Flower endophytic fungi of Geodorum densiflorum endangered orchid

Abstract

Geodorum densiflorum is an ornamental and medicinally important orchid. The medicinal metabolites are produced by endophytic fungi associated with orchid tissue, particularly flowers. However, there is no report of the endophytic fungi from the G. densiflorum flowers. This research aimed to study the endophytic fungi from different parts of G. densiflorum flower. Fungal isolation was carried out from sepal, petal, labium, stigma, and anther using surface sterilization method. The fungi were identified by combining morphological and molecular characteristics of ITS rDNA region. The results showed that each flower organ had different species of endophytic fungi. A total of seven species of endophytic fungi were obtained; four species were successfully identified by molecular identification and three species based on morphology. The four species, namely Hypomontagnella barbarensis, Aspergillus oryzae, Curvularia pseudobranchyspora, and Nigrospora chinensis, while the three species, namely Gonatobotrys sp., Humicola sp., Aspergillus section Nigri. The labium inhabited by Curvularia pseudobranchyspora, Nigrospora chinensis, Aspergillus section Nigri. Three species isolated from petals, namely Hypomontagnella barbarensis, Gonatobotrys sp., and Aspergillus oryzae. The sepal is inhabited by Humicola sp. There were no endophytic fungi in stigma and anther. This indicates that each flower part is a unique habitat of endophytic fungi.