Reducing Nitrate Concentration in Lettuce by Continuous Light Emitted by Red and Blue LEDs before Harvest
Influence of continuous light with different red/blue ratio on photon flux density (R/B ratio) on nitrate and soluble sugar content was studied by growing lettuce (Lactuca sativa L.) under continuous illumination delivered by light-emitting diodes (LEDs).Results showed that compared with the initial values,nitrate concentrations in leaf blade and petiole of lettuce were significantly decreased while soluble sugar contents were dramatically increased after 48h light.In addition,significant negative correlation between nitrate concentration and soluble sugar content was found both in leaf blade (r =0.89) and petiole (r =0.9).Compared with single red light treatment,the decrease in nitrate concentration and increase in soluble sugar content in lettuce under mixed red and blue light was more pronounced.The optimal R/B ratio of light for short-term measures to reduce nitrate accumulation in lettuce is 4,because the lowest nitrate concentration and the highest soluble sugar content were obtained under this light condition.It is concluded that pre-harvest short-term exposure to continuous light is an effective method for producing lettuce with low nitrate accumulation and high soluble sugar content.
Continuous light LEDs Nitrate R/B ratio Soluble sugar
Zhou Wanlai Liu Wenke Yang Qichang
Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Key Lab.for Agro-Environment and Climate Change,Ministry of Agriculture,Beijing 100081,P.R.China
国内会议
济南
英文
225-231
2011-04-20（万方平台首次上网日期，不代表论文的发表时间）