赤箭，為蘭科植物之中的一屬，其根部可做為中藥材使用，能治療頭痛、癲癇及高血壓等病狀，有極高的藥用及保健食用價值。赤箭雖為蘭科植物，但其細胞中並無任何葉綠素的存在，無法進行光合作用，必須透過與真菌的共生才能獲取足夠的養分，因此，瞭解赤箭與哪些真菌共生是非常重要的。本研究使用夏赤箭為題材，探索夏赤箭根部與周遭土壤中的真菌組成，並觀察是否有特定的真菌存在於夏赤箭之根部。我們與成功大學生命科學系宋皇模教授合作，採取了五株夏赤箭根部及其周圍土壤之DNA樣本，透過 primer 放大 28S rDNA的片段，最後利用Illumina 定序平台進行定序。為了鑑定序列所屬的物種(Taxonomy)，我們將序列比對到NCBI large subunit rRNA 的資料庫來決定序列之物種。另外為了比較各樣本間真菌菌落的差異，我們利用各樣本的序列資訊來進行菌落相似度之分析。結果顯示，所有夏赤箭根部之真菌組成均比土壤之真菌組成簡單。在所有夏赤箭根部的樣本中，Mycena species 為數量最多的真菌物種。相較之下，Mycena species只佔了土壤真菌一小部分。此外，我們也發現夏赤箭根部彼此之間的真菌組成比一株夏赤箭根部與其周遭土壤之間的真菌組成更相似，這意味著夏赤箭根部的真菌菌落主要並非由其周遭土壤之真菌菌落所決定，而是只有某些特定的真菌能夠在夏赤箭根部生長。最後，我們觀察到Mycena species 在夏赤箭根部真菌中所佔的比例也有差異，這彰顯了個體差異的存在。

Gastrodia is a plant genus in the Orchidaceae family. It has economic value because the rhizomes of Gastrodia are a prominent herbal medicine that can treat headache and hypertension. A previous study indicates that Gastrodia has no chlorophyll and relies on symbiotic fungi for obtaining nutrients. Therefore, to understand the relationship between Gastrodia and the symbiotic fungi is important. In this project, we probe the fungal community in Gastrodia flavilabella tubers and study whether specific fungi co-exist with the tubers. We collaborated with Dr. Huang-Mo Sung’s group, who collected five Gastrodia tuber samples and their surrounding soil. We extracted total DNAs from each sample and used a primer to amplify 28S rDNA sequences for Illumina sequencing. To determine the taxonomy of the reads, we aligned all reads to the NCBI large subunit rRNA references. We also used FastUniFrac to compare the fungal communities in the tubers and their surrounding soil. Our study showed that the fungal communities in all tuber samples were less complex than those in the soil. The most abundant fungi in the tubers were Mycena species. In contrast, Mycena species were only minorities in the soil. We also found that the fungal communities in all Gastrodia tubers were more similar to each other than to those in the surrounding soils, indicating a preference of certain fungi in Gastrodia flavilabella tubers. Despite the similar fungal preference, we found that the proportions of Mycena species in the tubers could be very different, indicating individual differences.

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