由Cercospora tetragoniae引起之番杏葉斑病初報

Leaf spot of Tetragonia tetragonioides caused by Cercospora tetragoniae

2019年5月於花蓮縣吉安鄉蔬菜圃之番杏葉片產生大量深褐色圓形病斑，病斑中央呈現灰白色點狀，病斑周圍經常伴有黃色暈環，藉由組織分離獲得病原菌，經由病徵及菌株形態並佐以分子親緣分析，最後以柯霍氏法則驗證，確認該病害係由Cercospora tetragoniae（Speg.）Siemaszko於番杏上造成之葉斑病，為臺灣產尾子菌類真菌之一新紀錄種，研究菌株（FU31220）已保存於臺灣生物資源保存及研究中心（BCRC），並首度於基因序列資料庫登錄C. tetragoniae之基因序列。

In May 2019, in the vegetable garden of Ji'an Township, Hualien County, large amounts of dark brown circular spots appeared on the leaves of Tetragonia tetragonioides. These lesions exhibited grayish-white spots at the centers and were often surrounded by yellowish halos. The pathogen was isolated from the infected tissues. Through the symptoms and the pathogen morphological characteristics and molecular phylogeny, the leaf spot disease of T. tetragonioides was confirmed to be caused by Cercospora tetragoniae (Speg.) Siemaszko. This discovery represents a new record species of cercosporoid fungi in Taiwan. The strain (FU31220) has been preserved at the Taiwan Bioresource Collection and Research Center, (BCRC) and gene sequences of C. tetragoniae have been deposited into the genetic sequence database for the first time in the world.