【摘要】 以田间8年生沙地云杉为试验材料,研究干旱胁迫对沙地云杉的光合、叶绿素荧光参数的影响,为沙地云杉在干旱荒漠区的推广应用等方面提供理论依据。结果表明:(1)随着干旱胁迫加剧,沙地云杉的光合参数净光合速率(Pn)、气孔导度(Gs)、胞间C02浓度(Ci)和蒸腾速率(Tr)也随之降低,当土壤含水量为17%时,净光合速率(Pn)最大。胞间C02浓度(Ci)和气孔导度(Gs)同时降低,说明气孔因素是导致沙地云杉叶片净光合速率下降的主要因素。(2)干旱胁迫对沙地云杉叶绿素荧光参数均产生显著影响,其中最大光化学效率PSII(Fv/Fm)、实际光化学效率(ΦPSⅡ)、表观光合电子传递速率(ETR)对干旱胁迫的反应较为敏感,可作为评价沙地云杉抗旱能力的参考指标。综合分析各项指标表明,干旱胁迫对沙地云杉的光合荧光特性影响显著,气孔因素是导致沙地云杉叶片净光合速率下降的主要因素。更多还原

【Abstract】 The research focused on 8a Picea mongolica,by detecting the effects of drought stress on photosynthesis and chlorophyll fluorescence characteristics to provide theoretical basis of popularization and application of Picea mongolica in arid areas. The result showed that:( 1) With the degree of drought stress increasing,the net photosynthetic rate,stomatal conductance,intercellular CO2 concentration and the transpiration rate of the plant decrease; when the soil moisture content is 17%,the net photosynthetic rate was the largest,and stomatal conductance and intercellular CO2 concentration fall at the same time,showing that the leaves net photosynthetic rate decline is mainly restricted by stomatal factors.( 2) Drought stress has a significant impact on chlorophyll fluorescence parameters,the largest PSII photochemical efficiency( Fv / Fm),the actual photochemical efficiency( ΦPSⅡ),apparent photosynthetic electron transport rate( ETR) sensitively response to drought stress,and can be used as a reference index for sand spruce drought- resistant ability evaluation.更多还原