【摘要】 利用OS5－FL叶绿素荧光调制仪研究低温胁迫（5±2）℃对蔗叶光合作用的影响．结果表明，低温胁迫下蔗叶叶绿素a荧光诱导动力学曲线发生明显变化，Fv／Fm、Fv／Fo、DCPIP光还原活性、量子产量（Y）和Rfd值降低，说明PSⅡ原初光能转换效率和潜在光合作用活力均受到抑制，不抗寒品种如MT70－611抑制程度明显高于抗寒品种如FA81－745；研究还表明，低温胁迫下荧光粹灭减慢，光化学碎灭系数（qP）和非光化学猝灭系数（qN）降低，说明低温胁迫也直接影响了光合作用的碳同化．MDA含量分析表明，低温胁迫下不抗寒品种的MDA含量增幅高于抗寒品种．并讨论了低温对光合作用影响的机制及利用叶绿素a荧光诱导动力学鉴定甘蔗抗寒性的可能性．更多还原

【Abstract】 The effects of low temperature (5±2)℃ on photosynthesis of sugarcane leaves were studied by using OS5-FL modulated chlorophyll fluorometer. The results indicated that chlorophyll a fluorescence induction kinetic curves of sugarcane were changed obviously after chilling treatments. The decrease of Fv/Fm, Fv/Fo,DCPIP photo-reductive activity, quantum yield and Rfd values suggested that the primary light energy conversion of PS Ⅱ and the potential photosynthetic activities had been inhibited. The decrement of the above parameters in the varieties with chilling-sensitivity was higher than that in the varieties with chilling-resistance. The decrease of the photochemical quenching (qP) and the non-photochemical quenching (qN) also implied the inhibition of the carbon assimilation. The increment of MDA content in the varieties with chilling-sensitivity was higher than that in the chilling-resistant ones. The discussions were made on the responsive mechanism of sugarcane to chilling temperature and on the possibility of determining the chilling resistance in sugarcane using chlorophyll a fluorescence induction kinetics.更多还原