Abstract: Background: Gynostemma pentaphyllum is a kind of shade-tolerant plants. It can synthesize and accumulate gypenosides in large amounts. The gypenosides are a valuable medicine that against hypertension, hyperlipemia, obesity, neurological disorder, inflammation, immune-modulation, diabetes and tumours. Hypotheses: Light quality was proved to affect the growth and gypenosides accumulation obviously in G. pentaphyllum, and it affects the photosynthesis certainly. So, some relationships may exist among these parameters. Study site and dates: Experiments were carried out in the late May of 2014 at Jishou University, Hunan province, China. Methods: Measurements of growth features and photosynthesis as well as determination of total gypenosides were conducted in seedlings that planted under different light qualities, including white, red, blue and green light emitted by LED lamps. Results: Light quality had remarkable effects on plant growth, total gypenosides accumulation and photosynthesis. White light had significant effects on increases in biomass, stem diameter and newly sprouted leaves than homogeneous light did. Compared with blue and green light, white light presented a higher content of total gypenosides which was closest to that of red light, suggesting the effect of white light on gypenosides accumulation was involved in red light. The net photosynthetic rate under red light was higher than those under blue or green lights, but obviously lower than that under white light. Conclusions: It is suggested that the influence of light quality on growth and the accumulation of total gypenosides was associated with photosynthesis efficiency.

ABSTRACT Dolichomitriopsis diversiformis is an endemic and threatened moss in eastern Asia. In vitro culture and light microscopic observation were employed to study its developmental process from spore germination to the formation of young gametophyte, as well as effects of light and temperature on its spore germination and protonemal development. Microscopic observations revealed that its spores were positively photoblastic with exosporous germination, and sporelings were classified as the bryum-type. Light and dark conditions were compared to understand their effects on spore germination. In 24 h continuous illumination, all spores germinated in both 20 ℃ and 25 ℃. In contrast, in darkness at 20 ℃ from one to 30 days, spores did not germinate. However, when dark-cultured spores transferred to continuous light, they started to geminate in 48 hours. In addition, effects of 20 ℃ and 25 ℃ on sporeling were compared. In a continuous light condition, sporelings grew longer and developed more protonema branches in the 20 ℃ treatment than in the 25 ℃ treatment. It was interesting that a phenomenon of slow and hysteretic spore germination and protonematal development was observed in natural light and room temperature (5-10℃). These observations suggest that spore germination and sporeling development is regulated by light and temperature.