不同硒形态对玉米根系形态和养分吸收的影响

材料，采用营养液培养方法研究了不同浓度Se（Ⅵ）和Se（Ⅳ）对玉米生长和养分吸收的影响。[结果]相同硒浓度下，Se（Ⅵ）处理的玉米地上部干重显著高于Se（Ⅳ）处理;低浓度硒处理[Se（Ⅵ）≤12.50 μmol/L，Se（Ⅳ）≤25.00 μmol/L]玉米幼苗中硒含量均随硒浓度的增加而增加。相同硒浓度下，硒浓度<12.50 μmol/L时，玉米地上部Se（Ⅵ）的累積量低于Se（Ⅳ）累积量，硒浓度≥12.50 μmol/L时，玉米地上部Se（Ⅵ）的累积量显著高于Se（Ⅳ）累积量。相同硒浓度下，Se（Ⅵ）处理的玉米幼苗氮、磷、钾累积量显著高于Se（Ⅳ）处理。[结论]低浓度硒[Se（Ⅳ）≤6.25 μmol/L，Se（Ⅵ）≤12.50 μmol/L]可促进玉米生长和养分吸收，表现为根长伸长、根增粗以及氮、磷和钾累积量的增加，高浓度硒导致玉米生长受到抑制，氮、磷和钾累积量减小。

关键词 玉米;硒酸钠;亚硒酸钠;根系形态;养分吸收

中图分类号 S143.7+9文献标识码 A

文章编号 0517-6611（2019）04-0153-05

Abstract [Objective]The effects of root morphology and nutrient uptake of Se（VI） and Se（IV） in different concentrations of maize seedlings were determined， which provided a scientific basis for crop remediation of seleniumeiched soils with reasonable selenium. [Method]The effects of different concentrations of Se（VI） and Se（IV） on corn growth and nutrient uptake were studied by using nutrient solution culture method. [Result]Under the same selenium concentration， the dry weight of Se（VI） treated maize was significantly higher than Se（IV） treatment; Low concentration selenium treatment [Se（VI）≤12.50 μmol/L， Se（IV）≤25.00 μmol/L]， selenium content increased with the increase of selenium concentration. At the same selenium concentration， when the concentration of selenium was<12.50 μmol/L， the accumulation of Se（VI） in the aboveground part of maize was lower than that of Se（IV）. When the concentration of selenium was ≥12.50 μmol/L， the accumulation of Se （VI） in the aboveground part of corn was significantly higher than the amount of accumulation in Se（IV）. Under the same selenium concentration， the accumulation of nitrogen， phosphorus and potassium in Se（VI）treated maize seedlings was significantly higher than that in Se（IV） treatment. [Conclusion]Low concentration of selenium [Se（IV）≤6.25 μmol/L， Se（VI）≤12.50 μmol/L] can promote the growth of maize and nutrient uptake， which is characterized by root length elongation， root thickening， nitrogen， phosphorus and potassium accumulation， high concentration of selenium. The growth of maize was inhibited， and the accumulation of nitrogen， phosphorus and potassium decreased.

Key words Corn;Sodium selenate;Sodium selenite;Root morphology;Nutrient absorption

硒是人类、动物所必需的微量元素，缺硒可引起人体某些重要的器官功能失调，进而产生病变，如克山病、大骨节病[1]。许多研究表明，硒具有防癌、抗肿瘤和抗衰老的作用[2]。虽然目前硒未被确定为高等植物必需的营养元素[3]，但它对植物的有益作用已经有了许多证明[4-5]。硒可以提高植物应对低温、干旱、高光、水害、盐害和重金属等多种非生物胁迫[6]。低浓度的硒可以提高作物的叶绿素含量，促进植物的光合作用，增强作物的抗氧化作用[4，7-8]。

推荐访问:形态 根系 养分 玉米 吸收

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