氟派瑞對不同生態位線蟲的致死率

The mortality of plant parasitic nematodes from different niches to fluopyram

氟派瑞(fluopyram)是抑制粒線體電子傳遞鏈上琥珀酸脫氫酶(succinate dehydrogenase)的殺真菌、殺線蟲藥劑，它可影響ATP生合成並導致線蟲癱瘓，國際上已用於防治多種線蟲，然而葉芽線蟲(Aphelenchoides spp.)未在其列。但葉芽線蟲為我國經濟重要性線蟲，危害水稻、山蘇及國蘭等重要作物。本研究以不同濃度氟派瑞處理根瘤線蟲(Meloidogyne spp.)、腎形線蟲(Rotylenchulus sp.)和葉芽線蟲紀錄其致死率。氟派瑞處理24小時後根瘤線蟲和水稻葉芽線蟲(A. besseyi)，在三種稀釋濃度下皆全數死亡；而A. bicaudatus有極少數的線蟲存活；而在腎形線蟲方面，藥劑稀釋濃度1500倍、3000倍、6000倍的自然死亡率分別為37.9%、30.3%、33.1%，不同藥劑稀釋濃度的自然死亡率之間未有顯著差異。氟派瑞對於根瘤線蟲和葉芽線蟲皆有明顯的致死效果，但腎形線蟲和極少數的A. bicaudatus卻仍可存活，表示不同線蟲屬與種間皆具有氟派瑞感受差異性。氟派瑞具有潛力用於防治不同的植物線蟲病害，但需考量線蟲感受度、施用方法、環境危害和作物藥害等方面，未來將進一步設計試驗來確認此藥劑用於防治水稻葉芽線蟲之可行性。

Fluopyram is a succinate dehydrogenase inhibitor (SDHI) fungicide that affects the synthesis of ATP and causes paralysis of nematodes. Fluopyram-based products are currently registered for many crops to mitigate root-knot nematodes. Although Aphelenchoides spp., which causes losses to rice, nest ferns, and orchids, are not listed as fluopyram-targeted nematodes, this genus has many economically important species in Taiwan. In this study, the mortality rates of three Meloidogyne spp., Rotylenchulus sp., and two Aphelenchoides spp. were recorded after treatments with 3 different concentrations of fluopyram. Meloidogyne spp. and A. besseyi all had a 100% mortality after being treated with different concentrations of fluopyram for 24 hr. However, A. bicaudatus had few nematodes survive. The Rotylenchulus sp. had mortality rates 37.9%, 30.3%, and 33.1% after treatments with the 1500X, 3000X, and 6000X fluopyram concentrations, respectively. Fluopyram was effective at killing Meloidogyne spp. and Aphelenchoides spp., but not Rotylenchulus sp., and a few A. bicaudatus individuals still survive. The results indicate that fluopyram sensitivity differs among different genera and species. For the field application, the nematodes' sensitivity to fluopyram, application methods, and phytotoxicity are factors that need to be considered. Further experiments are needed to confirm the feasibility of recommending fluopyram to control Aphelenchoides spp. on rice and other crops.