中文摘要：

目的：探讨特定高温和强光逆境下番茄叶片中的环式电子传递（CEF）和线性电子传递（LEF）的光保护机制。创新点：通过引入电子抑制剂的方法系统分析了CEF和LEF对亚高温强光胁迫的响应。方法：将品种为＂辽园多丽＂的番茄幼苗（n=160）平均分成四组（表1）：组1,于常温常光照25°C,500μmol/（m2·s）条件下培养并作为对照;组2,叶片喷施蒸馏水并在亚高温强光35°C,1000μmol/（m2·s）（HH）条件下培养;组3,HH条件下叶片喷施100μmol/L敌草隆（DCMU,CEF抑制剂）;组4,HH条件下叶片喷施60μmol/L甲基紫精（MV,LEF抑制剂）。在处理5 d及恢复10 d期间,分别测定番茄幼苗叶片的光能吸收、激发能分配、光系统活性、类囊体膜完整性和ATP酶活性等指标。结论：CEF和LEF通过一定程度上改善叶片光能吸收及激发能分配,并且维持类囊体膜较高完整性和ATP酶活性,从而维持光系统活性并减少光抑制和光破坏程度。

英文摘要：

Objective： To evaluate the possible photoprotection mechanisms of cyclic and linear electron flux （CEF and LEF） under specific high temperature and high light （HH） stress. Methods： Six-leaf-stage tomato seedlings （＂Liaoyuanduoli＂, n=160） were divided into four parts： Part 1, served as control under 25 ℃, 500 pmol/（m2-s）; Part 2, spayed with distilled water （H20） under 35 ℃, 1000 pmol/（m2.s） （HH）; Part 3, spayed with 100 μmol/L diuron （DCMU, CEF inhibitor） under HH; Part 4, spayed with 60 pmol/L methyl viologen （MV, LEF inhibitor） under HH. Energy conversion, photosystem I （PSI）, and PSII activity, and trans-thylakoid membrane proton motive force were monitored during the treatment of 5 d and of the recovering 10 d. Results： HH decreased photochemical reaction dissipation （P） and the maximal photochemical efficiency of PSII （Fv/Fm）, and increased the excitation energy distribution coefficient of PSII （,8）; DCMU and MV aggravated the partition imbalance of the excitation energy （y） and the photoinhibition degree. With prolonged DCMU treatment time, electron transport rate and quantum efficiency of PSI （ETR= and Y1） significantly decreased whereas acceptor and donor side limitation of PSI （YNA and YND） increased. MV led to a significant decline and accession of yield of regulated and non-regulated energy Y NPQ and YNO, respectively. Membrane integrity and ATPase activity were reduced by HH stress, and DCMU and MV enhanced inhibitory actions. Conclusions： The protective effects of CEF and LEF were mediated to a certain degree by meliorations in energy absorption and distribution as well as by maintenance of thylakoid membrane integrity and ATPase activity.