桑树叶片光系统Ⅱ对盐胁迫的生理响应  

Reactions of Photosystem Ⅱ in Mulberry Leaves for Salt Stress

作　　者：李鑫[1] 张秀丽[1] 张会慧[1] 许楠[2] 孙广玉[1] 

机构地区：[1]东北林业大学生命科学学院,黑龙江哈尔滨150040 [2]黑龙江省科学院自然生态与资源研究所,黑龙江哈尔滨150040

出　　处：《安徽农业科学》2013年第33期12827-12829,12838,共4页Journal of Anhui Agricultural Sciences

基　　金：国家自然科学基金项目(30771746;31070307);东北林业大学学术名师支持计划(2012)

摘　　要：[目的]为探究不同品种桑树叶片PSⅡ功能的耐盐性。[方法]以2个桑树品种"龙桑一号"和"青龙桑"为试验材料,利用叶绿素快相荧光动力学曲线(OJIP)研究盐胁迫对桑树叶片PSⅡ的影响。[结果]随着盐浓度的增加,2个桑树品种叶片的PSⅡ最大光化学效率(F v/F m)和潜在光化学活性(F v/F o)显著降低,且"龙桑一号"的降低幅度大于"青龙桑"。盐胁迫抑制2个桑树叶片电子传递链上PSⅡ受体侧Q A向Q B的电子传递,降低用于还原Q A的能量(TR o/RC)和叶片捕获光能的比例(φP o),增加热耗散的比例(φD o),说明盐胁迫降低桑树叶片光化学效率是由于Q A向Q B的电子传递速率下降和热耗散比例增加的双重因素引起的,而对桑树光系统中的PSⅡ供体侧的伤害程度较小。[结论]"青龙桑"比"龙桑一号"表现出较强的抵抗盐胁迫能力。[ Objective ] The research aimed to explore salt tolerance of PSI] in mulberry leaves of different cultivars. [ Method ] By using fast OJIP chlorophyll a （Chla） fluorescence transients, the effects of salt stress on the mulberry leaves photosystem II （PSII） of Longsang No. 1 and Qinglong mulberry were studied. [ Result] With the increase of salt concentration, the maximal yield of photosystem Ⅱ photochemistry （Fo/Fm ） and potential PSⅡ photochemistry efficiency （ Fv/Fo ） significantly decreased in two varieties of mulberry, and Longsang No. 1 decreased to a larger extent. Salt stress inhibited the electron transport from QA to QB of electron transport chain in two mulberry leaves, while the energy used for deoxygenizing QA and the ratio of the amount of photons decreased, the ratio of heat dissipation increased. These results indicated that the decrease of electron transport rate from QA to QB and the increase of heat dissipation rate resulted in the reduction of the photochemical efficiency in the mulberry leaves for salt stress. The electron donor side of PSII of mulberry leaves photosystem was slightly damaged. [ Conclusion] The salt tolerance of Qinglong mulberry was higher than that of Longsang No. 1.

关 键 词：桑树 盐胁迫 光系统Ⅱ 

分 类 号：S888[农业科学—特种经济动物饲养] Q945.1[农业科学—畜牧兽医]