CAJ | 학술논문

采用在根内生成有色铜沉淀的方法研究大豆(Glycine max)初生根凯氏带对铜离子的通透性.用真空泵抽取浓度为200 μmo1·L~(-1)的CuSO_4溶液进入根中,然后在重力作用下从根基部灌注400 μmol·L~(-1)的K_4[Fe(CN)_6]溶液,两种物质在根内相遇即可产生棕色的Cu_2[Fe(CN)_6]沉淀,根据沉淀的位置来确定铜离子所经过的途径.结果表明:Cu~(2+)可以穿过内皮层凯氏带.在木质部导管壁以及凯氏带至木质部之间的细胞壁处产生棕色沉淀,侧根发生的部位也产生了大量的沉淀:当抽取K_4[Fe(CN)_6]溶液后再灌注CuSO_4溶液,发现Cu~(2+)仍然可以穿过凯氏带,并在凯氏带外侧以及外皮层细胞的细胞壁处产生棕色沉淀.研究结果证明凯氏带并不是一个可以完全阻止离子进出的完美屏障.
채용재근내생성유색동침정적방법연구대두(Glycine max)초생근개씨대대동리자적통투성.용진공빙추취농도위200 μmo1·L~(-1)적CuSO_4용액진입근중,연후재중력작용하종근기부관주400 μmol·L~(-1)적K_4[Fe(CN)_6]용액,량충물질재근내상우즉가산생종색적Cu_2[Fe(CN)_6]침정,근거침정적위치래학정동리자소경과적도경.결과표명:Cu~(2+)가이천과내피층개씨대.재목질부도관벽이급개씨대지목질부지간적세포벽처산생종색침정,측근발생적부위야산생료대량적침정:당추취K_4[Fe(CN)_6]용액후재관주CuSO_4용액,발현Cu~(2+)잉연가이천과개씨대,병재개씨대외측이급외피층세포적세포벽처산생종색침정.연구결과증명개씨대병불시일개가이완전조지리자진출적완미병장.
Using a technique of insoluble salt precipitation, we investigated the permeability of endodermal Casparian bands (CBs) for Cu~(2+) in primary roots of soybean (Glycine max L. cv Nongda 5828). Insoluble brown crystals of Cu ferrocyanide, indicating passage of Cu~(2+), were observed after 200 μmol·L~(-1) CuSO_4 was sucked into the root from its medium by use of a pump and subsequent perfusion of xylem with 400 μmol·L~(-1) K4[Fe(CN)_6]. Under suction, Cu~(2+) could cross the endodermis apoplastically in soybean, with brown salt precipitates in cell walls of xylem and in the region between CBs and xylem vessels. Regions where laterals penetrated the endodermis showed brown salt precipitates as well. When sides of CuSC_4 and K_4[Fe(CN)_6] application were reversed, Cu~(2+) could still cross the CBs and induce brown salt precipitates outside CBs and cell walls of exoderm cells. The results suggest that CBs are not perfect barriers to apoplastic ion flux.