Malekzadeh Parviz, Khara Jalil, Farshian Shadi, Jamal-Abad A'zam Khalighi, Rahmatzadeh Samaneh
Department of Biology, Urmia University, Urmia, Iran.
Pak J Biol Sci. 2007 Jan 1;10(1):127-31. doi: 10.3923/pjbs.2007.127.131.
In acid soils worldwide cadmium toxicity is a major factor limiting plant growth. The harmful effect of cadmium is initially expressed as a reduction in growth followed by several other secondary responses. In this study, some of the toxic effects of Cd(+2) like induction of oxidative stress were investigated. The effect of metal ion on the root growth was considered in maize plants. Maize (Zea mays L.) seeds were sterilized with 2.5% sodium hypochlorite solution for 15 min and washed thoroughly with distilled water. These seeds then germinated in petri dish (20 cm) containing distilled water at 37 degrees C in the dark. After a 1 day incubation, uniformly germinated seeds were selected and transferred to Petri dishes (9.0 cm) containing filter paper moistened with 10 mL of distilled water. Each Petri dish contained 12 germinated seeds. Each treatment was replicated 4 times. The germinated seeds were allowed to grow at 27 degrees C in darkness and 5 mL of test solution was added to each Petri dish in the second day. The test solution contained 0, 0.25, 0.5, 0.75, 1, 3 and 5 mM CdCl2. Cadmium treatments, increased GPX and APX activities in root in the presence of 0.25, 0.5, 0.75 mM concentrations, but their activities were constant in 1, 3 and 5 mM. Increased concentrations of CdCl2 from 0.25 to 5 mM decreased root length progressively. However, no reduction of shoot length by CdCl2 was observed.
在全球范围内的酸性土壤中，镉毒性是限制植物生长的主要因素。镉的有害影响最初表现为生长减缓，随后是其他一些次生反应。在本研究中，研究了Cd(+2)的一些毒性效应，如诱导氧化应激。研究了金属离子对玉米植株根系生长的影响。玉米（Zea mays L.）种子用2.5%次氯酸钠溶液消毒15分钟，并用蒸馏水彻底冲洗。然后这些种子在含有蒸馏水的培养皿（20厘米）中于37摄氏度黑暗条件下萌发。培养1天后，选择均匀萌发的种子并转移到含有用10毫升蒸馏水浸湿的滤纸的培养皿（9.0厘米）中。每个培养皿含有12颗萌发的种子。每个处理重复4次。使萌发的种子在27摄氏度黑暗条件下生长，第二天向每个培养皿中加入5毫升测试溶液。测试溶液含有0、0.25、0.5、0.75、1、3和5 mM的CdCl2。在0.25、0.5、0.75 mM浓度下，镉处理使根系中的GPX和APX活性增加，但在1、3和5 mM时其活性保持恒定。CdCl2浓度从0.25 mM增加到5 mM时，根长逐渐降低。然而，未观察到CdCl2对地上部长度的降低作用。
