Investigation on reproductive characteristics of Polygonatum cyrtonema / 中国中药杂志

The study is aimed to investigate the reproductive biology characteristics of Polygonatum cyrtonema, especially including phenology, flower bud differentiation, flowering timing, floral traits, pollen vigor and stigma receptivity. The results showed that P. cyrtonema forms inflorescence before the leaves spread. In the wild, P. cyrtonema is mainly pollinated by insects such as bumblebees, with a seed setting rate of 65.12%. The seed setting rate of indoor single plant isolation or self-pollination enclosed by parchment paper bag is 0, indicating that it is self-incompatible. In Lin'an city, seedlings begin to emerge from mid-March to early April(the temperature is higher than 7.5 ℃), buds begin to emerge from the end of March to mid-April, and then undergo the full bloom stage from mid-to-late April, and the final flowering stage from the end of April to mid-May. The whole flowering period lasts 36 to 45 days. There are obvious differences in the phenology of different provenances. The flowers come into bloom from the base to the top along the aboveground main axis, which usually contain 4-22 inflorescences with(2-) 4-10(-21) flowers per inflorescence. The flowering pe-riod for a single plant is 26-38 days. The single flower lasts about 20-25 days from budding to opening and withers 2 days after pollination, and then the ovary will gradually expand. If unpollinated, it will continue to bloom for 3-5 days and then wither. Flower development period is significantly related to pollen vigor and stigma remittance. The pollen viability is the highest when the flower is fully opened with anthers gathering on the stigma, and the receptivity is the strongest when the stigma protrudes out of the perianth and secretes mucus. The fruits and seeds ripen in October, and proper shading can ensure the smooth development and maturity of the seeds. This study provides a basis for the hybrid breeding and seed production of P. cyrtonema.

Main nutrients and functional ingredients in flowers of Polygonatum cyrtonema and P. filipes / 中国中药杂志

To reveal the main nutrients and functional ingredients in the flowers of Polygonatum cyrtonema and P. filipes, the content of the polysaccharides, saponins, amino acids, total phenols, mineral elements, and the DPPH free radical scavenging rates were determined. The flowers and rhizomes of P. cyrtonema were collected from Qingyang in Anhui and Qingyuan in Zhejiang, while the flowers and rhizomes of P. filipes were collected from Longyou in Zhejiang, respectively. The results showed that the polysaccharides content in flowers varied from 60.88 to 97.00 mg·g~(-1), about half of that in rhizomes. The saponins content in flowers varied from 32.55 to 40.93 mg·g~(-1), which was close to the content in rhizomes. The content of total phenols ranged from 40.79 to 50.95 mg·g~(-1), approximately 4.5 times of that in rhizomes. The total amino acids content in flowers was 111.85 to 131.03 mg·g~(-1), about 2.3 times of the content in rhizomes. The essential trace element content was abundant in flowers. The contents of heavy metal elements were all within the limits set by the standards. The DPPH free radical scavenging rate IC_(50) varied from 1.77 to 3.25 mg·mL~(-1), less than one-fifth of that in rhizomes, showing a significant superiority of antioxidant activity compared to rhizomes. The results initially revealed the fundamental of "the flowers exceed the rhizomes in effect", the common saying about the traditional Chinese medicinal herbs over the years, indicating a great developing potential of the flowers. Besides, as polysaccharides, saponins, amino acids, total phenols and other nutritive substances in flowers differ widely among species and provenances, it's important to develop variety breeding to improve the quality and yield of flowers.