Role of Different Cover Crops on DTPA-Extractable Micronutrients in an Apricot Orchard

This study was conducted to compare the effect of different cover crop treatments on DTPA-extractable micronutrients (Fe, Mn, Zn, Cu) and soil pH in an apricot orchard with clay texture located in Malatya province of Turkey. For this purpose, 5 different experimental groups (Vicia villosa Roth (VV), Vicia pannonica Crantz (VP), Vicia pannonica Crantz and Tritikale mixture (70% + 30%, respectively) (VPT), Phacelia tanacetifolia Benth (PT), Fagopyrum esculentum Moench (FE)) and 3 control groups (mechanically cultivated (MC), herbicide treatment (HC) and bare control plot (BC)) were used in the apricot orchards. The soils were sampled from 0–20 cm and 20-40 cm depths in each plot for soil analyses. According to the obtained results, while cover crop treatments reduced pH values of soils according to the bare control, the cover crops increased the Fe, Mn and Zn contents of soils in the 0-20 cm soil depth. The highest Ext-Fe, Mn and Zn contents were obtained in the VV (14.83mg kg-1, 8.42 mg kg-1, 1.03 mg kg-1, respectively) at the 0-20 cm soil depth. As compared to bare control, highest percent increases in Fe, Mn and Zn contents were determined in the VV 27.73%, 31.69% and 37.54%, respectively. The greatest significant negative correlations in the VV treatment were observed between pH and Fe (-0.985**), between pH and Mn (-0.945**) and between pH and Zn (-0.764*). The greatest significant negative correlations in the VP treatment were observed between pH and Fe (-0.948**), between pH and Mn (-0.928**) and between pH and Zn (-0.722*). It was concluded based on current findings that cover crops, especially Vicia villosa Roth and Vicia pannonica Crantz could be incorporated into cropping systems to improve micronutrients and to provide a sustainable soil management.