采用盆栽试验方法研究了施用螯合铁肥(Fe-EDDHA)对不同铁效率大豆V4期叶片及根系超微结构的影响。结果表明:铁敏感品种缺铁处理下植株矮小且叶片发黄,而铁高效品种缺铁条件下植株稍小但叶色差异不大。两种处理下铁高效品种的叶绿素SPDA值无显著差异,铁敏感品种在缺铁条件下叶绿素SPDA值显著小于补铁条件下,也显著小于铁高效品种。铁敏感品种叶肉细胞中叶绿体和线粒体数量在两种处理下差异不大,但铁敏感品种缺铁处理下叶绿体不饱满呈长梭形且其中淀粉颗粒形状扁平,含量较少;铁高效品种在两种处理下线粒体和叶绿体数目差异不大,但总体上在补铁处理下叶肉细胞中淀粉颗粒的含量较高、颗粒较大。铁敏感品种根系细胞缺铁处理下形状不规则,细胞壁严重变形,原生质破裂外流且分布不均,细胞核及大部分细胞器有解体现象,而补铁处理下细胞结构则保持规则完整;铁高效品种在两种处理下根系细胞均规则完整,但补铁处理下原生质体浓厚且内含物较丰富。由此说明:缺铁胁迫对不同铁效率大豆品种植株大小、叶色、细胞超微结构都有影响,只是铁敏感品种受缺铁胁迫影响更大,而铁高效品种可能有较完善的耐低铁机制所以受缺铁胁迫影响较小。 Pot experiments were conducted to study the effect of Fe-EDDHA on ultrastructure of V4 leaves and roots with different iron efficiency. The results showed that the plants with short iron and yellow leaves were susceptible to iron deficiency when the iron-sensitive varieties were deficient in iron. Under the two treatments, there was no significant difference in the SPDA value of the chlorophyll content between the two cultivars. The SPDA value of the susceptible cultivar under iron deficiency was significantly less than that under the iron supplementation and also significantly less than that of the ferric high efficiency cultivar. However, the number of chloroplasts and mitochondria in the mesophyll cells of the iron-sensitive varieties was not significantly different under the two treatments, but the chloroplasts were not full-fledged and long-spindle in the iron-sensitive varieties and the starch granules were flat and the contents were less; There was no significant difference in the number of mitochondria and chloroplast when treated with iron, but the content of starch granules in mesophyll cells was higher than that in iron treatment. Iron-sensitive cultivars had irregular shape, severe cell wall deformity, uneven distribution of protoplasm, disintegration of most of the organelles and most organelles, and regular and complete cell structure under iron supplementation. Iron-efficient cultivars Under both treatments, the root cells were all regular and intact, but the protoplasts were rich and their contents were rich under iron treatment. Therefore, the effects of iron deficiency on the plant size, leaf color and cell ultrastructure of different iron efficiency soybean cultivars were all affected by the iron deficient stress. However, the iron sensitive cultivars were more affected by the iron deficient stress, while the iron high efficient cultivars might have better resistance to low Iron mechanism so less affected by iron deficiency stress.