Variations in the morphological and chemical composition of the rhizomes of Polygonatum species based on a common garden experiment.

Polygonatum species have great potential in fighting chronic and hidden hunger. In this study, five Polygonatum species collected from different populations were cultivated in a common garden for 4 years. The species mainly differed in yield, saponin and polysaccharide contents, stem diameter, leaf width, inflorescence length, and floret inflorescence length. P. cyrtonema (PC) provides high-quality yield when planted in Zhejiang, with output as high as 7.5 tons per hectare and a promising breeding potential. Moreover, stem diameter can be used as an indicator of the harvest in the screening of varieties. In addition, the formation of plant genetic traits from different provenances is affected by the climatic factors of the origin. Furthermore, near-infrared spectroscopy combined with chemometrics for polysaccharide and saponin quantitation provides a rapid assessment of PC quality. Our findings provide a scientific basis for the development and sustainable utilization of PC as a high-yielding and high-quality forest crop.

[Relative molecular mass distribution and monosaccharide composition of polysaccharides in Polygonatum kingianum var.grandifolium].

Polygonatum kingianum var.grandifolium, different from most Polygonatum species in biological characteristics, sprouts and blooms in spring and autumn, respectively, and it is evergreen in winter.It is difficult to learn from the patterns of other Polygonatum plants because the chemical composition in P.kingianum var.grandifolium changes with phenology, which consequently restricts the production of high-quality medicinal and eatable substances.Samples of P.kingianum var.grandifolium in different months and ages collected from Xiushan, Chongqing were analyzed for polysaccharide content, polysaccharide relative molecular mass, and mono-saccharide composition by anthrone-sulfuric acid colorimetric assay, high-performance gel-permeation chromatography, and trimethylsilane(TMS) derivatization prior to GC-MS.The results showed that the polysaccharide content and composition in the rhizome of P.kingianum var.grandifolium were closely related to the growth period.New shoot sprouting promoted the accumulation of polysaccharides, and flowering and fruiting consumed polysaccharides.The highest polysaccharide content was found in April, reaching 134.04 mg·g~(-1).Polysaccharides in P.kingianum var.grandifolium were divided into five fractions according to the weight-average M_W, i.e., P1(2.02×10~7), P2(5.09×10~6), P3(1.37×10~6), P4(4.73×10~5), and P5(5.11×10~3), and P5 had the highest content.In terms of monosaccharide composition, polysaccharides were mainly composed of fructose, glucose, galactose, mannose, xylose, and arabinose with the average molar ratio of 1.31∶1.00∶0.90∶0.53∶0.22∶0.21.The results of the study provide a scientific basis for the precise harvesting and resource utilization of P.kingianum var.grandifolium.

[Polygonati Rhizoma: a crop with potential of being consumed as food and medicine].

As revealed by the investigation on the name change, biological characteristics, artificial cultivation, and edible history of Polygonatum kingianum var. grandifolium, it was described as a variation pattern of P. kingianum in the Chinese version of Flora of China(1978) and as a variant of P. kingianum in the revised English version of the Flora of China(2000). P. kingianum var. grandifolium, long been consumed as food by local folks, has been widely cultivated in its natural distribution area and circulated as Polygonati Rhizoma in the market. The important biological properties of P. kingianum var. grandifolium make it possess a great potential of being consumed as both medicine and food. The shoots of P. kingianum var. grandifolium sprout immediately out of the ground after seed germination and a new seedling will be formed at the same year, implying that its seedling cultivation period is at least two years shorter than that of P. cyrtonema. It can sprout more than twice a year, and the adult plants always remain evergreen, thereby obtaining higher biomass. Its rhizome biomass can be more than one time higher than that of P. cyrtonema. With reference to the diploid P. cyrtonema, flow cytometry revealed the polyploid and aneuploid forms in natural populations, which were tall and light-adapted with large underground rhizome. It can grow normally under the forest canopy and in the open field. Furthermore, P. kingianum var. grandifolium has important theoretical values for the study of ploidy variation, bud dormancy mechanism, etc.

First complete chloroplast genome of the rare medicinal plant Schnabelia tetrodonta.

Schnabelia tetrodonta is a medicinal plant used in traditional Chinese medicine. However, the molecular biology data of the species was too scarce to bioprospect the medicinal species. In this study, the first complete chloroplast genome (cp) of S. tetrodonta was sequenced and assembled based on the next generation sequencing. The cp genome is 157,004 bp in length, including a large single-copy (LSC) region of 83,605 bp, a small single-copy (SSC) region of 36,899 bp, and a pair of inverted repeat (IR) regions of 18,250 bp each. The genome encodes 134 genes, including 90 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. The GC content of whole genome is 37.80%. The phylogenetic analysis based on 20 complete cp sequences (19 genome sequences from the Teucrioideae of Lamiaceae and an outgroup of Ipomoea purpurea) revealed that S. tetrodonta was closely related to S. oligophylla.