A tomato cultivar, Gailiang Maofen 802F1, was selected as the planting material to investigate effects of NO on the absorption and distribution of Fe , Zn and Mn in tomato seedlings under copper stress using nutrient solution cultivation in greenhouse .The results show that the biomass and plant height of tomato seedlings are decreased by 33.7% and 23.1% respectively under the 50 μmol/L copper stress , while the addition of 100μmol/L SNP could remarkably alleviate this inhibition effect . For mineral elements , SNP could remarkably increase the Fe and Mn concentrations in roots and stems , and Fe and Zn concentrations in petioles and leaves , and the Zn concentration in stems and the Mn concentrations in petioles and leaves are reduced under the copper stress . Meanwhile the exogenous NO could improve Fe and Zn accumulation amounts in roots , stems, petioles and leaves and Mn accumulation amounts in roots and stems , while the exogenous NO reduces the transformation of the absorbed Fe , Zn and Mn red from roots to shoots .Under the Cu stress , the exogenous NO could remarkably increase the Fe and Zn concentrations in vacuole and organelle of all organs and decrease Fe , Zn and Mn concentrations in cell wall of roots and leaves .Mn mainly concentrates on the cell walls of stems and petioles that function as transport organizations , while its concentrations in vacuole and organelle of petioles and leaves are also increased .These results suggest that the exogenous NO could effectively regulate Fe , Zn and Mn rational distributions in organs and subcellular microzone under the Cu stress , so that the seedlings could keep a better balance between mineral nutrition elements and intracellular ion homeostasis to maintain normal physiological metabolism of tomato.%采用营养液培养方法，以“改良毛粉802F1”番茄为材料，研究外源一氧化氮（ NO，SNP为供体）对铜（ Cu）胁迫下番茄幼苗铁（ Fe）、锌（ Zn）、锰（ Mn）吸收分配的影响。结果显示，50μmol/L的Cu2＋胁迫下，番茄幼苗的生物量和株高显著降低了33.7％和23.1％，外施100μmol/L SNP可显著缓解这种抑制作用，提高Cu胁迫下番茄幼苗根系、茎中Fe、Mn含量及叶柄、叶片中Fe、Zn含量，降低茎中Zn含量及叶柄、叶片中Mn含量；根系、茎、叶柄、叶片Fe、Zn及根系和茎中Mn的累积相应增加；根系吸收的Fe、Zn、Mn向地上部的转运降低。 Cu 胁迫下，外源NO可显著提高番茄液泡、细胞器的Fe、Zn含量，降低根系和叶片细胞壁Fe、Zn、Mn含量。在作为转运组织的茎和叶柄中，Mn主要分布在细胞壁上，而在叶柄和叶片液泡、细胞器中也有增加。表明外源NO可以调控番茄幼苗各部位及亚细胞中Fe、Zn、Mn的合理分布，维持胞质离子稳态和矿质营养元素平衡，缓解铜胁迫，保证番茄幼苗正常的生理代谢。
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