镉胁迫对烟草种子萌发和烟苗生长发育的影响

为探讨不同镉（Cd）胁迫对不同烟草品种种子萌发、幼苗生长的生理生态效应的影响,以吉烟9号、吉烟10号、延晒六号3个烟草品种为材料,研究了不同浓度的Cd溶液对烟草种子萌发以及烟苗生长发育的影响。结果表明,Cd胁迫下烟草种子发芽势、发芽率、发芽指数、活力指数、苗高均受到抑制;烟苗叶绿素含量降低,根冠比变小,生长受到抑制,CAT活性、SOD活性、可溶性糖含量随Cd浓度的增加呈先增后降的趋势,POD活性、MDA含量、Pro含量、Cd含量均随Cd浓度的增加而增加。可见Cd胁迫能不同程度地影响烟草种子萌发和烟苗生长发育,烟苗体内的抗氧化酶系统被破坏,多种酶活性不协调,生理生化过程紊乱,最终导致烟苗受害。

Effects of Cadmium Stress on Seed Germination and Seedling Growth of Tobacco(Nicotiana tabacum)

The purpose of this study was to investigate the effects of different concentrations of cadmium (Cd) on seed germination and physiological and ecological effects of seedling growth of different tobacco varieties. Three tobacco varieties (Ji 9, Ji 10, Shai 6) were used as test materials to study the effects of different concentrations of Cd on seed germination and seedlings growth of tobacco. Under Cd stress, the seeds germination potential, germination rate, germination index, vigor index and seedling height of tobacco were all inhibited; the chloropohyll content and the ratio of root to shoot of tobacco seedlings was reduced, the growth was inhibited. CAT activity, SOD activity, the content of soluble sugar increased first and then decreased with the increase of Cd concentration. POD activity, MDA content, free proline content increased with the increase of Cd concentration. In other words, under Cd stress, seed germination and seedling growth could be affected to some extent, the antioxidant enzymes in the seedlings were destroyed, enzyme activity was uncoordinated, and the physiological processes were disturbed, leading to tobacco seedling damage.