不同浓度锰胁迫对向日葵幼苗叶片生理生化特性的影响

Effects of Different Concentrations of Manganese Stress on the Biochemical Characteristics of Helianthus annuus L.Seedlings

为研究锰胁迫对向日葵幼苗的影响,以向日葵幼苗为实验材料,通过沙培盆栽法研究不同Mn^(2+)浓度胁迫下向日葵生长和生理生化特性的变化。结果显示:随着Mn^(2+)浓度的增加,向日葵幼苗叶片中丙二醛(MDA)、可溶性糖(SS)以及游离脯氨酸(Pro)的含量都呈现上升趋势;而幼苗叶片叶绿素、蛋白质(Pr)含量则呈现先升高再下降的趋势。Mn^(2+)浓度为100 mmol/L时,向日葵幼苗叶片的总叶绿素、叶绿素a和叶绿素b含量达到峰值,而后随着Mn^(2+)浓度的继续增加而显著下降;Mn^(2+)浓度为200 mmol/L时,蛋白质含量最高,之后急剧下降。综上可见,低浓度Mn^(2+)对植株有显著的促进生长作用,细胞代谢加快;高浓度Mn^(2+)对植株有显著的抑制作用,可导致细胞代谢紊乱,甚至植株死亡。向日葵可以种植在被低浓度重金属污染的土壤中,一方面可以加快土壤净化,另一方面可以促进植株的生长发育。

In order to explore the influence of manganese stress on Helianthus annuus L.seedlings,H.annuus L.seedlings were used as experimental materials to study the growth and physiological and biochemical characteristics of sunflower under different Mn^(2+)concentration stresses by sand culture potting method.The research results showed that with the increase of Mn^(2+)concentration,the content of malondialdehyde(MDA),soluble sugar(SS)and free proline(Pro)in H.annuus L.seedling leaves all showed an upward trend.The content of chlorophyll and protein(Pr)in seedling leaves showed a trend of first increasing and then decreasing.When the Mn^(2+)concentration was 100 mmol/L,the total chlorophyll,chlorophyll a and chlorophyll b contents in the leaves of H.annuus L.seedlings reached the peak,and then decreased significantly as the Mn^(2+)concentration continued to increase.When Mn^(2+)concentration was 200 mmol/L,the protein content was the highest,and then it decreased sharply.In summary,low concentration of Mn^(2+)can significantly promote plant growth and accelerate cell metabolism.High concentration of Mn^(2+)has a significant inhibitory effect on plants,which can cause cell metabolism disorders and even plant death.H.annuus L.can be planted in soil contaminated by low concentrations of heavy metals.On the one hand,it can accelerate soil purification,on the other hand,it can promote the growth and development of plants.