Fungal Clusters and Their Uniqueness in Geographically Segregated Wetlands: A Step Forward to Marsh Conservation for a Wealth of Future Fungal Resources

Abstract

Here, we investigated fungal microbiota in the understory root layer of representative wellconserved geographically segregated natural wetlands in the Korean Peninsula. We obtained 574,143 quality fungal sequences in total from soil samples in three wetlands, which were classified into 563 operational taxonomic units (OTU), 5 phyla, 84 genera. Soil texture, total nitrogen, organic carbon, pH, and electrical conductivity of soil were variable between geographical sites. We found significant differences in fungal phyla distribution and ratio, as well as genera variation and richness between the wetlands. Diversity was greater in the Jangdo islands wetland than in the other sites (Chao richness/Shannon/Simpson's for wetland of the Jangdo islands: 283/6.45/0.97 > wetland of the Mt. Gariwang primeval forest: 169/1.17/0.22 > wetland of the Hanbando geology: 145/4.85/0.91), and this variance corresponded to the confirmed number of fungal genera or OTUs (wetlands of Jangdo islands: 42/283 > of Mt. Gariwang primeval forest: 32/169 > of the Hanbando geology: 25/145). To assess the uniqueness of the understory root layer fungus taxa, we analyzed fungal genera distribution. We found that the percentage of fungal genera common to two or three wetland sites was relatively low at 32.3%, while fungal genera unique to each wetland site was 67.7% of the total number of identified fungal species. The Jangdo island wetland had higher fungal diversity than did the other sites and showed the highest level of uniqueness among fungal genera (Is. Jangdo wetland: 34.5% > wetland of Mt. Gariwang primeval forest: 28.6% > wetland of the Hanbando geology: 16.7%).

Geographical Isolation and Root-Associated Fungi in the Marine Terrains: A Step Toward Establishing a Strategy for Acquiring Unique Microbial Resources

“…Sedum takesimense is a representative native halophyte and has a long natural history of adaptation to ocean volcanoes [ 20 ]. As perennial plants [ 8 , 21 ], it flourishes in an evergreen community and forms a shrubbery zone able to stably interact with root-associated soil for a long period. ( Figure 1 ) [ 8 ].…”

“…As perennial plants [ 8 , 21 ], it flourishes in an evergreen community and forms a shrubbery zone able to stably interact with root-associated soil for a long period. ( Figure 1 ) [ 8 ]. Further, it forms a shrubbery zone in the narrow saxicoline zone of the soil, as a saxicolous plant [ 8 ].…”

“…Especially, symbiotic interactions between root layer-associated soil microbes and higher host plant species have been consistently studied. Its functionality has been demonstrated using large-scale screening: increase crop potential via growth promotion, increasing their resistance to environmental stress, and protecting them from environments where diseases and natural changes are severe [5][6][7][8].…”

“…Although these methods can theoretically reveal interactions between microorganisms and host plants, certain limitations have been noted, particularly concerning the diversity of bio-asset [ 1 , 3 ]. Due to an increasing number of studies focused on understanding functionalities, taxonomic positions of secured culture collection strains are gradually becoming nonspecific [ 8 ]. In fact, many studies do not present taxonomical uniqueness.…”

“…Meanwhile, although it has been reported that unique beneficial microorganisms can be discovered in special natural habitats, this will one day become challenged, as there is an inherent limit to the geographical diversity within any given nation [ 8 ]. Thus, if the differentiation of a fungal community is identified within special environments (particularly geographically isolated ones), the concept of geographical isolation itself will increase the potential to secure unique microbial species or improve diversity, providing another strategy to ensure the identification of diverse and unique microbial resources [ 3 , 8 ]. However, geographic isolation does not refer to only physical segregation, but may also include temporal concepts.…”