盐胁迫对玉米幼苗生长的影响.doc

摘要：本实验分别采用不同浓度的盐溶液对玉米种子进行盐胁迫处理，利用浓度分别为0.002mol/L，0.004mol/L，0.006mol/L，0.008mol/L，0.01mol/L，0.012mol/L的Na+溶液处理玉米幼苗，测定玉米幼苗生长发育（株高、根长、干重、鲜重）、生理生化（叶绿素含量、可溶性糖含量）和抗性生理（SOD、POD、MDA、脯氨酸）。结果表明：不同浓度盐胁迫对玉米的生长生理发育各有不同程度的抑制作用。在盐浓度为0.012mol/L时，株高和根长都处于最短状态，株高是对照组的69.4%，根长是对照组的51.2%。干、鲜重则随着盐浓度的升高呈下降趋势，Na+ 浓度为0.012mol/L时鲜重和干重分别比对照组下降48.6%和25.2%。叶绿素则也随盐浓度增加而下降，当Na+浓度为0.006mol/L时叶绿素含量比0.004mol/L时含量高，但仍低于对照组。当Na+浓度为0.012mol/L时，叶绿素含量降为最低，比对照组降低了84.3%。同时，低浓度的盐对SOD、POD的活性有着促进作用，而高浓度时起到抑制作用，且在Na+浓度为0．006mol/L时达到促进最高点。而可溶性糖、MDA和脯氨酸含量则随着盐浓度的升高而增加，且Na+浓度0．012mol/L时含量增加最明显。

关键词：玉米幼苗; 盐胁迫; 生长

Abstract：This experiment using salt solution of different concentrations on corn seeds to salt  stress treatment, which make use of the concentration of NaCl 0.002mol/L, 0.004mol/L, 0.006mol/L,  0.008mol/L,0.01mol/L and 0.012mol/L to treatment. Determination of the corn seedling growth (plant height, root length, dry weight, fresh weight), physiological and biochemical (chlorophyll content, the content of soluble sugar) and physiological resistance (SOD, POD, MDA, proline). The results show that: Different concentrations of salt stress corn plant growth physiological development each have different levels of inhibition. When the salt concentration is 0.012mol/L, plant high and root length are in the shortest state, plant high is 69.4% in control group, root length is a control group of 51.2%. Dry and fresh weight is increased with the concentrations of salt is decreased, NaCl concentration of 0.012mol/L fresh weight and dry weight is decreased by 48.6% and 25.2% than the control group. Chlorophyll decreased with the salt concentration increase, When NaCl concentration of 0.006mol/L chlorophyll content higher than 0.004mol/L, but still lower than the control group. When NaCl concentration of 0.012mol/L, chlorophyll content is reduced to a minimum, which lower than in control group 84.3%. At the same time, low concentrations of salt has a role in promoting to the activity of SOD and POD, While high concentrations play a role in restraining, and in NaCl concentration of 0.006 mol/L reached a peak. But soluble sugar, MDA and proline content increased with increasing salt concentration and the concentration of NaCl 0.012mol/L content increased obviously. 

Key words: corn seedlings, salt stress, growth