Search Results (3)

Thuja sutchuenensis Franch., an endangered species sparsely distributed in the mountainous and arid regions of southwest China, faces the critical challenge of adapting to these harsh conditions. Understanding the plant’s strategies for survival and the precise roles played by soil fungal communities in this adaptation remains an area of limited knowledge. Our investigation centers on the fungal communities associated with T. sutchuenensis and their interactions with soil water content. Notably, we identified unique fungal communities in the low soil moisture group, and these communities exhibited lower coverage but higher phylogenetic diversity (PD), Chao1, and Shannon indices compared to other groups. Network analysis revealed a modular structure within the fungal communities, with key hub nodes identified, particularly in the arid group. This group demonstrated higher levels of soil saprotrophs and ectomycorrhizal fungi and a reduced presence of plant pathogens. Linear discriminant analysis highlighted the significance of genera such as Russula, Myxotrichaceae, and Sebacina, emphasizing their roles in supporting the plant in arid environments. Random forest analysis indicated that soil moisture content emerged as the primary driver in determining fungal composition and diversity and contributed to the variables of several fungal genera. Collectively, this study provides valuable insights into the fungal communities associated with T. sutchuenensis, shedding light on their adaptation to extreme arid conditions. Full article

The protection of endangered species is a hot topic for scholars worldwide, and interspecific association and community stability analysis are important methods with which to explore the structure and function of the endangered species community. Thuja sutchuenensis Franch. is an endangered species; however, studies on the T. sutchuenensis community remain insufficient. Here, based on the data of the plot survey of the T. sutchuenensis community in the Ta-pa Mountains and Xuebao Mountains, we analyzed the interspecific associations, niche width, and niche overlap of major species in the arborous and shrub layers, as well as community stability. The results showed that the overall interspecies association between the species of the arbor layer was non-significantly negatively associated, while the shrub layer was non-significantly positively associated. The Chi-square test results showed that the species pairs without interspecific association in the arbor layer and the shrub layer were much higher than those with significant interspecific association; in other words, the interspecific association of species in the T. sutchuenensis community was loose. The results of interspecific association coefficient analysis showed that the number of negatively associated species pairs was significantly higher than that of positive association species pairs, but Pearson’s correlation coefficient and Morisita’s niche overlap index analysis showed that the degree of competition between species in the community was small. In the arbor layer, the niche width of T. sutchuenensis was the widest, while in the shrub layer, the niche width of T. sutchuenensis was relatively high, indicating that T. sutchuenensis had a strong ability to adapt to the environment and use available resources. In addition, the intersection point of community stability (32.11, 67.89) in the vegetative community of T. sutchuenensis suggested that the community displayed a better stability. The survival strategy of T. sutchuenensis is based on its strong adaptability to the harsh environment to escape the competition among species, and this knowledge can provide a reference for the protection and restoration of endangered species. Full article

Thuja sutchuenensis Franch. is a critically endangered plant endemic to the North-East Chongqing, China. Genetic variation was studied to assess the distribution of genetic diversity within and among seven populations from the single remnant locations, using inter-simple sequence repeat (ISSR) markers. A total of 15 primers generated 310 well defined bands, with an average of 20.7 bands per primer. The seven populations revealed a relatively high level of genetic diversity in the species. The percentage of polymorphic bands, Nei’s gene diversity and Shannon’s information index at the population and species level were 76.1%, 0.155, 0.252 and 100%, 0.165, 0.295, respectively. A low level of genetic differentiation among populations (G_ST = 0.102), in line with the results of Analyses of Molecular Variance (AMOVA), and a high level of gene flow (N_m = 4.407) were observed. Both the Unweighted Pair Group Method with Arithmatic Mean (UPGMA) cluster analysis and Principal Coordinates Analysis (PCoA) supported the grouping of all seven populations into two groups. In addition, Mantel test revealed no significant correlation between genetic and geographical distances (r = 0.329, p = 0.100). The low genetic differentiation among populations implies that the conservation efforts should aim to preserve all the extant populations of this endangered species. Full article