Simple sequence repeats (SSRs) or microsatellite markers derived from expressed sequence tags (ESTs) are routinely used for molecular assisted-selection breeding, comparative genomic analysis, and genetic diversity studies. In this study, we investigated 54,546 ESTs for the identification and development of SSR markers in Pogostemon cablin (Patchouli). In total, 1219 SSRs were identified from 1144 SSR-containing ESTs. Trinucleotides (80.8%) were the most abundant SSRs, followed by di- (10.8%), mono- (7.1%), and hexa-nucleotides (1.3%). The top six motifs were CCG/CGG (15.3%), AAG/CTT (15.0%), ACC/GGT (13.5%), AGG/CCT (12.4%), ATC/ATG (9.9%), and AG/CT (9.8%). On the basis of these SSR-containing ESTs, a total of 192 primer pairs were randomly designed and used for polymorphism analysis in 38 accessions collected from different geographical regions of Guangdong, China. Of the SSR markers, 45 were polymorphic and had allele variations from two to four. Furthermore, a transferability analysis of these primer pairs revealed a 10–40% cross-species transferability in 10 related species. This report is the first comprehensive study on the development and analysis of a large set of SSR markers in P. cablin. These markers have the potential to be used in quantitative trait loci mapping, genetic diversity studies, and the fingerprinting of cultivars of P. cablin.

Background: Angelica dahuricabelongs to the Apiaceae family, whose dry root is a famous traditional Chinese medicine named as “Bai zhi”. There are two cultivars (A. dahuricacv. ‘Hangbaizhi’ andA. dahuricacv. ‘Qibaizhi’), which have been domesticated for thousands of years. Long term artificial selection has led to great changes in root phenotypes of the two cultivars, and also decreased their adaptability to environment. We proposed hypothesis that the cultivars may have lost some of the genetic diversity found in the wild species and may be highly differentiated from the latter during the domestication process. However, few studies have been carried out on how domestication affected the genetic variation of this species. Here, we accessed the levels of genetic variation and differentiation within and between wildA. dahuricapopulations and two cultivars using 12 microsatellite markers.Results: The results revealed that the genetic diversity of the cultivars was much lower than that of wildA. dahurica, andA. dahuricacv. ‘Qibaizhi’ had lower genetic diversity compared toA. dahuricacv. ‘Hangbaizhi’. AMOVA analysis showed significant genetic differentiation between the wild and cultivatedA. dahuricapopulations, and betweenA. dahuricacv. ‘Hangbaizhi’ andA. dahuricacv. ‘Qibaizhi’. Results from Bayesian, UPGMA, NJ and PcoA clustering analysis indicated that all 15 populations were assigned to two genetic clusters corresponding to the wild and cultivated populations. Bayesian clustering analysis further divided the cultivated populations into two sub-clusters corresponding to the two cultivars.Conclusions: Our study suggests that the domestication process is likely the major factor resulting in the loss of genetic diversity in cultivatedA. dahuricapopulations and in significant genetic differentiation from the wild populations due to founder effect and/or artificially directional selections. This large-scale analysis of population genetics could provide valuable information for genetic resources conservation and breeding programs ofAngelica dahurica.

Background: Wuzhimaotao (Radix Fici Hirtae) originates from the dry root ofFicushirta(Moraceae), which is widely known as a medical and edible plant distributed in South China. As the increasing demand for Wuzhimaotao, the wildF.hirtahas been extremely reduced during the past years. It is urgent to protect and rationally develop the wild resources ofF.hirtafor its sustainable utilization. However, a lack of genetic background ofF.hirtamakes it difficult to plan conservation and breeding strategies for this medical plant. In the present study, a total of 414 accessions ofF.hirtafrom 7 provinces in southern China were evaluated for the population genetics using 9 polymorphic SSR markers.Results: A mean of 17.1 alleles per locus was observed. The expected heterozygosity (He) varied from 0.142 to 0.861 (mean = 0.706) in nine SSR loci. High genetic diversity (H_e = 0.706, ranged from 0.613 to 0.755) and low genetic differentiation among populations (G’_ST = 0.147) were revealed at population level. In addition, analysis of molecular variance (AMOVA) indicated that the principal molecular variance existed within populations (96.2%) was significantly higher than that among populations (3.8%). Meanwhile, the three kinds of clustering methods analysis (STRUCTURE, PCoA and UPGMA) suggested that the sampled populations were clustered into two main genetic groups (K = 2). Mantel test showed a significant correlation between geographic and genetic distance among populations (R² = 0.281,P < 0.001). Pollen flow, seed flow and/or geographical barriers might be the main factors that formed the current genetic patterns ofF.hirtapopulations.Conclusions: This is a comprehensive study of genetic diversity and population structure ofF.hirtain southern China. We revealed the high genetic diversity and low population differentiation in this medicinal plant and clarified the causes of its current genetic patterns. Our study will provide novel insights into the exploitation and conservation strategies forF.hirta.

