The chloroplast (cp) is an organelle with its own genome encoding a number of cp-specific components. The membrane-bound organelles are mainly involved in the photosynthetic conversion of atmospheric CO2 into carbohydrates in which light energy is stored as chemical energy. Resequencing technology via next-generation sequencing has recently been successfully applied which results the field of cp genome characterization is growing fast. Here, we report the complete sequence of the chloroplast genome of Capsicum frutescens, a species of chili pepper. The total length of the genome is 156,817 bp, and the overall GC content is 37.7%. A pair of 51,584-bp inverted repeats (IRs) is separated by a small (17,853 bp) and a large (87,380 bp) single-copy region. The C. frutescens chloroplast genome encodes 103 unique genes, including 79 protein-coding genes, 20 tRNA genes, and four rRNA genes. Of these, 19 genes are duplicated in the IRs and 18 genes contain one or two introns. Comparative analysis with reference cp genome revealed 125 simple sequence repeat (SSR) motif and 34 variants, mostly located in the non-coding regions. These microsatellite markers will facilitate the studies of genetic diversity, population genetic structure, and sustainable conservation for C. frutescens.

Chloroplast (cp) genome sequences provide a valuable source for DNA barcoding. Molecular phylogenetic studies have concentrated on DNA sequencing of conserved gene loci. However, this approach is time consuming and more difficult to implement when gene organization differs among species. Here we report the complete re-sequencing of the cp genome of Capsicum pepper (Capsicum annuum var. glabriusculum) using the Illumina platform. The total length of the cp genome is 156,817 bp with a 37.7% overall GC content. A pair of inverted repeats (IRs) of 50,284 bp were separated by a small single copy (SSC; 18,948 bp) and a large single copy (LSC; 87,446 bp). The number of cp genes in C. annuum var. glabriusculum is the same as that in other Capsicum species. Variations in the lengths of LSC, SSC and IR regions were the main contributors to the size variation in the cp genome of this species. A total of 125 simple sequence repeat (SSR) and 48 insertions or deletions variants were found by sequence alignment of Capsicum cp genome. These findings provide a foundation for further investigation of cp genome evolution in Capsicum and other higher plants.

Chloroplast DNA sequences are a versatile tool for species identification and phylogenetic reconstruction of land plants. Different chloroplast loci have been utilized for phylogenetic classification of plant species. However, there is no evidence for a short sequence that can distinguish all plant species from each other. Molecular markers derived from the complete chloroplast genome can provide effective tools for species identification and phylogenetic resolution. Thus, the complete chloroplast genome sequence of Korean landrace “Subicho” pepper (Capsicum annuum var. annuum) has been determined here. The total length of the chloroplast genome is 156,878 bp, with 37.7% overall GC content. A pair of IRs (inverted repeats) of 25,801 bp was separated by a small single copy (SSC) region of 17,929 bp and a large single copy (LSC) region of 87,347 bp. The chloroplast genome harbors 132 known genes, including 87 protein-coding genes, 8 ribosomal RNA genes, and 37 tRNA genes. A total of seven of these genes are duplicated in the inverted repeat regions, nine genes and six tRNA genes contain one intron, while two genes and a ycf have two introns. Analysis revealed 144 simple sequence repeat (SSR) loci and 96 variants, mostly located in the non-coding regions. The types and abundances of repeat units in Capsicum species were relatively conserved and these loci will be useful for developing molecular markers.

The chloroplast (cp) is an organelle with its own genome that encodes a number of cp-specific components. Resequencing technology via next-generation sequencing has recently been successfully applied to cp genome characterization. The field of cp characterization is rapidly growing due to its wide versatility and two complete chloroplast (cp) genome sequences of Capsicum species have been reported. We herein report the complete chloroplast genome sequence of Capsicum baccatum var. baccatum, a wild Capsicum species. The total length of the chloroplast genome is 157,145 bp with 37.7% overall GC content. One pair of inverted repeats, 25,910 bp in length, was separated by a small single-copy region (17,974 bp) and large single-copy region (87,351 bp). This region contains 86 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Eleven genes contain one or two introns. Pair-wise alignments of cp genome were performed for genome-wide comparison. Analysis revealed a total of 134 simple sequence repeat (SSR) motif and 282 insertions or deletions variants in the C. baccatum var. baccatum cp genome.

In order to assess the genetic diversity, phylogenetic relationships and population structure of Korean rice landraces, 76 accessions were estimated using agronomical traits and SSR markers. Among 11 agronomical traits, amylose content (AC) was the trait with the largest variance with values ranged from 4.9 to 28.39 %, while grain length (GL) was the lowest variance ranged from 4.4 to 5.9 cm. In the result of PCA, the first PC with Eigen value of 217.5 explained 60.3% of the total variance. Culm length (CL) was the variable with the largest positive loadings. Growth period (GP) was the positive variances, while AC was the negative variance. The second PC with Eigen value of 80.6 explained an additional 22.4% of the total variance. Growth period (GP) was variable with highest positive loading. Amylose content (AC) was variable with high positive, while CL was the negative variance. The 49 SSR markers produced a total of 473 alleles with an average of 9.6 alleles. The polymorphism information content (PIC) was in the range 0.11 to 0.93. The observed heterozygosity ranged from 0.12 to 0.39, with an average of 0.61. 76 rice accessions showed two subpoplations and three groups based on SSR markers. Group I and Gropu II appertained Pop-2 and Pop-1 subpopulation, respectively. They showed similar agronomical traits. Group III consisted 7 rice accessions predominantly appertained to Pop-1. These results provide insight into the characters of Korean rice landraces and help to improve our knowledge of rice breeding

DNA barcoding is the use of short DNA sequences of the genome for large scale species identification. The Consortium for the Barcode of Life (CBOL) plant-working group recommended the 2-locus combination as the standard plant barcode. The evolutions of the chloroplast regions combine with nuclear gens are sufficiently rapid to allow discrimination between closely related species. We evaluated the efficacy of the proposed plant barcoding loci matK along with ITS2 for barcoding Vigna species. To assess the discrimination ability of barcoding loci to resolve Vigna species, we sampled 52 of the taxonomically best known groups in the genus. Topologies of the phylogenetic trees based on ITS2 and matK analyses were similar but a few accessions were placed into distant phylogenetic groups. Neither ITS2 nor matK analyses were able to discriminate some closely related Vigna species alone. Thus, we used concatenated data to increase the resolving power of ITS2 and used matK as an additional tool for phylogenetic analysis in Vigna because characterization of the nucleotide sequences of matK region was easier to recover and more cost-effective than those of the ITS region.

Sesame (Sesamum indicum L.) is one of the most important oilseed crops with high oil contents and rich nutrient value. The development of a core collection could facilitate easier access to sesame genetic resources for their use in crop improvement programs and simplify the genebank management. The present study was initiated to the development and evaluation of a core collection of sesame based on 5 qualitative and 10 quantitative trait descriptors on 2,751 sesame accessions. The accessions were different countries of origin. About 10.1 percent of accessions were selected by using the power core program to constitute a core collection consisting of 278 accessions. Mean comparisons using t-test, Nei’s diversity index of 10 morphological descriptors and correlation coefficients among traits indicated that the existing genetic variation for these traits in the entire collection has been preserved in the core collection. The results from this study will provide effective information for future germplasm conservation and improvement programs in sesame.