异质光环境下黄檗幼苗雌雄植株的生理生化响应差异

Higher plants are subject to light stress in their lifetime, and few studies about sex response of dioecious plant under different light environment have been reported. The different resistance between sexes is an important factor to affect population development, community structure and component of forest ecosystem. Phellodendron amurense Rupr. was selected as our research object. Ph. amurense is an important woody dioecious plant, but studies involving gender differences except our group has not been reported. Our previous studies had shown that male and female of Ph. amurense were significant differences on physiology and biochemistry, but the physiological and biochemical factors were not clear. To solve this problem, the project intends to reveal male and female of Ph. amurense differences response to light environment from morphology, physiology, biochemistry, etc., to explain adaptation mechanism under heterogeneous environment light.

高等植物在其一生中均会受到光胁迫的作用，雌雄异株植物对光环境的性别响应差异还少有揭示，其性别间的抗逆差异将直接决定其种群繁衍、群落结构乃至整个森林生态系统组成发生变化。黄檗（Phellodendron amurense Rupr.）是重要的木本雌雄异株植物，但涉及雌雄异株性别差异的研究除本课题组外未见报道。我们的前期研究表明，黄檗雌雄植株在生理生化方面存在差异，但产生差异的生理生化基础并不清楚。针对这一问题，本项目拟从形态、生理、生化等方面揭示黄檗雌雄植株对异质光环境的响应差异，探究黄檗雌雄植株对异质光环境的适应机制。

项目以不同遮阴处理条件下的黄檗雌雄植株为材料，从形态、生理、代谢产物等方面揭示黄檗雌雄植株对异质光环境的响应差异，探究黄檗雌雄植株对异质光环境的适应机制。结果表明：（1）黄檗雌雄植株遮阴处理条件下在叶长、叶宽、株高生长、地上生物量、地下生物量存在显著差异，雄株个体表现出较高的株高生长量，总生物量在65%遮阴处理最大，表现为雌株大于雄株。（2）叶绿素含量在85%遮阴处理最大，雌雄株差异不显著。光合速率在35%遮阴处理最大，蒸腾速率在对照和35%遮阴处理最大，表现为雌株大于雄株。（3）游离氨基酸含量和总酚含量在85%遮阴处理最大，游离氨基酸含量表现为雌株大于雄株，总酚含量为雄株大于雌株。（4）CAT酶、POD酶活性均在对照处理时最大，SOD酶活性在85%遮阴处理最大，雄株在遮阴处理下酶活性大于雌株。（5）内源激素含量均在对照处理含量最高，生长素、赤霉素、玉米素均为雄株大于雌株。（6）可溶性糖和可溶性淀粉含量均在35%遮阴处理最大，雄株可溶性糖含量大于雌株，雌株可溶性淀粉含量大于雄株。黄檗受到遮阴胁迫时，形态及生理方面都做出调整，以适应低光环境,但雌雄植株响应策略有所不同。黄檗幼苗期不适应强光照条件，适度的遮阴有利于黄檗幼苗生长、更新，研究成果为黄檗幼苗林下更新机制及黄檗野生资源保护及雌雄分配格局研究提供依据。