The history of Rehmannia glutinosa breeding has already beyond 100 years. There are rich cultivated varieties and wild germplasm resources in R. glutinosa. However, there also exist a lot of problems, such as, the pedigree of the existing varieties is not clear, the genetic basis is narrow, backward method of germplasm enhancement and breeding. Breeding of new varieties has been unable to meet the demand of R. glutinosa production in the new era. This paper summarizes the species of Rehmannia and their distribution, the diversity of plant morphology and the quality of R. glutinosa germplasm resources, as well as the progress of R. glutinosa breeding in recent 100 years. For ensuring the orderly, effective and safe production of R. glutinosa, the authors suggest to establish the wild resources protection area and germplasm resources garden, deeply study the genetic base of quality, strengthen application of new breeding method such as mutation breeding, haploid breeding and gene editing.
Plant Breeding ; Plants, Medicinal ; genetics ; Rehmannia ; genetics

Root rot was occurred widely in the production area of Rehmannia glutinosa, and which result in serious influence on the yield and quality of R. glutinosa. In the present work, a new phytopathogen was isolated from roots with root rot symptom in the production area of R. glutinosa. The colony of the pathogen growing on PDA medium was gray-black, the structure of hyphae was compact, the aerial hyphae was less developed, and the back of the colony was black. The hyphae of the pathogen were uneven in size, about 2 to 3 μm in diameter and twined with each other, the conidia of the pathogen were small, nearly round and about 1 μm in diameter. The healthy roots of R. glutinosa were inoculated with the pathogen in vitro, black-brown rot was observed at the inoculate sites after a few days' incubation. The rhizosphere soil of healthy R. glutinosa seedlings were inoculated in vivo, the leaves were wilted and the roots were black-brown rotted after several days' normal culture, the symptoms were consistent with those observed in the field. The genomic DNA of the pathogen was amplified by fungus rDNA-ITS universal primer ITS1/ITS4 and homologous analyzed, the pathogen was in a branch with Heterophoma sp., Phoma sp., P. novae-verbascicola and P. herbarum with the nuclear acid homology of 99.21% to 99.43%. The pathogen shown 97.00% to 98.02% nuclear acid homology with H. verbascicola, H. novae-verbascicola, H. poolensis, P. herbarum, H. sylvatica, H. verbascicola and H. verbasci-densiflori when amplified by the tub2 gene special primer Btub2 fd/Btub4 rd, and H. novae-verbascicola was the highest. The pathogen was in a branch with H. novae-verbascicola when amplified by the lsu gene special primer LR0 R/LR7. Based on the morphological characteristics, nucleotide sequence analysis and Koch's test results, the isolated pathogen causing root rot of R. glutinosa was identified as H. novae-verbascicola. This study is of great significance for the further theoretical research on root rot of R. glutinosa and root rot control in field.
DNA, Ribosomal ; Fungi/genetics* ; Plant Leaves ; Rehmannia/genetics* ; Seedlings

The present study analyzed the effects of planting density on the development, quality, and gene transcription characte-ristics of Rehmannia glutinosa using 85-5 and J9 as materials with three planting densities of 5 000, 25 000, and 50 000 plants/Mu(1 Mu≈667 m~2). The agronomic characteristics of leaves and tuberous roots, the content of catalpol and acteoside, and the changes of gene expression were determined. The results showed that the leaf size, the diameter of tuberous root, leaf biomass, tuberous root number, and tuberous root biomass per plant at low density were significantly higher than those of medium and high densities. The content of catalpol and acteoside in leaves was higher at high density. The content of catalpol in tuberous roots was higher at low density, and the change trend was similar to that in leaves, while the content of acteoside in tuberous roots was higher at high density. Transcriptome analysis found that about 1/2 of the expansin genes could change regularly in response to density treatment, which was rela-ted to the development of tuberous roots. The change trend of the gene expression of multiple catalytic enzymes involved in the biosynthesis of catalpol and acteoside was consistent with that of their content, which was presumedly involved in the accumulation and regulation of density-responsive medicinal components. Based on the analysis of the development, medicinal components, and gene expression characteristics of R. glutinosa at different densities, this study is expected to provide an important basis for regulating the quality and yield of medicinal materials of R. glutinosa by managing the planting density.
Gene Expression Profiling ; Plant Leaves/genetics* ; Plant Roots/genetics* ; Rehmannia/genetics* ; Transcription, Genetic

OBJECTIVETo analyze the genetic diversity of wild Rehmannia glutinosa and evaluate and compare random amplified polymorphic DNA (RAPD) and inter sample sequence repeat (ISSR) for analysis of R. glutinosa accessions.

METHODTwo molecular markers, RAPD and ISSR were used for analyzing 55 wild R. glutinosa accessions.

RESULTAverage 16.00 and 19.08 bands were amplified by RAPD primers and ISSR primers respectively, and the percentage of polymorphic bands were 89.58% and 94.32% respectively; Fifty-five R. glutinosa accessions categorized into 7 clusters were identified by unweighted pair-group method, arithmetic average (UPGMA) method.

