平伏莖白花菜（Cleome rutidosperma）於臺灣果園之族群分布及其簇葉病發生之研究

Study of Distribution of Fringed Spiderflower (Cleome rutidosperma) in Orchards of Taiwan and Witches'-Broom Disease Caused by Phytoplasma

戴肇鋒(Chao-Feng Tai) ； 白瓊專(Chyong-Juan Bor) ； 李祈益(Chi-Yi Li)

《臺灣農藥科學》 12期 (2022/06) Pp. 61-78

https://doi.org/10.6671/TPS.202206_(12).04

摘要

平伏莖白花菜（Cleome rutidosperma）是一種源自非洲熱帶地區之植物，現已常見於亞洲溫暖區域，近年來已成為臺灣新的歸化物種。雜草除了與作物競爭營養外也可為作物的輪替寄主。在2017至2018年間的臺灣西部果園雜草調查中發現，平伏莖白花菜共於暖季出現於57田區，占總調查40.1%，其中優勢種比例為40.4%；冷季出現於43田區，占總調查32.6%，其中優勢種比重為58.1%，此結果顯示平伏莖白花菜已是臺灣西部果園中高潛力之入侵物種。本團隊調查期間於雲林、臺南與高雄共採集6株疑似帶有簇葉（witches' broom）病徵的植株，並藉由穿透式電子顯微鏡觀察確認其體內含有植物菌質體（phytoplasma）。以P1/TINT引子對使用聚合酶連鎖反應檢測雲林（TWY1）與高雄（TWK1）菌系，各增幅出1.6K之片段產物，與GenBank比對不同菌系之16S rRNA片段，確認其為16SrII-A亞群之菌系。以平原菟絲子（Cuscuta campestris）系統進行傳菌試驗，觀察平伏莖白花菜的發病進程，包含枝條增生（proliferation）、花器葉片化（phyllody）、嚴重簇葉等。本研究結論為平伏莖白花菜目前為果園優勢種雜草，並有可能成為植物菌質體病害的輪替寄主，須重視其於田間的雜草管理。

關鍵字

平伏莖白花菜 ； 植物菌質體 ； 簇葉病 ； 族群分布

並列摘要

Fringed spiderflower (Cleome rutidosperma), which originated in tropical Africa and is now common in warmer regions of Asia, has become a naturalized plant species in Taiwan in recent years. Weeds compete for nutrition against crops and also serve as alternative hosts for many diseases. A survey of weed species targeting 132 orchards in western Taiwan from August 2017 to August 2018 found that fringed spiderflower appeared in 57 orchards (40.1%) during warmer seasons, and it became dominant, which is defined as a weed species covering over 5% of the ground, in 23 of the 57 orchards (40.4%). During colder seasons, the plant also appeared in 43 orchards (32.6%) and became dominant in 25 of the 43 orchards (58.1%). The findings suggest that fringed spiderflower has high potential to become dominant now that it has successfully invaded western Taiwan. During this investigation, six plants showing symptoms of witches' broom were collected from Yunlin, Tainan, and Kaohsiung and were also confirmed to be infected with phytoplasmas following testing with the TEM technique. The sequence of a 1.6 kb PCR product amplified with a P1/TINT primer set from the samples collected from both Kaohsiung and Yunlin was identical to the 16S rRNA sequence of 16SrII-A subgroup phytoplasmas. Analysis with a dodder transmission system confirmed that the symptoms of witches' broom found in the fringed spiderflowers were indeed caused by phytoplasma. Thus, this study sheds light on the potential for fringed spiderflower to be an alternative host of phytoplasma and stresses the importance of weed management.

並列關鍵字

Cleome rutidosperma ； phytoplasma ； witches'-broom disease ； population distribution