强光下高温与干旱胁迫对花生光系统的伤害机制  

Damaging mechanisms of peanut(Arachis hypogaea L.) photosystems caused by high-temperature and drought under high irradiance

作　　者：秦立琴[1,2,3,4] 张悦丽[2,3,4] 郭峰[2,3,4] 万书波[2,3,4] 孟庆伟[1] 李新国[2,3,4] 

机构地区：[1]山东农业大学生命科学学院,泰安271018 [2]山东省农业科学院高新技术研究中心 [3]山东省作物与畜禽品种改良生物技术重点实验室,济南250100 [4]农业部黄淮海作物遗传改良与生物技术重点开放实验室,济南250100

出　　处：《生态学报》2011年第7期1835-1843,共9页Acta Ecologica Sinica

基　　金：国家“十一五”科技支撑计划资助项目(2006BAD21B04);山东省自然科学基金重点项目(ZR2009ZD007);山东省博士后创新项目专项资金(200802005);山东省农业科学院青年科研基金项目

摘　　要：为探讨高温和干旱胁迫对花生光合系统的不同影响机制,以鲁花14为试材进行高温(42℃)强光(1200μmol.m-.2s-1)(HH)、干旱(PEG6000,30%)强光(1200μmol.m-.2s-1)(DH)和强光(1200μmol.m-.2s-1)胁迫(NH)处理,以未处理为对照(CK)的实验。与CK及NH处理相比,HH和DH的最大光化学效率(Fv/Fm)和820 nm光吸收大幅下降,叶绿素荧光动力学曲线上J点相对荧光(Vj)上升,单位面积内吸收的光量子(ABS/CSm)、单位面积内反应中心捕获的光量子(TRo/CSm)和单位面积内有活性的反应中心的数目(RC/CSm)均出现大幅下降,而PSⅡ的关闭程度(1-qP)明显升高,依赖于叶黄素循环的非辐射能量耗散(NPQ)升高,同时超氧化物歧化酶(SOD)活性出现下降,丙二醛(MDA)和膜透性增加,这些结果表明,HH和DH胁迫引起了花生叶片的严重光抑制,但快速叶绿素荧光诱导动力学曲线中均没有出现K点,表明花生叶片光合系统放氧复合体(OEC)对高温和干旱胁迫不敏感,光合系统Ⅱ(PSⅡ)反应中心的受体侧更容易受到高温和干旱的影响,而对花生光系统造成严重破坏的主要原因则是过剩光能的积累,一方面虽然叶黄素循环可以耗散部分能量,但不是全部;另一方面水-水循环受到高温和干旱的影响不能有效起到能量消耗的作用,造成活性氧的大量积累。HH和DH处理对花生光系统造成的伤害相似,但DH处理对花生光系统的伤害程度大一些,强光下,高温和干旱对花生叶片的伤害位点及破坏机制却较为相似。In agricultural systems,abiotic stresses,such as high light,high temperature and drought,are responsible for most of the reduction that differentiates yield potential from harvestable yield.As one of important oil crops in China,and even in the world,the high and stable yield of peanut（Arachis hypogaea L.） is very important to guarantee the food safety.Previous studies most focused on peanut yield,root activity,leaf area,net photosynthetic rate,chlorophyll content,activity of some enzymes,e.g.superoxide dismutase（SOD）,peroxidase（POD）,and catalase（CAT）,and so on.However,effects of drought and high temperature stresses on damaging mechanisms of peanut photosystems have been seldom mentioned,and both coordination between photosytem Ⅱ（PSⅡ） and photosytem Ⅰ（PSⅠ） and response of electron transfer components to two kinds of stresses were unclear.In the present work,we try to investigate the effects of high temperature and drought stresses on PSⅡ and PSⅠ activity and coordination between PSⅡ and PSⅠ,and further to provide the theoretical basis to peanut cultivation. In the experiments,Luhua 14 was used as materials to investigate the responding mechanisms of peanut photosystems to high temperature and drought stresses.Detached leaves were exposed to high temperature（42 ℃） under high irradiance（1200 μmol·m-2·s-1）（HH）,drought（PEG-6000,30%） under high irradiance（1200 μmol·m-2·s-1）（DH）,and high irradiance（1200 μmol·m-2·s-1）（NH）,respectively,and non-treatment leaves were as controls（CK）.Relative to CK and NH,the maximal efficiency of PSⅡ（Fv/Fm） and absorbance at 820 nm decreased greatly in peanut leaves under HH and DH stresses,accompanied by the increase of relative variable fluorescence at the J-step（Vj）,the obvious decrease of absorption flux per excited CS（t=m）（ABS/CSm）,trapped energy flux per CS（t=m）（TRo/CSm） and active RCs per CS（t=m）（RC/CSm） calculated from the chlorophyll fluorescence transient curv

关 键 词：花生 光抑制 高温 干旱 活性氧 

分 类 号：S565.2[农业科学—作物学]