CONCLUSIONA high level of genetic diversity of wild Rehmannia glutinosa was displayed at DNA level, and genetic diversity coefficient of R. glutinosa from different production areas was 0.63-0.98, and ISSR marker can detect higher genetic diversity of R. glutinosa germplasms than RAPD marker.

Genetic Variation ; genetics ; Phylogeny ; Random Amplified Polymorphic DNA Technique ; methods ; Rehmannia ; classification ; genetics

The study aims at evaluating genetic diversity and medicinal quality of cultivated germplasm in Rehmannia glutinosa, and providing theoretical guidance for screening excellent germplasm. The genetic diversity of 21 species of R. glutinosa were analyzed by SRAP molecular markers, and the catalpol and verbascoside was determined by HPLC. The mass fraction of catalpol and verbascoside in R. glutinosa germplasm were respectively in the range of 2.393%-6.519% and 0.063%-0.478%, the germplasm 14, 16, 15 and 20 germplasm, witch catalpol and verbascoside content was higher. A total of 57 bands were produced by 10 primer, among which 40 polymorphic bands were polymorphic bands, and the percentage of polymorphic loci was 8.77%-54.39%, the Nei's genetic diversity index (H) was 0.374 1, Shannon's polymorphism information index (I) was 0.546 6. Gst and gene flow Nm were 0.608 8 and 0.321 3, respectively. Based on the genetic uniformity, 21 species of germplasm were grouped into 2 categories. The genetic diversity level of R. glutinosa was medium low. The comprehensive consideration of the genetic diversity and the content inculde catalpol and verbascoside, germplasm 7 and germplasm 18 could be used as the preferred materials for the cultivation of reticulum. Germplasm 15 and 16 can be used as the preservation and breeding object of rhubarb germplasm.
Animals ; Gene Flow ; Genetic Variation ; Phylogeny ; Plant Breeding ; Plants, Medicinal ; genetics ; Rehmannia ; genetics

Iridoid synthase( IS),the key enzyme in the natural biosynthesis of vegetal iridoids,catalyzes the irreversible cyclization of 10-oxogeranial to epi-iridodial. In this study,we screened the Rehmannia glutinosa transcriptome data by BLASTn with Catharanthus roseus CrIS cDNA,and found four c DNA fragments with length of 1 527,1 743,1 425,1 718 bp,named RgIS1,RgIS2,RgIS3 and RgIS4,respectively. Bioinformatics analysis revealed that the four iridoid synthase genes encoding proteins with 389-392 amino acid residues,protein molecular weights were between 44. 30-44. 74 k Da,and theoretical isoelectric points were between 5. 30 and 5. 87. Subcellular localization predictions showed that the four iridoid synthase were distributed in the cytoplasm. Structure analysis revealed that R. glutinosa iridoid synthases contain six conserved short-chain dehydrogenase/reductase( SDR) motifs,and their 3 D models were composed typical dinucleotide-binding " Rossmann" folds covered by helical C-terminal extensions. Using the amino acid sequences of four R. glutinosa iridoid synthases,phylogenetic analysis was performed,the result indicated that RgIS3,CrIS and Olea europaea OeIS were grouped together,the other R. glutinosa iridoid synthases and fifteen proteins in other plants had close relationship. Real-time fluorescent quantitative PCR revealed that RgIS1 and RgIS3 highly expressed in unfold leaves,however,RgIS2 and RgIS4 highly expressed in stems and tuberous roots,respectively. RgIS3 showed higher expression levels in non-radial striations( nRS) of the two cultivars,and RgIS1 and RgIS2 had higher expression levels in nRS of QH,while RgIS4 had less expression levels in nRS of QH1. RgIS1,RgIS2 and RgIS3 were up-regulated by Me JA treatment,although the time and degree of response differed. Our findings are helpful to reveal molecular function of R. glutinosa iridoid synthases and provide a clue for studing the molecular mechanism of iridoid biosynthesis.
Cloning, Molecular ; Genes, Plant ; Iridoids ; metabolism ; Ligases ; genetics ; Phylogeny ; Rehmannia ; enzymology ; genetics

OBJECTIVETo provide molecular evidences for its breeding by studying the genetic relationship among varieties of Rehmannia glutinosa.

METHODNineteen varieties were detected by Randomly Amplified Polymorphic DNA(RAPD) markers.

RESULTThe 20 selected primers produced 163 bands, among which 114(69.9%) were polymorphic. A DNA molecular dendrogram was established based on Hierarchical cluster analysis of 163 DNA bands amplified by 20 primers, which divided the 19 varieties into four groups: Group Beijing, Group 85-5, Group Guolimao and the other Group.

CONCLUSION8 varieties of Group Beijing have a close genetic relationship, and so have varieties of Group 85-5, which provides information for Rehmannia glutinosa's breeding.

