North American lake cress, Rorippa aquatica (Eaton) EJ Palmer & Steyermark (Brassicaceae), is listed as an endangered or threatened species. Lake cress shows heterophyllic changes in leaf form in response to the s...North American lake cress, Rorippa aquatica (Eaton) EJ Palmer & Steyermark (Brassicaceae), is listed as an endangered or threatened species. Lake cress shows heterophyllic changes in leaf form in response to the surrounding environment. Therefore, this species has received considerable attention from ecological and morphological perspectives. However, its phylogenetic position and taxonomic status have long been a subject of debate. To analyze the phylogenetic relationship of lake cress, we investigated chloroplast DNA sequences from 17 plant species. The results of phylogenetic reconstruction performed using trnL intron, trnG (GCC)-trnM (CAU), and psbC-trnS (UGA) indicated that lake cress is a member of Rorippa. Moreover, we found that the chromosome number of lake cress is 2n = 30. This result indicated that lake cress might have originated from aneuploidy of triploid species or via intergeneric crossing. Taken together, our results suggest an affinity between lake cress and Rorippa at the molecular level, indicating that lake cress should be treated as Rorippa aquatica (Eaton) EJ Palmer & Steyermark.展开更多
Falcaria vulgaris (sickleweed) is native to Eurasia and a potential invasive plant of the United States. No molecular markers have been developed so far for sickleweed. Characterization of molecular markers for this p...Falcaria vulgaris (sickleweed) is native to Eurasia and a potential invasive plant of the United States. No molecular markers have been developed so far for sickleweed. Characterization of molecular markers for this plant would allow investigation into its population structure and biogeography thereby yielding insights into risk analysis and effective management practices of the plant. In order to characterize the molecular markers, DNA samples were collected from eight populations in Iowa, Nebraska and South Dakota. Nuclear microsatellite markers developed for other Apiaceae taxa were screened and tested for intergeneric transferability to sickleweed. The chloroplast trnL intron and trnL-F intergenic spacer regions were sequenced and the sequences were used to design primers to amplify the microsatellites present within each region. We characterized eight polymorphic microsatellite markers for sickleweed that included six nuclear and two chloroplast markers. Our result showed intergeneric transferability of six nuclear microsatellite markers from Daucus carota to F. vulgaris. The markers we characterized are useful for population genetic study of F. vulgaris.展开更多
Most of Chinese medicinal herbs are subjected to traditional processing procedures, including stir-frying, charring, steaming, boiling, and calcining before they are released into dispensaries. The marketing and ident...Most of Chinese medicinal herbs are subjected to traditional processing procedures, including stir-frying, charring, steaming, boiling, and calcining before they are released into dispensaries. The marketing and identification of processed medicinal materials is a growing issue in the marketplace. However, conventional methods of identification have limitations, while DNA mini-barcoding, based on the sequencing of a short-standardized region, has received considerable attention as a new potential means to identify processed medicinal materials. In the present study, six DNA barcode loci including ITS2, psb A-trn H, rbc L, mat K, trnL(UAA) intron and its P6 loop, were employed for the authentication of 45 processed samples belonging to 15 species. We evaluated the amplification efficiency of each locus. We also examined the identification accuracy of the potential mini-barcode locus, of trnL(UAA) intron P6 loop. Our results showed that the five primary barcode loci were successfully amplified in only 8.89%——20% of the processed samples, while the amplification rates of the trnL(UAA) intron P6 loop were higher, at 75.56% successful amplification. We compared the mini-barcode sequences with Genbank using the Blast program. The analysis showed that 45.23% samples could be identified to genus level, while only one sample could be identified to the species level. We conclude that trnL(UAA) p6 loop is a candidate mini-barcode that has shown its potential and may become a universal mini-barcode as complementary barcode for authenticity testing and will play an important role in medicinal materials control.展开更多
文摘North American lake cress, Rorippa aquatica (Eaton) EJ Palmer & Steyermark (Brassicaceae), is listed as an endangered or threatened species. Lake cress shows heterophyllic changes in leaf form in response to the surrounding environment. Therefore, this species has received considerable attention from ecological and morphological perspectives. However, its phylogenetic position and taxonomic status have long been a subject of debate. To analyze the phylogenetic relationship of lake cress, we investigated chloroplast DNA sequences from 17 plant species. The results of phylogenetic reconstruction performed using trnL intron, trnG (GCC)-trnM (CAU), and psbC-trnS (UGA) indicated that lake cress is a member of Rorippa. Moreover, we found that the chromosome number of lake cress is 2n = 30. This result indicated that lake cress might have originated from aneuploidy of triploid species or via intergeneric crossing. Taken together, our results suggest an affinity between lake cress and Rorippa at the molecular level, indicating that lake cress should be treated as Rorippa aquatica (Eaton) EJ Palmer & Steyermark.
文摘Falcaria vulgaris (sickleweed) is native to Eurasia and a potential invasive plant of the United States. No molecular markers have been developed so far for sickleweed. Characterization of molecular markers for this plant would allow investigation into its population structure and biogeography thereby yielding insights into risk analysis and effective management practices of the plant. In order to characterize the molecular markers, DNA samples were collected from eight populations in Iowa, Nebraska and South Dakota. Nuclear microsatellite markers developed for other Apiaceae taxa were screened and tested for intergeneric transferability to sickleweed. The chloroplast trnL intron and trnL-F intergenic spacer regions were sequenced and the sequences were used to design primers to amplify the microsatellites present within each region. We characterized eight polymorphic microsatellite markers for sickleweed that included six nuclear and two chloroplast markers. Our result showed intergeneric transferability of six nuclear microsatellite markers from Daucus carota to F. vulgaris. The markers we characterized are useful for population genetic study of F. vulgaris.
基金supported by the Major Scientific and Technological Special Project for“Significant New Drugs Creation(No.2014ZX09304307)the Key Projects in he National Science and Technology Pillar Program(No.2011BAI07B08)
文摘Most of Chinese medicinal herbs are subjected to traditional processing procedures, including stir-frying, charring, steaming, boiling, and calcining before they are released into dispensaries. The marketing and identification of processed medicinal materials is a growing issue in the marketplace. However, conventional methods of identification have limitations, while DNA mini-barcoding, based on the sequencing of a short-standardized region, has received considerable attention as a new potential means to identify processed medicinal materials. In the present study, six DNA barcode loci including ITS2, psb A-trn H, rbc L, mat K, trnL(UAA) intron and its P6 loop, were employed for the authentication of 45 processed samples belonging to 15 species. We evaluated the amplification efficiency of each locus. We also examined the identification accuracy of the potential mini-barcode locus, of trnL(UAA) intron P6 loop. Our results showed that the five primary barcode loci were successfully amplified in only 8.89%——20% of the processed samples, while the amplification rates of the trnL(UAA) intron P6 loop were higher, at 75.56% successful amplification. We compared the mini-barcode sequences with Genbank using the Blast program. The analysis showed that 45.23% samples could be identified to genus level, while only one sample could be identified to the species level. We conclude that trnL(UAA) p6 loop is a candidate mini-barcode that has shown its potential and may become a universal mini-barcode as complementary barcode for authenticity testing and will play an important role in medicinal materials control.
