，抑制小球藻生長都有極佳之效果（p<0.01）。就實驗室中抑制藻塊生長試驗，殺菌劑濃度在80ppm下，抑制藻塊生長就能達顯著差異（p<0.05）；當殺菌劑濃度在80－400ppm下，抑制藻塊生長都有極佳之效果（p<0.01）。另外，為了在未來防治上有效運用，亦進行殺菌劑抑制野外藻類生長試驗，結果發現殺菌劑需要在400ppm濃度以上，以及需要連續4天或以上施灑藥劑，即可達到有效抑制藻類生長（p<0.05）。[[abstract]]To reduce the damage and plague caused by Forcipomyia taiwana in Taiwan, this study focus on the control the larval food, algae, of Forcipomyia taiwana. This study employs different bactericide concentrations to test the inhibition on the algae growth both in laboratory and in the field. This experiment uses Diving-PAM to measure the algae chlorophyll fluorescence (Fv/Fm), and then analyzes the acquired values to determine the inhibition of algae growth. Firstly, cultivating suspension algae in the laboratory and conducting the inhibition experiments using different bactericide concentrations. The results show that the bactericide has remarkable effects on inhibiting the growth of the two suspension algae. The experiment revealed that the bactericide concentration of 20 ppm performed obvious inhibition on the Gloeothece sp. growth (p<0.05), and the bactericide concentration of 20-400 ppm significantly inhibited the Gloeothece sp. growth (p<0.01). The results showed that the bactericide concentration of 60 ppm performed obvious inhibition on the Chlorella sp. growth (p<0.05), and the bactericide concentration of 60-400 ppm significantly inhibited the Chlorella sp. growth (p <0.01). In laboratory, the experiment revealed that the bactericide concentration of 80 ppm performed obvious inhibition on the algae block growth (p <0.05), and the bactericide concentration of 80-400 ppm significantly inhibited the algae block growth (p<0.01). Furthermore, we tests bactericide inhibitory effect on algae in the field. The results revealed that the bactericide concentration we higher than 400 ppm, and sprayed 24 hours interval and test, more than 96 hours it significantly inhibit the growth of algae (p