DNA, Plant ; genetics ; Plant Leaves ; genetics ; Plants, Medicinal ; genetics ; Polymorphism, Genetic ; Random Amplified Polymorphic DNA Technique ; Rehmannia ; genetics

NRT1 family proteins play an important roles for absorbing and transporting of nitrate in different plants. In order to identify the NRT1 family genes of Rehmannia glutinosa, this study used 11 NRT1 homologous proteins of Arabidopsis as probe sequences and aligned with the transcriptome data of R. glutinosa by using NCBI BLASTN software. Resulting there were 18 NRT1 proteins were identified in R. glutinosa. On basis of this, a series of the molecular characteristics of R. glutinosa NRT1 proteins including the conserved domains, the transmembrane structure, the subcellular location and phylogenetic features were in detail analyzed. At same time, it were systematically analyzed that the temporal and spatial expression patterns and characteristics of R. glutinosa NRT1 family genes in response to different stress factors. The results indicated that 18 R. glutinosa NRT1 family genes with the length of coding region from 1 260 bp to 1 806 bp, encoded proteins ranging from 419 to 601 amino acids, and all of they owned the domains of typical peptide transporter with 7 to 12 transmembrane domains. These R. glutinosa NRT1 family proteins mostly were found to locate on cellular plasma membrane, and belonged to the hydrophobic proteins. Furthermore, the evolutionary analysis found that the 18 R. glutinosa NRT1 protein family could be divided into two subfamilies, of which 14 NRT1 family genes might occur the positive selection, and 4 genes occur the passivation selection during the evolution process of R. glutinosa. In addition the expression analysis showed that 18 R. glutinosa NRT1 family genes have the distinct expression patterns in different tissues of R. glutinosa, and their expression levels were also obvious difference in response to various stress. These findings infield that 18 R. glutinosa NRT1 family proteins might have obviously different functional roles in nitrate transport of R. glutinosa. In conclusion, this study lays a solid theoretical foundation for clarifying the absorption and transport molecular mechanism of N element during R. glutinosa growth and development, and at same time for deeply studying the molecular function of R. glutinosa NRT1 proteins in absorption and transport of nitrate.
Anion Transport Proteins ; Membrane Transport Proteins ; Nitrates ; Phylogeny ; Plant Proteins/metabolism* ; Rehmannia/genetics* ; Transcriptome

The swollen root of Rehmannia glutinosa is used as one kind of important Chinese traditional medicine. The root of R. glutinosa usually swelled in rotational cropping but not in continuous cropping. The rhizosphere microorganisms of R. glutinosa under different farming condition were thought related to that. In this study, the endophytic fungi in the root of R. glutinosa growing in various soil conditions were isolated for the study of the relationship between the microorganisms and the root enlargement of their host plants. The dominant endophytes, Verticillium spp., Fusarium oxysporum, F. redolens and Ceratobasidium spp. were identified by morphological observation and 18S rDNA and ITS sequence analysis. The preliminary investigation showed that the excessive growth of Verticillium and Fusarium genus fungi is unfavorable for the R. glutinosa root swelling, but Ceratobasidium fungi has no effects on the root enlargement.
DNA, Fungal ; genetics ; DNA, Ribosomal ; genetics ; Fungi ; classification ; genetics ; isolation & purification ; Molecular Sequence Data ; Plant Roots ; microbiology ; Rehmannia ; microbiology

Based on the early transcriptome and digital differentially expressed profiling library construction in consecutive monoculture (two-year culturing) Rehmannia glutinosa, we screened and chose the twelve differentially expressed protein genes which might be related with calcium signal system. The spatiotemporal expression of these genes was measured by the real-time quantitative PCR, and the relative expression values of the genes related with calcium signal system in different development stages and tissues of normal growth (one-year culturing) and succession cropping of R. glutinosa (two-year culturing) was elaborated in detail. In addition, disposed succession cropping of R. glutinosa was treated with different levels of calcium signal blocking agents in order to verify the mode of action of calcium signal system on consecutive monoculture problem in R. glutinosa. Among the twelve genes, two calcium channels away from the cytoplasm were down-regulated expressed, while the ten calcium channels toward the cytoplasm were up-regulated expressed. The results implied that succession cropping caused calcium ions flowing from endoplasmic reticulum to cytoplasm. While the key genes in calcium signal respond components such as CBL, CBP, CIBP, PLC, etc. were down-regulated expressed significantly in succession cropping of R. glutinosa which were disposed with calcium signal blocking agents, the extent of the damage was relieved, and approached the normal growth (one-year culturing) level. This result strongly showed that calcium signal system participated in the perceiving, conducting and magnifying processes of succession cropping obstacles of R. glutinosa.
Calcium ; metabolism ; Calcium Signaling ; Gene Expression Regulation, Developmental ; Plant Proteins ; genetics ; metabolism ; Rehmannia ; genetics ; growth & development ; metabolism