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Leaves of Magnolia liliifera were selected to evaluate fungal diversity, and succession of fungi during leaf decomposition, and the effect of baiting on fungal diversity. The leaf samples were from Doi Suthep-Pui National Park, Chiang Mai, Thailand. Twenty-three taxa were identified on senescent leaves of M. liliifera during the decay process. Distinct fungal communities were observed with the dominant species on the leaves being different at each succession stage. The most abundant fungal species were Hyponectria sp. 1 (on 60% of leaves), Volutella sp. 1 (60%), Gliocladium sp. 3 (37.1%), Corynespora cassiicola (34.3%), Bionectria ochroleuca (25.7%), Cylindrocladium floridanum (22.8%), Phaeosphaeria sp. (17.1%), Dactylaria longidentata (11.4%) and Lasiosphaeria sp. (11.4%). Leaf bait trials did not show any noticeable effect on fungal diversity when either the upper or lower leaf surface was adjacent to the forest floor. Highest fungal diversity on leaves of M. liliifera occurred between day 4 and 40, with most species being present on day 40. On day 56, leaves were found to be skeletonized, and the fungal communities had decreased in number.

This study investigated the communities of fungi on Magnolia liliifera wood in terrestrial and freshwater habitats in northern Thailand. Freshly fallen samples of M. liliifera wood were collected from the forest floor, oven dried, and then placed in the stream or adjacent to the stream on the forest floor as baits. The samples were collected and examined after 3 and 6 months of submersion and periodically over 29 months from the forest floor. Thirty-seven species of lignicolous fungi were discovered from 50 bait samples of wood submerged in the stream. Fungi obtained from submerged baits were compared with those found on wood of M. liliifera in terrestrial habitats (both naturally terrestrial and terrestrial baits). The fungal communities on wood in freshwater were distinct from those in the terrestrial habitat. Seventeen species of fungi overlapped between freshwater and terrestrial habitats, but only five out of 234 species overlapped between all habitats (freshwater, natural terrestrial and terrestrial bait). Corynespora cassiicola (60% frequency of occurrence) was the most common taxon found on natural terrestrial samples, while Lasiodiplodia theobromae (43% frequency of occurrence) was the dominant species from terrestrial baits. Candelabrum brocchiatum (26%) was the most common species from submerged baits. The common genera of fungi obtained from submerged baits were similar to those reported in other submerged wood studies.

School of Science, Mae Fah Luang University, Thasud, Chiang Rai 57100, Thailand Institute of Excellence in Fungal Research, Mae Fah Luang University, 57100 Chiang Rai, Thailand School of Cosmetic Science, Mae Fah Luang University, Thasud, Chiang Rai 57100, Thailand Faculty of Science and Technology, Pibulsongkram Rajabhat University, Phitsanulok 65000, Thailand 5 Landcare Research, Private Bag 92170, Auckland, New Zealand

The diversity of endophytic and saprobic fungi from Magnolia liliifera leaves were observed and analyzed to establish relationships. Nine endophytes were morphologically and phylogenetically similar to the saprobes; Colletotrichum gloeosporioides, Colletotrichum sp. 2, Corynespora cassiicola, Fusarium sp. 1, Guignardia mangiferae, Leptosphaeria sp., Phomopsis sp. 2, Phomopsis sp. 6, and Phomopsis sp. 10. The endophytes were found to produce the same degrading enzymes as their saprobic counterparts. The isoform of β-mannanase produced from each of endophyte and saprobe counterparts were similar. Fungal succession and enzyme production patterns during leaf decomposition were correlated. The occurrence of saprobes was found to be related to the enzymes that the fungi produce. The study provides further compelling evidence that endophytes can switch lifestyle to saprobes.

Fungal endophytes and saprotrophs generally play an important ecological role within plant tissues and dead plant material. Several reports based solely on morphological observations have postulated that there is an intimate link between endophytes and saprotrophs. This study aims to provide valuable insight as to whether some endophytic fungi manifest themselves as saprotrophs upon host decay. Ribosomal DNA-based sequence comparison and phylogenetic relationships from 99 fungal isolates (endophytes, mycelia sterilia, and saprotrophs) recovered from leaves and twigs of Magnolia liliifera were investigated in this study. Molecular data suggest there are fungal taxa that possibly exist as endophytes and saprotrophs. Isolates of Colletotrichum, Fusarium, Guignardia, and Phomopsis, which are common plant endophytes, have high sequence similarity and are phylogenetically related to their saprotrophic counterparts. This provides evidence to suggest that some endophytic species change their ecological strategies and adopt a saprotrophic lifestyle. The implication of these findings on fungal biodiversity and host specificity is also discussed.