摘要
为了探明大豆干旱胁迫的生理特性,以‘豫豆19’为实验材料,采用盆栽方式,设置对照(CK),轻度干旱胁迫(L),中度干旱胁迫(M)和重度干旱胁迫(N)4个水分处理水平,研究了不同水分条件下大豆幼苗的生理生化响应。结果显示:随着干旱胁迫的加强,叶片中叶绿素含量降低,游离脯氨酸含量逐渐增加,可溶性糖含量显著升高。随着干旱胁迫时间的延长,叶片中丙二醛含量呈升-降-升的变化趋势,超氧化物歧化酶(SOD)活性呈现先增加后降低的变化趋势。干旱胁迫下,大豆的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)显著降低(P<0.05);水分利用效率(WUE)在轻度水分胁迫条件下有所提高,在中度胁迫下又有一定的下降,在重度胁迫下则明显降低;胞间CO2含量(Ci)在轻度和中度干旱胁迫下降低而在重度干旱胁迫下又明显升高,说明在轻度和中度干旱胁迫下,Pn的下降是由气孔因素造成的;在重度干旱胁迫下Pn的下降是由非气孔因素造成的。
In order to investigate the physiological characteristics of soybean under drought stress,a pot experiment was conducted to study the physiological and biochemical responses of soybean seedlings to drought stress.Four treatments were arranged： control（CK）,light drought stress（L）,moderate drought stress（M） and high drought stress（N）.The results showed that： with the strengthening of drought stress,the chlorophyll content decreased,while the contents of free proline and soluble sugar significantly increased.Along with the period of drought stress continued,the MAD content showed a trend of up-down-up.SOD activity was tended to increase and then decrease.The water stress resulted in progressively decreases in net photosynthesis rate（Pn）,stomatal conductance（Gs） and transpiration rate（Tr）,respectively,WUE increased a little under L and decreased to some extent under L,but obviously decreased under N.The intercellular CO2 concentration（Ci） decreased at light stress and moderate stress,but increased at high stress,which indicated that the decline of Pn was caused by stomatal restriction under light stress and moderate stress,but non-stomatal restriction under high stress.
出处
《中国农学通报》
CSCD
2012年第9期42-47,共6页
Chinese Agricultural Science Bulletin
基金
国家"973"计划课题"气候变化对旱涝灾害的影响及风险评估"(No.2010CB951102)
国家自然科学基金"水平潜流CWs水动力模拟及去污实证"(No.51079028)
上海市自然科学基金"CWs脱氮的水驱动机制及其模拟研究"(No.10ZR1400300)
关键词
大豆
苗期
干旱胁迫
光合作用
生理生化指标
soybean
seedling period
drought stress
photosynthesis
physiological-chemical index
