Fungal communities on decaying fronds of Livistona australis, Oraniopsis appendiculata (Australia), Arenga engleri, Livistona chinensis (Hong Kong), Arenga undulatifolia, Salacca affinis, and Oncosperma horridum (Brunei) were examined for fungi. In all, 288 different taxa were identified. The fungal communities on different frond parts (i.e. leaves, rachis-tips, mid-rachides and rachis-bases), on different hosts, at different sampling sites, at different stages of decay, and in different seasons were compared.
Fungal species compositions were distinct on different hosts and at different sites. Three-dimensional correspondence analysis resulted in: (a) three clusters corresponding to distinct communities on samples in Australia, Brunei and Hong Kong; (b) fungi on palms of the same genera (Arenga undulatifolia and A. engleri; Livistona australis and L. chinensis) at different sites, being more coherent than on palms of different genera at different sites; (c) fungi on palms of different genera at the same site being more coherent than on palms of the same genera at different sites. Fungal taxa on the same palm genus or species in different sampling sites were significantly different. Evidence for host specificity and fungal recurrence on different hosts and frond parts were found. No evidence of seasonal patterns of fungal communities was found on the palm hosts. Only 10% of the fungi were common to all three palm species studied in Brunei and 17% were common to the two palm species at Victoria Peak, Hong Kong.
Significant differences were found in the fungal communities colonising each of the different frond parts (leaves, rachis-tips, mid-rachides and rachis-bases). The greatest differences in most palms were found between the leaves and rachides.
When investigating fungal diversity it is recommended to examine a combination of naturally occurring fronds and frond baits throughout the decomposition process. Since a large number of forests, plant species and even types of plant tissues have yet to be explored by mycologists, we predict that there are an incredibly large number of fungi on these unexplored substrata.
This study has confirmed that fungi on palms are very diverse and suggests some reasons for this. The data has important implications towards future biodiversity studies and estimates of global fungal numbers. Future studies and estimations must reflect and incorporate these results.