硫对旺长期烤烟气体交换及叶绿素荧光的影响

Effect of Sulfur on the Gas Exchange and Chlorophyll Fluorescence of Flue-cured Tobacco in Fast Growing Period

以烤烟品种K326为试验材料．通过液培法研究硫（0．01-16mmol／L）对旺长期烤烟气体交换及叶绿素荧光参数的影响。结果表明．硫对旺长期烤烟的类胡萝卜素和蒸腾速率（Tr）无显著影响．但4mmol／L硫浓度使烤烟叶绿素含量和净光合速率（Pn）显著升高，0．01、16mmol／L处理则显著降低。胞间CO2浓度（Ci）随硫浓度增加而降低；气孑L导度（Gs）在2～16mmol／L处理随硫浓度的升高而显著降低。4mmol／L处理烤烟的光化学有效量子产量（EQY）和光合电子传递速率（ETR）略高于2、8mmol／L处理．但显著高于0．01、16mmol／L处理。0．01、16mmol／L处理的非光化学猝灭（NPQ）相差较小，显著高于2～8mmol／L处理。0．01mmol／L处理的水裂解端失活程度（Fo／Fv）显著高于其它处理，而4mmol／L处理显著低于其它处理，2、8、16mmol／L处理之间差异较小。由此可见，4mmol／L处理促进旺长期烤烟叶绿素含量、Pn、EQY、ETR显著提高，NPQ、Fo／n显著降低。

Flue-cured tobacco variety K326 as the test material, a hydroponic experiment was carried out to study the effects of different concentrations of sulfur （0.01-16 mmol/L）on chlorophyll content, photosynthesis, and chlorophyll fluorescence parameters of flue-cured tobacco leaves in fast growing period. Concentration of sulfur had no significant influence on carotenoid and transpiration rate （Tr）. The contents of chlorophyll and the net photosynthetic rate（Pn）in 4 mmol/L concentration of sulfur were significantly higher than those in 0.01 and 16 mmol/L contrations of sulfur. The intracellular CO2 concentration （Ci）decreased along with increase of the concentrations of sulfur while the stomatic conductance（Gs）decreased from 2 to 16 mmol/L concentrations of sulfur in fast growing leaves. The EQY, ETR in 4 mmol/L concentration of sulfur had no significant difference with 2 and 8 mmol/L but those in 4 mmol/Lwere higher than the 0.01 and 16 mmol/L of concentrations of sulfur. The nonphotochemical quenching（NPQ）in 0.01 and 16 mmol/L concentrations of sulfur had no significant difference but they were higher than 2-8 mmol/L concentrations of sulfur. The Fo/Fv in 0.01 mmol/L concentration of sulfur was higher than those in the others while the Fo/Fv in 4 mmol/L concentration of sulfur was lower than those in the others. The Fo/Fv among 2, 8 and 16 mmol/L concentrations of sulfur had no significant difference. So the chlorophyll content, Pn, EQY, and ETR increased significantly and Fo/Fv and NPQ decreased in concentration of sulfur in 4 mmol/L in the fast growing period of flue-cured tobacco.