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Several studies have been conducted on the distribution of carbon (C) and nitrogen (N) in plant, however, there has been rare data linking Ecological Stoichiometry to plant invasion success, especially in a low-N environment. Accordingly, an experiment in this study was performed to explore the nutrition distribution and stoichiometry among various organs in plant, contributing to plant invasion. According to the results of this study, both invasive and native species exhibited a higher C, N concentration and lower C/N ratio in their leaf compared with stem and root overall (p

Supports for the molecular evolution of host pathogen interactions on enemy release hypothesis are rare. According to the theory of plant immunity and the coevolution of hosts and pathogens, we hypothesized that the evolutionary rate (d(N)/d(S)) of resistance genes (R-genes) in invasive plants would be greater than in non-invasive plants, assuming that based on the enemy release hypothesis, the former would suffer less selection stress from co-evolutionary specialist pathogens. To test our hypothesis, we isolated and analyzed the conserved nucleotide-binding sites (NBS) of resistance gene analogues (RGAs) of an invasive weed, Wedelia trilobata (WTRGA). We then used the information in GenBank to compare the d(N)/d(S) of the NBS R-gene/RGAs in invasive and homologous non-invasive plants. Three W. trilobata NBS RGA sequences were obtained, belonging to the Toll/Interleukin-1 receptor (TIR) (WTRGA1 and WTRGA2) and non-TIR subclasses (WTRGA3). Compared with the homologous non-invasive plants, the invasive plants showed a significantly greater d(N)/d(S) for TIR NBS R-gene/RGAs (p < 0.0001), supporting our hypothesis. Future research should include an examination of R-genes/RGAs from more invasive plants on a population level to understand diversity and R-gene functions in invasive plant species, as well as to explore how disease resistance allows plants to adapt to changing pathogen stresses. (C) 2015 Elsevier Ltd. All rights reserved.

To understand the genetic differentiation of the medicinal fungus Shiraia bambusicola , the genetic diversity of 107 individuals from eight populations collected from Jiangsu, Anhui and Zhejiang provinces were studied using inter-simple sequence repeat (ISSR) analysis. The results revealed that the 11 employed primers produced a total of 241 ISSR loci, of which 240 loci (PPB = 99.6%) were polymorphic. Both Nei's gene diversity indexes and Shannon's gene diversity indexes showed that the genetic differentiation of S. bambusicola primarily occurred within the populations. AMOVA revealed that the variation among populations was 40.0%, and the variation within populations was 60.0%. The results of an unweighted pair group method arithmetic average (UPGMA) analysis and a principal coordinate analysis (PCA) revealed that the populations with minimal geographic separations frequently exhibited regional characteristics. These findings revealed that the relationship between sibship and geographical distribution was intensive.