Effect Of Light On Growth, Photosynthesis Characteristics And Effective Components Of Panax Notoginseng

As one of the most important ecological environment factors during the plant growth.Light produce an effect on the plant growth and development by light quality and lightintensity. Panax notoginseng is a typical shade-acclimated plants. But the mechanism of lightquality and light intensity how produce effect on Panax notoginseng is unclear.In this study two years old Panax notoginseng were used as the experiment material, weinvestigated the effects of different light quality and light intensity on Panax notoginseng bycontrast the growth, photosynthetic characteristics and effective components of Panaxnotoginseng in order to provide a theoretical basis for the high quality and high yieldcultivation of Panax notoginseng.The main results were as follows:1. In this study two years old Panax notoginseng were used as the experiment material,we studied the growth, photosynthetic characteristics and effective components of Panaxnotoginseng under eight different colors plastic shed as red, orange, yellow, green, cyan,violet, blue, white.The results showed that:(1)The plant height, stem length, compound leaf petiole length, middle leaf length, crownwidth were the maximum under the red light, orange light in turn.(2)The different light quality had no significant influence on based stem diameter, freshweight of above-ground, dry weight of above-ground.(3)The cyan light was beneficial to the biomass accumulation of underground. Dryweight of underground under cyan light was31.87%higher than that under white light.(4) Under blue light and yellow light, the net photosynthetic rate was the maximum.Under white light transpiration rate and stomatal conductance was significantly higher thanothers. Intercellular CO2concentration was the maximum under green light.(5)Panax notoginseng total saponins content was the maximum under white light, butunder yellow light, the maximum of Panax notoginseng total saponins content per plant was1.124times than white light.2. Two years old Panax notoginseng were used as the experiment material, we studied thegrowth, photosynthetic characteristics and effective components content while transmittancewas32%,16%,8%,4%and2%. The results showed that:(1)The compound leaf petiole length, leaf area, crown width were the maximum whiletransmittance was16%.(2)The stem diameter was inversely proportional to the plant height and stem lengthunder different light intensity. The plant height and stem length was the maximum whiletransmittance was2%. The stem diameter was the maximum while transmittance was32%.(3)Different light intensity had significant influence on flower in Panax notoginseng.Diameter of the flower disk was the maximum0.962cm while transmittance was4%. Lightintensity had the same significant influence on stem diameter and stem length of flower. Thestem diameter and stem length of flower were both proportional to light intensity.(4)Under different light intensity, the change of net photosynthetic rate, transpiration rateand stomatal conductance was the same. They were the optimum while transmittance was16%. The change of intercellular CO2concentration was a little bit different. It was themaximum while transmittance was32%.(5)The content of Panax notoginseng total saponins of underground increased along withthe increment of light intensity. The content of Panax notoginseng total saponins ofunderground was to the maximum4.751%while transmittance was16%, but then contentdecreased. The change trend of Panax notoginseng total saponins content per plant was thesame as Panax notoginseng total saponins. Its maximum content was0.165g/per whiletransmittance was16%.All the analysis shows that, there were greater differences on the growth, photosyntheticcharacteristics and effective components of Panax notoginseng under the different lightquality and different light intensity. Panax notoginseng showed characteristics ofshade-acclimated plants. While transmittance was16%and under yellow light, Panaxnotoginseng had better growth, higher net photosynthetic rate, more biomass accumulation inroot and Panax notoginseng saponin content per plant.Generally, there were greater effect on Panax notoginseng in different light quality anddifferent light intensity. We can cultivation high quality and high yield Panax notoginseng bycontrol light quality and light intensity according to the weather.