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To examine if the cultivation process has reduced the genetic variation of modern cultivars of the traditional Chinese medicinal plant, Coptis chinensis, the levels and distribution of genetic variation was investigated using ISSR markers. A total of 214 C. chinensis individuals from seven wild and three cultivated populations were included in the study. Seven ISSR primers were used and a total of 91 DNA fragments were scored. The levels of genetic diversity in cultivated populations were similar as those in wild populations (mean PPL = 65.2% versus PPL = 52.4%, mean H = 0.159 versus H = 0.153 and mean I = 0.255 versus I = 0.237), suggesting that cultivation did not seriously influence genetic variation of present-day cultivated populations. Neighbour-joining cluster analysis showed that wild populations and cultivated populations were not separated into two groups. The coefficient of genetic differentiation between a cultivar and its wild progenitor was 0.066 (G(st)), which was in good accordance with the result by amova analysis (10.9% of total genetic variation resided on the two groups), indicating that cultivated populations were not genetically differentiated from wild progenitors. For the seven wild populations, a significant genetic differentiation among populations was found using amova analysis (45.9% of total genetic variation resided among populations). A number of causes, including genetic drift and inbreeding in the small and isolated wild populations, the relative limited gene flow between wild populations (N(m) = 0.590), and high gene flow between cultivars and their wild progenitors (N(m) = 7.116), might have led to the observed genetic profiles of C. chinensis.

LEAFY (LFY) is a plant-specific transcription factor, which is found in algae and all land plants. LFY homologs exert ancestral roles in regulating cell division and obtain novel functions to control floral identity. Isoetes L. is an ancient genus of heterosporous lycophytes. However, characters about LFY homologs in lycophytes remain poorly investigated. In this study, two LFY homologs, ILFY1 and ILFY2, were cloned from five Isoetes species, including I. hypsophila, I. yunguiensis, I. sinensis, I. orientalis, and I. taiwanensis. The full length of ILFY1 was 1449–1456 bp with an open reading frame (ORF) of 927–936 bp. The full length of ILFY2 was 1768 bp with ORF of 726 bp. Phylogenetic tree revealed that ILFY1 and ILFY2 were separated into two clades, and I. hypsophila were separated with the others. Expression analysis demonstrated that IsLFY1 and IsLFY2 for I. sinensis did not show functional diversity. The two transcripts were similarly accumulated in both vegetative and reproductive tissues and highly expressed in juvenile tissues. In addition, the IsLFY1 and IsLFY2 transgenic Arabidopsis similarly did not promote precocious flowering, and they were inactive to rescue lfy mutants. The results facilitate general understandings about the characteristics of LFY in Isoetes and evolutionary process.

Plant peptides play important roles in various aspects of plant growth and development. The RTFL/DVL family includes small peptides that are widely conserved among land plants. Overexpression of six RTFL genes in Arabidopsis was suggestive of their functions as negative regulators of cell proliferation and as positional cues along the longitudinal axis of the plant body . At this time, few reports are available on RTFL paralogs in other species and the evolutionary relationship of RTFL members among land plants remains unclear. In this study, we compared and analyzed whole amino acid sequences of 188 RTFL members from 22 species among land plants and identified 73 motifs. All RTFL members could be grouped into four clades, and each clade exhibited specific motif patterns, indicative of unique evolutionary traits in the RTFL family. In agreement with this hypothesis, we analyzed two RTFL members from Oryza sativa and Arabidopsis by overexpressing them in Arabidopsis, revealing similar phenotypes suggestive of a conserved function of the RTFL family between eudicots and monocots, as well as different phenotypes and unique functions.Electronic supplementary materialThe online version of this article (doi:10.1007/s10265-015-0703-1) contains supplementary material, which is available to authorized users.

Many plant species exhibit different leaf morphologies within a single plant, or heterophylly. The molecular mechanisms regulating this phenomenon, however, have remained elusive. In this study, the transcriptomes of submerged and floating leaves of an aquatic heterophyllous plant, Potamogeton octandrus Poir, at different stages of development, were sequenced using high-throughput sequencing (RNA-Seq), in order to aid gene discovery and functional studies of genes involved in heterophylly. A total of 81,103 unigenes were identified in submerged and floating leaves and 6,822 differentially expressed genes (DEGs) were identified by comparing samples at differing time points of development. KEGG pathway enrichment analysis categorized these unigenes into 128 pathways. A total of 24,025 differentially expressed genes were involved in carbon metabolic pathways, biosynthesis of amino acids, ribosomal processes, and plant-pathogen interactions. In particular, KEGG pathway enrichment analysis categorized a total of 70 DEGs into plant hormone signal transduction pathways. The high-throughput transcriptomic results presented here highlight the potential for understanding the molecular mechanisms underlying heterophylly, which is still poorly understood. Further, these data provide a framework to better understand heterophyllous leaf development in P. octandrus via targeted studies utilizing gene cloning and functional analyses.