【作者】 蒲丹；

【导师】 李冠；

【作者基本信息】 新疆大学 ， 植物学， 2006， 硕士

【摘要】 选择新疆荒漠分布广泛、具有代表性的短命植物糙草(Asperugo procumbens L.),东方旱麦草(Eremopyrum orientale L.),独行菜(Lepidium apetalum Willd),抱茎独行菜(Lepidium perforatum L.)为研究材料,研究水分、光照、温度对其种子萌发率的影响,找出萌发的最佳条件;研究其在不同水分条件下生长过程中,生理生态指标的变化;利用Li-6400光合仪研究其在不同环境条件下(CO2、H2O、光照等)光合作用的变化规律。初步揭示这四种短命植物对环境信号反应的生理与分子机制,为揭示短命植物的短生育周期和其避开不良环境的调控机制提供一些资料。实验结果表明这四种短命植物萌发受光照条件的影响不大,受温度和水分的影响明显;糙草在低强度水分胁迫下可通过抗氧化酶之间的相互协调在一定时期能维持活性氧代谢平衡,并阻止或减弱膜脂过氧化的伤害,但随着较高胁迫强度和处理时间的延长,抗氧化酶活性显著降低,膜脂过氧化作用增加,且叶绿素合成遭到破坏;这四种短命植物在强光下表现为光抑制,在干旱条件下表现为净光合速率下降,气孔导度显著降低,水分利用效率变化差异不显著。更多还原

【Abstract】 This experiment focus on the widespread and representative wilderness ephemeral plant, Asperugo procumbens L., Eremopyrum orientale L., Lepidium apetalum Willd and Lepidium perforatum L., The influence of several factors such as H2O, illumination and temperature on their seed sprouting rate and physiological condition were studied. Li-6400 was used to find out the rule of photosynthesis change under the different environmental conditions (CO2, H2O, light). The experimental result indicated that illumination condition didn’t influence sprouts rate of Ephemeral plant more obviously than temperature and water did; under low intensity water stress, Asperugo procumbens L. maintain active oxygen balance by regulate the activity of various antioxidant enzymes and prevented the damage of superoxide radical, But as water stress aggravated or transact increased, antioxidant enzymes activities notably decreased, damage of superoxide radicals increased, also the chlorophyll synthesis is destructed. Light suppression of ephemeral plant was observed under high light intensity. Under the arid condition, photosynthesis rate decreased and cond reduced remarkably, but the H2O use efficiency didn’t change notable. The research studied the physiological and molecular mechanism of Ephemeral plant’s response to environment signal, and provides some reference to the secret of its short birth cycle.更多还原