Background: Angelica dahurica (Apiaceae) is an important herb in traditional Chinese medicine. Because of its important medicinal and economic values, its wild resources were over-exploited and increasingly reduced. Meanwhile, the diversity of cultivars of A. dahurica has decreased as a result of long-term artificial cultivation. However, there are no population genetics studies of natural A. dahurica reported yet, especially for using microsatellite markers (SSRs) to investigate population genetics of the species. Results: Sixteen polymorphic EST-SSR loci were isolated from A. dahurica with transcriptome sequencing technology (RNA-Seq). The number of alleles varied from 2 to 15 per polymorphic locus over populations with the observed and expected heterozygosities ranging from 0.000 to 1.000 and from 0.000 to 0.829, respectively. Significant deviations from Hardy–Weinberg equilibrium were observed at 8 loci. Tests of linkage disequilibrium showed 11 informative locus pairs were significant across all populations. Cross-species amplification showed that 14 out of 16 SSR loci have the transferability in cultivar-A. dahurica cv. ‘Hangbaizhi’ and A. decursiva. Conclusions: The 16 newly developed loci microsatellite primers with RNA-Seq will be useful for further investigating population genetics of A. dahurica, cultivars and other members of this genus.

Background: Wuzhimaotao (the dry root of Ficus hirta) is used as both medicine and food ingredient by the locals in areas around Nanling Mountains of China. Due to its very similar external morphologies with Duanchangcao (the root of Gelsemium elegans, which contains gelsemine that is extremely neurotoxic) and the associated growth of these two plants, incidents of food poisoning and even death frequently occur, resulting from the misuse of Duanchangcao as Wuzhimaotao. The aim of this study is to develop a fast, even, on-spot approach to identification of Wuzhimaotao. Methods: We used DNA barcode-based recombinase polymerase amplification (BAR-RPA) with species–specific primers targeting the internal transcribed spacer (ITS) region of the rDNA of F. hirta. BAR-RPA reaction time and temperature were optimized and the specificity and sensitivity of BAR-RPA species–specific primers were assessed. Results: This technique showed a high specificity and sensitivity to amplify the genomic DNA of F. hirta and allowed for rapid amplification (within 15 min) of the ITS region under a constant and mild temperature range of 37–42 °C without using thermocyclers. Conclusions: The BAR-RPA assay with a fast DNA extraction protocol provides a simple, energy-saving, and rapid method for identification of Wuzhimaotao in both laboratory and field settings.

While the communities constituted by phytophageous insects and their parasites may represent half of all terrestrial animal species, understanding their diversification remains a major challenge. A neglected idea is that geographic phenotypic variation in a host plant may lead to heterogeneous evolutionary responses of the different members of the associated communities. This could result in diversification on a host plant by ecological speciation in some species, leading to geographic variation in community composition. In this study we investigated geographic variation of inflorescence receptacle size in a plant, Ficus hirta, and how the hymenopteran community feeding in the inflorescences has responded. Our predictions were: 1) Inflorescence size variation affects wasp species differently depending on how they access oviposition sites. 2) In some affected lineages of wasps, we may observe vicariant, parapatric species adapted to different inflorescence sizes. Inflorescence size variation affects wasp species differently depending on how they access oviposition sites. In some affected lineages of wasps, we may observe vicariant, parapatric species adapted to different inflorescence sizes. We show that fig (the enclosed inflorescence of Ficus) wall thickness varies geographically. The fig-entering pollinating wasp was not affected, while the parasites ovipositing through the fig wall were. Two parapatric species of Philotrypesis, exhibiting strikingly different ovipositor lengths, were recorded. One species of Sycoscapter was also present, and it was restricted, like the shorter-ovipositor Philotrypesis, to the geographic zone where fig walls were thinner. Previous work on fig wasps suggested that parapatric geographic ranges among congenerics were due to adaptation to variation in abiotic factors, complemented by interspecific competition. Our results show that parapatric ranges may also result from adaptation to variation in biotic factors. Within an insect community, differences among species in their response to geographic phenotypic variation of their host plant may result in geographically heterogeneous community structure. Such heterogeneity leads to heterogeneous interaction networks among sites. Our results support the hypothesis that plant geographic phenotypic variation can be a driver of diversification in associated insect communities, and can complement other diversification processes.