Abstract: The rhizosphere of apple trees was applied earthworms inoculated by corn stalks treatmented with different valence and different concentrations of iron at the Caozhuang orchard of Y ongnian County and at the orchard of Quzhou Experiment Station of China Agricultural University,the 82year2old Fuji apple trees was taken.The experiment showed that earthworm can survived in the corn stalks treated with 20 000 mg/ kg iron(tested by the highest concentration) and turned the straw into vermicast to promote root growth and improve the apoplast Fe content of apple roots,earthworm was more adaptive to the two2valent iron than three2valent iron.The earthworm can transfer iron from organic materiel to the roots of fruit trees,the best treatment about increasing Fe+content of earthworm tissue and the apoplast Fe content of roots was 5 000 mg/ kg.The total iron content of earthworms,vermicast and roots was increased as the concentration of iron treatment increased.Iron significantly promoted root growth of apple trees.The number of new roots was significantly less in the vermicast that earthworm inoculated with no iron than in the vermicast using iron processing,the new roots was the most by 5 000 mg/ kg treatment in two different valence of the iron.Earthworm significantly promote the root to growth,the number of new roots was significantly less in the treatment with no inoculated earthworms than in the treatment which inoculated earthworms.The soil bulk density,soil pH,and pH value of the root apoplast and organic matter content in the soil were significantly improved by the Iron and earthworms.

Key words: Earthworms, Iron, Enrichment and translocation, Iron nutrinent of roots of apple trees

CLC Number: 

• S13