干旱胁迫对降香黄檀幼苗生理特性及根系形态特征的影响  

The variations of physiological and root morphological characteristics of Dalbergia odorifera seedlings under drought stress

作　　者：杨振德[1] 赵岩岩[1] 玉舒中[1] 徐丽[1] 刘震[1] 范彦如[1] 

机构地区：[1]广西大学林学院,南宁530004

出　　处：《林业科技开发》2014年第3期63-66,共4页China Forestry Science and Technology

基　　金：广西大学2011级大学生实验技能和科技创新能力训练基金(编号:SYJN20131616)

摘　　要：采用盆栽控制土壤水分法,研究了1年生降香黄檀幼苗在不同干旱梯度胁迫条件下相对电导率、游离脯氨酸含量、光合特性等生理指标以及根系形态参数的变化。结果表明:随着干旱胁迫的加强,降香黄檀幼苗叶片电导率和脯氨酸含量变化整体呈上升的趋势;净光合速率Pn、蒸腾速率Tr、气孔导度Gs均下降,胞间CO2浓度Ci先降后升;与正常供水(W1)相比,在轻度干旱胁迫(W2)条件下,降香黄檀叶片Pn的降低主要是由气孔限制引起的,而在中度干旱胁迫(W3)和重度干旱胁迫(W4)条件下则主要由非气孔因素引起的。在重度干旱胁迫下,降香黄檀总根长、总根尖数和平均根系直径均显著降低,说明降香黄檀幼苗的耐旱能力有限。The variations in physiological indexes including relative conductivity, free proline content, photosynthesis cha- racter and root morphological parameters are most concerned traits on drought stress. One-year-old potted seedlings of Dal- bergia odorifera T. Chen were studied with controlled watering, under different drought gradient stress. The results showed that, the leaf relative conductivity and free proline content increased, along with the stress strengthening. While net photo- synthesis （Pn）, transpiration （Tr） and stomatal conductance （Gs ） decreased, the internal CO2 （Ci） initially decreased and then increased with an increased peak. Comparing with normal water condition, the decreasement in P, observed was mainly limited by stomatal factor under mild water stress （W2） ; however, it was limited by non-stomatal factor under mo- derate water stress （W3） and severe water stress （W4）. Under severe water stress, total root length, total root tips and average root diameter decreased obviously, which showed the finite drought resistance ability for the seedlings of Dalbergia odorifera.

关 键 词：降香黄檀 干旱胁迫 生理特性 光合特性 根系 

分 类 号：S511.01[农业科学—作物学]