Samardjieva Kalina A, Gonçalves Rui F, Valentão Patrícia, Andrade Paula B, Pissarra José, Pereira Susana, Tavares Fernando
a IBMC - Instituto de Biologia Molecular e Celular , Universidade do Porto , Porto , Portugal.
Int J Phytoremediation. 2015;17(1-6):272-9. doi: 10.1080/15226514.2014.898018.
Zinc tolerance, accumulation, and organic acid production by Solanum nigrum, a known Zn accumulator, was studied during pre- and post-flowering stages of development. The plants, when challenged with Zn concentrations lethal to plantlets, showed an increase in tolerance from pre-flowering to post-flowering, which was accompanied by a reduction of Zn translocation to the aerial plant parts. Treatment with Zn induced a differential response in organic acids according to the plant organ and developmental stage. In the roots, where Zn concentrations were similar in pre- and post-flowering plants, a general decrease in organic acid in pre-flowering roots contrasted with the increase observed in post-flowering plants. In the stems, Zn induced a generalized increase in organic acids at both growth stages while in the leaves, a slight increase in malic and shikimic was observed in pre-flowering plants and only shikimic acid levels were significantly increased in post-flowering plants. This work shows that Zn accumulation and tolerance in S. nigrum vary during plant development--an observation that may be important to improve the efficiency of phytoremediation approaches. Furthermore, the data suggest the involvement of specific organic acids in this response.
对已知的锌积累植物龙葵在开花前和开花后发育阶段的耐锌性、锌积累及有机酸产生情况进行了研究。当植株受到对幼苗致死的锌浓度挑战时，从开花前到开花后其耐锌性有所增强，同时锌向地上部分的转运减少。锌处理根据植物器官和发育阶段对有机酸产生不同反应。在根部，开花前和开花后植株的锌浓度相似，开花前根部有机酸普遍减少，而开花后植株中则增加。在茎部，锌在两个生长阶段均导致有机酸普遍增加，而在叶片中，开花前植株中苹果酸和莽草酸略有增加，开花后植株中只有莽草酸水平显著增加。这项研究表明，龙葵的锌积累和耐锌性在植物发育过程中有所变化——这一观察结果对于提高植物修复方法的效率可能很重要。此外，数据表明特定有机酸参与了这一反应。
