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Carex agglomerata C. B. Clarke is a sedge with excellent ornamental characters, it is an important ecosystem stabilizer. Here we report the complete chloroplast genome of C. agglomerata to provide a foundation for further phylogenetic studies on the Cyperaceae. The chloroplast (cp) genome is 184,157 bp in size and consists of a large single-copy (LSC) region 106,654 bp in length, a small single-copy (SSC) region of 36,099 bp, two inverted repeats (IR) regions each 20,702 bp. The total GC content of the cp genome is 33.9% with the LSC, SSC, and IR regions 32, 32.5, and 42.9%, respectively. The cp genome contains 128 genes, including 80 protein-coding, 40 tRNA, and eight rRNA genes. The phylogenetic analysis showed C. agglomerata is in a clade with Carex neurocarpa Maxim and Carex siderosticta Hance. This study provides a basis for further phylogenetic studies of Carex.

The complete chloroplast genome of Fargesia qinlingensis (Poaceae) has been reconstructed from the whole-genome Illumina sequencing data. The complete chloroplast genome sequence of F. qinlingensis obtained in this study was 139,640 bp in length, with a large single copy (LSC) region of 83,220 bp, a small single copy (SSC) region of 12,826 bp, separated by two inverted repeat (IR) regions of 21,797 bp each. The GC content was 38.9%, and in the LSC, SSC, and IR regions were 37.0%, 33.2%, and 44.2%, respectively. A total of 130 genes were annotated, including 83 protein-coding genes (PCGs), 39 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The result of the phylogenetic analysis showed that F. qinlingensis was more closely related to the species of F. denudata.

Xiphidiopsis (Xiphidiopsis) gurneyi belongs to Meconematinae. The complete mitochondrial genome of X. (X.) gurneyi was sequenced by the next-generation sequencing (NGS) technology. The total length of the mitogenome was 16,225 bp and contains the typical gene arrangement, base composition, codon usage found in Meconematinae species. Phylogenetic tree was constructed based on concatenated datasets of PCGs and rRNAs of X. (X.) gurneyi and 19 Tettigoniidae species to assess their phylogenic relationship. Phylogenetic analysis showed that X. (X.) gurneyi was more closely related to the genus of Xizicus.

The length of Alloxiphidiopsis emarginata complete mitogenome was 16,207 bp and contained the typical gene arrangement, base composition, codon usage found in other related species. The overall base composition exhibited obvious anti-G (10.6%) and AT bias (71.6%). The initiation codons of all PCGs were typical ATN (ATA/ATG/ATT), and the termination codons were TAA, TAG, or incomplete stop codon T. All tRNAs could be folded into typical cloverleaf secondary structures, except tRNASer (AGN). Phylogenetic analyses showed that A. emarginata was closer with Xizicus howardi.

Some species of Allium in Liliaceae have fistular leaves. The fistular lamina of Allium fistulosum undergoes a process from solid to hollow during development. The aims were to reveal the process of fistular leaf formation involved in programmed cell death (PCD) and to compare the cytological events in the execution of cell death to those in the unusual leaf perforations or plant aerenchyma formation. In this study, light and transmission electron microscopy were used to characterize the development of fistular leaves and cytological events. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays and gel electrophoresis were used to determine nuclear DNA cleavage during the PCD. The cavity arises in the leaf blade by degradation of specialized cells, the designated pre-cavity cells, in the center of the leaves. Nuclei of cells within the pre-cavity site become TUNEL-positive, indicating that DNA cleavage is an early event. Gel electrophoresis revealed that DNA internucleosomal cleavage occurred resulting in a characteristic DNA ladder. Ultrastructural analysis of cells at the different stages showed disrupted vacuoles, misshapen nuclei with condensed chromatin, degraded cytoplasm and organelles and emergence of secondary vacuoles. The cell walls degraded last, and residue of degraded cell walls aggregated together. These results revealed that PCD plays a critical role in the development of A. fistulosum fistular leaves. The continuous cavity in A. fistulosum leaves resemble the aerenchyma in the pith of some gramineous plants to improve gas exchange.

The formation of secretory cavities in Rutaceae has been the subject of great interest. In this study, cytological events that are involved in the lysigenous formation of the secretory cavities in the leaves of Dictamnus dasycarpus are characterized by an interesting pattern of programmed cell death (PCD). During the developmental process, clusters of cells from a single protoepidermal cell embark on different trajectories and undergo different cell death fates: the cell walls of the secretory cells have characteristics of thinning or complete breakdown, while the sheath cells present a predominantly thick-walled feature. A DAPI assay shows deformed nuclei that are further confirmed to be TUNEL-positive. Gel electrophoresis indicates that DNA cleavage is random and does not result in ladder-like DNA fragmentation. Ultrastructurally, several remarkable features of PCD have been determined, such as misshapen nuclei with condensed chromatin and a significantly diffused membrane, degenerated mitochondria and plastids with disturbed membrane systems, multivesicular bodies, plastolysomes, vacuole disruption and lysis of the center secretory cell. Cytological evidence and Nile red stains exhibit abundant essential oils accumulated in degenerated outer secretory cells after the dissolution of the center secretory cell. In addition, explanations of taxonomic importance and the relationship between PCD and oil droplet accumulation in the secretory cavities are also discussed.

Chloroplast (cp) genome sequences became a widely used tool for evolutionary and phylogenetic studies in plants. Abies chensiensis (Pinaceae: Abietoideae) is an endangered species endemic to China. To understand its evolutionary characteristics, the complete chloroplast genome of the A. chensiensis has been reconstructed from the whole-genome Illumina sequencing data. The circular genome is 121,784 bp in length and without a typical quadripartite structure due to the loss of IR region. The total GC content of whole genome sequence is 38.3%. The chloroplast genome encodes 109 genes, including 75 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Among them, 35 genes involved in photosynthesis, while 58 genes involved in self-replication. The Maximum-Likelihood phylogenetic analysis showed a strong sister relationship with A. nephrolepis and A. koreana in Abietoideae. Our findings provide fundamental information for further evolutionary and phylogenetic researches of Abietoideae.