Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
Plant Cell Environ. 2010 Oct;33(10):1767-78. doi: 10.1111/j.1365-3040.2010.02182.x.
We used Populus yunnanensis Dode., a native dioecious species in southwestern China, as a model species to study morphological, physiological, biochemical and ultrastructural responses to drought, salinity and their combination. Females exhibited more growth inhibition, gas exchange rate depression and reactive oxygen species (ROS) accumulation; higher lipid peroxide levels, lower osmotic adjustment capacity and ascorbate-glutathione cycle enzyme activities; and more damage to cell organelles than did males under drought, salinity and especially under their combination. In addition, we found sex-specific responses in total chlorophyll content (TC), carotenoid concentration and carbon isotope composition under different osmotic stresses. Our results indicated that: (1) females are more sensitive and suffer from greater negative effects than do males under drought, salinity and especially under their combination; (2) sexual differences in adaptive responses to drought, salinity and their combination are context dependent; and (3) sex-specific reactions under a combination of stresses are distinct from single-stress responses. Thus, these results provide evidence for adaptive differentiation between sexes in responses to osmotic stresses and in the sensitivity to environmental change.
我们使用中国西南部的本地雌雄异株杨树作为模型物种，研究其对干旱、盐度及其组合的形态、生理、生化和超微结构响应。在干旱、盐度，特别是在其组合胁迫下，与雄性相比，雌性表现出更明显的生长抑制、气体交换速率降低和活性氧（ROS）积累；更高的脂质过氧化物水平、更低的渗透调节能力和抗坏血酸-谷胱甘肽循环酶活性；以及更多的细胞器损伤。此外，我们在不同渗透胁迫下发现了总叶绿素含量（TC）、类胡萝卜素浓度和碳同位素组成的性别特异性响应。我们的结果表明：（1）在干旱、盐度，特别是在其组合胁迫下，雌性比雄性更敏感，受到的负面影响更大；（2）对干旱、盐度及其组合的适应响应存在性别差异，且依赖于环境背景；（3）胁迫组合下的性别特异性反应与单一胁迫反应明显不同。因此，这些结果为雌雄对渗透胁迫的响应和对环境变化的敏感性存在适应性分化提供了证据。
