Comparative Analyses of the Chloroplast Genomes of Patchouli Plants and Their Relatives in Pogostemon (Lamiaceae).

Pogostemon Desf., the largest genus of the tribe Pogostemoneae (Lamiaceae), consists of ca. 80 species distributed mainly from South and Southeast Asia to China. The genus contains many patchouli plants, which are of great economic importance but taxonomically difficult. Therefore, it is necessary to characterize more chloroplast (cp) genomes for infrageneric phylogeny analyses and species identification of Pogostemon, especially for patchouli plants. In this study, we newly generated four cp genomes for three patchouli plants (i.e., Pogostemon plectranthoides Desf., P. septentrionalis C. Y. Wu et Y. C. Huang, and two cultivars of P. cablin (Blanoco) Benth.). Comparison of all samples (including online available cp genomes of P. yatabeanus (Makino) Press and P. stellatus (Lour.) Kuntze) suggested that Pogostemon cp genomes are highly conserved in terms of genome size and gene content, with a typical quadripartite circle structure. Interspecific divergence of cp genomes has been maintained at a relatively low level, though seven divergence hotspot regions were identified by stepwise window analysis. The nucleotide diversity (Pi) value was correlated significantly with gap proportion (indels), but significantly negative with GC content. Our phylogenetic analyses based on 80 protein-coding genes yielded high-resolution backbone topologies for the Lamiaceae and Pogostemon. For the overall mean substitution rates, the synonymous (dS) and nonsynonymous (dN) substitution rate values of protein-coding genes varied approximately threefold, while the dN values among different functional gene groups showed a wider variation range. Overall, the cp genomes of Pogostemon will be useful for phylogenetic reconstruction, species delimitation and identification in the future.

[Identification of herba rabdosiae serrae from different plant resources by RAPD method].

OBJECTIVE: To identify the different plant resources of Herba Rabdosiae Serrae by using Random Amplified Polymorphic DNA ( RAPD ) Analysis. METHODS: The mini spin columns were used to extract the genomic DNA from five different plants of Herba Rabdosiae Serrae. With the DNA extracted from these plants as template,the 85 oligo nucleic acids (10 bp)as random primers,the polymer chain reaction (PCR) was done and the results were analysed by electro-pharoses. RESULTS: 12 primers were selected with polymorphism and 7 of them showed good polymorphism in RAPD map. CONCLUSION: RAPD method can be used to identify the plant resources of Herba Rabdosiae Serrae.

[Researches and applications on pesticides from Chinese medicine plant origin].

The research progress on Chinese medicine plant resources with pesticide activities, the active components and their reaction mechanism as well as the application and prospect were reviewed in this paper. Some proposals on the exploitation of traditional Chinese medicine plant origin pesticide were given. It is suggested to found compounds with pesticide activities from heat clearing and toxic clearing medicinal plants.

[Studies on the cell growth, differentiation and terpene lactone accumulation in Ginkgo biloba cell suspension cultures].

To provide supports for Ginkgo biloba cell engineering for production of Terpene lactones (Ginkgolides and bilobalide), the cell suspension were established from calli induced from zygote embryos and stems of 30-day-old seedlings respectively. The relationship between cell growth, differentiation and the terpene lactone accumulation in these suspension cultures were investigated. HPLC determination indicated that, the ginkgolide B was found in the embryo derived cell suspension cultures at 0.044% of cell dry weight, and this result was the first time reported in this study. The accumulation of terpene lactone in the suspension cultures derived from both the embryo and seedling stems are effected by the level of the cell differentiation. The ginkgolide B was only found in small cell aggregates in the size smaller than 2mm, and the highest level of ginkgolide B was accumulated in cell aggregates in the size smaller than 1mm; however, the cell aggregates in the size bigger than 3mm could only produced bilobalide and ginkgolide A. In the same size aggregates of the suspension cultures the terpene lactone accumulation is strongly effected by the source of the explant. When the size of cell aggregates was in less than 1mm, the concentration of bilobalide, ginkgolide A and B in the cell suspension cultures derived from the embryos was 2, 1.4 and 0.56-fold, respectively, higher than that of cell cultures derived from seedling stems.