Hydroponic experiment was conducted to study the effect of peach seedlings (Prunus davidiana) grown in nutrient solution with different Iron (Fe) concentration. The results showed that Fe deficiency could inhibit growth of peach seedlings, the roots and shoots biomass of peach in Fe-free treatment was significant lower than that of other treatments, except for the peach seedlings treated with 60 mg/L Fe. The peach grown seedlings in nutrient solution with different Fe concentration, Fe content in roots increased significantly, in stems decreased significantly, in leaves increased significantly, except for the peach treated with 20 and 60 mg/L Fe, there was a marked drop in total Fe content in leaves compared with control. These results indicated that appropriate amount of Fe (Fe concentration was 20 mg/L) could favour the growth of peach seedlings; and excessive Fe (Fe concentration was 60 mg/L) cloud have deleterious effects on peach seedlings. In conclusion, Fe concentration was greater than 0 and less than 60 mg/L, which was suitable for peach growth, especially the peach seedlings treated with 20 mg/L Fe.

In order to study the changes of the photosynthetic pigment content, antioxidant enzyme activity and osmotic adjuster content, the Prunus davidiana seedlings were cultured into Hoagland nutrient solution which added various concentrations of iron solution. Then the results showed that photosynthetic pigment content and antioxidant enzyme activity were all higher in iron-treated P. davidiana seedlings, compared with that in control seedlings. When increased iron concentration up to 10 mg/L, the chlorophyll a, chlorophyll b and the total chlorophyll content gradually rose, but decreased at iron concentrations of 20, 30, 40 and 60 mg/L. Irrigating iron concentration of 60 mg/L was the best way to increase the activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and malondialdehyde (MDA) content. But for chlorophyll a/b ratio, it was the highest in no-iron seedlings. Moreover, the soluble protein content was the highest at iron concentration of 30 mg/L, but the lowest at 10 mg/L. Thus, the study concluded that irrigating iron solution could improve the growth and resistance to adverse circumstances of P. davidiana seedlings.