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Benzimidazoles anthelmintics, which enter into environment primarily through excretion in the feces or urine of treated animals, can affect various organisms and disrupt ecosystem balance. The present study was designed to test the phytotoxicity and biotransformation of the three benzimidazole anthelmintics albendazole (ABZ), fenbendazole (FBZ) and flubendazole (FLU) in the harebell (Campanula rotundifolia). This meadow plant commonly grows in pastures and comes into contact with anthelmintics through the excrements of treated animals. Suspensions of harebell cells in culture medium were used as an in vitro model system. ABZ, FLU and FBZ were not found to be toxic for harebell cells, which were able to metabolize ABZ, FLU and FBZ via the formation of a wide scale of metabolites. Ultrahigh-performance liquid chromatography coupled with high mass accuracy tandem mass spectrometry (UHPLC-MS/MS) led to the identification of 24, 18 and 29 metabolites of ABZ, FLU and FBZ, respectively. Several novel metabolites were identified for the first time. Based on the obtained results, the schemes of the metabolic pathways of these anthelmintics were proposed. Most of these metabolites can be considered deactivation products, but a substantial portion of them may readily be decomposed to biologically active substances which could negatively affect ecosystems., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Although the plastid genome is highly conserved across most angiosperms, multiple lineages have increased rates of structural rearrangement and nucleotide substitution. These lineages exhibit an excess of nonsynonymous substitutions (i.e., elevated dN/dS ratios) in similar subsets of plastid genes, suggesting that similar mechanisms may be leading to relaxed and/or positive selection on these genes. However, little is known regarding whether these mechanisms continue to shape sequence diversity at the intraspecific level., Results: We examined patterns of interspecific divergence and intraspecific polymorphism in the plastid genome of Campanulastrum americanum, and across plastid genes found a significant correlation between dN/dS and pN/pS (i.e., the within-species equivalent of dN/dS). A number of genes including ycf1, ycf2, clpP, and ribosomal protein genes exhibited high dN/dS ratios. McDonald-Kreitman tests detected little evidence for positive selection acting on these genes, likely due to the presence of substantial intraspecific divergence., Conclusions: These results suggest that mechanisms leading to increased nucleotide substitution rates in the plastid genome are continuing to act at the intraspecific level. Accelerated plastid genome evolution may increase the likelihood of intraspecific cytonuclear genetic incompatibilities, and thereby contribute to the early stages of the speciation process.

Previous studies based on DNA restriction-site and sequence variation have shown that the Hawaiian lobeliads are monophyletic and that the two largest genera, Cyanea and Clermontia, diverged from each other ca. 9.7 Mya. Sequence divergence among species of Clermontia is quite limited, however, and extensive hybridization is suspected, which has interfered with production of a well-resolved molecular phylogeny for the genus. Clermontia is of considerable interest because several species posses petal-like sepals, raising the question of whether such a homeotic mutation has arisen once or several times. In addition, morphological and molecular studies have implied different patterns of inter-island dispersal within the genus. Here we use nuclear ISSRs (inter-simple sequence repeat polymorphisms) and five plastid non-coding sequences to derive biparental and maternal phylogenies for Clermontia. Our findings imply that (1) Clermontia is not monophyletic, with Cl. pyrularia nested within Cyanea and apparently an intergeneric hybrid; (2) the earliest divergent clades within Clermontia are native to Kauài, then Òahu, then Maui, supporting the progression rule of dispersal down the chain toward progressively younger islands, although that rule is violated in later-evolving taxa in the ISSR tree; (3) almost no sequence divergence among several Clermontia species in 4.5 kb of rapidly evolving plastid DNA; (4) several apparent cases of hybridization/introgression or incomplete lineage sorting (i.e., Cl. oblongifolia, peleana, persicifolia, pyrularia, samuelii, tuberculata), based on extensive conflict between the ISSR and plastid phylogenies; and (5) two origins and two losses of petaloid sepals, or--perhaps more plausibly--a single origin and two losses of this homeotic mutation, with its introgression into Cl. persicifolia. Our phylogenies are better resolved and geographically more informative than others based on ITS and 5S-NTS sequences and nuclear SNPs, but agree with them in supporting Clermontia's origin on Kauài or some older island and dispersal down the chain subsequently.

The paper reported the chromosome number, karyotype and chromosome volume of Echinocodon lobophyllus. The normal diploid was 2n = 16, karyotype formula based on Levan's publication was K(2n) = 16= 14m + 2Sm. According to the method of S. R. Kuo, the chromosome relative length was 2n = 16 = 10M2 + 6M1, which belong to "1A" type according to the Stebbins' karyotype classification. The AS.K% was 57.24% from Arano's method. The total volume of chromosome groups was 1.16 microm3.