盐处理对不同抗盐性小麦幼苗叶绿素荧光参数的影响

以耐盐小麦品种(德抗961)和盐敏感品种(鲁麦15)幼苗为材料,用0 mmol/L NaCl和200 mmol/L NaCl处理3 d,研究盐处理对小麦幼苗生长及叶绿素荧光参数的影响。结果表明,盐处理抑制小麦幼苗的生长和光合放氧速率,且对鲁麦15的抑制程度大于德抗961;盐处理下小麦幼苗PSⅡ最大光化学效率(Fv/Fm)没有明显变化;初始荧光(Fo)、PSⅡ实际光化学效率(ΦPSⅡ)、光化学猝灭系数(qP)均降低,而非光化学猝灭(NPQ)则升高,说明盐处理下PSⅡ原初光化学活性没有受到抑制,而PSⅡ实际光化学效率降低,起光保护作用的热耗散提高,但盐处理下品种间各参数变化幅度不同,Fo、ΦPSⅡ和qP均为抗盐性强品种变化程度小,而NPQ则升高幅度大。说明叶绿素荧光参数可以作为小麦耐盐鉴定指标。

Effects of Salt Stress on Chlorophyll Fluorescence Parameters in Wheat Seedlings with different Salt-tolerance

With salt-tolerant variety Dekang 961(DK961) and salt-sensitive variety Lumai 15(LM15) as tested materials,the wheat seedlings were treated resp.by 0,200 mmol/L NaCl for 3 d to study the effects of salt treatment on chlorophyll fluorescence parameters.The results showed that the salt treatments inhibited the growth and photosynthetic oxygen evolution rates of wheat seedlings,and the inhibition degree on LM15 was markedly greater than that on DK961.And there were no significant changes in maximal PSⅡ photochemical efficiency(Fv/Fm) under salt stress.However,under NaCl treatments,the initial fluorescence(Fo),the photochemical efficiency of PSⅡ(ΦPSⅡ) and the coefficient of photochemical(qP) were all decreased,while non-photochemical quenching(NPQ) was increased,indicating that the primary photochemical activity of PSⅡ was not inhibited and the actual photochemical efficiency of PSⅡ was decreased,while the heat disseminate which possess photoprotective effect was increased under the salt treatment.The change degree of Fo,ΦPSⅡ and qP of DK 961 was smaller than that of LM15,while the NPQ was increased greater than that of LM15.These results suggested that chlorophyll fluorescence parameters could be used as index for identifying salt tolerance of wheat cultivars.