模拟酸雨对不同颜色棉花种子萌发与幼苗生理特性影响的研究

 以5个不同颜色棉花品种为材料，通过不同pH值的模拟酸雨处理棉花种子，分别测定了发芽势、发芽率及POD活性、SOD活性和可溶性糖含量的变化。结果表明,不同的pH值模拟酸雨对5个品种的发芽势、发芽率均有一定的影响，发芽势均高于各自的对照，发芽率均低于对照，且随着模拟酸雨酸性的增强而降低。POD和SOD活性的变化也有一定的规律，pH值从高到低，POD活性呈现先降后升的趋势；SOD活性变化呈现先升后降的趋势，表明模拟酸雨对棉花幼苗的细胞发生了实质损伤，其酶活性不可逆下降。5个品种幼苗也受一定的模拟酸雨胁迫，叶片中可溶性糖含量有所增加，表明其对模拟酸雨胁迫的抵抗能力。结果显示酸雨对不同颜色棉花种子萌发与幼苗生理特性能造成一定的影响和危害。

Influences of Simulated Acid Rain on Seed Germination and Seedling Physiological Characteristics in Different Colored Cotton Varieties

Seeds of five different colored cotton varieties were treated by simulated acid rain with different pH values, then the germination energy, percentage of germination, the contents of POD, SOD and soluble sugars were tested. The results indicated that the simulated acid rain with different values influenced the germination energy and percentage of germination of the five cottons to different degrees. The germination energy of five varieties was higher than that of the controls and decreased significantly with the falling of pH values; percentage of germination also decreased with the falling of pH values but lower than that of the controls. With the falling of pH values, POD activity firstly decreased and then increased, higher than that of the controls at last; but SOD activity was firstly increased and then decreased. This showed simulated acid rain had damnified the cells of cotton seedling, the SOD activity decreased irreversibly. Soluble sugars in leaves of five different colored varieties increased a little after treated by simulated acid rain. This showed the cotton seedlings had some capability to tolerate the stress of simulated acid rain. Simulated acid rain was harmful for cotton seed germination and influenced physiological characteristics of cotton seedling.