Here, we report a completely sequenced plastome using Illumina/Solexa sequencing-by-synthesis (SBS) technology. The plastome of Magnolia kwangsiensis Figlar & Noot. is 159 667 bp in length with a typical quadripartite structure: 88 030 bp large single-copy (LSC) and 18 669 bp small single-copy (SSC) regions, separated by two 26 484 bp inverted repeat (IR) regions. The overall predicted gene number is 129, among which 17 genes are duplicated in IR regions. The plastome of M. kwangsiensis is identical in its gene order to previously published plastomes of magnoliids. Furthermore, the C-to-U type RNA editing frequency of 114 seed plants is positively correlated with plastome GC content and plastome length, whereas plastome length is not correlated with GC content. A total of 16 potential putative barcoding or low taxonomic level phylogenetic study markers in Magnoliaceae were detected by comparing the coding and noncoding regions of the plastome of M. kwangsiensis with that of Liriodendron tulipifera L. At least eight markers might be applied not only to Magnoliaceae but also to other taxa. The 86 mononucleotide cpSSRs that distributed in single-copy noncoding regions are highly valuable to study population genetics and conservation genetics of this endangered rare species.

Gentianales consist of Apocynaceae, Gelsemiaceae, Gentianaceae, Loganiaceae, and Rubiaceae, of which the majority are woody plants in tropical and subtropical areas. Despite extensive efforts in reconstructing the phylogeny of Gentianales based on molecular data, some interfamily and intrafamily relationships remain uncertain. We reconstructed the genus-level phylogeny of Gentianales based on the supermatrix of eight plastid markers (rbcL, matK, atpB, ndhF, rpl16, rps16, the trnL-trnF region, and atpB-rbcL spacer) and one mitochondrial gene (matR) using maximum likelihood. The major clades and their relationships retrieved in the present study concur with those of previous studies. All of the five families of Gentianales are monophyletic with strong support. We resolved Rubiaceae as sister to the remaining families in Gentianales and showed support for the sister relationship between Loganiaceae and Apocynaceae. Our results provide new insights into relationships among intrafamilial clades. For example, within Rubiaceae we found that Craterispermeae were sister to Morindeae þ (Palicoureeae þ Psychotrieae) and that Theligoneae were sister to Putorieae. Within Gentianaceae, our phylogeny revealed that Gentianeae were sister to Helieae and Potalieae, and subtribe Lisianthiinae were sister to Potaliinae and Faroinae. Within Loganiaceae, we found Neuburgia as sister to Spigelieae. Within Apocynaceae, our results supported Amsonieae as sister to Melodineae, and Hunterieae as sister to a clade comprising Plumerieae þ (Carisseae þ APSA). We also confirmed the monophyly of Perplocoideae and the relationships among Baisseeae þ (Secamonoideae þ Asclepiadoideae).

Litter participates in material circulation and energy transfer, and is an important part of carbon pool, which affects the ecological service function of soil and water conservation. In this paper, the natural forest of Pinus massoniana in Hengshan Mountain was taken as the research object. Through collecting the litter of the natural forest of Pinus massoniana, the composition of the litter and the annual litter amount of each component were analyzed. The results showed that: the litter was mainly composed of bark, cones, branches, needles, broad leaves and semi decomposition. The average annual litter amount of each component was 49.47 g/m2, 84.35 g/m2, 108.87 g/m2, 318.45 g/m2, 101.11 g/m2, 372.62 g/m2, respectively. The main components were semi decomposition, needles and branches. The annual total amount was 884.61–1207.68 g/m2, which increased with the forest age. To master the litter composition characteristics of Pinus massoniana natural forest is helpful for the further study of its decomposition characteristics and the measurement of water.