LED Light Spectrum Affects the Photosynthetic Performance of Houttuynia Cordata Seedlings

摘要

We investigated the effects of light-emitting diodes (LED) with various light spectrum (white, red, yellow, green and blue) on photosynthesis of Houttuynia cordata seedlings. The seedlings were either cultivated under florescent lamp or under various LED lights. The leaves were collected and chlorophyll fluorescence parameters, the contents of chlorophyll, soluble sugar and relative water were measured, chloroplasts were observed as well. The results showed chlorophyll fluorescence parameters as Fv/Fm, qP and qY values were the highest under blue LED light and the values were the lowest under green LED light. Red LED light resulted in the enhanced chlorophyll content compared with the other LED lights, and the chl a/chl b ratio did not change significantly among LED treatments. The soluble sugar content was not significantly different among the treatments. The red LED increased relative water content and the green LED decreased the water content. Observation of chloroplasts in the leaves of Houttuynia cordata seedlings showed chloroplast number and distribution were altered by various light spectrum where chloroplasts were smaller under blue LED, and appeared to be more scattered under red LED. Our results indicated that photosynthesis of Houttuynia cordata seedlings respond differently to various light spectrum emitted by florescent lamp and LED.