赤箭為特殊的無葉綠素蘭科植物，須依賴共生真菌提供養分來生存，因此我們預期赤箭的空間分布會受到環境中真菌種類的限制。雖然有這層限制，卻有部分赤箭能生長於不同環境中。基於赤箭對真菌的依賴性，我們推測能適應不同的環境真菌組成最有可能與赤箭能否廣泛分佈有關。在過去僅發現分布較侷限且稀有的赤箭具有特異共生的單一優勢共生真菌，卻沒有關於廣泛分佈赤箭相關的真菌研究。於本次研究中，我們取廣泛分佈的爪哇赤箭與稀有分布的夏赤箭，藉由Illumina定序其根部以及周圍土壤中的所有28S DNA，由此定序資料做物種鑑定與樣本間真菌組成差異的比較。我們使用28S定序資料比對回NCBI LSU資料庫後，鑑定出夏赤箭植株中以Mycena為優勢物種；與此相對，爪哇赤箭植株則以多樣的真菌存在於根內為特徵，且沒有明顯的優勢物種。爪哇赤箭植株的多樣性皆高於夏赤箭。於進一步追蹤後，我們證實爪哇赤箭根部內的真菌菌相會受到其周圍土壤真菌所影響，且相對於夏赤箭根部與土壤真菌組成而言，我們發現爪哇赤箭的根部與土壤的真菌菌組成關係確實相對類似。這些證據說明爪哇赤箭能夠讓更多土壤真菌較無限制的進入根內，並且對於真菌的選擇較不挑剔。這些現象也能解釋兩種赤箭分布範圍的差異狀況。

Gastrodia is a special chlorophyll lacking plant and relies on specific symbiotic fungi for nutrients. Therefore, environmental fungi can limit the spatial distribution of Gastrodia. Under this constraint, however, some Gastrodia species are still widely distributed. We hypothesize that symbiotic fungal composition is an important factor for a Gastrodia specie to be widespread or endemic. It has been reported that only few specific fungi are present in endemic Gastrodia species, e.g., elata and flavilabella. However, there is still no report about fungi in widespread Gastrodia species. In this study, we collected two Gastrodia species, widespread Gastrodia javanica and endemic Gastrodia flavilabella. After extracting total DNAs from tubers and soils of the two Gastrodia species, 28S rDNA sequencing was applied for species identification. We found that Mycena dominated in the tubers of G. flavilabella while different fungi lived in the tubers of G. javanica. Consistently, fungal diversity was higher in the G. javanica tubers than in the G. flavilabella tubers. In addition, dominating fungi in different G. javanica individuals were different. This suggests that the widespread G. javanica is less limited by specific symbiotic fungi.

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