In this study, we report the plastome of Eriocaulon decemflorum (Eriocaulaceae) and make an effort to understand the genome evolution, structural rearrangements and gene content of the order Poales by comparing it with other available plastomes. The size of complete E. decemflorum plastome is 151,671 bp with an LSC (81,477bp), SSC (17,180bp) and a pair of IRs (26,507 bp). The plastome exhibits GC content of 35.8% and 134 protein-coding genes with 19 genes duplicated in the IR region. The Eriocaulaceae plastome is characterized by the presence of accD, ycf1 and ycf2 genes and presence of introns in clpP and rpoC1 genes which have been lost in the Graminid plastomes. Phylogenomic analysis based on 81 protein-coding genes placed Eriocaulaceae sister to Mayacaceae. The present study enhances our understanding of the evolution of Poales by analyzing the plastome data from the order.
11 March 2015 in Genetic Resources and Crop Evolution
The genus Limonium, commonly known as Sea Lavenders, is one of the most species-rich genera of the family Plumbaginaceae. In this study, two new plastomes for the genus Limonium, viz. L. tetragonum and L. bicolor, were sequenced and compared to available Limonium plastomes, viz. L. aureum and L. tenellum, to understand the gene content and structural variations within the family. The loss of the rpl16 intron and pseudogenisation of rpl23 was observed. This study reports, for the first time, expansion of the IRs to include the ycf1 gene in Limonium plastomes, incongruent with previous studies. Two positively selected genes, viz. ndhF and ycf2, were identified. Furthermore, putative barcodes are proposed for the genus, based on the nucleotide diversity of four Limonium plastomes.
Capparis gialaiensis Sy, a new species of Capparaceae from Vietnam is described and illustrated. It is morphologically closest to C. longistipitata, but differs in length of thorns, filaments and gynophore, shape of the leaf and shape and size of petals. Color photographs, a table comparing the new species with closely allied species and a key are provided to facilitate species identification.
Eriocaulon parvicephalum, a new species of Eriocaulaceae from Western Ghats of India, is described and illustrated. The new species is closely allied with E. palghatense but differs in having acuminate spathe lobes, eglandular petals in the male flower, and two rectangular seed coat appendages per cell. Phylogenetic analyses using the ITS region of nuclear ribosomal DNA, and psbA–trnH and trnL–F intergenic spacer regions of chloroplast DNA support the status of E. parvicephalum as a new species.