不同基因型番茄幼苗对镉胁迫的生理响应及镉吸收差异

Different of Cadmium Absorption and Physiological Responses of Different Varieties of Tomatoes to Cadmium Stress

采用盆栽试验,通过研究不同浓度镉(1、5、10mg·kg-1)胁迫下4种基因型番茄圣粉1号、东圣1号、农城906和宝冠1号幼苗地上部及根部生物量、镉吸收量、活性氧含量(ROS)及其他生理指标,筛选出镉低积累基因型番茄品种。结果表明,不同基因型番茄对镉胁迫响应存在差异。随镉处理浓度增加,4个品种番茄幼苗地上部生物量显著下降(P<0.05)。地上部Cd吸收量呈增加趋势,在中浓度(5mg·kg-1)镉处理下达到峰值,品种间为宝冠1号>圣粉1号、农城906>东圣1号。4个品种番茄幼苗Cd转移率随镉处理浓度增加显著降低,其中东圣1号Cd转移率较低,根部Cd滞留较多,向地上部转移较少。4个品种番茄幼苗生理活性存在差异,宝冠1号番茄幼苗ROS含量及抗氧化酶(POD,CAT)活性随镉处理浓度增加变化幅度较大,东圣1号变化幅度相对较小。综合各项指标,4个基因型番茄中东圣1号为镉低积累品种。

A pot experiment was conducted to screen out and to indentify tomatoes varieties with low cadmium enrichment.The biomass,the Cd absorption,the content of ROS and other physiological characteristics of four tomato varieties Shengfen 1,Dongsheng 1,Nongcheng 906 and Baoguan 1 grown in Cd spiked soil were studied.The results showed that for all varieties,the upper part of the biomass was decreased（P0.05）and Cd absorption was increasd with the increasing concentrations of soil Cd2＋.However,the Cd absorption was different among four varieties,in 5 mg·kg-1Cd2＋ concentration,the Cd enrichment of all varienties was ranked Baoguan 1,Shengfen 1,Nongcheng 906 and Dongsheng 1.The translocation facto（rTF）of four tomatoes was droped with Cd content increasing,and TF of Dongsheng 1 was the lowest among varieties because Cd absorption of root was bigger than upper part.Under Cd stress,the physiological activity of four genotype tomatoes were also different.The content of ROS and the activities of antioxidant enzymes（POD,CAT）changed obviously of Baoguan1 with Cd content increasing,but the variation of Dongsheng1 was relatively small among four tomatoes.From the above we could easy concluded that Dongsheng 1 was low-accumulation of cadmium tomato.