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The internal transcribed spacer (ITS) region was employed to analyze phylogeny of 20 populations, including the local cultivar “Nanjiang”, belonging to 7 species of Lonicera L. 20 ITS sequences that we obtained range from 614 to 618 bp, and the G+C content was higher than 60% with the average value 63.5%. The sequences of 5.8S nrDNA was highly conservative in both length and component, while ITS2 had more variation than ITS1 in sequence component and length. For the ITS complete sequence, the mutation and information sites were 139 and 117 with the content of 22.38 and 18.84%, respectively. The dendrogram analysed by neighbor-joining method showed that “Nanjiang” and Lonicera similis Hemsl. comprised a same cluster with a higher bootstrap support, indicating “Nanjiang” would be a variation or subspecies of L. similis Hemsl. The results of antibacterial activity test and active compounds identification showed that “Nanjiang” had the best antibacterial activity and the highest yield of chlorogenic acid, the active component of Flos Lonicerae, in the six species of Lonicera L.

BACKGROUND: The safflower, Carthamus tinctorius L., is a worldwide oil crop, and its flowers, which have a high flavonoid content, are an important medicinal resource against cardiovascular disease in traditional medicine. Because the safflower has a large and complex genome, the development of its genomic resources has been delayed. Second-generation Illumina sequencing is now an efficient route for generating an enormous volume of sequences that can represent a large number of genes and their expression levels. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the genes and pathways that might control flavonoids and other secondary metabolites in the safflower, we used Illumina sequencing to perform a de novo assembly of the safflower tubular flower tissue transcriptome. We obtained a total of 4.69 Gb in clean nucleotides comprising 52,119,104 clean sequencing reads, 195,320 contigs, and 120,778 unigenes. Based on similarity searches with known proteins, we annotated 70,342 of the unigenes (about 58% of the identified unigenes) with cut-off E-values of 10(-5). In total, 21,943 of the safflower unigenes were found to have COG classifications, and BLAST2GO assigned 26,332 of the unigenes to 1,754 GO term annotations. In addition, we assigned 30,203 of the unigenes to 121 KEGG pathways. When we focused on genes identified as contributing to flavonoid biosynthesis and the biosynthesis of unsaturated fatty acids, which are important pathways that control flower and seed quality, respectively, we found that these genes were fairly well conserved in the safflower genome compared to those of other plants. CONCLUSIONS/SIGNIFICANCE: Our study provides abundant genomic data for Carthamus tinctorius L. and offers comprehensive sequence resources for studying the safflower. We believe that these transcriptome datasets will serve as an important public information platform to accelerate studies of the safflower genome, and may help us define the mechanisms of flower tissue-specific and secondary metabolism in this non-model plant.