OBJECTIVETo understand the embryo after-ripening phenomenon of Panax quinquefolium, the growth and development process of fruit and seed was investigated in this study.

METHODThe growth and development characteristics of fruit and seed were obtained by field observation, the morphological changes were measured with a vernier caliper, paraffin section was used as well.

RESULT AND CONCLUSIONThe plant reached the most flowering numbers in 5-8 d after initial blooming time and the lag phase of embryo occurred in about 70 d. The size, fresh and dry weight of fruit and seed were all reached maximum in fruit maturation period. As the result showed, the development of seed was stopped at torpedo form of embryos, this conclusion can be applied to explore the morphological after-ripening mechanism of P. quinquefolium seed.

Fruit ; anatomy & histology ; growth & development ; Panax ; anatomy & histology ; growth & development ; Seeds ; anatomy & histology ; growth & development

OBJECTIVETo study the seed quality of Achyranthes bidentata from different sources and establish a standard of seed quality grading.

METHODSeed weight and moisture content determination, germination test, purity analysis were carried out by 100 grains method, high-temperature drying, double deck filter paper and GB/T354. 3-Seed Testing for Crops methods respectively. Eight collections were planted in several field plots.

RESULTThe 1 000 grains weight of 33 collections is 0.69 to 3.54 g with a variance coefficient 24.83%, the germination rate between 19.02% to 99% with a variance coefficient 38.24%. Seed moisture content and purity showed no significantly difference. K-means cluster analysis showed that 33 collections were divided into 3 grades: the first grade including 23 collections, the second and third grade including 5 collections respectively. Eight collections showed different field growth and yield characters.

CONCLUSIONThere are significant differences in seed quality of A. bidentata, so the classification management is needed in medicinal materials market. Germination test is an effective method before cultivating.

Achyranthes ; embryology ; Germination ; physiology ; Quality Control ; Seeds ; physiology

OBJECTIVETo study the effect of seedling quality on growth, yield and quality of Rehmannia glutinosa at harvest and build a basis for its GAP.

METHODThe seedling quality of R. glutinosa in main producing regions was surveyed to understand the current status of seedling quality. Field experiments with different varieties and seedling quality were conducted to measure dry matter accumulation with different growth of R. glutinosa and oligosaccharide content, and economic yield at harvest.

RESULTThe seedling was randomly selected by farmers in R. glutinosa producing regions. Seedling quality could significantly improve on seedling emergence rate, and promote seedling growth, especially with early stage R. glutinosa, finally increase yield at harvest. At harvest, 63% and 50% of yield with A and B seedling could be improved for variety of 85-5, and 50% and 47% of yield could be increased for variety of Beijing No. 1, compared to the C seeding.

CONCLUSIONIn cultivation, the seedlings with the diameter > 1.5 cm should be transplanted firstly.

Oligosaccharides ; analysis ; Rehmannia ; chemistry ; growth & development ; Seedlings ; chemistry ; physiology

Objective:To establish a method for quantitative analysis of the active ingredients including salidroside, rosarin and rosavin and content determination in Rhodiola rosea at different harvest months. Methods:HPLC was used on an X selectHSS T3 (250 mm×4.6 mm, 5 μm) column with mobile phase consisting of methol-acetonitrile-phosphoric acid (0.05%) aqueous solution for gradient elution at a flow rate of 1 ml/min. The wavelength was detected at 275 nm (salidroside) and 254 nm (rosarin, rosavin). The column temperature was set at 30 ℃ and the injection volume was 5 μl.Results:The peak areas of Salidroside, rosarin and rosavin showed good linear relationships ( r > 0.999) with the content in the ranges of 44-1 420, 10-307 and 18-573 μg, respectively. The method was precise, stable, repeatable and the sample recovery test all well satisfied the requirements of quantitative analysis. The highest accumulation of the active ingredients was observed in Rhodiola rosea in September and the content of salidroside, rosarin and rosavin were 0.66, 0.07 and 0.53 mg/g, respectively. Conclusion:This method is simple and rapid to evaluate the content of active ingredients in Rhodiola rosea.

Inhibition of Mycobacterium tuberculosis (Mtb) cell wall assembly is an established strategy for anti-TB chemotherapy. Arabinosyltransferase EmbB, which catalyzes the transfer of arabinose from the donor decaprenyl-phosphate-arabinose (DPA) to its arabinosyl acceptor is an essential enzyme for Mtb cell wall synthesis. Analysis of drug resistance mutations suggests that EmbB is the main target of the front-line anti-TB drug, ethambutol. Herein, we report the cryo-EM structures of Mycobacterium smegmatis EmbB in its "resting state" and DPA-bound "active state". EmbB is a fifteen-transmembrane-spanning protein, assembled as a dimer. Each protomer has an associated acyl-carrier-protein (AcpM) on their cytoplasmic surface. Conformational changes upon DPA binding indicate an asymmetric movement within the EmbB dimer during catalysis. Functional studies have identified critical residues in substrate recognition and catalysis, and demonstrated that ethambutol inhibits transferase activity of EmbB by competing with DPA. The structures represent the first step directed towards a rational approach for anti-TB drug discovery.