（毕业设计论文）《铬对玉米生长的影响》.docVIP

本科生毕业论文 毕业论文题目 铬（Cr6+）的根系吸收及其对玉米幼苗生长的影响 学 生 姓 名 胡 廷 旭 所 在 学 院 环境科学与工程 专业及班级 农业资源与环境0801 指 导 教 师 盛 海 君 完 成 日 期 2012 年 5 月 10 日 摘要 通过水培方法，研究了Cr6+的根系吸收特征及其对玉米幼苗生长的影响。结果表明，玉米中Cr6+含量随溶液中Cr6+浓度的增加而增加，根中Cr6+含量明显高于茎叶中的Cr6+含量。Cr6+对植物生长的影响表现为“低促高抑”。低浓度Cr6+（1.00mg/L）促进玉米根系形态发育，根长、根表面积、根体积及生物量明显增加；高浓度Cr6+（≥1.00mg/L）抑制玉米根系发育，当Cr6+浓度达到2.00mg/L时，即可极显著降低玉米幼苗的根长和根表面积。Cr6+处理使玉米幼苗叶绿素含量较不添加Cr6+的对照均有所下降，表现出“脉间失绿”症状，低浓度Cr6+处理因玉米生物量的增加造成的稀释作用使得这种“失绿”症状尤为明显。Cr6+对植物的“低促”和“高抑”，都会对植物造成伤害。生产上应引起足够的重视。 关键词：铬；根系形态；玉米 Abstract This article is about the study of Cr6 + root absorption characteristics and its impact on growth of maize seedlings through the hydroponic method. The results show that the corn Cr6 + content increased with increasing solution of Cr6+concentration. In the root, Cr6 + content is significantly higher than the leaves and stems. Low concentration of Cr6 + (1.00mg / L,) will promote the development of corn root morphological. the root length, root surface area, root volume and biological amount all been significantly increased; high concentration of Cr6+ (≥1.00mg/L,) Suppress corn root development .when of Cr6 + concentration reached 2.00 mg / L, you can very significantly reduce the corn seedling root length and root surface area. The corn seedling which was foster by Cr6+ have less chlorophyll content compared with the normal plants. It also shows the symptoms of pulse to pulse loss of green, low concentrations of Cr6+ processing blow up this phenomenon. Either the low-promoting or high inhibition will harm the plant. We should take seriously attention in production. Key words：chromium; root morphology; maize 目 录 TOC \o 1-3 \h \z \u HYPERLINK \l _Toc326148667 摘要 PAGEREF _Toc326148667