气温升高与干旱胁迫对灵武长枣叶绿素荧光特性的影响

Effect of Elevated Air Temperature on Chlorophyll Fluorescence Parameters in Zizyphus jujube Mill.cv.Lingwu changzao Under Different Soil Drought Stress

以4年生灵武长枣为试材,采用红外线辐射器控制模拟增温环境、土壤自动灌溉系统控制土壤水分水平,设置2个大气温度水平、3个土壤水分水平的6个组合,处理灵武长枣植株,测定其叶绿素荧光动力学参数,研究灵武长枣在日间气温升高与土壤干旱胁迫长期交互处理下叶绿素荧光参数的变化。结果表明:处理40d时,灵武长枣在大气温度增高2℃左右的环境下,随着土壤干旱水平的加剧,初始荧光(Fo)、原初光能转化率(Fv/Fm)和PSⅡ的潜在活性(Fv/Fo)、光化学猝灭系数(qP)均有下降趋势;处理80d时,增温环境下,随着土壤干旱水平的加剧,Fo有升高趋势,而Fv/Fm、Fv/Fo明显下降,相对电子传递速率(ETR)呈先升高后降低的趋势,而非光化学猝灭系数(NPQ)随处理时间的延长始终高于常温环境。因此,气温升高2℃左右可缓解灵武长枣因土壤干旱引起的光抑制和电子传递速率的下降,并能提高土壤干旱胁迫下灵武长枣的光保护能力。

Taking4-year-old Zizyphus jujube Mill.cv.Lingwu changzao（Lingwu long jujube）as test material,using infrared radiation equipment to control simulating elevated temperature environment,and automatic irrigation system to control soil water levels,the chlorophyll fluorescence parameters of Lingwu long jujube was tested that treated by two air temperature levels and three soil water levels to study the effect of elevated air temperature and soil drought stress on chlorophyll fluorescence parameters in Lingwu long jujube.The results showed that when treated 40 days,Fo,Fv/Fm,Fv/Fo,qP were decreased with the increasing of soil drought stress under elevated air temperature 2 ℃.When treated80 days,Fo was increased and Fv/Fm,Fv/Fo were decreased with the increasing of soil drought stress under elevated air temperature,while NPQ was higher than that of ambient temperature treatment.All these indicated that elevated air temperature relieved decreasing of ETR and light inhibition in Lingwu long jujube caused by soil drought,and improved its light protection capable under soil drought stress.