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The camellia flower is a famous woody plant with a long-cultivated history and high ornamental value. It is extensively planted and utilized around the world and owns a massive germplasm resource. Camellia 'Xiari Qixin' belongs to one of the typical cultivars in the four seasons camellia hybrids series. Due to its long flowering period, this kind of cultivar is identified as a precious resource of camellia flowers. In this study, the complete chloroplast genome sequence of C. 'Xiari Qixin' was first reported. Its whole chloroplast genome is 157,039 bp in length with an overall GC content of 37.30%, composed of a large single copy region (LSC, 86,674 bp), a small single copy region (SSC, 18,281 bp), and a pair of inverted repeat regions (IRs, 26,042 bp each). A total of 134 genes were predicted in this genome, including 8 ribosomal RNA genes, 37 transfer RNA genes, and 89 protein-coding genes. In addition, 50 simple sequence repeats (SSRs) and 36 long repeat sequences were detected. By comparing C. 'Xiari Qixin' and seven Camellia species on the chloroplast genome, seven mutation hotspot regions were identified, including psbK, trnS (GCU)-trnG(GCC), trnG(GCC), petN-psbM, trnF(GAA)-ndhJ, trnP(UGG)-psaJ, and ycf1. Phylogenetic analysis of 30 chloroplast genomes showed that the genetic relationship between C. 'Xiari Qixin' and Camellia azalea is quite close in evolution. These results could not only provide a valuable database for determining the maternal origin of Camellia cultivars, but also contribute to the exploration of the phylogenetic relationship and utilization of germplasm resources for Camellia. [ABSTRACT FROM AUTHOR]

Abundant research has been conducted on the physiological, biochemical, and anatomical aspects of bamboo culm wall thickening, but its molecular mechanism has not yet been investigated. In this study, we performed whole-genome resequencing of Phyllostachys edulis 'Pachyloen', Phyllostachys nidularia f. farcta, Phyllostachys heteroclada f. solida with significantly thicker culm walls, and Schizostachyum dumetorum var. xinwuense with extremely thin culm walls. Moreover, we pioneered the innovative use of gene set subtraction to explore candidate genes that regulate bamboo culm wall thickening. A candidate gene set, containing 633 genes, was obtained by eliminating shared genes that help maintain physiological processes after alignment with the P. edulis reference genome. Starch and sucrose, oxidative phosphorylation, and ribosome were the three most important pathways enriched by differentially expressed genes. Although it cannot be used for hyperfine localization of bamboo wall thickness-regulatory genes, gene set reduction narrows down the range of candidate genes at minimal cost and provides new clues for the application of bioinformatics in plant research. [ABSTRACT FROM AUTHOR]