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.