HCO_3^-、K^+和HSO_3^-对黄瓜幼苗光合作用的影响

Effects of HCO_3^-,K^+ and HSO_3^-on Photosynthesis of Cucumber Seedlings

本试验以‘津春4号’黄瓜幼苗叶片为试材,研究HCO3-、K+和HSO3-对黄瓜幼苗光合作用的影响,试图用KHCO3水溶液中的HCO3-作为碳源来补充CO2的不足,同时用NaHSO3适当的抑制黄瓜的光呼吸,进而提高光合速率。结果表明:HCO3-可以作为碳源来补充大气中CO2的不足,HCO3-、K+和HSO3-可以提高光合速率、叶片可溶性糖含量,可提高叶绿素a含量、叶绿素b含量及叶绿素总含量,从而增强了光合作用的原初反应,能显著提高PSI和PSII的光合电子传递速率,提高ATP合酶的活性,从而加快了光合磷酸化的进程。通过提高Rubisco羧化活性、PEPC酶的含量及活性,降低Rubisco加氧活性,加快了CO2的固定与还原。

Effects of HCO3^-,K^＋ and HSO3-on photosynthesis of cucumber seedlings was studied in this research. It is tried that HCO3-in KHCO3 be used as a carbon source to supplement the shortage of CO2. At the same time,NaHSO3 was used to restrain photorespiration to increase photosynthetic rate of cucumber seedlings. The results showed that HCO3-can serve as a carbon source to supplement the lack of atmospheric CO2. HCO3^-,K^＋ and HSO3-can promote photosynthetic rate,raise content of soluble sugar,improve the contents of chlorophyll a,b and total chlorophyll content in the leaves,and thus enhance the initial response of photosynthesis. HCO3^-,K^＋ and HSO3-can significantly improve the electron transport activity of PSI and PSII,enhance ATP enzyme activity and photosynthetic electron transfer rate. HCO3^-,K^＋ and HSO3-enhance RuBPCase activity,and PEPCase activity and content,and debase RuBPOase activity and speed up the fixation and reduction of CO2.