Effects of Different Ratios of Red and Blue Light on the Morphology and Photosynthetic Characteristics of Anoectochilus roxburghii

This paper studied the effects of different light qualities on the growth and photosynthesis of Anoectochilusroxburghii. Under uniform temperature, humidity, CO2 concentration, and photosynthetic photon flux density conditions, the morphological indexes, chlorophyll, photosynthetic rate, stomatal conductance, and transpiration rate of nine kinds of red and blue LED combination light sources were analyzed. The results showed that the 1:1 blue to red light treatment was more conducive to the accumulation of fresh weight of A. roxburghii than other light; these conditions also caused an increase in the overall plant height and stem diameter of A. roxburghii. White light treatment had a significant effect on the accumulation of aboveground organs of A. roxburghii. The net light and rate were the highest under the white light treatment, and were negatively correlated with intercellular CO2 concentration. Blue light treatment promoted the increase of stomatal conductance and the transpiration rate of A. roxburghii, but the net photosynthetic rate was the lowest compared with other light treatments. The greater the proportion of red light, the lower the chlorophyll content, and the difference was significant. The blue chlorophyll content has a significantly higher chlorophyll content.