碳酸氢钾和亚硫酸氢钠对茄子幼苗光合作用的影响

Effect of KHCO_3 and NaHSO_3 on Photosynthesis of Eggplant Seedling

以"辽茄5号"(Solanum melongena L.)幼苗为试材,研究KHCO3和NaHSO3处理对茄子幼苗光合作用的影响。结果表明:KHCO3、NaHSO3及其复合能提高茄子幼苗的光合速率、光饱和点、CO2饱和点、表观量子效率、羧化效率、降低光补偿点和CO2补偿点。茄子幼苗叶片中含有磷酸烯醇式丙酮酸羧化酶(PEPcase)。KHCO3提高核酮糖-1,5二磷酸羧化/加氧酶(Rubisco)的羧化活性,NaHSO3使Rubisco的羧化活性、加氧活性、羧化活性和加氧活性的比值都提高。NaHSO3促进PSⅠ,PSⅡ和全链的电子传递,KHCO3对光合电子传递也有促进作用,但相对NaHSO3促进效果小些。KHCO3、NaHSO3及其复合增加根、茎和叶的干重。从影响因子看,K+、HCO3-和HSO3-具有促进光合速率的作用;促进PSⅠ和全链光合电子传递的主要为HSO3-,促进PSⅡ光合电子传递为K+、HCO3-和HSO3-;HCO3-是促进PEPcase活性的主要因子,HSO3-使Rubisco的羧化活性和加氧活性都增加,K+和HCO3-增加Rubisco的羧化活性。

Effect of K HCO3 and NaHSO3 and their mixtures on photosynthesis of eggplant seedlings was studied. The results showed that KHCO3, NaHSO3 and their mixtures could enhance photosynthetic rate of eggplant seedlings distinctly, raize light saturation point, CO2 saturation point, apparent quantum yield, carboxylation effciency and decrease light compensate point, CO2 compensate point. There was PEPC in leaves of eggplant seedlings. KHCO3 could enchance RuBPCase activity. NaHSO3 could enhance not only RuBPCase but also RuBPOase and the ratio of RuBPCase activity to RuBPOase activity. NaHSO3 could promote electron transport activity of PS I, PSI and whole photosynthetic chain. KHCO3 could also promote electron transport activity ,but the effect of promoting of photosynthesis was lower compared with NaHSO3. KHCO3, NaHSO3 and their mixtures could increase dry weight of roots,stems,leaves. For factors of improving photosynthesis, K^＋, HCO3^- and HSO3^- could improve photosynthetic rate. HSO3^- was a primary factor could improve electron transport activity of PSⅠ and whole photosynthetic chain. K^＋, HCO3^- and HSO3^- that could improve electron transport activity of PS Ⅱ. HCO3^- could improve PEPCase activity. HSO3^- could improve RuBPCase activity and RuBPOase activity. K^＋ and HCO3^- could increase RuBPCase activity.