镉胁迫下磁场对绿豆幼苗根茎叶显微结构的影响

Effects of Magnetic Field on the Mung Bean Structure of Root,Stem and Leaf under Cd Stress

以绿豆(Vigna radiata)为实验材料,比较研究了不同剂量磁场处理绿豆种子对种子电导率、幼苗生长和叶绿素含量的影响以及镉胁迫绿豆幼苗根、茎、叶显微结构的影响.结果表明:1)与对照相比,400mT、600mT、800mT、1000mT磁场均显著提高了种子电导率,且随着磁场强度的增加电导率显著增大;2)400mT、600mT、800mT磁场均能显著提高绿豆幼苗叶片叶绿素含量和幼苗发育,比较而言600mT效果最好,1000mT处理则显著降低了叶片叶绿素含量,抑制了幼苗发育;3)与对照组相比,5μmol·L-1镉胁迫绿豆幼苗栅栏组织和海面组织细胞排列紧密,厚度变薄,而种子经过600mT磁场预处理后再进行镉胁迫,厚度接近对照组.对于茎和根而言,镉胁迫抑制了形成层细胞分裂,维管束体积缩小,而种子经过600mT磁场预处理后再进行镉胁迫,其维管束体积增大接近对照组.表明,600mT磁场预处理种子可改善镉胁迫对幼苗的伤害.

In order to determine the effects of magnetic field on the Mung bean（Vigna radiata）structure of root stem and leaf under Cd stress,changes in the leaf conductivity,root length,shoot length,fresh weight,the concentration of chlorophyll and structure of root,stem and leaf were analyzed.The results indicated that 1）the conductivity was enhanced step by step with the magnetic field increase;2）Pretreatment of 400mT,600mT and 800mT could improve significantly the seedlings growth and the chlorophyll concentration of leaf,and the best effects was 600mT;3）For the leaf structure,spongy tissue（st）and palisade tissue（pt）were thinned in the case dealing with 5μmol·L-1 Cd,and the thickness was recovered in the 600mT magnetic field pretreatment followed by 5μmol·L-1 Cd.For the root and stem structure,the cells size of vascular tissue（vt）diminished,and the size recovered when dealing with complex of 5μmol·L-1 Cd and 600mT magnetic field.