摘要
探讨干旱胁迫对高粱叶绿素荧光参数、光合速率和气体交换参数的影响,以便更好地了解高粱抗旱生理机制。以4个不同抗旱性高粱品种为材料,在盆栽条件下,分别在拔节期、开花期和灌浆期进行干旱胁迫,以正常灌水为对照,胁迫7d后测定高粱叶片叶绿素各荧光参数。结果表明:干旱胁迫下,高粱叶片最大光合效率(F_v/F_m)、实际光合效率(Φ_(PSⅡ))和光化学淬灭系数(qL)在不同生育时期均呈下降趋势,其中吉杂127降低幅度最大,在拔节期分别比对照降低了11.49%、16.09%和20.23%,而初始荧光(F_o)和非光化学淬灭系数(NPQ)则呈升高趋势,叶片光系统(PSⅡ)反应中心遭到破坏,原初光能转化效率降低。但与干旱敏感型品种(锦杂103和吉杂127)相比,抗旱型品种(吉杂305和锦杂106)表现出较高的Φ_(PSⅡ)和较大的相对电子传递速率(rETR),具有较强的光能转化能力。因此,干旱胁迫下,具有较高的实际光合效率和较大的相对电子传递速率是高粱品种抗旱性的重要生理特性。
The effects of drought stress on chlorophyll fluorescence parameters,photosynthetic rate and gas exchange parameters were studied in sorghum for better understanding the machanisms of drought resistance of sorghum.With 4 different droughtresistant sorghum varieties grown in pots as the materials,drought stress treatments were conducted at jointing stage,flowering stage and filling stage,respectively,and with normal irrigation as control.The chlorophyll fluorescence parameters of sorghum leaves were measured after 7-day period of stress.The maximum photosynthetic efficiency （Fv/Fm）,actual photosynthetic efficiency （ΦPSⅡ） and photochemical quenching coefficient （qL） of sorghum leaves at different growth stages showed a downward trend,Jiza127 had the biggest reduction which respectively decreased 11.49％,16.09％ and 20.23％ comparing with control group at jointing stage.The initial fluorescence （Fo） and non-photochemical quenching （NPQ） showed an upward trend,Photosystem Ⅱ （PS Ⅱ） reaction center of leaf was destroyed,resulting in a reduction of energy conversion efficiency of primary light.The ΦPsⅡ and relative electron transfer rate （Pm） of drought-resistant varieties （Jiza305 and Jinza106） were higher than those of drought-sensitive varieties （Jinza103 and Jiza127）,and their abilities of conversion of light energy were greater.The chlorophyll fluorescence parameters of ΦPSⅡ and relative electron transfer rate （Pm） in sorghum leaves of drought-resistant varieties were not sensitive to drought stress,and their higher values were important physiological characteristics for the drought-resistant sorghum varieties.
出处
《沈阳农业大学学报》
CAS
CSCD
北大核心
2013年第4期398-403,共6页
Journal of Shenyang Agricultural University
基金
现代农业产业技术体系建设专项资金项目(CAR-06-02-02)
关键词
高粱
干旱胁迫
叶绿素荧光参数
光系统Ⅱ
sorghum
drought stress
chlorophyll fluorescence parameters
photosystem Ⅱ
