樟子松幼树对持续沙埋胁迫的生理响应变化

Changes on physiological response of Pinus sylvestnis var. mongolica saplings in sand burial stress

为了解樟子松幼树在持续沙埋下的逆境生理特征变化,2013年春季在科尔沁沙地研究了不同深度沙埋处理下初期和后期(濒死期)樟子松幼树膜透性、渗透调节物质含量,保护酶活性的变化。研究结果表明:无论是沙埋初期还是后期,绝大多数处理的叶片相对含水量均高于或接近于非沙埋对照;随着沙埋深度增加,沙埋前期和后期的丙二醛含量均趋于下降,但沙埋后期大多数处理的丙二醛含量高于前期;沙埋初期膜透性呈波动式变化,大多数处理膜透性与对照差异不显著,沙埋后期膜透性总体高于沙埋前期,且波动异常;沙埋初期和后期的可溶性糖含量均随沙埋深度增加呈波动式下降,其中低于株高以上2cm沙埋的可溶性糖含量后期高于前期,其他处理相反;沙埋初期,随着沙埋深度增加,脯氨酸含量先增加后下降,大多数处理脯氨酸含量与对照差异不显著,沙埋后期全埋植株脯氨酸含量明显高于对照;沙埋初期,随着沙埋深度增加SOD和POD活性均先增加后下降,其中大多数处理的POD活性显著高于对照。

In order to understand changes of physiological response of Pinus sylvestris var. mongolica saplings to sand burial stress,osmotic regulation substances contents,protective enzymes activity and membrane permeability of Pinus sylvestris var. mongolica saplings in different sand burial depths were studied in the Horqin Sand Land of Inner Mongolia in growing season,2013. The results showed that both the early or late period of sand buried,RWC in the most treatments were higher than or close to non buried CK. The MDA contents tended to decrease with increase of burial depth and were higher in the late period than in the early period in the most burial treatments. The membrane permeability fluctuated in the early period in which the differences were no significant in the most burial treatments compared to the CK. The membrane permeability was significant higher in the late period that in the early period,with an abnormally fluctuation. Soluble sugar fluctuated to decrease with increase of burial depth in both the early and late period,which was higher in the late period than in the early period when sand burial depth was lower than 2cm above plant height,and other sand burial treatments instead. Proline contents increased firstly and then decreased with increase of burial depth in the early period,and were higher in the late period than in the early period. POD activities were significant higher in the most burial treatments that in the CK in both early and late period.