臺灣針葉五木具有生態保育、林業生產、經濟利用等特殊價值，五樹種在苗木培育及苗期病害管理為林業苗圃中的重要工作，為釐清寄生性藻斑菌對貴重針五木在苗期植株之影響，本研究於國立臺灣大學生物資源暨農學院實驗林管理處溪頭苗圃內進行藻斑（algal spots）寄主植物、危害及發生生態之調查，以提供後續苗木管理之參考。透過解剖、光學及掃描式電子顯微鏡觀察植體上之藻類斑點，基於植物病變徵狀、藻類形態特徵及侵入植體型式，將其鑑定為2種寄生性藻類，包含綠色頭孢藻（Cephaleuros virescens）、寄生頭孢藻（C. parasiticus）及3種葉楯藻屬（Phycopeltis）之附生性藻類（P. arundinacea、P. amboinensis、Phycopeltis sp.），分別發生於14種植物的地上部植體。其中，臺灣杉（Taiwania cryptomerioides）、南洋紅豆杉（Taxus sumatrana）、巒大杉（Cunninghamia konishii）、臺灣肖楠（Calocedrus macrolepis var.formosana）、紅檜（Chamaecyparis formosensis）及臺灣扁柏（Ch. obtusa var. formosana）等6個分類群（包含種及變種）為綠色頭孢藻的臺灣新紀錄寄主，且柏科（Cupressaceae）亦為頭孢藻寄主的新紀錄科別，研究統計綠色頭孢藻於臺灣之寄主範圍共計95科410個植物分類群。

The five precious conifers of Taiwan have special values such as ecological conservation, forestry production, and economic utilization. Therefore, seedling cultivation and seedling disease management of these five taxa are important tasks for forestry nurseries. To clarify the effect of parasitic algal plaque fungus on the plants at the seedling stage, this study surveyed the host plants, damage, and occurrence ecology of algal spots on seedlings of the five species in the Xitou Nursery of the Experimental Forest of National Taiwan University to provide a reference for subsequent seedling management. Based on the appearance of the lesions, algal morphology, and invasion types using the dissecting, light, and scanning electron microscopes, two parasitic algae and three epiphytic algae were identified as Cephaleuros virescens, C. parasiticus, Phycopeltis arundinacea, P. amboinensis, and Phycopeltis sp. on 14 plants. Among these plants, six taxa (including species and variety) were new records as hosts of C. virescens in Taiwan, such as Taiwania cryptomerioides, Taxus sumatrana, Cunninghamia konishii, Calocedrus macrolepis var. formosana, Chamaecyparis formosensis, Ch. obtusa var. formosana. In addition, Cupressaceae was a newly recorded family of hosts for Cephaleuros in Taiwan. According to the statistics provided by this study, the host range of C. virescens in Taiwan reached a total of 410 plant taxa in 95 families.