亚低温与干旱胁迫对番茄叶片光合及荧光动力学特性的影响  

Effects of sub-low temperature and drought stress on characteristics of photosynthetic and fluorescence kinetics in tomato leaves

作　　者：杜清洁 代侃韧 李建明[1] 刘国英[1] 潘铜华[1] 常毅博[1] 

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100 [2]西安市长安区园艺工作站,西安710100

出　　处：《应用生态学报》2015年第6期1687-1694,共8页Chinese Journal of Applied Ecology

基　　金："十二五"国家科技支撑计划项目(2011BAD29B01);国家高技术研究发展计划项目(2011AA100504)资助

摘　　要：利用人工气候室,研究了亚低温（8~15℃）和干旱胁迫（田间持水量的55%~65%）对盆栽番茄叶片光合特性、能量及电子流分配的影响.结果表明：与对照相比,亚低温胁迫下番茄叶片的光合色素含量降低,而干旱胁迫下升高.在亚低温或干旱胁迫下,番茄叶片的胞间CO2浓度、气孔导度及净光合速率均显著下降,气孔限制值升高,其共同处理下相应指标进一步降低或升高.亚低温或干旱单一胁迫提高了光呼吸速率,但共同胁迫下其光呼吸速率反而降低.无论是亚低温、干旱胁迫还是共同胁迫,均会导致初始荧光、PSⅡ原初光能转化效率和有效光量子产量下降,光系统发生损伤,并且PSⅡ激发能分配系数升高,光化学效率降低,过剩光能增加,总电子流及流向各交替电子流库的电子流减少.为耗散过剩光能,热耗散及交替电子流的比例增加.与亚低温和干旱胁迫单一处理相比,二者共同处理加剧了叶片的热耗散,但交替电子流比例没有进一步增加.By using tomato as material potted in climatic chamber, the photosynthetic characteris- tics and allocation of energy and electron flow were studied under sub-low temperature （8-15 ℃） and drought （55%-65% of field moisture capacity） conditions. The results showed that the photo- synthetic pigment content declined under sub-low temperature stress, but increased under drought stress. Both sub-low temperature stress and drought stress significantly decreased the intercellular CO： concentration, stomatal conductance and photosynthetic rate, and increased the stomatal limita- tion, which further decreased or increased under simultaneous treatment of sub-low temperature and drought stress. The photorespiration significantly increased under separate treatment of sub-low tem- perature and drought stress, but decreased under simultaneous treatment. The stress declined the F0, Fv/Fm and Fv1/Fm1, which showed the damage of photosystem. It increased the distribution of energy to PS Ⅱ and declined the photochemical efficiency, total electron flow and alternating elec- tron flow. Thermal dissipation and the ratio of alternating electron flow were elevated to dissipate the excess energy. Compared with separate treatment of sub-low temperature and drought stress, the simultaneous treatment made thermal dissipation higher, but did not make alternating electrons flow further increase.

关 键 词：番茄 亚低温胁迫 干旱胁迫 光合特性 能量及电子流分配 

分 类 号：S641.2[农业科学—蔬菜学]